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A Brief Tour of the Causes of Immunosenescence in the Adaptive Immune System

The open access paper I'll point out today covers some of the aspects of aging in the immune system, with a particular focus on the role of cytomegalovirus infection, and makes for interesting reading. The immune system is vital to health, not just in defending against pathogens such as bacteria, viruses, and fungi, but also because its agents work to destroy broken and harmful cells, such as those that have become cancerous, remove metabolic waste compounds where they accumulate outside cells, and help to regulate many necessary processes, from wound healing to the formation and destruction of synaptic structures in the brain. When the immune system declines into failure and dysfunction with advancing age, many other parts of our biology are dragged along with it into the downward spiral that ends in major organ failure and death. Finding ways to even partially reverse the progression of immune aging is obviously of great importance for the near future, a necessary part of the first generation of rejuvenation therapies. Fortunately, there are a few comparatively straightforward approaches that might bear fruit in the years ahead, despite the enormous and still incompletely mapped complexity of immune system biochemistry.

The immune system is broadly divided into innate and adaptive components, comprising different types of cell, different behaviors, and different vulnerabilities that lead to accumulated damage and disarray with time. The adaptive immune system is more recent in evolutionary terms, built atop the activities of the innate immune system. It is, as the name suggests, distinguished by being able to adapt to new threats rather than deploying the same set of armaments and strategies against every challenge, as is the case for the innate immune system. The adaptive immune system ultimately fails in large part because adaptation requires a memory of past actions, and over time the cells responsible for maintaining immune memory begin to crowd out the cells capable of taking action. Adults have a slow rate of creation of T cells, the cells of adaptive immunity. These cells are constructed in the bone marrow, but then migrate to the thymus to mature. That organ declines greatly shortly after childhood, and then further with increasing age, reducing its capacity for T cell maturation. This slow rate of replacement effectively puts a cap on the number of T cells present in the body under normal circumstances, and that combined with the lack of any effective limit on the numbers of memory T cells inevitably leads to disaster. Evolutionary processes are good at front-loading for success, producing biological systems that work very well in youth, but that hit architectural limits later in life.

The most effective near-term approach to this problem of misconfigured adaptive immunity is to improve upon and adapt the immune reboot therapies that are presenting being trialed successfully as treatments for severe autoimmune conditions. At the very high level, the age-damaged adaptive immune system is conceptually similar to an immune system fallen into autoimmunity: in both cases the problem is one of misconfiguration, the bad information recorded in immune cells leading to bad behavior. Wiping out these cells and starting over is a very promising approach. In the case of aging this doesn't deal with any of the forms of cellular damage that cause aging, but it should nonetheless do a great deal to restore effectiveness of the immune system in older people. The challenges are numerous: the present chemotherapies for immune ablation would need to be replaced with side-effect-free targeted cell killing technologies, such as that pioneered by Oisin Biotechnologies. Further, replacement of the immune system would likely have to be augmented with cell therapies in older people, as they would not be able to replace those cells rapidly enough on their own for safety. These are, however, very approachable challenges. The technologies largely exist already, and just need to be packaged, trialed, and moved into the clinic. Deploying this class of therapy will answer many of the questions asked in the paper linked below, and more rapidly than other forms of investigation.

Mechanisms Underlying T Cell Immunosenescence: Aging and Cytomegalovirus Infection

The human immune system must fight diverse pathogens and provide sufficient host protection throughout life. Memory T cells, which differentiate from naïve T cells upon primary antigenic stimulation and enable a rapid and robust response to previously encountered pathogens, are key players in adaptive immunity. The generation and maintenance of pathogen-specific memory T cells is crucial for life-long immune protection and effective vaccination. However, profound changes occur in the human immune system over time, known as immunosenescence. These age-related changes contribute to decreased immune protection against infections and diminished responses to vaccination in the elderly. Changes in T cell immunity appear to be have the most impact.

Although T cell numbers remain more or less constant over the human lifespan, pronounced age-associated changes occur in T cell composition (naïve vs. memory T cell subsets). It is well accepted that the functional naïve T cell output decreases after puberty due to thymic involution, resulting in increased homeostatic proliferation of existing naïve T cells and eventually phenotypic conversion of naïve T cells into virtual memory cells. In contrast to the shrinking naïve compartment and its impaired ability to activate and differentiate with age, the proportion of memory T cells increases during early life, remains stable throughout adulthood, but starts to show senescent changes after about 65 years. In humans, circulating memory T cells can be subdivided into two major phenotypically and functionally distinct populations: central memory T cells (TCM), which are largely confined to secondary lymphoid tissues, and effector memory T cells (TEM), which can traffic to multiple peripheral compartments.

One of the most prominent T cell changes to occur with age is the loss of the co-stimulatory molecule CD28 and the progressive accumulation of highly differentiated CD28- TEM cells, mainly in the CD8+ T cell population. These cells are characterized by decreased proliferative capacity, shortened telomeres, a reduced TCR repertoire, and enhanced cytotoxic activity. As CD28 is crucial for complete T cell activation, CD28 loss is associated with increased susceptibility to infections and a weakened immune response to vaccination in older people. It is thought that the memory T cells generated in youth are well preserved and remain strongly protective over decades, while T cell memory responses first derived in old age are severely impaired.

The ability to generate protective immune responses largely depends on the generation and maintenance of a diverse and well-balanced T cell repertoire. Several studies have shown contraction in T cell diversity corresponding to a shrinkage in the naïve T cell compartment in elderly individuals due to thymic involution. However, these studies do not take the dramatic influence of latent persistent infection into account, particularly cytomegalovirus (CMV) infection, which is known to be associated with age-related alterations in the T cell pool and function. Recent evidence suggests that homeostatic proliferation maintains the naïve CD4+ T cell compartment and its diverse repertoire, but not naïve CD8+ T cells, in CMV-negative individuals. A decline in naïve CD4+ T cell subsets occurs in the presence of CMV, but there is no depletion of naïve CD8+ T cells. In principle, thymic involution should have an equal impact on both CD4+ and CD8+ T cells. Therefore, the differences seen between the two subsets suggest that shrinkage of the naïve CD8+ T cell pool is more likely to be due to increased development of virtual memory T cells than the defective regeneration ability of an aged thymus. Moreover, unprimed "innate/memory-like" CD8+ T cells have recently been identified in humans. Taken together, these data imply that thymic involution might be less important for maintaining T cell diversity than previously thought.

Despite intensive studies of T cells providing some insights into immune system aging, they have a number of limitations that need to be taken into consideration in future investigations. First, most of our current knowledge on T cell aging is based on studies of circulating peripheral blood T cells, which only represent 2% of the total T cell pool. Circulating memory T cells predominantly reside in tissues other than the blood. Finally, human memory T cells are generated and maintained in the context of exposure to diverse viral infections throughout life, particularly CMV infection (over 90% of young people in developing countries). It is well-known that CMV plays an important role in human memory T cell function with aging. Therefore, distinguishing CMV seropositive individuals from others is important to provide a more accurate understanding of age-related memory T cell immunity.

Cytomegalovirus (CMV) is an ubiquitous β-herpesvirus that has co-evolved with humans over millions of years. Human CMV (HCMV) is a prevalent human pathogen, infecting 40-100% of world's population. CMV has the capacity to induce both lytic and latent infections to establish lifelong persistence in human hosts following primary infection. Long-term HCMV persistence has a profound impact on the immune system's composition and function, even in healthy HCMV-infected individuals, especially with respect to CD8+ T cells. One hallmark of latent HCMV infection is the progressive and substantial expansion of HCMV-specific memory CD8+ T cells over time, with HCMV-specific memory CD4+ T cells accumulating to a lesser extent. This accumulation of HCMV-specific memory T cells during viral persistence is termed "memory inflation." HCMV-specific memory T cells tend to gradually increase in number with age: in HCMV-infected elderly individuals, the CD8+ T cell response to HCMV antigens occupies nearly 50% of the entire memory CD8+ T cell compartment in peripheral blood, while approximately 30% of total circulating CD4+ T cells can be HCMV responsive.

Human cytomegalovirus (HCMV) persistence is thought to be a driver of immunosenescence in humans. The majority of HCMV-specific inflationary T cells are TEM cells with the typical age-related senescent T cell phenotype. It is widely accepted that late-stage differentiated CD28- T cells are a major characteristic of T cell aging, suggesting that persistent HCMV infection is associated with immunosenescence. This is further supported by the fact that the large population of HCMV-specific CD8+CD28- TEM cells that usually accumulate during HCMV persistence are absent in HCMV-seronegative elderly individuals, even those infected with other persistent herpes viruses. There is increasing evidence to suggest that memory inflation in HCMV infection is associated with impaired T cell immunity in elderly hosts. Despite the CD8+ T cell repertoire being diverse enough to recognize different viral epitopes soon after primary HCMV infection, clonal diversity starts to shrink with age, with a large proportion of the repertoire limited to a few high-avidity clones with a replicative senescent phenotype.

Taken together, HCMV infection in the elderly is implicated in immunosenescence and might have a deleterious impact on host immunity and enhance the aging process. Nevertheless, there remains considerable uncertainty regarding the causative role of CMV in immunosenescence. Although it is well-known that HCMV is a common cause of severe morbidity and mortality in immunocompromised individuals, we cannot exclude the possibility that HCMV might improve the polyfunctionality of CD8+ T cells and consequently benefit the host immune system, at least in young healthy individuals. Moreover, it is still unclear whether HCMV re-activation occurs more frequently in the elderly than in younger individuals. Hence, whether expansion of HCMV-specific CD8+ T cells over time is really deleterious in old age remains unknown.

Investigating the Mechanisms of Slowed Kidney Fibrosis via Calorie Restriction

The practice of calorie restriction produces sweeping changes in the operation of cellular metabolism and acts to modestly slow the progression of aging, extending life in most species and lineages tested to date. The focus in this open access paper is on the ability of calorie restriction to slow the fibrosis that accompanies aging, here in the kidney, though it is significant in other organs as well. Fibrosis is the inappropriate formation of scar-like tissue due to age-related failure in mechanisms of regeneration, a process that degrades organ function and is a major component of conditions such as kidney failure.

Chronic kidney disease (CKD), which is defined by reduced glomerular filtration rate, proteinuria, or structural kidney disease, is a growing problem among the aging population, to the extent that the elderly have an average prevalence of CKD that is three to five times higher than that observed in young and middle-aged populations. Accordingly, CKD predisposes the elderly to a high risk of cardiovascular events and premature death. Morphological and functional changes that accompany kidney aging are thought to contribute the development of CKD in the elderly. For example, processes that characterize kidney aging include glomerulosclerosis, interstitial fibrosis, tubular atrophy, vascular sclerosis, and loss of renal function. The mechanistic basis of kidney aging is cellular senescence, which is characterized by the inability of cells to proliferate despite the presence of ample space, nutrients and growth factors in the medium. Although renal fibrosis has been observed in elderly individuals in the absence of overt CKD, the relationship between cellular senescence and fibrosis during kidney aging is yet to be determined.

Epithelial-mesenchymal transition (EMT) is the process whereby differentiated epithelial cells undergo a phenotypic conversion that gives rise to matrix-producing fibroblasts and myofibroblasts. EMT is increasingly recognized as a key process that contributes to kidney fibrosis and the decline of renal function. Age-related changes in the levels of transforming growth factor-β (TGF-β), epidermal growth factor (EGF), insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF) result in a complex shift of the microenvironmental milieu that is thought to affect tissue homeostasis under both normal and abnormal conditions, triggering EMT and progressive fibrosis. Given that senescence and EMT play well-documented roles in the etiology and progression of age-associated CKD, the development of therapeutic interventions to retard or reverse these processes is warranted.

Here, we first examined compared age-related metabolic parameters and renal function between the groups of rats. Compared to the young rats, increases in age-related proteinuria, hypercholesterolemia and hypertriglyceridemia were observed in the older rats. We proceeded to demonstrate increased cellular senescence, as indicated by overexpression of P16, P21 and SA-β-gal in the kidneys of the aging rats. Cellular senescence is not only a marker of renal aging but also actively participates in the process. Furthermore, senescent cells secrete inflammatory factors and growth factors, resulting in a complex shift within the cellular microenvironment, which induces EMT. Increased levels of EMT as a function of age were demonstrated in this study. We found that EMT was increased in the older rats, compared with the younger rats, indicating that EMT increases as a function of age. Given that cellular senescence and EMT contribute to the decline in renal function with age, we investigated the effect of interventions on both senescence and age-related EMT in our rat models.

While previous studies have shown that caloric restriction (CR) decreased the abundance of senescent cells, improved telomere maintenance and reduced the levels of oxidative damage markers in the small intestine and liver, and alleviated age-related increase in EMT in the thymus, similar studies in the aging kidney have been lacking. Here we report that short-term CR alleviates cellular senescence and EMT in the aging kidney. However, it should be pointed out that even were our study to substantiate short-term CR as an effective intervention for cell senescence and EMT, the degree of restriction required would limit the utility of this intervention. As an alternative strategy, new research has focused on the development of caloric restriction mimetics (CRMs). The objective of CRM research is to identify compounds that mimic the effects of CR by targeting metabolic and stress response pathways affected by CR without actually restricting caloric intake.

With respect to how short-term CR and CRM treatment might directly impact cellular senescence and EMT, one interesting candidate is the AMPK-mTOR signaling pathway. In the in vivo experiments, we demonstrated that AMPK/mTOR signaling in kidney was downregulated with age, and that this was reversed by short-term CR and CRM treatment. In order to further verify this pathway, we induced EMT and cellular senescence of proximal tubular cells (PTCs) in vitro with high glucose. We found that exposure of PTCs to high glucose for 48 hours resulted in the high glucose-induced EMT and cellular senescence, decreased expression of activated AMPK and decreased AMPK/mTOR signaling. Costimulation of PTCs with high glucose and a CRM, both of which activate AMPK, alleviated high glucose-induced EMT and cellular senescence, and increased AMPK/mTOR signaling. Moreover, mTOR was upregulated, and EMT and senescence were increased in AMPK-silenced cells, but were not alleviated in AMPK-silenced cells that had been treated with a CRM. These results indicated that the CRM inhibited EMT and senescence of PTC via AMPK/mTOR signaling. It is possible that the data presented here could be extrapolated to explain the mechanisms of fibrosis seen in other organs during aging, and to provide strategies to overcome this process.

Link: https://dx.doi.org/10.18632/oncotarget.14884

Help to Support LongeCity Affiliate Labs

The LongeCity community is presently building a small fund from philanthropic donations in order to help support a selection of affliate laboratories involved in the development of therapies to treat aging as a medical condition. In the past, LongeCity has done a good job of funding small research projects in the field, and this is a worthy continuation of such efforts. Even modest amounts of funding can help to smooth the development and validation of early stage research in the field. If you have a little money to spare, please do consider making a donation.

The LongeCity Affiliate Labs are small, research-focused enterprises or independent academic research groups led by a scientists with strong ties to the LongeCity community and a proven track record of commitment to scientific inquiry directly relevant to the LongeCity mission. These leaders and their colleagues are not just trailblazers in advancing important areas of regenerative and rejuvenation research, but also incredibly helpful when there is a community need for peer review, when providing advice and training to a young scientist, and in providing the expertise and tools to test the novel, controversial, or promising scientific leads sourced from the LongeCity community and beyond.

There is a small support fund that the labs can draw on to flexibly support their research activities. While not a substitute for private investment and public sector grants, the ability to flexibly try out a new idea without needing to assemble lengthy proposals to funding bodies can be an invaluable accelerator to research progress. All Affiliates have an active link to the LongeCity community, so there is a level of accountability and responsiveness beyond anything encountered in traditional research donations. By donating to the Affiliate Labs fund, Members can be assured that every penny goes directly to an expert personally and professionally committed to making a difference in the scientific conquest of death. Current affiliate labs are: Alexandra Stolzing, Loughborough University, UK and Leipzig University, Germany; João Pedro de Magalhães, University of Liverpool, UK; Kelsey Moody, Ichor Therapeutics, USA; Kevin Perrott, Buck Institute, USA; Matthew O'Connor, SENS Research Foundation, USA.

Link: http://www.longecity.org/forum/page/index.html/_/feature/labs

Coverage of the Caenorhabditis Intervention Testing Program

As you may be aware, a faction at the National Institute on Aging has for some years run the Interventions Testing Program (ITP). The objective is to pick out methods shown in the past to extend life span in mice, and rigorously rerun those studies in order to obtain gold standard data that definitively proves or disproves effects on aging. Unfortunately the budget extends no further than a couple of interventions each year, and the focus is on paths that can do no more than modestly slow aging at best. It should really be considered an adjunct effort to the primary goal of mapping metabolism, not an effort to make meaningful inroads into producing treatments for aging as a medical condition.

Motivations to one side, the need for such a gold standard program in aging studies is evident from the fact that so many claims of slowed aging in mice put forward in past decades cannot be reproduced. A common culprit is calorie restriction; in a way it is a pity that calorie restriction has such a large effect on health and aging. It means that many, many studies have been poisoned over the years, the data made useless because the authors failed to control for calorie intake in the animals involved. Even mild inadvertent calorie restriction produces effects that outweigh many others, and have caused researchers to draw entirely incorrect conclusions, misdirecting further research.

Still, to be honest, this doesn't matter much when it comes to the production of therapies at the end of the day. Rejuvenation treatments worth pursuing are highly unlikely to emerge from this part of the field, that concerned with calorie restriction mimetics, marginal slowing of aging via neutraceuticals, and the like. That could all vanish tomorrow and little of value would be lost; rejuvenation will emerge instead from the SENS repair-based approach, an entirely different area of research and development. However, these efforts to modestly slow aging in mice do matter for the researchers who are attempting to map the progression of aging at the detail level, a vast project proceeding hand in hand with efforts to map all of cellular metabolism. Methods of slowing aging are an important tool from that perspective, a way to identify areas of cellular biochemistry for further investigation. Given that this work is very slow and very expensive, false starts and mistaken directions have a large cost.

The problem of inadequate reproducibility is universal in the life science community, not just in mice and not just in aging research, but for today let us consider that in particular it is a challenge when running studies of aging in the nematode worm Caenorhabditis elegans. A great many such studies take place in comparison to the much more expensive undertaking of a mouse study of aging. Most investigations of the biochemistry of aging start in yeast and nematodes precisely because it is so much cheaper and faster than working with even short-lived mammals. The economics make sense, even accounting for the fact that a fair portion of the findings fail to prove relevant to mammals. Wasting time is wasting time, however, and so it also makes sense to create a Caenorhabditis Intervention Testing Program, analogous to the NIA Interventions Testing Program in mice.

In search for the fountain of youth, a lesson in doing good science

The study promised to be a big step toward cracking the code of aging: In 2000, scientists reported that giving roundworms a compound that blunted the effects of oxygen on their cells could boost their lifespans by 44 percent. After publishing their paper, team leader Gordon Lithgow recalls, "We felt our work had moved the field on into seriously thinking about chemical slowing of aging." But soon after, they started getting phone calls from another lab. Researchers led by David Gems couldn't get the same results, no matter what they tried. And in 2003, they published a paper saying so. That dashing of hopes was "exceedingly disappointing."

But the story has a happy ending, one that illustrates the way science works best. The experience jolted Lithgow to join with researchers around the United States to standardize testing of potential anti-aging compounds in roundworms. That project, known as the Caenorhabditis Intervention Testing Program (CITP), has led to its first results published this week: that, in carefully controlled side-by-side testing, most "fountain-of-youth" chemicals gave mixed results at best, but one drug did in fact extend the worms' lifespan. The impetus to form the CITP was the realization that Lithgow wasn't alone. Once, it was antidepressants that researchers said could extend lifespan. Not according to follow-up studies by other labs, though. The same thing happened with compounds known as sirtuins. So what was going on? One possible answer was that "nothing works in Europe," Lithgow told a laughing audience at a Buck Institute conference in August. "The other possible conclusion … is that we don't really know what we're doing here."

So Lithgow's lab catalyzed the beginnings of the CITP, joining forces with others to test 21,000 worms from 22 strains, just to see whether their lifespans - untreated - were consistent. They weren't. The lifespans of roundworms turn out to vary greatly, even within labs. In fact, the largest variation was when the same researchers repeated experiments. Suddenly, it made sense that testing the same compound on what seemed like the same worms would lead to a different result: The worms weren't identical after all. Armed with that information, Lithgow and his colleagues started doing things differently.

Longevity-promoting superstar gets revealed in Caenorhabditis reproducibility project

"The goal of the CITP is to identify pro-longevity chemicals that are effective across diverse genetic distances making them excellent candidates for trials in more complex animals, including mammals," said Gordon Lithgow, PhD, a professor at the Buck Institute for Research on Aging and a senior author of the paper. Lithgow runs the Buck lab that in 2011 showed that Thioflavin T extended lifespan in healthy nematode worms by more than 50 percent and slowed the disease process in worms engineered to mimic aspects of Alzheimer's disease. "Running experiments in three discrete laboratories allowed us to demonstrate the reproducibility of our study with Thioflavin T. But it's important to note that some of our other compounds did not pass this stringent test - getting feedback on the 'fails' also furthers the larger effort."

Researchers characterized the lifespans of 22 Caenorhabditis strains spanning three species. Thioflavin T was found to be the most robust pro-longevity chemical, as it extended the lifespan of all strains tested. In addition, researchers found that six out of the ten pro-longevity chemicals significantly extended lifespan in at least one strain of Caenorhabditis. Three dietary restriction mimetics were mainly effective across strains of C. elegans but showed more variable responses in other species. "Nearly 100,000 worms were individually monitored during this initial project. We hope that the scope and focus of this project will give confidence that our consortium can identify promising compounds for further testing on aging. The genetic differences between the three species of Caenorhabditis utilized by the CITP were vast - they were comparable to the differences between mice and humans. Aging is a variable process. Identifying compounds that promote longevity across all of those species increases the odds that we are hitting pathways common to many animals, including humans. These are the ones that warrant further exploration."

"Reproducibility has been a sticking point in aging research. Compounds that significantly extend lifespan in simple organisms make a big splash in a journal, only to come under question when results can't be duplicated in other labs. I look back at earlier studies and I think many different labs were working in different strains of worms and using different methods. While mouse studies are an essential part of pre-clinical research, they are also expensive to do. Our hope is that the CITP will yield robust and reproducible candidates that will help fuel success in higher organisms, including humans, where these compounds might be candidates for drugs to combat chronic diseases."

Calorie Restriction Slows Amyloid Accumulation in Mice

The practice of calorie restriction is shown to slow the progression of aging and extend healthy life in most species and lineages tested to date, including non-human primates. In humans the degree of life extension is a question mark, as the available data is exceedingly sparse, but the short-term changes are both very beneficial and very similar to those seen in other mammals. Given this, it should be unsurprising to find that calorie restriction slows any one particular aspect of aging, as is the case here for amyloid accumulation in tissues, one of the root causes of age-related disease and dysfunction in normal individuals, but also a prominent feature in a number of genetic diseases. As is frequently true of studies of calorie restriction, the sweeping changes created in the operation of metabolism make it very challenging to determine root causes and chains of cause and effect for the benefits produced, even when those benefits are clear, evident, and robustly reproducible.

Amyloidosis is a group of diseases characterized by extracellular or intracellular deposition of insoluble amyloid fibrils. Fibrils are formed when normally soluble proteins aggregate due to conformational changes caused by various mechanisms. Amyloid fibrils and oligomers of aggregates cause profound dysfunction in both cells and tissues, and these lead to a number of diseases. Apolipoprotein (Apo) A-II is the second most abundant apolipoprotein in serum high-density lipoprotein (HDL) in humans and mice. We found that ApoA-II accumulates to form amyloid fibrils (AApoAII) that deposit extracellularly in various organs with aging. In humans, it is due to a mutation in the normal stop codon in the ApoA-II gene and it has been observed mainly in the kidneys. In aged mice of many strains, it has been observed systemically in several organs. ApoA-II amino acid sequences of humans and mice differ by approximately 40% and they exist in different forms. However, both ApoA-II proteins exist mainly in HDL particles and they may have similar roles.

We have reported that administration of a very small amount of AApoAII fibrils markedly accelerated amyloid deposits in young mice. Intriguingly, our recent studies have suggested that AApoAII amyloidosis was transmissible by a prion-like infectious process through a seeding-nucleation mechanism. These findings have suggested that mouse AApoAII amyloidosis is an extremely useful model for the analysis of systemic amyloidoses and the development of new preventive treatments for amyloidoses. Nutritional control and caloric restriction (CR) may be the most readily available treatment to prevent or slow these amyloidoses. In particular, CR, i.e., a ~60% reduction of intake compared to an ad libitum (AL) diet, has been reported to be the most effective non-genetic treatment to decelerate aging and extend life- and health-span.

The molecular mechanisms by which longevity is promoted by CR intervention are complex. One important metabolic reaction mediated by CR is autophagy. This process supplies organisms with nutrients via the cytoplasmic recycling system. It also maintains damaged organelles and proteins during aging and increases longevity. The underlying mechanisms by which CR treatment mitigates Alzheimer's disease are suggested by a number of observations. First, both circulating insulin and insulin signaling are altered by CR treatment, enhancing the degradation of amyloid-β via enzymatic processes. Second, CR treatment activates sirtuin-1 (SIRT1) signaling and enhances the function of non-amyloidogenic processing enzyme of the amyloid precursor protein. Third, autophagy induced by CR treatment appears to suppress the progression of Alzheimer's disease. In this regard, there are two reports that demonstrated that activated autophagy degraded amyloid fibrils or reduced levels of amyloid-β peptide and amyloid precursor protein.

In AApoAII amyloidosis, we previously reported that chronic CR (60% caloric intake compared with an AL group) decelerated the advancement of senescence in SAMP1 mice and inhibited the spontaneous deposition of AApoAII fibrils with aging. However, the mechanisms reducing amyloidosis were unclear. Here, we hypothesize that CR treatment does indeed play a preventive role against the progression of systemic amyloidosis. Moreover, we demonstrate that CR treatment reduced the progression of amyloidosis in mice with inducible systemic AApoAII amyloidosis. We suggest that suppressing the levels of amyloid precursor proteins in the body might be a good first step in preventing amyloid deposition in almost all amyloidoses. From our data, CR treatment might lessen amyloid deposition by reducing oxidative stress and improving the unfolded protein response. These results suggested that the beneficial effects of CR are indeed complex. It is currently difficult to pinpoint the direct effects of CR that suppress amyloid deposition.

Link: http://dx.doi.org/10.1371/journal.pone.0172402

An Interesting Study on Aggregates in Aged Tissues

The paper here provides an interesting perspective on the formation of solid aggregates of misfolded or damaged proteins with age, one of the distinguishing features of old tissues. There are numerous types of such aggregate, varying by tissue, and a mix of evidence for their contribution to specific aspects of aging or specific age-related diseases. In some cases it is hard to draw a direct line between a form of aggregate and its consequences. In others the chain of cause and effect is comparatively well understood, as is the case for Alzheimer's disease, amyloid-β, and tau, for example. It seems clear that the fastest way to proceed in each case is build a method to remove the aggregate and then observe the outcomes, both for the goal of increased understanding, and the arguably more important goal of removing causes of aging in order to produce rejuvenation therapies.

Deaths from atherosclerotic cardiovascular disease (CVD) comprise 31% of all mortality worldwide. Age and hypertension are the major risk factors for atherosclerotic CVD, and both are associated with increased stiffness of the heart. This rigidity, resulting in diastolic dysfunction, is largely attributed to myofibroblast growth and collagen deposition between cardiomyocytes. Most proteins adopt, either spontaneously or with the help of other proteins, specific folded structures with limited degrees of freedom. Chemically altered or misfolded structures, when they occur, are vulnerable to aggregation with other unstructured proteins. Although protein damage and misfolding are inevitable, multiple proteostasis systems are devoted to the repair or clearance of damaged proteins. The heart, in particular, is subject to continuous mechanical and metabolic stress; as a result, the cardiac proteome may be especially reliant on multi-level quality control to ensure proper folding and integrity of proteins.

Although protein aggregation has been studied extensively in neurodegenerative diseases, aggregates that form during normal cardiac aging or sporadic CVD have not previously been characterized. In this study, we isolated and quantified compact aggregates from the hearts of young-adult and aged mice and identified their protein constituents. To ask whether the hypertensive state itself disrupts proteostasis and thus mimics aging, we compared protein aggregates from hearts of young mice that were either hypertensive or normotensive. We also examined protein aggregation in early- and late-passage cardiac myofibroblasts, to assess whether their proteostasis is impaired during in vitro senescence and thus may contribute to cardiac senescence in vivo.

Detergent-insoluble protein aggregates were isolated from mouse hearts and characterized on 2-dimensional gels. Their levels increased markedly and significantly with aging and after sustained angiotensin II-induced hypertension. Of the aggregate components identified by high-resolution proteomics, half changed in abundance with age (392/787) or with sustained hypertension (459/824), whereas 30% (273/901) changed concordantly in both. One fifth of these proteins were previously associated with age-progressive neurodegenerative or cardiovascular diseases, or both (eg, ApoE, ApoAIV, clusterin, complement C3, and others involved in stress-response and proteostasis pathways). Because fibrosis is a characteristic of both aged and hypertensive hearts, we posited that aging of fibroblasts may contribute to the aggregates observed in cardiac tissue. Indeed, as cardiac myofibroblasts "senesced" (approached their replicative limit) in vitro, they accrued aggregates with many of the same constituent proteins observed in vivo during natural aging or sustained hypertension.

In summary, we have shown for the first time that compact (detergent-insoluble) protein aggregates accumulate during natural aging, chronic hypertension, and in vitro myofibroblast senescence, sharing many common proteins. Thus, aggregates that arise from disparate causes (aging, hypertension, and replicative senescence) may have common underlying mechanisms of accrual.

Link: https://doi.org/10.1161/HYPERTENSIONAHA.115.06849

Evidence for Gut Microbes to Speed Amyloid Buildup in Alzheimer's Disease

A great diversity of microbial life dwells inside us all, largely in the gut, and these microbes interact with our tissues and immune system in ways that the research community has only recently started to map in earnest. There are a handful of obvious and sometimes very serious medical conditions caused by the presence and inappropriate behavior of forms of microbe in the gut, but beyond this even the more common species are clearly an important component of the body as a whole. They play as great a role as many individual organs in determining health and pace of aging, one slice of the myriad complex interactions that take place constantly between the surrounding environment and various bodily systems.

One of the more direct paths by which the microbiome of the gut can affect long-term health is via its interactions with the immune system. The degree to which the immune system declines with age is in part a function of its exposure to pathogens and other, similar circumstances, and the more of that taking place the worse off you'll be by the time old age rolls around. It is also a matter of the degree to which the immune system is constantly active, however, due to the rising levels of chronic inflammation that accompany old age. Gut microbes can certainly trigger greater inflammation at any age, to some degree, and over time that is thought to add up. Most age-related conditions are accelerated in their progression by inflammation, both via its impact on immune function and via other mechanisms. Among these is Alzheimer's disease and its association with misfolded protein aggregates in the brain: amyloid and tau. Levels of amyloid and tau in the brain are at least somewhat determined by the efficiency with which the immune system can dispose of the unwanted excess, but other links with the inflammatory state of the brain's immune system are also well demonstrated.

So all that said, the open access paper linked below fits into the bigger picture fairly well. Working with mice, the authors provide evidence for differing constituents of the gut microbiome to contribute to the progression of Alzheimer's disease, or at least to the observed levels of amyloid in the brain. While interesting, I think that the likely outcome of applying this knowledge to human medicine is probably incremental at best, let us say along the lines of the impact of excess fat tissue, or poor diet, and probably overlapping with both of those in the mechanisms involved. Tinkering with gut microbes isn't the path to a cure for Alzheimer's disease or other conditions involving the accumulation of damaged proteins in the brain. A cure must, by necessity, involve clearing out the damage comprehensively, which will require a more sophisticated approach to therapies.

Reduction of Abeta amyloid pathology in APPPS1 transgenic mice in the absence of gut microbiota

According to the amyloid cascade hypothesis of Alzheimer's disease (AD) pathogenesis, the aggregation and cerebral deposition of amyloid-β (Aβ) peptides into extracellular amyloid plaques is an early and critical event triggering a cascade of pathological incidents that finally lead to dementia. Thus, arguing in favor of this hypothesis, the most rational strategy for an AD therapy would be to retard, halt and even reverse Aβ aggregation. However, despite all research efforts there is currently no treatment for AD, and currently approved therapies only provide symptomatic treatments for this disease.

Numerous studies indicate that microbial communities represent an essential factor for many physiological processes including nutrition, inflammation, and protection against pathogens. The microbial community is largely composed of bacteria that colonize all mucosal surfaces, with the highest bacterial densities found in the gastrointestinal tract. Increasing evidence suggests the gastro-intestinal tract is the bridge between microbiota and the central nervous system. Clinical and experimental evidence suggests that gut microbiota may contribute to aging and influence brain disorders. Recently, a study revealed an association of brain amyloidosis with pro-inflammatory gut bacteria of cognitively impaired patients. Furthermore, a recent study showed that antibiotic-mediated perturbations in the gut microbiome modulates amyloid deposition in an AD mouse model. While such findings strongly suggest that the gut microbiota may impact a wide range of brain disorders including AD, the impact of complete depletion of intestinal microbes on AD pathogenesis is unknown.

Despite clinical and experimental evidence implicating the intestinal microbiota in a number of brain disorders, its impact on Alzheimer's disease is not known. To this end we sequenced bacterial 16S rRNA from fecal samples of Aβ precursor protein (APP) transgenic mouse model and found a remarkable shift in the gut microbiota as compared to non-transgenic wild-type mice. Subsequently we generated germ-free APP transgenic mice and found a drastic reduction of cerebral Aβ amyloid pathology when compared to control mice with intestinal microbiota. Importantly, colonization of germ-free APP transgenic mice with microbiota from conventionally-raised APP transgenic mice increased cerebral Aβ pathology, while colonization with microbiota from wild-type mice was less effective in increasing cerebral Aβ levels. Our results indicate a microbial involvement in the development of Abeta amyloid pathology, and suggest that microbiota may contribute to the development of neurodegenerative diseases.

Our results showing reduced microgliosis and changes in the brain cytokine profile are in line with a recent publication demonstrating that germ-free mice show immature microglia and reduced pro-inflammatory cytokine production. Importantly, caspase-1 knockout (which prevents the production of IL-1β) has been shown to be sufficient to strongly reduce plaque load in APPPS1 animals through altering the microglial activation state and enhancing microglial phagocytosis of Aβ plaques. Therefore, a change in microglial responses in germ-free APPPS1 animals could contribute to the reduction of amyloid load observed in germ-free animals. Several in vitro and in vivo studies have shown that neprilysin (NPE) and insulin degrading enzymes (IDE) can degrade Aβ. Most notably, NPE and IDE levels were increased in germ free APPPS1 mice, indicating that increased levels of these Aβ degrading enzymes may contribute to decreased cerebral Aβ amyloidosis in germ free animals. Altogether, these results indicate that Aß degrading enzymes may partially play a role in decreasing Aβ levels and cerebral Aß amyloidosis in germ free animals.

The Basis for an Antibody Therapy to Treat Transthyretin Amyloidosis

Misfolded transthyretin accumulates with age, forming solid amyloid deposits in tissues, particularly in the cardiovascular system. Amyloid disrupts proper function of cells and organs, and this is likely the majority cause of death in supercentenarians, the oldest humans. In recent years evidence has emerged for transthyretin amyloid to be involved in heart failure and a range of other conditions in younger old age, as well. There are a number of different approaches to clearing transthyretin amyloid under development, one of which has had a successful human trial, but progress towards the clinic is nonetheless exceedingly slow. This is disappointing, as this sort of therapy is a form of narrow rejuvenation, beneficial to every adult, and should not be locked up within the regulatory system in this way. Those developing and funding these treatments have to date failed to appreciate the true scope of success, or they would be far more eager to move ahead.

Transthyretin amyloidosis (ATTR amyloidosis) is caused by the misfolding and deposition of the transthyretin (TTR) protein and results in progressive multi-organ dysfunction. TTR epitopes exposed by dissociation and misfolding are targets for immunotherapeutic antibodies. We developed and characterized antibodies that selectively bound to misfolded, non-native conformations of TTR. Antibody clones were generated by immunizing mice with an antigenic peptide comprising a cryptotope within the TTR sequence and screened for specific binding to non-native TTR conformations, suppression of in vitro TTR fibrillogenesis, promotion of antibody-dependent phagocytic uptake of misfolded TTR and specific immunolabeling of ATTR amyloidosis patient-derived tissue.

Four identified monoclonal antibodies were characterized. These antibodies selectively bound the target epitope on monomeric and non-native misfolded forms of TTR and strongly suppressed TTR fibril formation in vitro. These antibodies bound fluorescently tagged aggregated TTR, targeting it for phagocytic uptake by macrophage THP-1 cells, and amyloid-positive TTR deposits in heart tissue from patients with ATTR amyloidosis, but did not bind to other types of amyloid deposits or normal tissue. These novel antibodies may be therapeutically useful in preventing deposition and promoting clearance of TTR amyloid and in diagnosing TTR amyloidosis.

Link: https://dx.doi.org/10.3109/13506129.2016.1148025

Arguing that it is Immoral to Object to Longevity Science for Fear of Overpopulation

Overpopulation is one of the great apocalyptic fears of our era, and like many of the rest of those fears, it is unfounded. If anything, the trajectory is for increased wealth to reduce population as children shift from being a necessary benefit to what is effectively a form of luxury good. Further, the effects of great longevity on population size are generally much smaller than people imagine, as rigorous modeling shows. Lastly, this planet could support more than ten times the current population using present day technologies, were more of the land used efficiently. Yet still, people look at the results of war and kleptocracy and cry overpopulation rather than recognizing the true causes of suffering.

In this article, I'll try to show that the overpopulation objection against rejuvenation is morally deplorable, that not developing rejuvenation for the sake of avoiding overpopulation is morally unacceptable, and thus overpopulation doesn't constitute a valid objection to rejuvenation. I'll start with an example. Imagine there's a family of two parents and three children. They're not doing too well financially, and they live packed in a tiny apartment with no chances of moving somewhere larger. Clearly they cannot afford having more children, but they would really like having more anyway. What should they do? The only reasonable answer is that they should not have any more children until they can afford having them. Throwing away the old ones for the sake of some other child to be even conceived yet would be nothing short of sheer madness.

That being said, let's have a look at the overpopulation objection. It can be summarised as follows: If we cured ageing, we would end up having more people than our planet can sustain. Therefore we should not cure ageing. Translation: Curing ageing means eliminating age-related diseases as a cause of death, i.e. eliminating a very effective way to get rid of older people. If we don't get rid of older people, we won't have room for new ones, so we shouldn't cure ageing.

If we were to apply this logic to the small-scale example of the family, we should get rid of the older kids to make room for the new ones, and I'm not talking about kicking them out of the house when they're 18; new people are born all the time in the world, which in our small-scale example translates to the family wanting more kids here and now. Not curing ageing means letting people become sick with horrible age-related diseases and die of them; in the small-scale example, this could be compared to not vaccinating the kids. It goes without saying that, from a merely moral standpoint, if we're afraid that we might end up having more people than we can afford having, the appropriate answer to this problem is 'let's not make more people than we can afford having'.

Still, the idea of present-day people dying for the sake of potential future children who aren't even in their mothers' wombs yet somehow seems perfectly acceptable; however, when applied the example of the family, the very same idea appears to be a clear case of being several sandwiches short of a picnic. Why this double standard? I can think of three reasons. The first, obvious reason is that death by ageing happens 'naturally' and up until now has been inevitable, so by the false equation 'normal'='right', people conclude this is how things should be. The second reason might be that we don't value elderly lives as much as children's. This may be understandable from the cynical survival-of-the-species point of view, but is absolutely undefendable from any humane point of view. The third reason is that we don't really think of humanity as some sort of big family. The children of the family example are much more 'concrete' than the elderly people of the large-scale example. When you think of the former, you identify with one of the parents and are horrified at the thought of throwing away your own children; when you think of the latter, for the most part they're just random elderly people whom you don't know and have no emotional attachment to.

Long story short: You can't use overpopulation as a reason to object to rejuvenation biotechnologies, because you can't ask people to give up on good health and potentially indefinite lifespans for the sake of people who aren't even in the making yet. The only reasonable alternative is that we don't make more people than we can afford having.

Link: https://rejuvenaction.wordpress.com/answers-to-objections/objections-to-rejuvenation/rejuvenation-would-cause-overpopulation/moral-implications/

Induced Pluripotency as a Tool to Enable Rejuvenation of Blood Production

It has been a decade or so since the first induced pluripotent stem (iPS) cells were produced. Researchers discovered a recipe by which ordinary, limited, adult somatic cells could be reprogrammed into a state near identical to that of embryonic stem cells, meaning they are pluripotent and can then in principle be used to produce any of the cell types in the body. Doing so in practice requires researchers to establish a suitable methodology to guide cellular differentiation in the right direction, only accomplished at this point for a fraction of all possible cell types. The early attempts at induced pluripotency worked, and were easy to set up, but were also comparatively inefficient. Since then researchers have produced considerable improvement in the methodologies used, and along the way have explored other facets of this reprogramming process. One of the most intriguing aspects of induced pluripotency is that it appears to produce a form of cellular rejuvenation, a sweeping reset and repair of many forms of damage.

There are many open questions regarding this incompletely explored cellular rejuvenation achieved through induced pluripotency: how it works at the detail level; exactly which types of damage are repaired and which are not; how it relates to the equivalent process that occurs in the early development of the embryo. How do old gamete cells, laden with the molecular damage of aging, produce young offspring who lack that damage? Somewhere in there, rejuvenation happens. Is there any way to adapt this process of rejuvenation for use in therapies? It seems unwise to, for example, apply pluripotency reprogramming methods directly to a patient. This sounds a lot like opening the door to a high risk of uncontrolled cellular replication, or cancer in other words. Nonetheless, that experiment was recently carried out in mice, more or less, so we'll likely hear more about the risks in the years ahead. It is possible that such an approach will in the end fall into the same ballpark as stem cell therapies when it comes to overall degree of risk, though it is worth noting that, when performed improperly, stem cell therapies can also result in cancer, and considerable amount of work has gone into minimizing that outcome in those therapies that have made it to widespread clinical availability.

There are other possibilities when it comes to using the rejuvenation that occurs during the induced pluripotency process, however. Take a population of cells that are damaged and dysfunctional in an old individual, for example. Obtain a sample, create an induced pluripotent lineage from that sample, and then apply a suitable recipe to differentiate the pluripotent cells back into the original cell type. Do these recreated cells now behave as though they are younger, and can thus form the basis for a cell therapy to replace the old cells in the patient? Researchers here demonstrate that this is in fact the case for the stem cells responsible for generating blood:

How blood can be rejuvenated

When we are young, our blood stem cells produce an even and well-balanced number of red and white blood cells according to need. As we age, however, the capacity of the blood stem cells to produce the number of blood cells we need declines. "This type of age-related change can have major consequences as it can lead to an imbalance in stem cell production. For example, a reduced production of immune cells or excessive production of other types of cells can be a precursor to leukaemia."

A fundamental question was whether blood stem cells age differently within a single individual or whether all blood stem cells are equally affected by advancing age. In an initial stage, it was therefore important to genetically mark old blood stem cells, to enable the identification and tracking of those most affected by age. In the next step, these traceable cells were reprogrammed to another type of stem cell - known as iPS cells, which can generate all cells in an individual and not only blood cells. When the cells are reprogrammed, their identity is "re-set"; when these reprogrammed iPS cells formed new blood stem cells, the researchers observed that the re-set had entailed a rejuvenation of the cells. "We found that there was no difference in blood-generating capacity when we compared the reprogrammed blood stem cells with healthy blood stem cells from a young mouse. This is, as far as we know, the first time someone has directly succeeded in proving that it is possible to recreate the function of young stem cells from a functionally old cell.ˮ

The research team's studies have also thereby shown that many age-related changes in the blood system cannot be explained by mutations in the cells' DNA. If the changes depended on permanent damage at the DNA level, the damage would still be present after the re-set. Instead, epigenetic changes appear to underlie the decline in function associated with advancing age.

Clonal reversal of ageing-associated stem cell lineage bias via a pluripotent intermediate

While age-related diseases evidently can arise due to changes that compromise or alter the function of mature effector cells, this is harder to reconcile with organs such as the blood, that rely on inherently short-lived effector cells in need of continuous replenishment. Rather, accumulating data have suggested that the de novo production of subclasses of haematopoietic cells shifts in an age-dependent manner, akin to that seen during more narrow time windows in early development. These findings have to a large extent also challenged the classically defining criteria of haematopoietic stem cells (HSCs) as a homogenous population of cells with differentiation capacity for all haematopoietic lineages. Rather, the differentiation capacity of HSCs might be more appropriately defined by a continuous multilineage haematopoietic output, but which might not necessarily include the production of all types of blood cells at all points in time.

The mechanisms that drive ageing at both the organismal and cellular level have attracted significant attention as they represent prime targets for intervention. An increased function of aged cells by 'young'-associated systemic factors has been proposed. Whether such approaches indeed reflect rejuvenation at a cellular level or rather stimulate cells less affected by age is mostly unclear. This concern applies also to previous studies approaching the prospects of reversing cellular ageing by somatic cell reprogramming, which have typically failed to distinguish between functionally versus merely chronologically aged cells.

Here we approach these issues by genetic barcoding of young and aged HSCs that allows for evaluations, at a clonal level, of their regenerative capacities following transplantation. This allows us to establish that ageing associates with a decrease of HSC clones with lymphoid potential and an increase of clones with myeloid potential. We generate induced pluripotent stem (iPS) lines from functionally defined aged HSC clones, which we next evaluate from the perspective of their blood-forming capacity following re-differentiation into HSCs by blastocyst/morula complementation. Our experiments reveal that all tested iPS clones, including such that were originally completely devoid of T-cell and/or B-cell potential, perform similar to young HSCs both in steady-state and when forced to regenerate lymphomyeloid haematopoiesis in secondary transplantations. This regain in function coincides with transcriptional features shared with young rather than aged HSCs. Thereby, we provide direct support to the notion that several functional aspects of HSC ageing can be reversed to a young-like state.

Working on a Drug to Stimulate Regeneration of Lost Hair Cells in the Inner Ear

One class of the numerous forms of age-related deafness is caused by loss of hair cells in the inner ear. These cells are a necessary part of the chain of systems that leads from sound outside the body to signals passing along nerves into the brain for interpretation. As these hair cells are lost, so is hearing capacity. A range of efforts to reverse this loss are underway at various stages of development, such as reprogramming a cell sample into patient-matched hair cells, or, as in this case, finding ways to provoke regeneration in situ, changing cellular behavior so that they rebuild where they would normally not do so.

Within the inner ear, thousands of hair cells detect sound waves and translate them into nerve signals. Each of us is born with about 15,000 hair cells per ear, and once damaged, these cells cannot regrow. Noise exposure, aging, and some antibiotics and chemotherapy drugs can lead to hair cell death. In some animals, those cells naturally regenerate, but not in humans. However, researchers have now discovered a combination of drugs that expands the population of progenitor cells (also called supporting cells) in the ear and induces them to become hair cells, offering a potential new way to treat hearing loss.

The research team began investigating the possibility of regenerating hair cells during an earlier study on cells of the intestinal lining. In that study, researchers reported that they could generate large quantities of immature intestinal cells and then stimulate them to differentiate, by exposing them to certain molecules. During that study, the team became aware that cells that provide structural support in the cochlea of the ear express some of the same surface proteins as intestinal stem cells. The researchers decided to explore whether the same approach would work in those supporting cells.

They exposed cells from a mouse cochlea, grown in a lab dish, to molecules that stimulate the Wnt pathway, which makes the cells multiply rapidly. At the same time, to prevent the cells from differentiating too soon, the researchers also exposed the cells to molecules that activate another signaling pathway known as Notch. Once they had a large pool of immature progenitor cells, the researchers added another set of molecules that provoked the cells to differentiate into mature hair cells. This procedure generates about 60 times more mature hair cells than the technique that had previously worked the best, which uses growth factors to induce the supporting cochlea cells to become hair cells without first expanding the population.

The researchers found that their new approach also worked in an intact mouse cochlea removed from the body. In that experiment, the researchers did not need to add the second set of drugs because once the progenitor cells were formed, they were naturally exposed to signals that stimulated them to become mature hair cells. "We only need to promote the proliferation of these supporting cells, and then the natural signaling cascade that exists in the body will drive a portion of those cells to become hair cells." Because this treatment involves a simple drug exposure, the researchers believe it could be easy to administer it to human patients. They envision that the drugs could be injected into the middle ear, from which they would diffuse across a membrane into the inner ear.

Link: http://news.mit.edu/2017/drug-treatment-combat-hearing-loss-0221

Senescent Cells Implicated as a Cause of Idiopathic Pulmonary Fibrosis

The number of senescent cells in tissues grows with age, and these cells cause harm through forms of signaling that induce inflammation, destructively remodel the extracellular matrix, and alter the behavior of other cells for the worse. Now that clearance of senescent cells has been shown to robustly extend healthy life span in mice, there is a lot more interest in the research community in joining the dots between cellular senescence and specific age-related diseases. The past year has seen a range of publications that directly implicate senescent cells in various age-related diseases, or attempt to quantify exactly how much of the detrimental alterations in aged tissues are caused by these cells. In this particular case, researchers are looking at the lung condition known as idiopathic pulmonary fibrosis, and you might compare these results with another promising study of senescent cells in the lungs carried out last year. We can hope that the various companies developing clearance therapies will bring them to the clinic sooner rather than later.

A study has shown evidence linking the biology of aging with idiopathic pulmonary fibrosis, a disease that impairs lung function and causes shortness of breath, fatigue, declining quality of life, and, ultimately, death. Researchers believe that these findings are the next step toward a possible therapy for individuals suffering from idiopathic pulmonary fibrosis. "Idiopathic pulmonary fibrosis is a poorly understood disease, and its effects are devastating. Individuals with idiopathic pulmonary fibrosis express difficulty completing routine activities. There are currently no effective treatment options, and the disease leads to a dramatic decrease in health span and life span, with life expectancy after diagnosis between three to five years."

Researchers studied the lung tissue of healthy individuals and of persons with mild, moderate and severe idiopathic pulmonary fibrosis. Researchers found that the markers of cellular senescence, a process triggered by damage to cells and linked to aging, were higher in individuals with idiopathic pulmonary fibrosis, and senescent cell burden increased with the progression of the disease. Then, they demonstrated that factors secreted by senescent cells could drive inflammation and aberrant tissue remodeling and fibrosis, which are hallmarks of idiopathic pulmonary fibrosis. "Up to this point, research efforts have largely focused on understanding the unique elements that contribute to idiopathic pulmonary fibrosis. Here, we are considering whether the biology of aging is accelerated in this aggressive disease. What we've found is that senescent cells are prevalent, secreting toxic molecules that affect healthy cells in that environment and are essentially promoting tissue fibrosis."

Equipped with the findings from their studies of human lung tissue, researchers then replicated the process in mice. They found that, much like in humans, mice with clinical features of idiopathic pulmonary fibrosis also demonstrated increased amounts of senescent cells. Researchers used a genetic model programmed to make senescent cells self-destruct and a drug combination of dasatinib and quercetin which, in previous studies, was shown to eliminate senescent cells. Results showed that clearing senescent cells from unhealthy mice improved measures of lung function and physical health, such as exercise capacity on a treadmill. "We are exploring whether senolytic drugs, or drugs that can selectively kill senescent cells, can be used for the treatment of aging-associated conditions, including idiopathic pulmonary fibrosis. More research is needed to validate this, and our goal is to move quickly from discovery to translation to application, and, ultimately, meet the unmet needs of our patients."

Link: http://newsnetwork.mayoclinic.org/discussion/mayo-clinic-researchers-discover-link-between-aging-devastating-lung-disease/

Towards Therapies Capable of Reversing the Progression of Fibrosis

Fibrosis is a significant component of many age-related conditions, a failure of the normal regenerative process that leads to the formation of increasing amounts of scar-like, fibrous connective tissue in organs. This disrupts normal tissue structure and degrades proper function. It features prominently in common forms of heart disease, kidney failure, and liver disease, among others. As is the case for many specific aspects of aging, there is no good treatment for fibrosis, if by this we mean a reliable way to turn back its progression and restore failing tissues to their former state.

The causes of fibrosis lie somewhere downstream of the fundamental forms of cell and tissue damage outlined in the SENS view of aging. Insofar as it is cells that work to produce fibrotic structures, built from the same materials as the normal extracellular matrix, the proximate causes of fibrosis are thus altered cell signaling and behavior, such as that related to the increased chronic inflammation that accompanies aging. The nature of these signals is much debated, and likely varies considerably from tissue to tissue.

Given the importance of fibrosis to the progression of age-related disease, there is considerable interest in finding ways to reverse its progression, not just slow it down. Most such research, as is the case in the paper linked below, is focused on the proximate causes of fibrosis, the altered cellular signaling and behavior. Researchers hope that by forcing a change here, through the use of small molecule drugs and the like, they can change cellular behavior for the better despite the continued existence of underlying damage that causes dysfunction, and set cells to removing fibrosis and correctly regenerating tissue. Or at last tilt the balance somewhat in that direction.

Peptide reverses cardiac fibrosis in a preclinical model of congestive heart failure

Cardiac fibrosis, an abnormal thickening of the heart wall leading to congestive heart failure, was not only halted but also reversed by a caveolin-1 surrogate peptide (CSD) in a preclinical model, report researchers. CSD was able to decrease the fibrotic ventricular wall thickness and improve heart function, all with apparently no toxicity and minimal off-target effects. More than a decade ago, researchers noted that the skin and lung cells producing excess collagen in scleroderma, leading to fibrosis, were deficient in caveolin-1. Supplementing these cells with a caveolin-1 surrogate peptide (CSD; caveolin-1 scaffolding domain peptide), a truncated version of the original compound, showed a reversal of fibrosis.

Hypertrophic overgrowth and profibrogenic signaling of the cardiac muscle occurs under pressure overload. Fibrosis that develops under these conditions is detrimental to the heart's pumping efficiency as it causes a stiffer and less compliant cardiac muscle, leading to the progression of congestive heart failure. To mimic the cardiac fibrosis typical of heart failure, researchers used a transverse aortic constriction mouse model to create pressure overload hypertrophy that then led to the development of fibrosis. Treatment with CSD not only halted the progression of the cardiac fibrosis but also led to its reversal with improved ventricular function.

Although promising, these findings are preliminary - only reflecting outcomes in mice. The researchers plan to run larger preclinical studies using the same approach to generate more definitive data, and if all goes as expected, to move forward to the large-animal studies necessary to take a compound forward into clinical trial. They also note that they are testing CSD in a different congestive heart failure model, the angiotensin II infusion model, which also affects the kidneys. CSD is showing promising anti-fibrotic effects on both the heart and the kidneys in this model. "Fibrotic diseases are related to each other no matter the affected organ. In our case, we were studying lung and skin fibrosis. We had the opportunity to test the same reagent in heart fibrosis and, lo and behold, it worked even better than in lung and skin fibrosis models. And there are plenty of other diseases with a fibrotic element to them where we think the CSD peptide might be useful."

Reversal of maladaptive fibrosis and compromised ventricular function in the pressure overloaded heart by a caveolin-1 surrogate peptide

Chronic ventricular pressure overload (PO) results in congestive heart failure (CHF) in which myocardial fibrosis develops in concert with ventricular dysfunction. Caveolin-1 is important in fibrosis in various tissues due to its decreased expression in fibroblasts and monocytes. The profibrotic effects of low caveolin-1 can be blocked with the caveolin-1 scaffolding domain peptide (CSD, a caveolin-1 surrogate) using both mouse models and human cells.

We have studied the beneficial effects of CSD on mice in which PO was induced by trans-aortic constriction (TAC). Beneficial effects observed in TAC mice receiving CSD injections daily included: improved ventricular function (increased ejection fraction, stroke volume, and cardiac output; reduced wall thickness); decreased collagen I, collagen chaperone HSP47, fibronectin, and CTGF levels; decreased activation of non-receptor tyrosine kinases Pyk2 and Src; and decreased activation of eNOS. To determine the source of cells that contribute to fibrosis in CHF, flow cytometric studies were performed that suggested that myofibroblasts in the heart are in large part bone marrow-derived. Two CD45+ cell populations were observed. One (Zone 1) contained CD45+/HSP47-/macrophage marker+ cells (macrophages). The second (Zone 2) contained CD45moderate/HSP47+/macrophage marker- cells often defined as fibrocytes. TAC increased the number of cells in Zones 1 and 2 and the level of HSP47 in Zone 2. These studies are a first step in elucidating the mechanism of action of CSD in heart fibrosis and promoting the development of CSD as a novel treatment to reduce fibrosis and improve ventricular function in CHF patients.

Projecting out Current Life Expectancy Trends to 2030

I think it a given that trend projection at the present time is going to greatly underestimate gains in life expectancy over the next few decades. This present decade and the next encompass a transition from palliative and compensatory medicine that inadequately patches over the causes of aging, and a research community that has no interest in treating aging itself as a medical condition, to a field of rejuvenation treatments that do actually address the forms of cell and tissue damage that cause degenerative aging, and a research community that is now very interested in working towards therapies for aging. Past gains have occurred despite the fact that research and development efforts made no attempt to treat root causes in aging. Future gains, produced by those actually trying to address aging, will be larger and occur more rapidly.

A new study analysed long-term data on mortality and longevity trends to predict how life expectancy will change in 35 industrialised countries by 2030. Nations in the study included both high-income countries, such as the USA, Canada, UK, Germany, Australia, and emerging economies such as Poland, Mexico and the Czech Republic. The study revealed all nations in the study can expect to see an increase in life expectancy by 2030. The results also found that South Koreans may have the highest life expectancy in the world in 2030. "The increase in average life expectancy in high income countries is due to the over-65s living longer than ever before. In middle-income countries, the number of premature deaths - i.e. people dying in their forties and fifties, will also decline by 2030."

The team calculated life expectancy at birth, and predicted a baby girl born in South Korea in 2030 will expect to live 90.8 years. Life expectancy at birth for South Korean men will be 84.1 years. The researchers also calculated how long a 65-year-old person may expect to live in 2030. The results revealed that the average 65-year-old woman in South Korea in 2030 may live an additional 27.5 years. Scientists once thought an average life expectancy of over 90 was impossible. "We repeatedly hear that improvements in human longevity are about to come to an end. Many people used to believe that 90 years is the upper limit for life expectancy, but this research suggests we will break the 90-year-barrier. I don't believe we're anywhere near the upper limit of life expectancy - if there even is one."

French women and Swiss men were predicted to have the highest life expectancies at birth in Europe in 2030, with an average life expectancy of 88.6 years for French women and nearly 84 years for Swiss men. The results also revealed that the USA is likely to have the lowest life expectancy at birth in 2030 among high-income countries. The nation's average life expectancy at birth of men and women in 2030 (79.5 years and 83.3 years), will be similar to that of middle-income countries like Croatia and Mexico. The team also predicted a 65-year-old UK man in 2030 could expect to live an additional 20.9 years (12th in the table of countries), while a 65-year-old woman in the UK could expect to live an additional 22.7 years, up (22nd in the table of countries). The research also suggested the gap in life expectancy between women and men is closing. "Men traditionally had unhealthier lifestyles, and so shorter life expectancies. They smoked and drank more, and had more road traffic accidents and homicides. However as lifestyles become more similar between men and women, so does their longevity."

Link: http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_21-2-2017-15-33-52

Is a Clone Born at Age Zero?

In the overlap between research into aging and research into regeneration there is some interest in what exactly it is that happens between fertilization and later development of a zygote that enables old reproductive cells to produce young children. Some form of reset takes place, a clearing out of damage. This is also seen in induced pluripotency, whereby ordinary somatic cells are reprogrammed into a state very similar to that of embryonic stem cells. It is an open question as to whether any part of this natural rejuvenation mechanism can be safely harnessed and turned into a therapy, though it is worth noting that induction of induced pluripotency in the tissues of adult mice has been tried recently. Animal cloning is another line of research that might help to shed light on what happens in early development, a topic that was covered in some depth last year. Do clones age normally, and are they born with a similar level of molecular damage as their natural peers? Why, if so?

In 1997, Dolly the sheep was introduced to the world. The implications of cloning animals in our society were self-evident from the start. Our advancing ability to reprogram adult, already-specialized cells and start them over as something new may one day be the key to creating cells and organs that match the immune system of each individual patient in need of replacements. But what somehow got lost was the fact that a clone was born - at day zero - created from the cell of another animal that was 6 years old. Researchers have spent the past 20 years trying to untangle the mysteries of how clones age. How old, biologically, are these animals born from other adult animals' cells?

When Dolly was cloned, she was created using a cell from a 6-year-old sheep. And she died at age 6-and-a-half, a premature death for a breed that lives an average of nine years or more. People assumed that an offspring cloned from an adult was starting at an age disadvantage. Rather than truly being a "newborn," it seemed like a clone's internal age would be more advanced than the length of its own life would suggest. Thus the notion that clones' biological ages and their chronological ones were out of sync, and that "cloned animals will die young."

Some of us were convinced that if the cloning procedure was done properly, the biological clock should be reset - a newborn clone would truly start at age zero. We worked very hard to prove our point. We were not convinced by a single DNA analysis done in Dolly showing slightly shorter telomeres - the repetitive DNA sequences at the end of chromosomes that "count" how many times a cell divides. We presented strong scientific evidence showing that cloned cows had all the same molecular signs of aging as a nonclone, predicting a normal lifespan. Others showed the same in cloned mice. But we couldn't ignore reports from colleagues interpreting biological signs in cloned animals that they attributed to incomplete resetting of the biological clock. So the jury was out.

Aging studies are very hard to do because there are only two data points that really count: date of birth and date of death. If you want to know the lifespan of an individual you have to wait until its natural death. By 2012 that was in fact being accomplished: there were several cloned Dollies, all much older than Dolly at the time she had died, and they looked terrific. This work was finally published last year. "For those clones that survive beyond the perinatal period, the emerging consensus, supported by the current data, is that they are healthy and seem to age normally."

The new Dollies are now telling us that if we take a cell from an animal of any age, and we introduce its nucleus into a nonfertilized mature egg, we can have an individual born with its lifespan fully restored. They confirmed that all signs of biological and chronological age matched between cloned and noncloned sheep. There seems to be a natural built-in mechanism in the eggs that can rejuvenate a cell. We don't know what it is yet, but it is there. Our group as well as others are hard at work, and as soon as someone finds it, the most astonishing legacy of Dolly will be realized.

Link: http://www.the-scientist.com/?articles.view/articleNo/48571/title/Opinion--Is-a-Clone-Really-Born-at-Age-Zero-/

An Interview with Aschwin de Wolf on Cryonics at LongeCity

Aschwin de Wolf of Advanced Neural Biosciences and the Institute for Evidence-Based Cryonics (IEBC) is a noted advocate for cryonics as an industry and area of research. He was recently interviewed by the folk over at LongeCity, and as usual it makes for interesting reading. You might also look at a 2013 interview for more of the same, and in addition you'll find many articles at the IEBC site covering a mix of technical and non-technical topics in the the cryonics field. This is one slice of a great deal of technical writing and advocacy for cryonics published over the course of the past few decades, a fair portion of it by people who are now themselves cryopreserved at Alcor or the Cryonics Institute.

The term cryonics covers the technology, community, and practice of placing people into a vitrified state as soon as possible following clinical death. Tissues are perfused with cryoprotectant and cooled to liquid nitrogen temperatures in stages, leading to a glass-like state of minimal ice-crystal formation. Under good conditions, this preserves the fine structures of neural tissue, the synapses, dendrites, and dendritic spines within which the data of the mind is thought to be stored. For so long as that data remains intact, and the vitrified individual in low-temperature storage, there is the possibility of future restoration in an era with more proficient technology than our own. In this age of progress, cryonics is a necessary backup plan for those of who may not live long enough to benefit from the near future of rejuvenation therapies after the SENS model. It is a great pity that it remains a small and marginal undertaking, largely non-profit, and unknown to many who would benefit, even as tens of millions march towards their own personal oblivion each and every year.

While higher animals cannot yet be thawed, cleared of cryoprotectant, and brought back to life, that outcome can be achieved with lower animals such as nematode worms. Thawing and transplantation has also been demonstrated in prototype for mammalian organs in recent years. At present there is the makings of a small industry working on reversible cryopreservation for tissue engineering and organ transplantation, where such a technology would greatly reduce costs and simplify logistics. So when we talk about preserving people for the chance at a future restoration, this isn't done in a vacuum, and isn't a flight of fancy; there is good reason to think that there is a chance of success in this endeavor. It certainly beats the odds of revival from the grave, which is to say zero.

Interview with Aschwin de Wolf (February, 2017)

How has the cryopreservation procedure evolved since the first human was placed in cryostasis?

The most important element in the progress of cryopreservation procedures in cryonics is the progressive elimination of ice formation. When cryonics started, patients were often cryopreserved without any cryoprotection or very low concentrations of cryoprotectant. In the 1980's and 1990's organizations such as Alcor started adapting mainstream perfusion technologies to introduce high concentrations of cryoprotectants (such as glycerol) to mitigate ice formation. In 2000 Alcor formally introduced vitrification with the aim of eliminating freezing altogether.

The elimination of ice formation, which can be achieved in good cases, removes one major form of mechanical damage in the cryopreserved brain. One very attractive feature of a low-toxicity vitrification agent like M22 is that it does not require rapid cooling to prevent ice formation. Under good circumstances (no prior ischemia) it can also be used in whole-body patients without edema - a problem that seemed to plague prior DMSO-based cryoprotectants in cryonics. Elimination of ice formation and reduced toxicity has substantially reduced the degree of damage associated with cryopreservation.

Which foreseeable advances in the field of cryobiology do you believe will lead to improvements in cryonics?

I foresee further advances in two areas; a more detailed understanding of the nature of cryoprotectant toxicity and the design of brain-optimized cryoprotectants. Cryoprotectant toxicity is currently the most formidable obstacle preventing reversible cryopreservation of complex mammalian organs. With the exception of the work of Dr. Greg Fahy and his colleagues at 21st Century Medicine, it is rather surprising how little theoretical and experimental research has been done to illuminate the mechanisms of cryoprotectant toxicity. It is also increasingly recognized that the poor penetration of cryoprotectants across the blood-brain barrier causes dehydration of the brain. We need to develop brain-optimized vitrification solutions and/or identify better methods to deliver cryoprotectants to the brain without such significant changes in brain volume. Resolving these two issues will bring us much closer to reversible brain cryopreservation.

What evidence is there that the brain is not damaged by the cryopreservation process to such an extent that the information in it may be lost forever?

To start with, if we can eliminate ice formation in the brain, the damage associated with cryoprotectant toxicity is assumed to be mostly of a biochemical nature (i.e. denatured proteins) and does not alter the ultrastructure of the brain in a way that precludes inferring the original state. Cryoprotectant-induced dehydration of the brain is a little more of a wild card because we do not have much detailed information about the kind of ultrastructural changes associated with it. Hence, the priority to avoid the brain shrinking that is routinely observed in "good" cases. Ultimately, our incomplete knowledge of the neuroanatomical basis of identity, and about the exact capabilities and limits of future medicine, prompt us to be agnostic about the degree of damage that is still compatible with meaningful revival. Advocates of cryonics are sometimes accused of being too optimistic about future science, but perhaps skeptics are too pessimistic.

To our knowledge (which is based on cryobiological studies and theoretical calculations), deterioration of patients stored at cryogenic temperatures should be non-existent or negligible. Things get a little bit more complicated when we store patients at intermediate temperatures instead of liquid nitrogen temperatures. It has been suggested that nucleation may still occur slightly below the temperature where the vitrification solution turns into a glass (-123 degrees Celsius). At that temperature, however, nucleation does not translate into ice formation but it might create more challenging repair and revival scenarios.

Do you have any hypotheses on how the cryoprotectant could be removed from the body during the reanimation procedure and how hypoxic injury during this removal procedure could be prevented?

In the vision of researchers such as Robert Freitas and Ralph Merkle, a mature form of mechanical nanotechnology will be used to conduct the initial stages of repair and cryoprotectant removal at cryogenic temperatures. If this vision of nanotechnology is plausible, cryoprotectant can be removed while providing (local) metabolic and structural support to prevent damage or freezing. An alternative vision of nanomedicine will involve the use of biological repair machines such as modified viruses or modified white blood cells that operate using conventional diffusion-driven chemistry rather than molecular mechanical nanotechnology. Repair is more challenging in this biological scenario because tissue first needs to be warmed to temperatures at which the cryoprotectant solution inside cells and tissue becomes liquid. This risks movement of damaged structures, possible growth of ice, and cryoprotectant toxicity accumulation occurring at the same time as repairs are being made.

Cryogenic storage of genetic mutants is already a common procedure in the roundworm C. elegans. Are you aware of any research taking place that tries to expand cryogenic storage to other model organisms?

Natasha Vita-Moore, who conducted recent studies on the effects of vitrification on memory in C. elegans, has suggested that the next step would be a slightly more complex organism such as the Greenland Woolly Bear Caterpillar or the ozobranchid leech. One of the most common suggestions I get is to attempt suspended animation on a mouse or rat. This would definitely provide powerful proof of principle for the feasibility of human suspended animation, but I do not think that the challenges in achieving reversible biostasis in a small mammal are that much smaller than in humans. We would need to overcome the same obstacles: minimizing cryoprotectant toxicity, chilling injury, dehydration of the brain, ischemia during cooling, and cryoprotective perfusion, etc. The majority opinion in cryonics is to solve these individual problems more thoroughly before attempting reversible cryopreservation of a complete animal.

The Risks of Current Approaches to Rebooting the Immune System

The present approaches to rebooting the immune system have shown considerable promise in treatment of autoimmune diseases such as multiple sclerosis. Unfortunately the current methods of immune destruction involve chemotherapy, which is a damaging process in and of itself, and there is as yet too little attention being given to protection against infection in the period while the immune system is absent or near-completely suppressed. The risks are significant, and until addressed mean that this remains useful only for patients who will suffer worse absent the therapy.

Both of the major risks noted above could be addressed in the near future, however. Firstly through the development of targeted cell destruction methods with minimal side-effects, such as that currently pioneered by Oisin Biotechnologies, and secondly through delivery of new immune cells generated from the patient's own cells. It is in all our interests to see a broadening of immune reboot work, as this class of therapy could help clear out the malfunctioning and misconfigured cells from an age-damaged immune system, producing a partial rejuvenation of immune function in the elderly.

A type of treatment for multiple sclerosis that 'resets' the immune system may stop progression of the disease in nearly half of patients. In a new study the treatment prevented symptoms of severe disease from worsening for five years, in 46 per cent of patients. However, as the treatment involves aggressive chemotherapy, the researchers stress the procedure carries significant risk. The treatment in the current study, called autologous hematopoietic stem cell transplantation (AHSCT), was given to patients with advanced forms of the disease that had failed to respond to other medications.

The one-off treatment aims to prevent the immune system from attacking the nerve cells. All immune system cells are made from stem cells in the bone marrow. In the treatment, a patient is given a drug that encourages stem cells to move from the bone marrow into the blood stream, and these cells are then removed from the body. The patient then receives high-dose chemotherapy that kills any remaining immune cells. The patient's stem cells are then transfused back into their body to re-grow their immune system. Previous studies have suggested this 'resets' the immune system, and stops it from attacking the nerve cells.

However, because the treatment involves aggressive chemotherapy that inactivates the immune system for a short period of time, some patients died from infections. Out of the 281 patients who received the treatment in the study, eight died in the 100 days following the treatment. Older patients, and those with the most severe forms of the disease, were found to have a higher risk of death. "In this study, which is the largest long-term follow-up study of this procedure, we've shown we can 'freeze' a patient's disease - and stop it from becoming worse, for up to five years. However, we must take into account that the treatment carries a small risk of death, and this is a disease that is not immediately life-threatening."

Link: http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_20-2-2017-17-40-27

Identification of a Potential Autophagy Enhancement Drug

Researchers here note the identification of a drug candidate to enhance autophagy, a process of cellular housekeeping responsible for removing damaged proteins and structures in the cell. Enhanced autophagy is associated with many of the interventions known to slow aging in laboratory species, and in at least some cases, such as for calorie restriction, the correct operation of autophagy has been shown to be necessary for extension of life span to take place. Consequently, the research community has for some time shown interest in the development of therapies based on the enhancement of autophagy, but there has been surprisingly little progress on this front to date.

Autophagy functions as a main route for the degradation of superfluous and damaged constituents of the cytoplasm. Defects in autophagy are implicated in the development of various age-dependent degenerative disorders such as cancer, neurodegeneration and tissue atrophy, and in accelerated aging. To promote basal levels of the process in pathological settings, we previously screened a small molecule library for novel autophagy-enhancing factors that inhibit the myotubularin-related phosphatase MTMR14/Jumpy, a negative regulator of autophagic membrane formation.

Here we identify AUTEN-99 (autophagy enhancer-99), which activates autophagy in cell cultures and animal models. AUTEN-99 appears to effectively penetrate through the blood-brain barrier, and impedes the progression of neurodegenerative symptoms in Drosophila models of Parkinson's and Huntington's diseases. Furthermore, the molecule increases the survival of isolated neurons under normal and oxidative stress-induced conditions. Thus, AUTEN-99 serves as a potent neuroprotective drug candidate for preventing and treating diverse neurodegenerative pathologies, and may promote healthy aging.

Link: https://dx.doi.org/10.1038/srep42014

The Media Meanders on the Topic of Enhanced Longevity

For various reasons, such as people promoting their books, the mainstream media has been giving more attention than usual these past few weeks to the topic of healthy life extension. The quality of the resulting articles is fairly low, as is usually the case. When given marching orders to cover any particular topic, the average journalist grabs the first few specific items that show up in a search of recent articles, wraps them with some pretty words, and launches the result without any attempt at achieving or conveying real understanding of the subject. When it comes aging and efforts to treat aging as a medical condition, just like any other quite complex topic in science and medicine, that real understanding is absolutely vital in order to distinguish between arrant nonsense, legitimate but poor approaches, and efforts that might do very well indeed if given sufficient support. The media is not the place to search for comprehension, on this or any other subject, sadly. So we see articles in which supplements, calorie restriction mimetic research, senescent cell clearance, and spa treatments are all ranked equally, without judgement or insight - options spanning the gamut of the aforementioned arrant nonsense through to potentially viable rejuvenation therapies.

Does it do the cause of human rejuvenation any good to have the press talk more rather than less, when nine-tenths of what is published is wrong, useless, or outright disinformation? It can be argued that there is no such thing as bad publicity. If these bland articles spur some people into moving from the class of those who do nothing into the class of those who head off to find out more, then some of the more active of those folk will eventually make their way into our community. There are many roads to learning about SENS-like rejuvenation research: from the personal health and fitness world; from time spent in other areas of the life sciences; from a passing interest in living longer acquired via supplement sellers; because it is talked about among members of an otherwise unrelated community, such as in the Bay Area technology circles; and so forth. So long as people arrive and help with meaningful progress in research and development, help to grow the community, I don't think the road taken matters all that much. Even if it starts with a few eye-rollingly terrible articles in the press.

Only Human: Meet the hackers trying to solve the problem of death

It is tempting to see transhumanism as merely the latest rebranding of a very old desire, for immortality. Aubrey de Grey is a biomedical gerontologist who sees death as a disease to be cured. Anders Sandberg, a neuroscientist working on mind uploading, wishes literally to become an "emotional machine." Zoltan Istvan ran a presidential campaign that saw him travel across the country in a coffin-shaped bus to raise awareness for transhumanism. He campaigned on a pro-technology platform that called for a universal basic income, and promoted a Transhumanist Bill of Rights that would assure, among other things, that "human beings, sentient artificial intelligences, cyborgs, and other advanced sapient life forms" be "entitled to universal rights of ending involuntary suffering."

Then there's Max More, a co-founder of Extropianism, who runs the Alcor Life Extension Foundation in Scottsdale, Arizona. Alcor is a cryopreservation facility that houses the bodies of those hoping to be reanimated as soon as the technology exists. The bodies, "are considered to be suspended, rather than deceased: detained in some liminal stasis between this world and whatever follows it, or does not." Alcor is the largest of the world's four cryopreservation facilities, and houses 149 "patients," nearly 70 percent of whom are male.

Those working on immortality are long-term thinkers and fall, broadly, into two camps: those who want to free the human from the body, and those who aim to keep the body in a healthy condition for as long as possible. Randal Koene, like Max More, is in the first group. Instead of cryonics, he is working toward "mind uploading," the construction of a mind that can exist independent of the body. His nonprofit organization, Carboncopies, aims for "the effective immortality of the digitally duplicated self. Maybe it wouldn't be that much of a shock to the system to be uploaded, because we already exist in this prosthetic relationship to the physical world anyway, where so many things are experienced as extensions of our bodies."

Aubrey de Grey is in the second, body preservationist group, whose efforts tend to be slightly more modest: Rather than solving death, they focus on extending life. His nonprofit, SENS Research Foundation, focuses on research in heart disease and Alzheimer's, and other common illnesses and diseases. (SENS, like many organizations the transhumanists are involved with, has received funding from Peter Thiel.) De Grey's most mainstream contribution is the popularization of the concept of "longevity escape velocity," which is explained as follows: "For every year that passes, the progress of longevity research is such that average human life expectancy increases by more than a year-a situation that would, in theory, lead to our effectively outrunning death." One might dismiss such transhumanist visions as too extreme: so many men, so much hubris. And yet, at a time of great cynicism about humanity - and the future we're all barreling toward - there is something irresistible about transhumanism. Call it magical thinking; call it radical optimism.

Why Do People Want to Live So Long, Anyway?

Dr. Ezekiel Emanuel is famous for a lot of reasons. He's an acclaimed bioethicist and oncologist and has two very well known brothers, but another thing people always seem to remember about him is that article he wrote in 2014: "Why I Hope to Die at 75." Emanuel's embrace of an early end - one that's only a few years shy of the U.S. life expectancy of 78.8 -is the exact opposite of how most people in America feel about dying. In a survey from the Pew Research Center, nearly 70% of American adults said they wanted to live to be up to 100 years old. But why?

"The quest to live forever, or to live for great expanses of time, has always been part of the human spirit," says Paul Root Wolpe, director of the Emory Center for Ethics. People now seem to have particular reason to be optimistic: in the past century, science and medicine have extended life expectancy, and longevity researchers (not to mention Silicon Valley types) are pushing for a life that lasts at least a couple decades more.

How Silicon Valley Is Trying to Hack Its Way Into a Longer Life

The titans of the tech industry are known for their confidence that they can solve any problem - even, as it turns out, the one that's defeated every other attempt so far. That's why the most far-out strategies to cheat death are being tested in America's playground for the young, deep-pocketed and brilliant: Silicon Valley. Larry Ellison, the co-founder of Oracle, has given more than $330 million to research about aging and age-related diseases. Alphabet CEO and co-founder Larry Page launched Calico, a research company that targets ways to improve the human lifespan. Peter Thiel, co-founder of PayPal, has also invested millions in the cause, including over $7 million to the Methuselah Foundation, a nonprofit focused on life-extension therapies.

Rather than wait years for treatments to be approved by federal officials, many of them are testing ways to modify human biology that fall somewhere on the spectrum between science and entrepreneurialism. It's called biohacking, and it's one of the biggest things happening in the Bay Area. "My goal is to live beyond 180 years," says Dave Asprey, CEO of the supplement company Bulletproof. "I am doing every single thing I can to make it happen for myself."

Should We Die?

"So, you don't want to die?" I asked Zoltan Istvan, then the Transhumanist candidate for president, as we sat in the lobby of the University of Baltimore one day last fall. "No," he said, assuredly. "Never." Istvan, an atheist who physically resembles the pure-hearted hero of a Soviet children's book, explained that his life is awesome. In the future, it will grow awesomer still, and he wants to be the one to decide when it ends. Defying aging was the point of his presidential campaign. He knew he'd lose, of course, but he wanted his candidacy to promote the cause of transhumanism - the idea that technology will allow humans to break free of their physical and mental limitations. His platform included, in part, declaring aging a disease.

But his central goal-pushing the human lifespan far beyond the record 122 years and possibly into eternity - is one shared by many futurists in Silicon Valley and beyond. Investor Peter Thiel, who sees death as "the great enemy" of man, is writing checks to researchers like Cynthia Kenyon, who doubled the life-spans of worms through gene-hacking. Oracle founder Larry Ellison has thrown hundreds of millions toward anti-aging research, according to Inc magazine, and Google founders Larry Page and Sergey Brin launched the Google subsidiary Calico specifically with the goal of "curing death."

But let's assume, for the sake of argument, that it can be. Let's say human lives will soon get radically longer - or even become unending. The billionaires will get their way, and death will become optional. If we really are on the doorstep of radical longevity, it's worth considering how it will change human society. With no deadline, will we still be motivated to finish things? Or will we while away our endless days, amusing ourselves to - well, the Process Formerly Known as Death - while we overpopulate the planet? Will Earth become a paradise of eternally youthful artists, or a hellish, depleted nursing home? The answers depend on, well, one's opinion about the meaning of life.

SkQ1 Slows Accelerated Aging in Mitochondrial Mutator Mice

Mice engineered to generate a high level of deletion mutations in mitochondrial DNA exhibit accelerated aging. As in most cases of accelerated aging, we can debate whether or not it is correct to call it accelerated aging. The important point is whether or not the type of cellular damage involved provides a significant contribution to the normal aging process, which in this case it does. The normal lower levels of mitochondrial DNA damage are implicated as a cause of aging and age-related disease. Then the question becomes whether or not it is acceptable to continue to call it aging given a vastly greater presence of just one of the types of age-related damage, or is it now some other form of pathology?

Putting this to one side, here researchers show that SkQ1, a mitochondrially targeted antioxidant shown to modestly slow aging in laboratory species, helps to ameliorate the harm done by high levels of mitochondrial deletion mutations. To my eyes, at least, it would have been unexpected to find another outcome, given what is known of the mechanisms involved here. This class of targeted antioxidant compounds come with a good deal of evidence backing their impact on mitochondrial metabolism; to the degree that deletions occur due to oxidative damage, and to the degree that they in turn cause greater levels of oxidative damage throughout the cell through disarrayed mitochondrial function, the presence of antioxidants in the mitochondria should reduce the harmful outcomes. This class of compound is currently being developed as a treatment for inflammatory eye conditions, as this is one of the areas in which the benefits are both reliable and large, and the regulatory path to market is comparatively smooth.

As a cause for the decreasing health status that accompanies aging, mitochondrial deterioration has been repeatedly suggested. Particularly, it has been discussed that an accumulation of errors in mitochondrial DNA (mtDNA) replication would lead to mitochondrial dysfunction, including increased production of reactive oxygen species (ROS) that may both further deteriorate the mitochondria and affect the function of the rest of the cell. However, the significance of ROS for the aging process has been doubted, particularly based on observations in the mtDNA mutator mice. These mice accumulate errors in their mtDNA and demonstrate subsequent alterations in their respiratory chain composition. They also demonstrate an early occurrence of characteristics normally associated with aging, and they die at a young age. However, there has been no convincing evidence that oxidative damage causes these problems.

Experimentally, an alternative avenue to examine the possible involvement of ROS in the development of aging characteristics would be to examine the ability of mitochondrially targeted antioxidants to ameliorate the health problems associated with experimentally induced aging. In this paper, we find that the mitochondrially targeted antioxidant 10-(6'-plastoquinonyl)decyltri-phenylphosphonium cation (SkQ1) substantially counteracts the acquisition of aging characteristics in the mtDNA mutator mice. We also find that parameters for oxidative damage not earlier examined (cardiolipin depletion and accumulation of hydroxynonenal protein adducts) are diminished by SkQ1 treatment. These data clearly indicate that ROS production and oxidative damage are substantial factors in the development of aging characteristics in the mtDNA mutator mice.

As the presently reluctance to associate mitochondrial dysfunction with aging through ROS and oxidative damage are largely based on the notion that these phenomena were apparently not involved in aging in mtDNA mutator mice, and as our present data indicate the opposite to be the case, our observations may also be of significance for discussions of the nature of aging and the possibility to ameliorate the aging process therapeutically.

Link: http://dx.doi.org/10.18632/aging.101174

A Diet of Old Tissues Modestly Shortens Life Span

In an interesting series of experiments, researchers found evidence for a diet of old tissues to modestly reduce life span in flies and mice. If speculating on specific mechanisms, we might look to the various forms of metabolic waste and damaged proteins that accumulate with age; some of that might find its way past the digestive process to be incorporated into tissues and thereby accelerate the aging process. This sort of dietary influence on aging is already a much-debated topic regarding advanced glycation end-products, for example. The results of the studies here offer reinforcement for the SENS approach of damage repair to create rejuvenation, but sadly that is not the conclusion reached by the researchers involved. They instead look ahead to a much harder task with the prospect of only marginal benefits, which is to say safely altering cellular metabolism in order to slow down damage accumulation. This is an inferior approach to periodic damage repair, requiring far more research to realize, and capable of producing only lesser gains in health and life span.

A study offers evidence bolstering one long-held theory: that aging is caused, at least in part, by molecular damage accumulating in the cells. This damage is generated by nearly every cellular process by the work of enzymes and proteins and the life-sustaining metabolic processes that occur at every level of complexity, from simple molecules and cell components to whole cells and entire organs. Over time we have many, many damage forms, byproducts of enzyme function, for example, or of protein-to-protein interactions, errors in DNA transcription or translation. As a function of age, they accumulate, and eventually, it's more than the body can cope with.

Researchers found that feeding a diet of "old" organisms to yeast, fruit flies, and mice shortened their lifespans by roughly 10 percent. Here's how it worked: for yeast, the researchers formulated one cell-culture medium composed of extracts from young yeast cells and another of extracts from old ones. They then grew new yeast cells on each medium and watched to see which set would live longer. "Our hypothesis was that as yeast ages, it accumulates certain damage forms, and we wanted to test that specific damage and find out if it is deleterious for yeast."­­­­ The team replicated the same basic procedure in fruit flies and mice: they collected 5,000 freshly dead flies that had lived an average of 45 days, and sacrificed 5,000 others that were three to five days old. Then they prepared two homogenized diets, one composed of young flies and the other using the old ones. They fed these diets to young female fruit flies. The mice were fed diets of skeletal muscle from young and old farmed red deer (three years old versus 25) that replaced the animal-product components (insects, carrion, worms, etc.) of a normal mouse diet. Using mouse tissue was not feasible because of the large quantities needed for the experiment; deer meat was a suitably close match.

The experiments raise new questions - in a field that's full of them - and some of the results were a little unexpected. The researchers had expected to see larger differences in the test organisms' relative lifespans. The effect was consistent, however, across all three species. In the study, the authors interpret the minor-but-consistent effect to mean that damage accumulation may be only one contributing factor in aging, and also that damage caused by internal molecular changes may have a stronger effect than damage introduced through the diet. It's also likely that the damage arises from many processes. "And they all work together in a deleterious way. So the question is, how do we slow down this process? How do we restructure cellular metabolism so that this damage accumulates at a slower rate?"

Link: http://harvardmagazine.com/2017/02/old-food-reduces-lifespan

Discussions of Stem Cell Rejuvenation

Earlier this week I noticed a couple of very readable open access papers in which the authors discuss the potential for rejuvenation of stem cells as a means to address some aspects of aging. Reversing age-related stem cell decline has long been a topic of considerable interest in the broader longevity science and advocacy communities, ever since the stem cell medicine industry started up in earnest. Indeed, back in the early days of SENS rejuvenation research advocacy, when stem cells were in the news every other week, it was frequently necessary to emphasize that stem cell repair and replacement was just one of a range of necessary approaches to the treatment of aging. Even if an individual's stem cells were somehow perpetually kept in pristine condition, the other forms of cell and tissue damage that lie at the root of aging would still result in degeneration and death. The degree of benefit achieved from fixing just one type of damage is an open question - we will most likely only find out some years after the relevant therapies become widely available, as is about to happen for senescent cell clearance.

Stem cells and their supporting structures are, of course, important in the aging process. Stem cells are responsible for generating replacement somatic cells needed to keep tissues functioning, but with advancing age the supply of new cells dwindles. This decline is one of the causes of frailty and organ failure. At present it looks likely that the changes in stem cell activity are as much a matter of altered cell signaling as of damage to the stem cells themselves. Temporarily restored signaling may be one of the means by which cell therapies produce benefits, by putting native cells back to work. Why does signaling change with aging, however? From an evolutionary perspective this reaction to rising levels of damage may exist because it serves to reduce cancer risk and thereby lengthen life, at the cost of a slower demise through organ failure, though programmed aging advocates would argue that stem cell decline is selected to promote aging as a fitness strategy. From a purely mechanical perspective, it is still up for debate as to the degree to which stem cell declines are secondary to the other forms of molecular damage and waste accumulation outlined in the SENS view of aging. It isn't unreasonable to think that comprehensive repair elsewhere would lead to some degree of renewed stem cell activity as the signaling environment becomes more youthful.

Rejuvenating stem cells to restore muscle regeneration in aging

Adult muscle stem cells, originally called satellite cells (SCs), are essential for muscle repair and regeneration throughout life. Besides a gradual loss of mass and function, muscle aging is characterized by a decline in the repair capacity, which blunts muscle recovery after injury in elderly individuals. A major effort has been dedicated in recent years to deciphering the causes of SC dysfunction in aging animals, with the ultimate goal of rejuvenating old SCs and improving muscle function in elderly people. The emerging evidence indicates that the functional and numerical loss of SCs is a progressive process occurring throughout the lifetime of the organism. The long-lived quiescent SC accumulates many lesions caused by loss of homeostasis, metabolic alterations, and the aging environment. Although this process is gradual, it is accelerated in advanced old age to the extent that SCs become practically non-functional owing to senescence or apoptosis. In this context, disputes about which factors, intrinsic or extrinsic, are more dominant in dictating the fate of old SCs seem misplaced, and it is likely that both make important contributions to SC functional decline with aging.

A degree of success has been obtained in restoring the regenerative capacity of old muscle with both parabiosis experiments (extrinsic effect) and transplantation of ex vivo-rejuvenated SCs into old animals (intrinsic effect). The simplest explanation for these effects is the heterogeneous nature of SCs. Even in old age, the SC population includes a small percentage of functional SCs, with only limited accumulated damage that can be reversed still by extrinsic signaling factors or by ex vivo pharmacological inhibition of stress pathways such as p38 MAPK or JAK/STAT3. It is thus likely that the success of biochemical or genetic strategies applied to old SCs in transplantation experiments results from the proliferative amplification of a subset of highly regenerative cells. Alternatively, the health and fitness of old SCs could be increased by refueling "clean up" activities such as autophagy (which declines with aging) to eliminate damage, thus improving SC regenerative capacity after muscle injury and in transplantation procedures. Future interventions that could also be considered for combating age-related muscle regenerative decline may utilize the restoration of SC-niche interactions via the delivery of bioengineered molecules.

The key finding that the SC pool enters a state of irreversible senescence at a geriatric age implies that any treatment to rejuvenate endogenous stem cells should be implemented before this point of no return. It is also important to consider the link between SC regenerative potential and quiescence. It is generally well accepted that the more quiescent a stem cell is, the more regenerative capacity it has. It has also become clear that somatic stem cell populations are heterogeneous, with cells showing differing levels of quiescence. Highly quiescent subpopulations probably change with aging to become less quiescent and therefore of reduced regenerative capacity. SC heterogeneity should therefore be further investigated, with the aim of deciphering the molecular basis of quiescence. Understanding the quiescent state will allow early intervention aimed at preserving the highly regenerative quiescent subpopulations throughout life.

Likewise, strategies directed towards the expansion of relevant subpopulations of resident progenitor cells in the SC niche may be envisioned for reversing the age-associated muscle regenerative loss. Another unresolved issue is the interaction among the various events contributing to the loss of SC regenerative potential with aging. Research needs to focus on determining which events are causative and which are consequential. For example, DNA damage may induce the loss of baseline autophagy flux in old SCs, or alternatively DNA damage may be the consequence of oxidative stress resulting from the loss of autophagy flux. Defining the hierarchy of events leading to SC deterioration will enable the targeting of upstream events in order to achieve more efficient rejuvenation of SCs. Last but not least, in a low-turnover tissue like muscle, much of the damage to the quiescent SC is the result of the gradual decline (aging) of the niche composition and the systemic system. Future efforts to rejuvenate the regenerative potential of SCs should thus adopt a holistic view of the SC and its supportive environment.

Preventing aging with stem cell rejuvenation: Feasible or infeasible?

Preventing pathological conditions caused by aging, including cancer, osteoporosis, sarcopenia, and cognitive disorders, is one of the most important issues for human health, especially in societies with large aging populations. Although aging, defined by functional decline of cells/organs or accumulation of cell/organ damage, is one of the most recognizable biological characteristics in all creatures, our understanding of mechanisms underlying the aging process remains incomplete. The primary cause of functional declines occurring along with aging is considered to be the exhaustion of stem cell functions in their corresponding tissues. Stem cell exhaustion is induced by several mechanisms, including accumulation of DNA damage and increased expression of cell cycle inhibitory factors, such as p16 and p21.

Meanwhile, aging at cellular, tissue, organ and organismic levels has been reversed by exposing tissues from old animals to a young environment. Recent studies have suggested that stem cell rejuvenation could reverse organismal aging phenotypes, and that this could be achieved by inhibiting fibroblast growth factor 2, mammalian target of rapamycin (mTOR) complex 1, guanosine triphosphatase and cell division control protein 42. Several additional experiments, such as cross-age transplantation and heterochronic parabiosis, have revealed that some factors in the young systemic milieu can rejuvenate declined thymus gland function, as well as neural and muscle stem cell functions, in samples derived from elderly donors. Furthermore, heterochronic parabiosis experiments have also shown strong inhibition of young tissue stem cells by the aged systemic milieu or old serum.

Although cumulative cellular "intrinsic changes", such as DNA damage, oxidative damage, increased expression of cell cycle inhibitors and mitochondria dysfunction, have been considered likely culprits for the tissue decline observed with aging, cellular rejuvenation induced by young systemic milieu would have been impossible if "intrinsic changes" were the only cause of cellular aging. Therefore, these so-called "causes of aging" should be more properly regarded as effects of aging (i.e., these processes are not causes, but rather consequences of aging), the result of cellular decisions often defined by responses to "extrinsic stimuli". Here some questions arise: If aging at the cellular level were reversed, would it lead to the rejuvenation of the animal at an organismic level? Would it result in prevention of aging and, eventually, life extension?

Examining Changes in Fat Tissue Metabolism with Aging and Calorie Restriction

Here researchers look at some of the changes wrought in the metabolism of fat tissue, both over the course of aging, and under conditions of calorie restriction. Calorie restriction is the practice of eating fewer calories while still obtaining optimal levels of micronutrients. It has been shown to extend life in near all species and lineages tested to date. In the short term in humans it considerably improves measures of health, and over the long term is expected to greatly reduce incidence of age-related disease.

Understanding exactly how calorie restriction produces these benefits is a challenge, since it changes near every aspect of metabolism. Wading through the complexity of cellular biology in search of definitive proof and root causes has proven to be a sizable undertaking. Just look at the much-hyped investigation of sirtuins over the past decade or so, for example, and that is just one tiny slice of the molecular biochemistry relevant to calorie restriction. My prediction is that attempts to understand the calorie restriction response and other common altered states of metabolism in mammals will still be ongoing well into the era of widespread availability of rejuvenation therapies based on the SENS vision, as implementing treatments that repair known forms of cell and tissue damage is a much simpler undertaking than trying to recreate or improve upon the changes created by calorie restriction.

It has been long established that aging is the greatest risk factor for a range of diseases. Caloric restriction (CR) is a dietary intervention that delays aging and extends the period of health in diverse species. One of the hallmarks of caloric restriction is the marked reduction in adiposity, a consequence that may be important in the mechanisms of CR given the endocrine function of adipose tissue. Adipokines and lipokines secreted from white adipose tissue impact peripheral tissue fuel utilization and the balance of energy generation from lipid or carbohydrate sources. However, it is unclear what effect aging has on adipose tissue metabolic integrity and how that relates to secretion of systemic regulatory factors. Prior studies of gene expression in adipose tissues from old rats and adult mice show that CR induces expression of genes involved in multiple aspects of metabolism. A further difference includes the increased circulating levels of the adipose tissue-derived peptide hormone adiponectin with long-term stringent (40%) CR.

In order to understand whether age-related changes in adiposity are associated with a change in adipose tissue function, we undertook a cross-sectional mouse study focusing on adipose tissue metabolism and circulating levels of adipose tissue-derived signaling molecules. To capture the trajectory of aging, the study involved adult, late-middle-aged, and advanced-aged C3B6F1 hybrid mice. Parallel groups of mice on modest (16%) CR taken at each age served to uncover aspects of adipose tissue aging that were responsive to delayed aging. We investigated the relationship between adiposity, adipocyte size, and adiponectin levels at three age groups of mice on control or CR diets. We determined whether differences with age and diet were associated with changes in factors downstream of adiponectin and factors that connect with adiponectin signaling including NAD metabolism. To investigate differences in adipose tissue lipid metabolism, we profiled serum lipids including free fatty acids that are derived from adipose tissue. The goal of these studies was to determine how age and CR impacted adipose tissue function beyond simple differences in adiposity and whether relationships between adipocyte size and secretory profiles were sustained with age or altered with CR.

Adiposity and the relationship between adiposity and circulating levels of the adipose-derived peptide hormone adiponectin were age-sensitive. CR impacted adiposity but only levels of the high molecular weight isoform of adiponectin responded to CR. Activators of metabolism including PGC-1a, SIRT1, and NAMPT were differentially expressed with CR in adipose tissues. Although age had a significant impact on NAD metabolism, the impact of CR was subtle and related to differences in reliance on oxidative metabolism. The impact of age on circulating lipids was limited to composition of circulating phospholipids. In contrast, the impact of CR was detected in all lipid classes regardless of age, suggesting a profound difference in lipid metabolism. These data demonstrate that aspects of adipose tissue metabolism are life phase specific and that CR is associated with a distinct metabolic state, suggesting that adipose tissue signaling presents a suitable target for interventions to delay aging.

Link: http://onlinelibrary.wiley.com/doi/10.1111/acel.12575/full

Continued Trials to Quantify the Benefits of a Fasting Mimicking Diet

Beyond the actual science, researcher Valter Longo's innovation in calorie restriction studies was to find a way to commercialize the undertaking of eating less, thereby pulling more money and attention into the field. With commercial backing comes the funding needed for larger, more rigorous trials and monitoring of outcomes. Moving beyond the earlier studies of human calorie restriction, such as CALERIE, researchers are now attempting to reliably quantify the degree to which one needs to eat less to achieve meaningful benefits: how little and how long. The suggestion resulting from the more recent studies is that intermittent periods of low calorie intake may capture a sizable portion of the benefits realized from fasting or full time calorie restriction. As always it is worth noting that there is nothing special about the product under discussion here; a fasting mimicking diet is easy enough to put together on your own given the calorie and nutrient targets.

A new study finds that providing the body with a temporary, specifically formulated fasting mimicking diet (FMD) called ProLon causes cellular changes normally generated by several days of consecutive water-only fasting and may increase health and lifespan by partially turning back the aging clock. After animal results showing that this FMD reduces incidence of cancer and inflammatory diseases and extends lifespan, researchers have now published the results of a 100-participant randomized Phase II clinical trial demonstrating that ProLon targets the aging process and reduces risk factors for age related diseases such as diabetes, cancer, and cardiovascular disease in humans. These effects are believed to be caused by an increase in stem cell number and regeneration.

Pre-clinical studies demonstrated that ProLon provides the body with the necessary macro and micronutrients while keeping it in a fasting mode and activates stem cell-based regeneration in multiple organs and systems. ProLon is perhaps the first success story in a new but rapidly developing nutri-technology field. The understanding of the molecular connections between specific food components and genes that regulate aging and regeneration allows food to be used to promote cellular changes that are safe but more coordinated than those caused by drugs.

Researchers tested the effects of three monthly ProLon cycles on metabolic markers and risk factors associated with aging and age-related diseases. Each ProLon cycle lasts five consecutive days and does not require alteration to lifestyle during the remaining days of the month. Findings in humans were consistent with mouse studies showing a spike in circulating stem cells and delay in biological aging by promoting regeneration in multiple systems. Body weight, BMI, total body fat, trunk fat, waist circumference, systolic and diastolic blood pressure, cholesterol, insulin-like growth factor 1 (IGF-1), and C-Reactive Protein (a marker of inflammation) were significantly reduced, particularly in participants at risk for diseases, while relative lean body mass (muscle and bone mass) was increased. Low levels of IGF-1 are associated with a lower risk of cancer and diabetes. No serious adverse effects were reported.

Link: https://www.eurekalert.org/pub_releases/2017-02/cci-fm020717.php

A Sample of Recent Work on New Means of Detecting and Targeting Senescent Cells

Senescent cells are receiving a great deal more attention from the research community these days, as illustrated by the two papers on methods of senescent cell identification I'll point out today. How things have changed; it wasn't only a few short years ago that scientists struggled to raising funding for animal studies of senescent cell removal, in an environment of little interest in this aspect of cellular biology. That was the state of the field despite the weight of evidence, gathered over decades, for increased cellular senescence in old tissues to be a root cause of aging and age-related disease. Now that studies have demonstrated that targeted clearance of senescent cells improves health and extends healthy life span in mice, and now that the methods of clearance are being used to produce stronger direct evidence for specific age-related disease and loss of function to involve senescent cells, it seems that every other gerontologist is either revising existing views of aging to incorporate cellular senescence or adding studies of cellular senescence to their portfolio.

Most cells fall into a senescent state when they reach the end of their replicative life span, at which point they either self-destruct or are removed by the immune system. Damage from random mutation or a toxic tissue environment can also result in senescence, and should in theory lead to cell death in the same way as for replicative senescence. Complicating the picture somewhat, short-term localized increases in senescent cell presence also appear to be involved in the wound healing process. There may also be numerous multiple distinct forms of senescence with somewhat different behaviors - this is one of many blank spots remaining on the map of cellular biochemistry, presently under active investigation. Regardless, at the end of the day the ideal situation is that all cells that become senescent should self-destruct or be destroyed fairly soon thereafter. Unfortunately that is not the case in practice, and a fraction of these cells linger on, their numbers growing over the years. These cells cause harm primarily through the signals they generate, producing a potent mix of molecules know as the senescence-associated secretory phenotype (SASP) that degrades nearby extracellular matrix structures necessary for tissue function, spurs increased inflammation, and alters the behavior of neighboring cells for the worse. By the time that 1% or more of cells in a tissue have become senescent the SASP and its downstream consequences become a serious threat to health and organ function.

All of this amounts to a very good reason to support research into identification and removal of senescent cells. Therapies capable of clearing senescent cells should produce a form of limited, narrowly focused rejuvenation, improving health at any point in old age. Those therapies will have to be accompanied by improved assays in order to determine exactly how well they remove senescent cells, as well as to definitively establish links between senescence and specific aspects of age-related degeneration. Below find linked a couple of interesting open access papers in which the authors explore potential new approaches to assessing levels of cellular senescence in tissues and tissue samples. The more of this sort of thing the better, to my eyes. Competition tends to result in better solutions at the end of the day.

Detecting senescence: a new method for an old pigment

Senescent cells have been recently shown to contribute causally to the aging process. Elimination of senescent cells by suicide gene-meditated ablation of p16Ink4a-expressing senescent cells in INK-ATTAC mice has led to improvements in healthspan and lifespan suggesting that senescent cells are drivers of aging. This has prompted the scientific community to identify new interventions to target senescence as a therapy against aging and age-related diseases. However, despite remarkable advances, the detection of senescent cells, particularly in tissues, is still a major challenge. There are several reasons, both of a biological and methodological nature, which have hindered the identification of specific markers able to determine whether a cell is senescent or not.

Firstly, while senescence is characterized by numerous changes in gene expression, very few of these differences are exclusive to senescent cells. Secondly, senescence is a kinetic, multifactorial process, with several phenotypic changes occurring at different time points following the initial cell cycle arrest. This could explain why aged tissues are highly heterogeneous, possibly containing cells at different stages of the senescent programme. Thirdly, senescent cells manifest the phenotype differently depending on the type of inducing stimuli or the cell type. Finally, recent data have highlighted that senescence may play different physiological roles in different contexts. For instance, an 'acute' type of senescence has been shown to play a beneficial role during processes such as development or tissue repair, while a 'chronic' type of senescence may contribute to aging and age-related disease. The recent realization that there may be different types of senescent cells in tissues has created an additional obstacle to the identification of a universal marker.

The detection of senescence-associated β-galactosidase (SA-β-Gal) activity at pH 6 is probably the most widely utilized method for identification of senescent cells. Nevertheless, there are major limitations to this method. Given the growing realization that senescence is a multifactorial process, a multimarker approach is being favoured by many researchers in the field. Examples of currently used markers are as follows: increased expression of cyclin kinase inhibitors p21 and p16 and absence of proliferation markers; telomere-associated DNA damage foci; senescence-associated heterochromatin foci; loss of lamin B1; senescence-associated distension of satellites (SADS); and expression of components of the SASP amongst several others. Nonetheless, there is also growing realization that many of these markers are not exclusive to all types of senescence and may only occur in specific cell types.

Lipofuscin is a nondegradable aggregate of oxidized lipids, covalently cross-linked proteins, oligosaccharides and transition metals which accumulate within lysosomes. Multiple studies indicate that lipofuscin accumulates in various tissues and species with age, particularly postmitotic tissues such as the brain and cardiac and skeletal muscle. However, lipofuscin has also been shown to accumulate during replicative senescence of human fibroblasts. Lipofuscin is autofluorescent and can be visualized using fluorescent microscopy; however, several other histochemical methods have been described based on lipid detection, such as staining using Sudan Black B (SBB) amongst others. Here, a structurally similar compound to SBB has been designed and coupled to biotin. Commercially available SBB contain numerous impurities which impact on staining quality and justified the need to synthesize a new analogue. The chemical coupling with biotin allows its detection using antibiotin antibodies and thereby increases its detection sensitivity. This method is versatile: it can be used in fresh, frozen cells and tissues, but also in fixed material. Furthermore, it can be identified in cells using both microscopy and flow cytometry.

While the authors have convincingly demonstrated that lipofuscin accumulation correlates with senescent markers in cell culture and that lipofuscin increases in tissues with age, future work should investigate more thoroughly whether and to what extent the lipofuscin signal overlaps with other established senescent markers. A separate question which arises from this work is whether lipofuscin accumulation is a mere consequence of the induction of the senescence programme or whether its accumulation contributes causally to the development of senescence.

Senescent cells expose and secrete an oxidized form of membrane-bound vimentin as revealed by a natural polyreactive antibody

Studying the phenomenon of cellular senescence has been hindered by the lack of senescence-specific markers. As such, detection of proteins informally associated with senescence accompanies the use of senescence-associated β-galactosidase as a collection of semiselective markers to monitor the presence of senescent cells. To identify novel biomarkers of senescence, we immunized BALB/c mice with senescent mouse lung fibroblasts and screened for antibodies that recognized senescence-associated cell-surface antigens by FACS analysis and a newly developed cell-based ELISA. The majority of antibodies that we isolated, cloned, and sequenced belonged to the IgM isotype of the innate immune system.

In-depth characterization of one of these monoclonal, polyreactive natural antibodies, the IgM clone 9H4, revealed its ability to recognize the intermediate filament vimentin. By using 9H4, we observed that senescent primary human fibroblasts express vimentin on their cell surface, and mass spectrometry analysis revealed a posttranslational modification on cysteine 328 (C328) by the oxidative adduct malondialdehyde (MDA). Moreover, elevated levels of secreted MDA-modified vimentin were detected in the plasma of aged senescence-accelerated mouse prone 8 mice, which are known to have deregulated reactive oxygen species metabolism and accelerated aging.

Based on these findings, we hypothesize that humoral innate immunity may recognize senescent cells by the presence of membrane-bound MDA-vimentin, presumably as part of a senescence eradication mechanism that may become impaired with age and result in senescent cell accumulation. Given the growing evidence that oxidized proteins are involved in the development of human disease, the detection and monitoring of secreted proteins like oxidized vimentin is certain to become a vital and noninvasive biomarker for monitoring age-related illnesses.

The Benefits of Hormesis Require Autophagy

Hormesis describes the outcome of a little damage inflicted upon an organism or tissue resulting in a net gain in health and function. Exercise, lack of nutrients, heat, and low levels of toxins or radiation all stress cells, damaging proteins and structures, causing the affected cells to boost their repair and maintenance efforts for some time. If the exposure to damaging circumstances is sufficiently mild and short-lived, then the overall result is an improvement, the additional maintenance activities more than compensating for the damage inflicted. Researchers here demonstrate that this beneficial response requires the cellular recycling process of autophagy, responsible for removing structures and proteins that have become damaged or dysfunctional. The research community has for some time shown an interest in building therapies to slow the progression of aging based on enhancement of autophagy, but beyond calorie restriction mimetic research there has been surprisingly little concrete progress on this front.

Biologists have known for decades that enduring a short period of mild stress makes simple organisms and human cells better able to survive additional stress later in life. Now, scientists have found that a cellular process called autophagy is critically involved in providing the benefits of temporary stress. Autophagy is a means of recycling cells' old, broken, or unneeded parts so that their components can be re-used to make new molecules or be burned for energy. The process had previously been linked to longevity. The new results suggest that long life and stress resistance are connected at the cellular level.

The researchers incubated C. elegans worms at 36 °C, significantly above the temperature they are usually kept at in the laboratory, for one hour. After this short heat exposure - a mild form of stress that improves the organism's survival - autophagy rates increased throughout the worms' tissues. When they exposed these heat-primed worms to another, longer heat shock a few days later, worms that were deficient in autophagy failed to benefit from the initial mild heat shock, as observed in heat-primed worms with intact autophagy.

The researchers reasoned that a mild heat stress might also improve the worms' ability to handle another condition that worsens with age - buildup of aggregated proteins, which is stressful for cells. To test this hypothesis, they used worms that model Huntington's disease, a fatal inherited disorder caused by neuronal proteins that start to stick together into big clumps as patients age, leading to degeneration throughout the brain. Exposing worms that make similar sticky proteins in different tissues to a mild heat shock reduced the number of protein aggregates, suggesting that a limited amount of heat stress can reduce toxic protein aggregation. "Our finding that brief heat exposure helps alleviate protein aggregation is exciting because it could lead to new approaches to slow the advance of neurodegenerative diseases such as Huntington's. This research raises many exciting questions. For example, how does induction of autophagy by a mild heat stress early on make cells better able to survive heat later - what's the cellular memory? There's a lot to follow up on."

Link: http://www.newswise.com/articles/what-doesn-t-kill-you-makes-you-stronger

Theorizing on a Mitochondrial Death Spiral

Mitochondria are the power plants of the cell, their activities essential for all energetic processes and actions in the body. They are descendants of symbiotic bacteria, a swarm in every cell, and carry their own DNA. Unfortunately that DNA can become damaged in ways that subvert the normal cellular quality control mechanisms to cause significant dysfunction; that a growing number of cells fall into this state over time is one of the contributing causes of aging and age-related disease. The author of this paper theorizes that mitochondrial DNA damage in aging is an example of antagonistic pleiotropy, meaning that it exists because evolution has guided mitochondrial structure and quality control processes to enhance early life success via mechanisms that also cause later failure and dysfunction.

From an evolutionary perspective, aging has been difficult to understand. Natural selection increases organismal fitness, and yet aging, which clearly decreases fitness, is not only observed, but also appears to be nearly universal within multicellular (and even some single-celled) organisms. To address this dilemma, it was proposed that aging occurs and is fixed in populations because alleles that have deleterious effects in old age benefit growth, survival, and reproduction in youth. This theory is called antagonistic pleiotropy (AP) theory. In this view, aging occurs because alleles that in the short term are beneficial in solving problems in growth and reproduction serve to exacerbate the problem in the long run. Therefore, aging can be viewed as a form of death spiral. A death spiral, also known as a vicious circle, is a specific form of positive feedback in which steps taken to handle a particular problem, while successful in the short term, exacerbate the problem in the long term.

If this premise is accepted, the next step is to identify the alleles that mediate AP, understand the nature of these alleles, how they might exert AP, and finally identify and define the critical cellular processes affected by AP. Although genes of the insulin signaling pathway likely participate in AP, the insulin-regulated cellular correlates of AP have not been identified. The mitochondrial quality control process called mitochondrial autophagy (mitophagy), which is inhibited by insulin signaling, might represent a cellular correlate of AP. In this view, rapidly growing cells are limited by ATP production; these cells thus actively inhibit mitophagy to maximize mitochondrial ATP production and compete successfully for scarce nutrients. This process maximizes early growth and reproduction, but by permitting the persistence of damaged mitochondria with mitochondrial DNA mutations, becomes detrimental in the longer term.

I suggest that as mitochondrial ATP output drops, cells respond by further inhibiting mitophagy, leading to a further decrease in ATP output in a classic death spiral. I suggest that this increasing ATP deficit is communicated by progressive increases in mitochondrial reactive oxygen species (ROS) generation, which signals inhibition of mitophagy via ROS-dependent activation of insulin signaling. This hypothesis clarifies a role for ROS in aging, explains why insulin signaling inhibits autophagy, and why cells become progressively more oxidized during aging with increased levels of insulin signaling and decreased levels of autophagy. I suggest that the mitochondrial death spiral is not an error in cell physiology but rather a rational approach to the problem of enabling successful growth and reproduction in a competitive world of scarce nutrients.

Link: http://onlinelibrary.wiley.com/doi/10.1111/acel.12579/full

Ichor Therapeutics Announces Lysoclear SENS Rejuvenation Therapy and Series A Fundraising for Further Development

As regular readers will be aware, the company Ichor Therapeutics has for the past year or so been actively developing one of the results of the LysoSENS medical bioremediation program in order to produce a viable therapy. Today there is news of progress, and the work is moving on to the next stage of development and funding. This line of research sought to find bacterial enzymes that can degrade forms of metabolic waste that our cellular biochemistry struggles with, particular the constituents of lipofuscin. Lipofuscin compounds, varying in type from tissue to tissue, accumulate in the cellular recycling system known as the lysosome. That is where cellular waste ends up, but what happens when it cannot be effectively broken down? The answer is that lysosomal activity starts to fail, and cells fall into a form of garbage catastrophe as a result, a process of growing damage and functional decline that, as it happens across all cells in a tissue, contributes to degenerative aging. In most cases the process of cause and effect that leads from lipofusin to age-related disease isn't clearly and completely mapped, but for some conditions the contribution of lipofuscin compounds is quite direct, and so better known. Ichor is focused on the metabolic waste compound A2E as it pertains to macular degeneration, a common age-related condition of progressive blindness. Here, researchers have very good evidence for the harms caused fairly directly via A2E accumulation.

The best thing to do with unwanted metabolic waste is to find a way to safely break it down so that its components can be recycled appropriately. Given that this waste is a cause of aging, successful removal will be a narrow, targeted form of rejuvenation. The path chosen by the SENS Research Foundation in their LysoSENS program was based on the observation that graveyards and similar locations do not appear to be saturated with human metabolic waste. Therefore soil bacteria must be consuming this material. Given the enormous number and variety of bacterial species, somewhere in there is very likely to be found one or more molecules that can form the basis for a drug that can break down metabolic waste compounds without harming cells. Finding such a compound starts with culturing bacteria in order to find those that can thrive on a diet of human lipofuscin, and after some years of work, a range of candidates for various forms of metabolic waste were indeed discovered, including one for A2E. Given a single suitable molecule, it is then possible to build others in the same class, and search for those that are most effective and least likely to harm cells and tissues via unwanted side-effects.

The lipofuscin constituent A2E is peculiar to the very energetic metabolism of retinal cells, so Ichor Therapeutic's work is the production of a very narrowly focused rejuvenation therapy indeed, applicable only to this tissue in the eye. It is nonetheless a rejuvenation therapy and one of a growing number of examples of the work of the SENS Research Foundation moving to the clinic. This may be just one tissue, but there are a great many patients suffering with macular degeneration, no currently effective treatment for the dry form of the condition, and consequently signs of progress in the field tend to attract attention from Big Pharma. The work of the SENS Research Foundation and Ichor Therapeutics here is another article of proof to show that the right way to proceed towards the effective treatment of aging and age-related disease is to repair and reverse the fundamental differences between old and young tissue - such as the accumulation of metabolic waste that our biochemistry cannot effectively break down.

Considering all of this, I'm pleased to note, both as an investor in the company and as someone who wants to see the field of rejuvenation research grow enormously, that the work at Ichor Therapeutics has continued to produce excellent results as it moved into animal studies. The company has accordingly announced the Lysoclear product line, and is now seeking series A funding for further development leading towards a clinical therapy to turn back the progression of macular degeneration by removing one of the root causes of the condition, the A2E accumulation. Everyone who, back in the day, helped out with the early LysoSENS research in one way or another, as researchers, advocates, and donors to the Methuselah Foundation and SENS Research Foundation, should be feeling proud and vindicated today.

Lysoclear

Lysoclear is an enzyme therapy being developed for age-related macular degeneration (AMD) and Stargardt's macular degeneration. Age-related macular degeneration (AMD) is the leading cause of vision loss among people over the age of 50, affecting 20 million Americans. Stargardt's macular degeneration is an inherited conditions that robs children of their sight. Lysoclear shows promise as a highly targeted treatment for both conditions. Lysoclear has been extensively studied in buffer systems, cell culture models, and in vivo, and findings suggest that Lysoclear is safe and effecting at destroying toxic vitamin A aggregates (A2E) that may cause these diseases. Lysoclear is safe and effective at breaking down toxic A2E, removing up to 10% with each dose. Lysoclear selectively localizes to the lysosomes of retinal pigmented epithelial (RPE) cells where A2E accumulates, and destroys it.

Age-related macular degeneration (AMD) and Stargardt's macular degeneration (SMD) are thought to arise from the gradual loss of RPE cells of the macula, the area of the eye responsible for central vision. The accumulation of toxic vitamin A aggregates, including the bis-retinoid A2E, have been implicated in these diseases. Recent research suggests that A2E is capable of binding native lysosomal enzymes, inhibiting their function. As A2E accumulation reaches a critical threshold, lysosomal impairment leads to the accumulation of intracellular lipofuscin, extracellular drusen deposition, and eventually RPE cell death. Lysoclear is a recombinant enzyme product under development by Ichor Therapeutics that is able to selectively localize to the lysosomes of RPE cells where A2E accumulates, and destroy it.

Ichor Therapeutics announces series A offering for LYSOCLEAR to move first SENS therapy into the clinic

Today, Ichor Therapeutics, a biotechnology company that focuses on developing drugs for age-related diseases, announced a series A offering to bring its Lysoclear product for age-related macular degeneration (AMD) and Stargardt's macular degeneration (SMD) through Phase I clinical trials. This product would be the first clinical candidate based on the SENS paradigm, pioneered by biomedical gerontologist Dr. Aubrey de Grey. AMD is the leading cause of vision loss among people over the age of 50. The underlying pathology of AMD is thought to be caused by the death of retinal pigmented epithelial (RPE) cells, which photoreceptors in the macula rely upon to survive. RPE cells assist photoreceptors in various metabolic roles, including the recycling of vitamin A, an essential component of the visual cycle. However, this is a leaky process, and trace by-products are formed that accumulate in the lysosomes of RPE cells. The most well studied of these by-products is A2E, a toxic compound which may play a causative role in AMD and SMD.

Although A2E accumulates gradually over the lifespan, it is generally not until later age that A2E reaches a threshold necessary to promote toxicity. At high concentrations, A2E promotes the formation of intracellular junk termed lipofuscin. RPE cells attempt to handle this accumulation by shuttling the junk out in the form of extracellular drusen. Eventually, the RPE cells choke on the garbage, and cell death accompanies complement activation, inflammation, and hypoxia. Multiple companies have developed drugs that successfully reduce the rate of A2E formation, but such interventions may be too late for symptomatic patients, who have already had the cascade kicked off.

In 2014, Ichor Therapeutics completed a material and technology transfer agreement for rights to concepts and research pioneered by SENS Research Foundation. In 2017 Ichor announced Lysoclear, a recombinant enzyme product that selectively localizes to the lysosomes of RPE cells where A2E accumulates, and destroys it. Ongoing studies suggest that LYSOCLEAR is safe and effective at targeting A2E, eliminating up to 10% with each dose. Ichor has opened a Series A funding round to support pre-clinical Investigational New Drug (IND) enabling studies and phase I human clinical trials for AMD and SMD.

A Different Take on a Cellular Garbage Catastrophe in Neurodegeneration

The garbage catastrophe view of aging in long-lived cell populations with little turnover, such as those of the brain, is fairly well established. Over-simplifying somewhat, it is a downward spiral in which accumulated molecular damage and metabolic waste in cells makes their maintenance processes ever less efficient, which in turn leads to a faster increase in damage and waste. That ultimately leads to cellular senescence, or programmed cell death, or other forms of dysfunction. Here, researchers present a somewhat different take on a garbage catastrophe, one in which cells sabotage one another by ejecting waste and damaged proteins into the surrounding environment:

Neurodegenerative diseases like Alzheimer's and Parkinson's may be linked to defective brain cells disposing toxic proteins that make neighboring cells sick. Researchers found that while healthy neurons should be able to sort out and rid brain cells of toxic proteins and damaged cell structures without causing problems, this does not always occur. These findings could have major implications for neurological disease in humans and could possibly be the way that disease can spread in the brain. "Normally the process of throwing out this trash would be a good thing. We think that there might be a mismanagement of this very important process that is supposed to protect neurons but, instead, is doing harm to neighbor cells."

Scientists have understood how the process of eliminating toxic cellular substances works internally within the cell, comparing it to a garbage disposal getting rid of waste, but they did not know how cells released the garbage externally. "What we found out could be compared to a person collecting trash and putting it outside for garbage day. They actively select and sort the trash from the good stuff, but if it's not picked up, the garbage can cause real problems."

Working with the transparent roundworm C. elegans, which are similar in molecular form, function, and genetics to those of humans, researchers discovered that the worms - which have a lifespan of about three weeks - had an external garbage removal mechanism and were disposing these toxic proteins outside the cell as well. The team realized what was occurring when they observed a small cloud-like, bright blob forming outside of the cell in some of the worms. Over two years, they counted and monitored their production and degradation in single still images until finally they caught one in mid-formation. Roundworms engineered to produce human disease proteins associated with Huntington's disease and Alzheimer's threw out more trash consisting of these neurodegenerative toxic materials. While neighboring cells degraded some of the material, more distant cells scavenged other portions of the diseased proteins.

Link: http://news.rutgers.edu/research-news/alzheimer%E2%80%99s-may-be-linked-defective-brain-cells-spreading-disease/20170212

Calorie Restriction and the Ribosome

Ribosomes are structures within which protein assembly takes place in cells. Many interventions that modestly slow aging, such as calorie restriction, are associated with both a slower rate of protein production and a slower turnover of ribosomes - which, like near all structures in the cell, are periodically replaced as they become damaged or dysfunctional. The direction of causation in this and associated effects is still up for debate, though a consensus is emerging. In this context it is interesting to note that there is some evidence for selective ribosomal dsyfunction to mimic some of the effects of calorie restriction. Further, naked mole-rats, those paragons of mammalian longevity, have been found to have highly efficient ribosomes. Determining how this all fits together into a coherent picture of the effects of calorie restriction on aging, as well as the differences in aging between short-lived versus long-lived species, is still a work in progress.

Recent research offers one glimpse into how cutting calories impacts aging inside a cell. The researchers found that when ribosomes - the cell's protein makers - slow down, the aging process slows too. The decreased speed lowers production but gives ribosomes extra time to repair themselves. "The ribosome is a very complex machine, sort of like your car, and it periodically needs maintenance to replace the parts that wear out the fastest. When tires wear out, you don't throw the whole car away and buy new ones. It's cheaper to replace the tires." So what causes ribosome production to slow down in the first place? At least for mice: reduced calorie consumption.

Researchers observed two groups of mice. One group had unlimited access to food while the other was restricted to consume 35 percent fewer calories, though still receiving all the necessary nutrients for survival. "When you restrict calorie consumption, there's almost a linear increase in lifespan. We inferred that the restriction caused real biochemical changes that slowed down the rate of aging." The team isn't the first to make the connection between cut calories and lifespan, but they were the first to show that general protein synthesis slows down and to recognize the ribosome's role in facilitating those youth-extending biochemical changes. "The calorie-restricted mice are more energetic and suffered fewer diseases. And it's not just that they're living longer, but because they're better at maintaining their bodies, they're younger for longer as well."

Ribosomes, like cars, are expensive and important - they use 10-20 percent of the cell's total energy to build all the proteins necessary for the cell to operate. Because of this, it's impractical to destroy an entire ribosome when it starts to malfunction. But repairing individual parts of the ribosome on a regular basis enables ribosomes to continue producing high-quality proteins for longer than they would otherwise. This top-quality production in turn keeps cells and the entire body functioning well.

Link: http://news.byu.edu/news/how-eating-less-can-slow-aging-process

Methuselah Foundation Reports on the Achievements of 2016

Methuselah Foundation, co-founded by David Gobel and Aubrey de Grey, was the first organization to begin earnest funding of SENS rejuvenation research, and those efforts ultimately led to the creation of the SENS Research Foundation some years ago, and the considerable progress towards rejuvenation therapies accomplished since then. Methuselah Foundation has long undertaken a range of other work as well, and that continues today. The organization has acted as an incubator of sorts over the years, using the philanthropic donations of members of the Methuselah 300 to help seed fund a number of companies involved in regenerative medicine and the production of rejuvenation therapies, such as Organovo and Oisin Biotechnologies. Additionally, Methuselah Foundation has funded an eclectic range of aging research programs, and continues to work on research prizes and similar efforts, many under the New Organ banner, to draw more funding into aging research, tissue engineering, and other related fields.

Earlier today Methuselah Foundation sent out a retrospective to supporters and donors, looking back at the progress achieved in various initiatives over the course of 2016. It certainly seems like things are moving more rapidly of late, and 2017 is shaping up to provide more of the same. Of particular note here is the progress achieved by the more recent batch of companies funded by Methuselah Foundation, and the news that Methuselah Foundation will be formalizing its notably successful incubator-like activities with the creation of an investment fund. This is far from the only new longevity-focused fund emerging at this time, and we can hope that as a result there will be considerably more capital available for companies working on rejuvenation therapies in the near future.

We thought this would be a good time to not only thank you for the support you have given the Methuselah Foundation, but also to review the progress we made through your support over the past year. Much of what you'll read in this year in review letter is very late-breaking, and leads us to believe that 2017 will be a very important year in medical developments. 2016 took us a broad step closer to fulfilling our mission statement to "Make 90 the New 50, by 2030". Why can we say that? For starters, let's look at several achievements to date that made this year so successful:

Our Partnership with NASA

The White House Organ Summit was held this past June. At the formal press event we announced that we NASA had chosen to partner with us as leaders in the industry, along with the New Organ Alliance and CASIS to organize and administer a $500,000 prize to the first three teams who successfully create vascularized thick human tissue; the intended outcome is that it can be developed for therapeutic applications here both on earth (such as closing the gap in the organ shortage) and in deep space exploration. Why is this important? The outcome we are reaching for with the Vascular Tissue Challenge is in lockstep with our goal to bring "new parts for people" to the clinic - not just full organs for transplant, but all tissues: new skin, cartilage, nerve, vessels and bone. Microvascularization is the key barrier to allowing the explosion of progress towards "new parts for people". Methuselah is leading the way to pierce and destroy this barrier.

We have several updates on the NASA Vascular Tissue Challenge for you. Seven teams have now signed up to officially pursue the Vascular Tissue Challenge, and we co-chaired a session on the New Organ road-mapping work and Vascular tissue Challenge at the World Stem Cell Summit Dec 5-10. To aid in this endeavor, we completed a second road-mapping workshop with specific focus on overcoming the thick-tissue vascularization barrier. This was hosted at NASA Ames, Nov 9-10. We received participation from 100 leaders in the field, along with government representatives from NIH, NSF, VA, NASA, and DOD. We are pursuing the development of an expanded road-mapping Summit for 2017 that will be supported by NASA, NIH, NSF, CIRM, and other partners. We have made plans to expand the New Organ Alliance into an official Research Coordination Network with the NSF next year. This partnership with NASA and other medical pioneer organizations could lead to alleviating the suffering of those in need of organs, and add to the quality of life for millions in the future. It has us very excited!

Organovo

In September of this year our partner and portfolio company Organovo announced it had created the world's first ever 3-D architecturally correct human kidney tissue assays. What makes this a game changer? This development alone may cut off a decade or more of time, and save billions of dollars wasted in drug development. The ability to test viable human tissue will also make animal testing obsolete. The end result can also make much more effective drugs available much more quickly, and at a much lower cost. In addition, Organovo is continuing to build on these achievements by moving forward with work on a 3-D liver tissue "patch" for therapeutic use. These patches will help heal diseased kidneys and are on track to be developed in three to five years. We were also excited to announce, as part of our ongoing 3d Tissue Engineering University Printer Grant program, the UCSF bone organoid 3d Printer partnership in June 2016. This partnership is designed to research creation of new bones and cartilage. The Methuselah Foundation has also awarded a 3-D printer grant to Dr. Melissa Little of the Royal Children's Hospital in Melbourne, Australia, allowing her to collaborate with Organovo in this endeavor.

Organ Preservation Alliance

During 2016 the Organ Preservation Alliance was responsible for the launch of new cryopreservation and organ preservation initiatives, which were announced by the White House. Among them was a partnership with the American Society of Transplantation to launch a new branch of its organization devoted to advancing organ preservation and cryobanking. This resulted from an Organ Preservation Alliance-hosted roundtable on Capitol Hill that brought together almost 50 leaders from the American Heart Association, American Liver Foundation and other large stakeholder organizations. Also announced by the White House in 2016 was the upcoming Organ Banking Summit at Harvard, which brings together leading cryopreservation researchers and top researchers from other fields, prestigious journals, and transplant leaders. Other initiatives announced included $15 million in grants launched by the Dept. of Defense resulting from the Organ Preservation Alliance, a Breakthrough Ideas in Organ Banking hackathon, and a technology road-mapping program in partnership with New Organ, the American Society of Mechanical Engineers, and other organizations.

Leucadia

Our work through Leucadia Therapeutics has also yielded eye-opening developments this year. We continue to study the brain with a view towards alleviating the suffering of people and their loved ones when Alzheimer's disease begins to take its toll. We have undertaken deep examination of the cribriform plate, along with some otherwise overlooked approaches to studies of the brain and surrounding tissue and material. We believe we have originated approaches to treatment that appear to be profound. We are currently evaluating cribriform plates in Alzheimer's patients at a level of detail that has never been done before. This new level of detail that was only reached in late 2016 has opened doors to treatment that was unthinkable only a year ago. While we cannot elaborate at length on what or why we consider this approach "profound", we do want you to know we have a clear and definite path we are following. Our research is heading in a direction that could very well bring previously unmatched value to those suffering from Alzheimer's.

Oisin

Oisin Biotechnology made strong progress in recent months as we pursue a multi-pronged research in areas of longevity science. As a result of grants from Methuselah Foundation, Oisin has continued to pursue senescent cell ablation, and continues laying groundwork in eliminating senescent cells based on their gene expression. Research strongly implicates those cells in the aging phenotype, and removal has been shown to extend median survival and health span in mice. Oisin and our colleagues have greatly improved both the manufacturability and efficiency of our liposomal manufacturing process, which was a large, necessary step towards making the future therapy cost effective and affordable. We've also confirmed our findings of last year that our patent-pending approach effectively kills senescent cells in cell culture.

With support from Methuselah, SENS Research Foundation, and their longtime supporters, Oisin was able to secure sufficient funds for their continuing operations and thus avoid the need for venture capital - allowing it to focus on achieving Methuselah's strategy to "get the crud out". Oisin is also actively pursuing research in another very significant field that cannot be revealed in detail at this time of crucial testing and verification. However, our research on this particular project has exceeded all expectations. Once our verification work concludes, we will reveal this exciting work to all those of you who power the Methuselah Foundation. We are driven to get this to the clinic. What we are doing is not simply an academic pursuit! We are working hard to make a lasting and valuable difference in people's lives.

The Establishment of the Methuselah Fund

On December 2016, the Methuselah Foundation started a new initiative it expects will accelerate clinical delivery of mission relevant interventions. It is called the Methuselah Fund, or M Fund. Currently, the foundation believes that one of the fastest and most effective ways to achieve our mission is by investing in for-profit companies. We want to replicate and expand our successes via the M Fund, and we would love for you, our network, to be a part of this initiative.

Our Thanks to You

The Methuselah Foundation takes great pride and joy to inform you of all of these strides we are making in so many places. Through 2017 we will continue to think of the number of lives that may be saved. The amount of pain alleviated or even completely removed from families. It drives our researchers and associates to get up every day and push forward. Most importantly though, we never lose sight of the fact that it is you that makes our work possible. You continue to create the momentum for earth-changing progress. We want to thank all of you for your contributions to our Foundation that in turn empowers us to utilize the tools that will make a difference in so many people's lives, everywhere. We look forward to another rewarding year ahead with you, as we continue to push forward, creating a future that helps end suffering and changes the lives of millions.

The Bold Choice to Help Longevity Science by Becoming a Researcher

There are a number of people presently working in the field of aging research who were originally involved in entirely different careers, completely unrelated to the sciences. Then they learned of the potential opportunities to treat aging as a medical condition and extend healthy life - that, given sufficient support, the research and development community could produce working rejuvenation therapies in the years ahead. Unlike the rest of us, engaged in advocacy and philanthropy as our time and income allow, these people took the brave, bold leap to leave their old careers behind and start over as scientists and biotechnologists, going back to school, and then taking on jobs in the field. I have the greatest of admiration for the individuals who have achieved this goal; they are an inspiration to us all.

I am a first year Biostatistics PhD student at the University of Colorado. Listening to J. D. Vance's Hillbilly Elegy reminds me of my roots growing up along US 23 in Eastern Kentucky. So who am I? I'm the guy who fixed your air conditioner, roofed your house, changed the spark plugs in your car's engine, worked the production line in a food factory, defended your country during war, waited your table at your favorite restaurant and even washed your dishes after you were done. Now, I want to join the united front to end the most widespread cause of human suffering - aging. It was a very serendipitous moment that inspired me to read Aubrey de Grey's book Ending Aging in 2008. I was living in Louisville, Kentucky and spent my free time from working at a White Castle frozen hamburger factory hanging out in a local coffee shop. Adjacent to that coffee shop was Carmichael's, a local, independent bookstore. That day I went straight to my favorite section, Science and Math. And what I found was not just a book, but hope.

Ending Aging spoke to me. Dr. de Grey told us not to accept humanity as the limits of our DNA. Challenge the status quo and possibly discover how great we may become. Every generation believes that they can do better than their parent's generation. Until one day that generation wanes into the symptoms of aging. Great men and women lose their dignity because a care worker or family member has to perform what once were remedial tasks for them. But the indecencies attached to the aged bodies of our loved ones wasn't what sold me on SENS. Dr. de Grey's analogy of maintaining an antique car caught my attention early in the reading of his book. This was a direct appeal to my inner mechanic. I read during my 30-minute lunch breaks at the White Castle hamburger factory. Separating six burgers into three sets of two on a transfer belt and sliding them into a moving slot to be wrapped in cellophane at a rate of one pair per second, I would let my mind wander into another world. What are the seven categories of damage that would need to be reversed? Is this list all encompassing? Doing repairs may be easier than changing metabolic pathways, but would it even be possible. What would a society be like if age-related illnesses were eliminated? I was onboard and wanted to be a part of the next step in human improvement.

There was this moment where I decided to stop spoon feeding my wife the ideas of SENS and unleashed all my thoughts on her at once. When I proposed the idea of me becoming a researcher, it became apparent that working 60+ hours a week at a factory and having two kids under the age of three would not be an ideal time to go back to school. Hence, we waited. I obtained a horizontal promotion as a service technician for the restaurant division. I still read cellular biology books in my spare time and googled Aubrey de Grey more than once a week to see his progress. Then, an opportunity presented itself to me. My neighbor found it interesting that this mechanic neighbor of his was reading biology textbooks when he wasn't being called out in the middle of the night to fix a freezer. He asked me if I would be interested in a career in the medical field and said he could get me an interview but that was it. I had to submit a resume before my interview. There was nothing in my past that would qualify me for this job. Nonetheless, my new boss hired me and said they could teach me what I didn't know.

Later, with great support from family and friends, I finished two degrees, BS Pure Mathematics and MS Biostatistics. Currently, I am focusing on my studies as a first year PhD student in Biostatistics in the beautiful state of Colorado. The teaching staff here is incredible. They are pushing me to be the best I can be while still providing me some space to allow my family and myself to adapt to our new environment. I am taking a course on genomics which has a strong emphasis on the technology of measuring gene expression and various sequencing platforms. I just published my first paper in Breast Cancer Treatment and Research as a primary author. After my doctorate, I would like to work on a research team in a biotech company. I am open to academic research and wouldn't discount any opportunity. My desire is to spend my days working with innovative people to solve the mysteries of controlling aging. I don't care what platform provides that for me.

Link: http://www.leafscience.org/mechanic-to-scientist/

Introducing Geroscience

Geroscience is a new popular science of aging online magazine supported by the Apollo Ventures investment fund, devoted to longevity science startups. The principals there became involved in this space and raised a fund both because they are enthused by the field of therapeutics to treat aging and want to see it succeed, but also because they recognize the tremendous potential for profit here. The size of the market for enhancement biotechnologies such as rejuvenation treatments is half the human race, every adult individual. Publishing a magazine on aging research is a way to help broaden their reach within the community, find more prospective investments, talk up their positions, and raise the profile of the field as a whole, all of which aligns fairly well with the broader goals of advocacy for longevity science. Many hands make light work, and we could certainly use more help to speed up the growth of this field of research and development.

Modern health and medicine have all but eradicated the poxes and plagues that fixed the life expectancy of a person in the 19th century at 40 years old, but despite long and expensive struggles like "The War on Cancer" and over a hundred clinical trials for Alzheimer's treatments, our attempts to control the diseases of aging have borne little fruit. In the last thirty years, our understanding of the underlying pathology of Alzheimer's disease has deepened, yet billions of dollars invested in research have not significantly slowed the course of the disease. Most existing treatments for cancer require swift detection, are extremely invasive and expensive, and cause debilitating side effects. And our defenses against heart disease, stroke, and general frailty remain, at best, crude.

Up to now, most approaches have focused on acute treatment of disease, waiting until a patient has obvious or life-threatening symptoms before intervening. The central tenet of geroscience, however, is that the molecular and cellular damage that leads to the diseases of aging begins long before people appear sick. Our risk of getting these diseases peaks after sixty years of age, but the incremental buildup of damage starts in our twenties or thirties. The geroscience approach aims to target the molecular processes that underpin aging here, and fix them at their roots, stopping aging before it starts.

But what are these processes? What are the threads linking all of the ails of aging together to slowly break down our bodies and minds? Over several decades, researchers have unraveled this mystery to find nine interwoven "hallmarks of aging": genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. Already interventions targeting one or more of these factors are being developed, from small molecule drugs to genetic alterations, and over fifty have been found to extend lifespan and healthspan in mice, with more being discovered every year.

In the past few years, a rapidly growing industry has sprung up around the geroscience approach, with both companies producing individual technologies like UNITY Biotechnology, and tech giants like Google and Facebook making broader moves into the space. Google's Calico, an independent R&D biotech company partnering with AbbVie and numerous academic institutes, was founded in 2013 to promote "health, well-being, and longevity", and in 2016 Mark Zuckerberg pledged $3 billion to Chan Zuckerberg Science with the goal of curing or preventing all disease by 2100. In addition to these large investments into basic research, more commercially focused endeavors like Genentech and Eli Lilly's Alzheimer's trials and GenSight's efforts to replace defective mitochondrial genes have been popping up as well. We are on the verge of a paradigm shift in how we treat the diseases of aging. The first medicines to make us live longer and healthier lives already exist, and massive investments are catalyzing the creation of many more. We are poised to be either the first generation to live for over a century, or the last generation not to. We've created Geroscience to share our enthusiasm for this space, and to cultivate a source of accessible science and realistic discourse.

Link: http://geroscience.com/editorial-geroscience/

The Lifespan.io CellAge Fundraiser for Better Senescent Cell Assays is Nearly at the Target: Help us to Reach the Goal

An increasing number of senescent cells in our tissues is one of the contributing root causes of aging and age-related disease. A new industry is springing up to find ways to selectively destroy these cells. CellAge is one of the more recent efforts focused on this rapidly growing field of cellular senescence. The principals aim to build better tests to assess the presence and impact of senescent cells in old tissues, based on gene promotor biotechnology. The present assays for senescent cells are showing their age; some are going on twenty years old, and they're all fairly clunky and laborious. Clunky and laborious has been good enough for the limited amount of research work on cellular senescence that took place up until fairly recently, but is in no way a sufficient foundation for the sort of low-cost, low-effort clinical diagnostics required by the forthcoming industry of senescent cell clearance therapies. It is one thing to undergo a senescent cell therapy, and quite another to reliably and quickly understand exactly how well it performed; both removal of cells and assessment of that removal are needed for optimal progress towards widespread clinical availability.

CellAge intends to make the assays resulting from their initial development program freely available to academic groups, and has reached out to our community in search of the necessary funding. Their crowdfunding program is running at Lifespan.io, with a recently added matching fund provided by LongeCity. Meanwhile, I and a few others have been working behind the scenes to help find other sources of funding for this project, an exercise that appears to be winding to a successful close, with all the necessary paperwork to be assembled over the next couple of weeks. Along the way I think we've managed to make a few promising new connections for the CellAge principals, expanding the likely reach of their work. We shall see how it goes. The good news is that the combined result of these efforts and the generosity of those who donated to the crowdfunding initiative means that only a little remains to be done in order to hit the original funding target. If you have a few dollars to spare and would like to help advance research and development to treat the causes of aging, feel free to jump in here to close the last of the funding gap.

CellAge: Targeting Senescent Cells With Synthetic Biology

Here at CellAge we believe it is a great thing to be healthy, capable and enjoying life at any age. We also believe that you deserve to have safe and effective medical treatments to make this happen, and this is why we are working hard to create breakthrough therapies that will treat one of the key reasons for age-related disease: senescent cells. The current methods scientists use to identify and remove senescent cells have many limitations such as being too large to use in present gene therapies, being too imprecise in the range of cells affected, or simply being incomplete in cell targeting and removal. CellAge is building a new senescent cell targeting system that overcomes these limitations through the development of synthetic promoters, special DNA sequences that can regulate the activity and expression of genes.

In short, CellAge is going to develop synthetic promoters which are specific to senescent cells, as promoters that are currently being used to track senescent cells are simply not good enough to be used in therapies. The most prominently used p16 gene promoter has a number of limitations, for example. First, it is involved in cell cycle regulation, which poses a danger in targeting cells which are not dividing but not senescent either, such as quiescent stem cells. Second, organism-wide administration of gene therapy might at present be too dangerous. This means senescent cells only in specific organs might need to be targeted and the p16 promoter does not provide this level of specificity. Third, the p16 promoter is not active in all senescent cells. Thus, after therapies utilizing this promoter, a proportion of senescent cells would still remain. Moreover, the p16 promoter is relatively large, making it difficult to incorporate in present gene therapy vehicles. Lastly, to achieve the intended therapeutic effect the strength of a p16 promoter to drive therapeutic effect might not be high enough.

CellAge will be constructing a synthetic promoter which has a potential to overcome all of the mentioned limitations. With your help, we will be able to use same technology to develop tools and therapies for accurate senescent cell targeting. We have teamed up with leading synthetic biology company, Synpromics, to create two new exciting systems for detecting and removing senescent cells. A number of gene therapy companies, including uniQure, AGTC and Avalanche have already successfully used similar technology to target other kinds of cells; we are confident we can do the same for senescent cells.

Our primary goal with this project is the creation of SeneSENSE, a new system that can overcome the limitations of other approaches and provide researchers with an accurate way to detect senescent cells. We predict this system could also be used as a quality control step in the stem-cell therapy manufacturing process to make cell therapies safer! As we want to foster the development of senolytic therapies, we plan to give SeneSENSE to other scientists for free, to help them improve their results. We aim to have our cell detection system ready by Q4 2017 enabling researchers to benefit in the near future and helping to speed up progress.

A Surprisingly Effective Polypharmaceutical Approach to Hypertension

That occasionally, very occasionally, quite effective results emerge from tinkering with existing drugs, and combinations thereof, is one of the reasons why people keep doing it, despite the fact that the overwhelming majority of the time the outcome is marginal at best. In the research here, a combination of existing blood pressure control drugs at lower doses is found to be considerably more effectively than any individual drug. Rising blood pressure with aging, hypertension, causes considerable damage through a variety of mechanisms to many organs, such as brain, heart, and kidney. Just as importantly, it accelerates the development of atherosclerosis to the point at which a vital blood vessel suffers catastrophic structural failure. Better control of blood pressure through pharmaceuticals is perhaps the most significant factor behind the reduced cardiovascular mortality of the past few decades, even though it has been achieved without addressing the fundamental cell and tissue damage that causes blood vessel stiffening and hypertension.

A small but clinically important trial of a new ultra-low dose four-in-one pill to treat high blood pressure has produced remarkable results. Every patient on the pilot trial saw their blood pressure levels drop to normal levels in just four weeks. Researchers said the results were exciting but larger trials were needed to see if these high rates could be maintained and repeated. "Most people receive one medicine at a normal dose but that only controls blood pressure about half the time. In this small trial blood pressure control was achieved for everyone. Trials will now test whether this can be repeated and maintained long-term. Minimising side effects is important for long-term treatments - we didn't see any issues in this trial, as you would hope with very low dose therapy, but this is the area where more long-term research is most needed. We know that high blood pressure is a precursor to stroke, diabetes and heart attack. The need for even lower blood pressure levels has been widely accepted in the last few years. So this could be an incredibly important step in helping to reduce the burden of disease globally."

Over four weeks 18 patients were either given a quadpill - a single capsule containing four of the most commonly used blood pressure-lowering drugs each at a quarter dose - or a placebo. This was then repeated for a further four weeks with the patients swapping their course of treatment. Blood pressure levels were measured hourly over a 24 hour period at the end of each treatment, allowing researchers to significantly reduce the amount of patients normally required in a clinical trial. 100 per cent of patients on trial saw their blood levels drop below 140 over 90. Just 33 per cent of patients on the placebo achieved this rate. None of the patients experienced side effects commonly associated with hypertension lowering drugs, which can vary from swollen ankles to kidney abnormalities depending on the type of class of the drug. "What makes these result every more exciting is that these four blood pressure medications are already in use. We are increasingly finding there are opportunities to treat many commons diseases hiding in plain sight. This ultimately means we will be able to deliver life changing medications much more quickly, and more affordably."

Link: http://www.georgeinstitute.org/media-releases/less-is-more-potential-breakthrough-for-treating-hypertension-with-ultra-low-dose

Thioredoxin versus Hypertension, a Demonstration in Mice

Hypertension, or rising blood pressure with age contributes to cardiovascular mortality, damage to sensitive kidney tissues, cognitive decline through blood vessel damage in the brain and other unwanted detrimental changes. It is thought to be largely caused by stiffening of blood vessels and other failures of the normal regulation of blood vessel constriction, which in turn is caused by cross-linking, inflammation, senescent cell presence, and so forth. Blood pressure is so influential a cause of downstream damage, however, that finding brute force ways to reduce it without touching on the actual causes is still significantly beneficial. A strategy of blood pressure control medication in later life has a considerable positive impact on mortality levels. So while it is comparatively inefficient as an approach in comparison to repair of the causes of blood vessel stiffening, it is nonetheless the case that a sizable fraction of the research community continues to work on ways to safely lower blood pressure without trying to address the causes of hypertension.

Hypertension is very common, especially in older adults, and it contributes to a number of other cardiovascular disorders. Although a variety of therapeutic interventions are available for this condition, none of them are specific or long-lasting, and they can all cause side effects, which decrease adherence to treatment. Researchers discovered that increased expression of thioredoxin, a protein that scavenges free radicals and restores proteins damaged by oxidation, reduced hypertension in mice. Injection of recombinant human thioredoxin also reduced hypertension in mouse models, and its protective effects lasted for weeks, suggesting that it may be possible to adapt this approach for chronic treatment of human patients.

The incidence of high blood pressure with advancing age is notably high, and it is an independent prognostic factor for the onset or progression of a variety of cardiovascular disorders. Although age-related hypertension is an established phenomenon, current treatments are only palliative but not curative. Thus, there is a critical need for a curative therapy against age-related hypertension, which could greatly decrease the incidence of cardiovascular disorders. We show that overexpression of human thioredoxin (TRX), a redox protein, in mice prevents age-related hypertension. Further, injection of recombinant human TRX (rhTRX) for three consecutive days reversed hypertension in aged wild-type mice, and this effect lasted for at least 20 days. Arteries of wild-type mice injected with rhTRX or mice with TRX overexpression exhibited decreased arterial stiffness, greater endothelium-dependent relaxation, increased nitric oxide production, and decreased superoxide anion generation compared to either saline-injected aged wild-type mice or mice with TRX deficiency. Our study demonstrates a potential translational role of rhTRX in reversing age-related hypertension with long-lasting efficacy.

Link: https://dx.doi.org/10.1126/scitranslmed.aaf6094

SENS after de Grey

A recent article on Aubrey de Grey, in which he is presented more in the mode of amiable fellow next door than the mode of instigator of the SENS rejuvenation research movement, reminded me that planned obsolescence is very much an anticipated goal for de Grey. He has for a while now seen a "retreat into glorious obscurity" ahead, perhaps wisely given the way movements tend to grow into unruly children, disrespectful of their founders. We'll see whether it actually comes to pass or not, given that a diet of interesting success is always a challenge to set to one side, but it is also true that going on two decades is a long time to be working what is essentially the same demanding, even consuming job. Still, look at folk like George Church and Craig Venter; there is no shortage of opportunity for third acts in this life. Note that the short article linked here is published by the Financial Times, and so you'll probably have to employ the usual stratagems to bypass their paywall; Google is your friend in this, at least.

Aubrey de Grey: scientist who says humans can live for 1,000 years

Fifteen years ago, de Grey was lead author of a paper in the Annals of the New York Academy of Sciences which claimed the "indefinite postponement of aging . . . may be within sight". Since then, he says, his position among gerontologists - the scientists of ageing and its related ills - has changed from sidelined dilettante to one of the discipline's most influential and public voices. While his science may now be more widely accepted, his pronouncements of impending immortality remain unpopular among his peers. Their squeamishness is unsupported by the evidence, he says. It belies an intellectual dishonesty that has at its heart a deeply emotional - and increasingly erroneous - attachment to the inevitability of death, according to de Grey.

In some ways de Grey's tumbledown mountain retreat seems a fitting castle for this self-appointed "spiritual leader of what I regard as the world's most important mission". To most eyes, the sprawling four-bedroom property falls on the wrong side of the line dividing shabby kitsch-and-chic from basic decrepitude. "The most expensive thing I had owned before this was a laptop. I don't like too much modernity and artifice, I like to be surrounded by mellow things." De Grey's asceticism amounts to more than a disregard for modern interiors and a voluminous beard. While many visionaries come to Silicon Valley to make a fortune, de Grey gave one away. In 2011, his mother - "the formative influence" of his life; his father left before he was born - died. De Grey, her only child, inherited her £10.5m fortune from two Chelsea houses she bought in 1953 and 1963 for a total, he estimates, of £30,000. De Grey took roughly £2.1m for himself, most of which, after inheritance tax, he spent on his home. The remainder, £8.4m, he donated to SENS. When his fiancée arrives he hopes, in time, to "retreat into glorious obscurity" with her, pulling back from a busy speaking schedule that takes him around the world to publicise his work.

It is in the nature of revolutions to bury those who led the first charge. The wages of wild success are indeed obscurity, and fighting that truth seems futile; a matter of standing against the tide. If you start a movement to change the world, and people can still easily pick you out from the crowd of change-makers and supporters fifty years later, then I'd say you didn't do so well. The point of the exercise is to create a sweeping wave of leaders, viewpoints, and endeavors that up-ends the present inadequate system to produce radical improvements. The point of the exercise is to make yourself irrelevant as rapidly as possible, in other words. Human nature being what it is, no matter how hard it was to convince the first few people, and no matter how much work was needed in the early days, the talking heads of the world will later agree that it was obvious in hindsight, anyone could have done it, and weren't those people in the second wave of activities, ten years in, far more important anyway? Validation in this scenario is something that you have to accomplish for yourself, which is worth thinking about while considering one's own efforts and future. Do the work because it is important to your eyes, and because you want to, not for any other reason.

It is true that there is a great deal left to accomplish in order to achieve the technical goal of robust mouse rejuvenation, through prototype implementations of therapies that repair the seven classes of cell and tissue damage that cause aging. The first such therapy, senescent cell clearance, seems a sure thing now, given the state of funding and the field. But the others? Still in the labs, some quite a way from realization. Still, SENS has won, the movement came into being. It is bigger than any one group of people, even now, while a sizable fraction of the necessary laboratory work remains coordinated by the SENS Research Foundation. The goals of SENS will survive the retirement or exodus of any given handful of people, and there are a number of alternative SENS-like formulations out there now, backed by their own advocates and researchers, such as the Hallmarks of Aging. The high-level concept of treating aging by reverting its distinct causes is now spread far enough not to fail. The next twenty years will be a matter of various viewpoints and implementations competing on the only metric that matters, which is the ability to produce rejuvenation in patients.

The battles of tomorrow will be fought over advancing the most plausible approaches more rapidly to the front of the queue, and obtaining the broadest possible funding and adoption by research groups. Later, the battles will be fought over ways to drive existing therapies into low-cost mass production, bypassing the existing regulatory system in favor of something simpler that will save vastly more lives, enabling widespread deployment of rejuvenation therapies both within and beyond the wealthier parts of the world as rapidly as possible. The very first seeds of that future are in progress today, but first things first. The construction of a new industry of rejuvenation biotechnology, from start to finish, is something that will span more than one career - though of course the hope is that it will not span more than a single lifetime, no matter how long it takes. Those who finish will be vastly more numerous, and an entirely different set of people, from those who start. That is the way of things.

Searching the Lizard Genome for Regenerative Factors

Some of the research aimed at understanding - and potentially replicating - the greater regenerative capacity of lizards is fairly reductionist in nature. The genome is sequenced for a lizard species, the proteome cataloged, and then compared with mammalian biochemistry in search of possibly interesting differences for further examination. This open access paper summarizes one such finding, and the background behind it:

It is likely that all animals have the capacity to regenerate damaged body parts, although the degree of regeneration seems to be different in different species. Regeneration is more vigourous in invertebrates than it is in vertebrates. Indeed, many invertebrates, such as hydra, planarians, and starfish, have bidirectional regeneration capcity, so they can generate two sets of the same animal by regrowing missing parts, while regeneration processes in vertebrates occur unidirectionally, in which the animal reproduces only damaged parts at the site of injury. Amongst vertebrates, fishes and amphibians have the greatest regenerative capacities, and amniotes such as reptiles, birds, and humans, seem to have lost the capability to regenerate, although many lizards can reproduce their tails.

In lower vertebrates, natural regeneration occurs mainly by virtue of the intrinsic plasticity of mature tissues, which involves cellular proliferation, migration of remaining parts, and regrowth of damaged or missing parts. The most prominent event in tissue regeneration in lower vertebrate may be formation of a blastema. The blastema shares many characteristics with stem cells, and can eventually redevelop into various tissues, including muscle, skin, bone, and blood vessels, that were originally present at the damaged site. The blastema is formed through the dedifferentiation process, and this step is omitted in the higher vertebrates such as birds and mammals. Thus, it could be that the lack of regenerative capacity in birds and mammals may be evolutionarily related to loss of the capacity to dedifferentiate.

In fact, mammals share many key factors for regeneration with lower animals, such as fibroblast growth factor (FGF), Wnt/beta-catenin, and bone morphogenic protein (BMP)/Msx signaling, which are known to be involved in wound healing and cellular proliferation. Through such processes, mammals can repair damaged tissues to some extent. Nevertheless, mammals have little regenerative capacity compared to lower animals, probably because they lack the capability to dedifferentiate. Damage to human organs, such as the heart, brain, and liver, often leads to serious pathological conditions. Although stem cell-based transplantation could be clinically performed, additional strategies may be required for proper treatment of organ injuries in humans. Thus, study of the mechanisms of blastema formation and the development of protocols for mammalian dedifferentiation will be a breakthrough for regenerative medicine and stem cell biology.

Mammalian cells have been known to undergo dedifferentiation in vitro by enforced expression of Oct4, Sox2, Klf4, and c-Myc. Although this induced pluripotent stem cell (iPSC) strategy is an innovative tool in human tissue regeneration and stem cell therapeutics, it has drawbacks including low efficiency and uncertain safety. For example, use of oncogenes such as Klf4 and c-Myc in iPSC generation raised concerns about the safety of iPSCs for practical applications. Although other substitutes such as Nanog and Lin28 have been suggested, these oncogenes may be regarded as indispensable to the efficiency of dedifferentiation. The first gene identified as a dedifferentiation factor from proteomic studies in lizards was a lactoferrin. Recent discoveries showed that lactoferrin can substitute for Klf4, and even provide greater efficiency for dedifferentiation of human fibroblasts. Although lactoferrin by itself is not enough to replace all the oncogenes necessary for dedifferentiation of human cells, and further identification of other factors should be performed, this finding indicates that comparative studies of lizards would be a promising strategy to reveal the mechanisms of regeneration.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5070703/

A Call for More Study of Exceptionally Regenerative Species

A range of higher animal species are capable of regrowing organs and limbs, such as the zebrafish and axolotl. Research groups have for some years investigated the differences between the biochemistry of these species and mammals, and given the promising progress to date, the authors of this commentary call for an increased investment in this field:

Increasingly more studies of nontraditional vertebrate model organisms with extraordinary regenerative capacities are providing valuable insight into the mechanisms of complex tissue regeneration. For example, the zebrafish (Danio rerio) can regenerate many tissues after injury including cardiac, fin appendages and spinal cord. Another ray-finned fish, the bichir (Polypterus senegalus) can also regenerate cardiac and fin appendages. Urodeles (salamanders and newts), such as the axolotl (Ambystoma mexicanum), can regenerate whole limbs. Studies of models with robust regenerative capacities have advanced our understanding of regenerative mechanisms by identifying genes that are necessary and sufficient for regeneration in vivo. Regenerative biology has historically focused on defining the cellular and molecular mechanisms within individual species. Within the last 15 years, rapid advances in genome sequencing technology and gene editing strategies have advanced the understanding of the molecular and cellular processes that define tissue regeneration. Unfortunately, they have also unintentionally created silos that encase individual animal models and discourage examination of regenerative capacity in nontraditional model systems.

Comparative studies of regeneration can be framed in a phylogenetic context where model organisms are selected to identify conserved gene regulatory mechanisms for regeneration. These limb regeneration traits are in stark contrast to mammals where it is limited to the very ends of digits in mice, rats, monkeys, and humans. Given that urodele taxa can regenerate limbs, it suggests that limb regeneration is an ancestral trait of urodeles. Furthermore, it is plausible that appendage regeneration is an ancestral trait of all jawed vertebrates as both ray-finned fish and urodele taxa can regenerate appendages. Alternatively, limb regeneration may be a derived trait. No reports of appendage regeneration have been published among cartilaginous fishes (chondrichthyes). The last common ancestor of jawed vertebrates appeared approximately 420 million years ago providing for an opportunity to find common mechanisms for appendage regeneration.

With increasing knowledge of proregenerative mechanisms, the next challenge is to identify small molecules to enhance regeneration following injury in humans. A target-based strategy where compounds are identified to target particular genes, proteins or pathways is a complementary strategy. Proregenerative lead compounds could then be tested in nonregenerative models, such as the mouse, to determine whether they promote regeneration. The demonstrated benefits of studying the genetic pathways for regeneration in highly regenerative species should motivate us to re-examine the allocation of research funds. Additional investment to create genetic and molecular resources to study nontraditional models, such as the zebrafish and axolotl, are needed to accelerate these comparative studies. The zebrafish represents a good start, its genome was characterized in 2003 and many genetic tools have been developed to work with it, which are already yielding fruit. The progress on therapies for heart regeneration, for instance, has been 'spectacular', according to researchers who discovered in 2002 that zebrafish can regenerate heart tissue after 20% of the ventricle has been removed.

Other model organisms are still unexploited, however. High levels of research funding using mouse models over several decades have built a vast repertoire of tools and resources for the mouse. Currently, over 70% of traditional research grants involve mouse studies. Increasing funding for studies that involve a broader set of model organisms, like the zebrafish and axolotl, across all biomedical fields would result in more tools and resources for these diverse models. In turn, these investments would provide the critical genetic and molecular tools and resources for nontraditional model organisms needed to accelerate comparative studies of regeneration.

Link: https://dx.doi.org/10.2217/rme-2016-0159

The Transhumanist Advocacy of Zoltan Istvan

During the recent presidential election, Zoltan Istvan chose to use one of the few potentially vaguely effective opportunities for grassroots advocacy via the US political process, and put himself forward as a candidate. The goal in doing this was much the same as for the early stages of any single issue political party in a European country, which is to say to leverage the media attendant to the political process in order to put out a message, rather than to actually win anything. Istvan and I are both transhumanists, as is much of the audience here, though I'd say that he is more ready to make that a brand rather than a common sense description of philosophical leanings.

We would both agree that progress in technology will enable our species to overcome the most important limits on the human condition, particularly aging to death, and that this is both plausible and desirable. The sooner it happens the better, but there is all too little public support for such goals at present, despite a considerable growth in the awareness of transhumanist ideals. The longevity science advocacy community of today is very much the cultural descendant of the transhumanist communities twenty years past, for example. Their ideas, once niche and radical, became a portion of the mainstream, some more rapidly than others, such as those involving artificial general intelligence and molecular manufacturing. Support for the use of biotechnology to bring an end to aging is only now arriving at the same place reached by those other fields, a decade later.

It is true, as recent commenters have noted, that I do not often write about politics. Firstly, who needs yet another person doing that? Secondly, insofar as I have a position on politics, I am against it. It is a poisoned chalice that drags down people who might otherwise have been productive, ensnaring them in corruption, waste, and endless, pointless distraction from what actually matters in life. Politicking is an undertaking of no consequence in comparison to the work of building new technology. The state of technology is what determines society, determines the shape of life, offers us new possibilities. In this picture the squabbles of politicians and their devotees are little more than background noise, as demonstrated by how soon today's crises and marches are lost to memory. If we want a better future, history teaches us that the most reliable way to achieve that goal is to choose to build better medicine, better computational devices, better means of transport, and all of the other implementations of scientific knowledge that make being alive a greater thing than it was before, more rich and full of possibility. Not talk about it, not debate funding bills, not distribute stolen largess from the public purse, but to actually set out and do it, as entrepreneurs and investors.

I have the greatest of admiration for someone such as Istvan, who has certainly devoted more time and energy than I of late to set out to persuade people to support the goal of an end to aging through medical research. I just wish he'd chosen a different approach to the problem of efficient advocacy, or perhaps that he was more focused on rejuvenation biotechnology after the SENS model. We don't get to direct the preferences of our fellow travelers, of course, but still. Politics is not the place to go if you want to change the world. It is the place to go if you want to boldly declare that you no longer have any good idea as to how to change the world for the better, and that the sum of your ambitions have become a matter of forcefully rearranging what is, rather than creating new wonders and improvements for the future.

600 Miles in a Coffin-Shaped Bus, Campaigning Against Death Itself

In the autumn of 2015, a man of my acquaintance purchased a 38-foot recreational vehicle - a 1978 Blue Bird Wanderlodge - and, having made to this vehicle such modifications as would lend it the appearance of a gigantic coffin, set out to drive it eastward across the great potbellied girth of the continental United States. His reasons for doing so were, in certain respects, complex and conflicting, but for now it will suffice to inform you that this voyage was undertaken in order to raise awareness of two distinct but related matters. The first of these was the regrettable fact of human mortality and the need to do something about it; the second was that of his candidacy in the following year's presidential election.

This man's name was Zoltan Istvan, and I had known him for about a year and a half by the time he began his progress across the country, from the Bay Area, where he lived, to Florida, and thence northward to Washington, where he planned to ascend Capitol Hill and, in coy allusion to Martin Luther's delivery of his 95 Theses, affix a Transhumanist Bill of Rights to the great ornate bronze door of the Rotunda. "It will be my way of challenging the public's apathetic stance on whether dying is good or not. By engaging people with a provocative, drivable giant coffin, debate is sure to occur across the United States and hopefully around the world. I'm a firm believer that the next great civil rights debate will be on transhumanism: should we use science and technology to overcome death and become a far stronger species?" For transhumanists, this could only be conceived of as a rhetorical question, the obvious answer to which was a resounding yes. I had spent the previous 18 months immersed in this diffuse and heterogeneous movement, through which I encountered many forms of radical optimism about the potential for technology to transform the human condition, to improve our bodies and minds to the point that we become something better.

I met Istvan on a Friday morning outside an empty secondhand bookstore in Las Cruces, N.M, accompanied by Roen Horn. I asked him how he wound up volunteering for Istvan's campaign. "I just really don't want to die," he said. "I can't think of anything that would suck more than being dead. So I'm just doing what I can to ensure that life-extension science gets the funding it needs." Horn, with his Calvinist background, seemed to me now a walking illustration of the way in which scientific progress had displaced divine providence as our culture's locus of faith. Istvan, by contrast, had come to transhumanism from a more secular background. While reporting on the large number of buried land mines still remaining in Vietnam's former DMZ, Istvan himself came very close to stepping on one. In the narrative he had constructed about his life, this was the moment he became a transhumanist - the moment he became consumed by an obsession with mortality, with the unacceptable fragility of human existence. "I have to admit," I said, "I find this whole immortality thing difficult to get behind. Doesn't your obsession with living eternally actually amount to your being totally imprisoned by death?" Horn said "Maybe, but aren't we all? Isn't that kind of the whole idea?" I told him that I took his point.

At the end of the day, progress towards the future of working rejuvenation therapies is built one step at a time. There must be persuasion, philanthropy, and investment alongside the necessary work undertaken by researchers. But ultimately, this progress is a mosaic built from individual choice, a great many people each choosing of their own volition to take a step in that direction. It is all too easy for those on the outside to look at any one particular step and and feel it is insignificant in the face of the work required to reach future goals, but all efforts contribute to the whole.

Early Coronary Artery Calcification Predicts Later Risk of Heart Disease

Researchers here find that even quite low levels of calcification of arteries at younger ages associates with a raised risk of heart disease going forward. Calcification is a process that has is yet to be firmly placed in the chain of cause and consequence for age-related damage in blood vessel tissues. The evidence leans towards it being a consequence of primary damage such as waste accumulating in cell lysosomes, forms of persistent cross-linking that stiffen blood vessels and senescent cell accumulation that produces inflammation, insofar as growing calcification appears to be a cellular process, the result of changed and inappropriate cellular behavior. So in this sense, calcification is a marker of the progression of damage in aging, and more of it should absolutely be expected to correlate with the risk of age-related disease.

Researchers have found that the mere presence of even a small amount of calcified coronary plaque, more commonly referred to as coronary artery calcium (CAC), in people under age 50 was strongly associated with increased risk of developing clinical coronary heart disease over the ensuing decade. The study also revealed that those with the highest coronary artery calcium scores, as measured by computed tomography (CT) scan, had a greater than 20 percent chance of dying of a heart event over that same time period. CAC has long been associated with coronary heart disease and cardiovascular disease. However, prognostic data on CAC in younger adults - people in their 30s and 40s - have been very limited.

"We always thought you had to have a certain amount of this plaque before you were at risk of having events. What our findings demonstrate is that, for women and women less than 50 years of age, any amount of coronary artery calcium significantly increased risk of clinical heart disease. Any measurable CAC in early middle age - scores of less than 100, and even less than 20 - has a 10 percent risk of acute myocardial infarction, both fatal and non-fatal, over the next decade beyond standard risk factors." The study points to CAC as a very specific imaging biomarker for identifying those people who are at risk earlier in life for heart disease, and who may benefit from proven interventions such as cholesterol and blood pressure management, working toward a healthy BMI and smoking cessation, although more work is needed.

Data for this study comes from the Coronary Artery Risk Development in Young Adults (CARDIA) Study, a longitudinal, community-based study that recruited 5,115 black and white adults ages 18-30 in four cities - Oakland, California; Minneapolis; Chicago; and Birmingham, Alabama - beginning in 1985 and followed them for 30 years. CT scans were performed on 3,330 subjects for the CAC study, and the mean follow-up period was 12.5 years. CAC of any amount was seen in 30 percent of that group. Investigators sought to answer two primary questions: can the simple presence of CAC on a chest CT inform clinical practice? And is a CAC score greater than 100 associated with premature death? The answer to both was yes. "The presence of any coronary artery calcification, even the lowest score, was associated with between a 2.6 and tenfold increase in clinical events over the next 12.5 years. And when it comes to those with high CAC scores (100 or above), the incidence of death was 22 percent, or approximately 1 in 5. Very few times do you get a biomarker, be it genetic or imaging, that predicts death at a level of 22 percent over 12.5 years."

Link: https://news.vanderbilt.edu/2017/02/08/study-shows-presence-of-any-calcified-plaque-significantly-raises-risk-of-heart-disease-for-people-under-age-50/

An Indirect Test to Assess Risk of Cardiac Transthyretin Amyloidosis

Researchers have only recently started to understand the degree to which transthyretin amyloidosis contributes to heart failure. This condition is thought to be a majority cause of death in the very oldest people, but there is now evidence to show that heart disease in earlier old age is also caused by a build up of this form of amyloid in tissues. The growing presence of various amyloids is one of the fundamental differences between old tissue and young tissue, and any future rejuvenation toolkit must include the means to remove them. Since there is at least one viable clearance treatment under development for transthyetin amyloid, that worked on at Pentraxin Therapeutics, an important next step in the process of raising the funds needed to complete passage through the heavy-handed regulatory systems of the US and Europe is to gather more evidence of the need for such a therapy. That in turn requires better clinical tests, or indeed any viable clinical tests, as at present the evidence for transthyretin amyloid to cause heart disease is largely obtained from post-mortem studies. Here, researchers report on progress towards an indirect approach to testing for the risk of this form of amyloidosis in heart tissue:

Researchers have developed a new diagnostic test that may help doctors identify patients with a condition called cardiac amyloidosis. Cardiac amyloidosis is caused by abnormal folding of proteins that deposit in the heart. These protein deposits can also occur in other organ systems in the body and can cause life-threatening organ failure. Cardiac amyloidosis that results from the mis-folded protein transthyretin is called ATTR amyloidosis, and this form of the disease occurs in older patients. Amyloid deposition can cause electrical abnormalities and decrease the heart's ability to relax and contract, leading to congestive heart failure.

The diagnosis of ATTR amyloidosis can be challenging for doctors, and amyloidosis in many patients remains un-recognized, sometimes until the time of death. However, recent studies suggest that as many as 10 percent of older patients with certain types of congestive heart failure may have cardiac amyloidosis. In this study, researchers identified that a specific blood protein named retinol-binding protein 4 (RBP4) can be used to determine the likelihood of ATTR amyloidosis in a patient with congestive heart failure.

In addition the research team developed a mathematical calculator that incorporates RBP4 and other commonly ordered clinical tests that can be used to estimate the probability of ATTR amyloidosis in a given patient. An important advantage of this algorithm is that it can be used in the context of a doctor's office visit at the point-of-care. According to the researchers, this discovery could guide clinical decision making and increase recognition of this disease. Since many new drug therapies are in various stages of development now for ATTR amyloidosis, recognition and accurate diagnosis is essential to get a patient on the correct treatment.

Link: https://www.eurekalert.org/pub_releases/2017-02/bumc-otd020717.php

GPER Knockout Reduces Oxidative Stress to Slow Cardiovascular Aging

In the research noted below, scientists report on the discovery that loss of the GPER gene can slow the pace at which cardiovascular disease progresses, albeit only modestly. Since the molecular biochemistry of a cell is so intertwined, and any given mechanism can be influenced by the presence or absence of numerous different proteins, the existence of any one demonstration of this nature means that should expect there to be a fair number of genes and proteins that might have similar effects if manipulated. Equally, we should also expect most to have only small effects, or to also have unwanted side-effects that make them unsuitable targets for comparatively blunt and sweeping operations such as gene knockout. Most proteins have numerous different roles in cellular processes, which makes it rare to find one that can be removed entirely. Thus the real interest occurs when it is demonstrated that a gene can indeed be done away with without ill effects, an entirely beneficial change - as is the case for PCSK9, mentioned yesterday, among others.

Considering the existence of beneficial mutations, one has to concede that evolution has gifted mammals with a genome that is suboptimal in many ways. Researchers have discovered single gene alterations that increase muscle mass, improve cellular housekeeping, make metabolism work better over the long term, reduce cardiovascular disease, and so forth. That these single gene alterations are there to be developed into a near future of enhancement gene therapies is one of many indications that evolutionary fitness doesn't correspond all that well to individual advantage. Natural selection favors an inferior model, or at least inferior when considered from the vantage point of being someone who is stuck with a body and biochemistry laboriously produced in this manner. Aging itself is the largest of our problems, and may well result from an evolutionary arms race to the bottom; one view of the evolutionary theory has it that aging helps species adapt to changing environments, and since the world does indeed change, the result is that near every present and historical species is made up of individuals who age to death. The immortals were out-competed, save for a few remnants here and there, such as hydra.

Researcher Discovers New Class of Drugs to Combat Aging Diseases

G protein-coupled estrogen receptor, or GPER, determines in part how our cells respond to the hormone estrogen and to estrogen-like substances. GPER plays a role in diseases like breast cancer and diabetes, but also mediates many beneficial functions in physiology. Researchers found that making GPER more active in mice placed on a high fat diet reduced the development of atherosclerosis, a condition in which the blood vessels harden and narrow. But another study's results with old mice were a surprise. The researchers observed mice that lacked GPER in all their cells as they aged. They tracked the mice over the normal mouse life span of about two years. They expected these mice to show increased levels of aging-related disease in their hearts and blood vessels. Instead, compared with normal aged mice, the GPER-lacking mice had healthier hearts and blood vessels. The team then conducted a series of experiments to learn why. They discovered an altered balance between certain signaling molecules in the smooth muscle cells of blood vessels and the heart.

One of those signaling molecules, superoxide, is a type of reactive oxygen species. Reactive oxygen species react quickly and strongly with nearby cellular proteins and impede those proteins' ability to perform their tasks. Over time, the cell's proteins and other components degrade enough to prevent normal cell functions. Almost every disease of aging is influenced by reactive oxygen species. The researchers next tested whether a GPER-blocking drug would improve smooth muscle cell function, as they observed in cells lacking GPER. They discovered that blocking GPER changed how the blood vessels' smooth muscle cells expressed their genes. One of the genes that the drug affected produces a protein called NOX1. NOX1 produces superoxide, one of the most reactive molecules the body produces. By blocking GPER, the team's drug also blocked NOX1 expression, reducing the amount of superoxide the cell produced and reducing cellular aging. The blood vessels of people, and mice, with chronic diseases like diabetes, heart disease and cancer show signs of accelerated aging. By preventing NOX1 expression to block a cell from producing excess superoxide, researchers hope to find a treatment for these conditions one day.

Obligatory role for GPER in cardiovascular aging and disease

Ligand-dependent activation of the G protein-coupled estrogen receptor (GPER) has been reported to confer cardiovascular benefits. However, we found that genetic absence of Gper conferred protection from cardiovascular pathologies associated with aging and hypertension. GPER activity was required to increase the abundance of the enzyme Nox1 in vascular smooth muscle cells, blood vessels, and myocardium, and was associated with enhanced production of tissue-damaging superoxide. Aged mice that were deficient in Gper developed much less cardiac fibrosis and hypertrophy and also retained greater cardiovascular function. In addition, a pharmacological inhibitor of GPER reduced blood pressure, superoxide production, and Nox1 abundance in hypertensive mice. Thus, inhibitors of GPER are potential therapies for cardiovascular diseases and conditions characterized by excessive superoxide generation. Our results indicated that GRBs represent a new class of drugs that can reduce Nox abundance and activity and could be used for the treatment of chronic disease processes involving excessive superoxide formation, including arterial hypertension and heart failure.

Too Many People Think of Aging and Age-Related Diseases as Somehow Distinct

There is a lot of confused thinking out there in the world when it comes to aging and age-related disease. You don't have to look much further than the fact that most people are entirely supportive of research to treat and cure age-related diseases, such as cancer, heart disease, and Alzheimer's, but those very same people are not in favor of treating aging as a medical condition in order to extend healthy life spans. Yet the progression of aging and the development of age-related disease are one and the same process, meaning the accumulation of biological damage and its consequences to the operation of cells and tissues. The only way to prevent age-related disease is to control that damage, keep it down to a low level by periodically repairing it. Given sufficiently comprehensive repair therapies, undergoing treatment will also put a halt to aging, even produce rejuvenation. The goal of curing age-related diseases across the board necessarily means extension of healthy life; absent damage, people will continue in vigor and good health indefinitely. Unfortunately, most people are disinclined to support the only feasible approach that can achieve this goal.

If you've ever tried to advocate for rejuvenation, you know it is hard. Usually, people deem the idea as crazy, impossible, or dangerous well before you get to finish your first sentence. Living too long would be boring, it would cause overpopulation, 'immortal' dictators, and what have you. However, you've probably never heard anyone use the same arguments to say that we should not cure individual age-related diseases. This is largely because people have little to no idea about what ageing really is, that it cannot be untangled from the so-called age-related pathologies. These are nothing more, nothing less, than the result of the life-long accumulation of several types of damage caused by the body's normal operations. Unlike infectious diseases, the diseases of old age are not the result of a pathogen attack, but essentially the result of your own body falling apart. As I was saying, people are largely unaware of this fact, and therefore expect that the diseases of ageing could be cured one by one without having to interfere with the ageing process itself, as if the two weren't related at all. The result of this false expectation would be that you could cure Alzheimer's, Parkinson's, and so on, but somehow old people would still drop dead around the age of 80 just because they're old.

That is like saying that people will die of being healthy. Back to reality, this can't be done. To cure the diseases of old age, you need to cure ageing itself. If, for whatever reason, you think that curing ageing as a whole would be a bad idea and it should not be done, the only option is to not cure at least some of the root causes of ageing. Consequently, some age-related pathologies would remain as untreatable as they are today. The typical objections raised against rejuvenation tend to sound reasonable at first. To some, the statement 'We should not cure ageing because it would lead to overpopulation' sounds self-evident. However, if we consider the implications of this statement, things start getting crazy. As said, not curing ageing implies not curing some of its root causes, which in turn implies not curing some age-related diseases. Therefore, the sentence 'We should not cure ageing, because otherwise fewer people would die and this might lead to overpopulation' implies 'We should not cure Alzheimer's disease, because otherwise fewer people would die and this might lead to overpopulation.' I don't think I need to point out why that statement is utterly ridiculous. I'm all for discussing potential problems brought about by the defeat of ageing, so that we can prevent them from ever happening; however, I'm not going to buy a pig in a poke and accept blatant nonsense as valid objections to rejuvenation.

Link: https://rejuvenaction.wordpress.com/2017/02/02/reductio-ad-absurdum/

Reviewing Methionine Restriction as a Basis for Calorie Restriction Benefits

The practice of calorie restriction has been shown to extend life in most mammalian species tested, including primates, and to at least greatly improve measures of health in humans. There is some consensus for the primary mechanism of calorie restriction to involve sensing of methionine levels in the diet, as feeding animals a normal level of calories using foods that contain very little methionine produces fairly similar outcomes to those observed in calorie restricted animals. Methionine is one of the essential amino acids, those not manufactured by our biochemistry and which must be obtained via the diet. It is required for synthesis of proteins, and so less of it requires cells to recycle more aggressively, among other changes.

Methionine restriction (MR) extends lifespan across different species. The main responses of rodent models to MR are well-documented in adipose tissue and liver, which have reduced mass and improved insulin sensitivity, respectively. Recently, molecular mechanisms that improve healthspan have been identified in both organs during MR. In fat, MR induced a futile lipid cycle concomitant with beige adipose tissue accumulation, producing elevated energy expenditure. In liver, MR upregulated fibroblast growth factor 21 and improved glucose metabolism in aged mice and in response to a high-fat diet. Furthermore, MR also reduces mitochondrial oxidative stress in various organs such as liver, heart, kidneys, and brain. Other effects of MR have also been reported in such areas as cardiac function in response to hyperhomocysteinemia, identification of molecular mechanisms in bone development, and enhanced epithelial tight junction. In addition, rodent models of cancer responded positively to MR, as has been reported in colon, prostate, and breast cancer studies.

The beneficial effects of MR have also been documented in a number of invertebrate model organisms, including yeast, nematodes, and fruit flies. MR not only promotes extended longevity in these organisms, but in the case of yeast has also been shown to improve stress tolerance. In addition, expression analyses of yeast and Drosophila undergoing MR have identified multiple candidate mediators of the beneficial effects of MR in these models. In this review, we emphasize other in vivo effects of MR such as in cardiovascular function, bone development, epithelial tight junction, and cancer. We also discuss the effects of MR in invertebrates.

Link: https://dx.doi.org/10.1016/j.exger.2017.01.012

Towards PCSK9 Gene Therapy to Reduce Cardiovascular Disease Risk

The popular science article I'll point out today is indicative of the movement towards enhancement gene therapies that is taking place across the research community. More slowly in some parts than in others, but there is movement nonetheless. The enabling technologies for mammalian gene therapy have fallen greatly in cost and increased greatly in reliability over the past decade, culminating with the comparatively recent advent of CRISPR gene editing approaches. It is is thus perfectly feasible to discuss development of human gene therapies at this time, as the only remaining aspect to be brought up to the desired level of quality is the degree of cell and tissue coverage achieved by the therapy - how many cells are altered, and whether or not stem cells are altered in order to make the change more permanent. At the moment this coverage is quite variable and uncertain, so better methodologies are needed. Nonetheless, human gene therapy is possible, a few people have undergone enhancement treatments, and at the present time I'd say it is the heavy hand of regulation and a related timidity among researchers and clinicians that are the chief obstacles to be overcome.

Elective gene therapy for enhancements to the present human genome is a potentially enormous market. Unlike medicine for sick people, who comprise a small percentage of the population, this is medicine for every adult - a far greater number of individuals. So I don't believe that current regulatory stances will hold up in the face of medical tourism, not when the actual technologies are now so easily implemented by small groups. At present there are perhaps half a dozen genes for which there is enough evidence enough to feel comfortable of the safety profile of gene therapies: either existing human mutants, or animal lineages, or a great deal of research to support the alteration in question, achieved through ways other than gene therapy, such as antibody blockade of the protein produced from the genetic blueprint. That number will grow in the years ahead. The best candidates are follistatin overexpression and myostatin knockout for muscle growth and associated improvements in metabolism; there is an enormous amount of evidence in mammals for the benefits here.

Beyond this, interventions for some of the other promising genes have been observed in human and mouse mutants to significantly reduce the level of cholesterol in the bloodstream, and thus also significantly reduce cardiovascular disease incidence, with no negative side-effects. One of these is PCSK9, under discussion below, and another is ASGR1. Lowered cholesterol level is one way to reduce the impact of oxidatively damaged cholesterol on the walls of blood vessels, and thus slow the progression of atherosclerosis. This condition is essentially a positive feedback loop of tissue disruption and growth of fatty deposits in blood vessel walls, involving cholesterol, inflammation, inappropriate cell signaling, and malfunctioning immune cells. The more that any of these line items are present, the worse the situation. Interventions in any of these loop components can help to damp down the risk and pathology of atherosclerosis.

Injection could permanently lower cholesterol by changing DNA

People born with natural mutations that disable a specific gene have a lower risk of heart disease, with no apparent side effects. Now a single injection has successfully disabled this same gene in animal tests for the first time. This potential treatment would involve permanently altering the DNA inside some of the cells of a person's body, so doctors will have to be sure it is safe before trying it in people. But the benefits could be enormous. In theory, it could help millions live longer and healthier lives. The results of the animal study were described by Lorenz Mayr, of pharmaceutical firm AstraZeneca, at a genomics meeting in London. Mayr, who leads the company's research into a DNA editing technique called CRISPR, wouldn't say whether AstraZeneca plans to pursue this approach, but he was clearly excited as he presented the findings. "The idea would be to do it as a one-off. It should be permanent."

The PCSK9 protein normally circulates in the blood, where it degrades a protein found on the surface of blood vessels. This second protein removes LDL cholesterol from the blood: the faster it is degraded by PCSK9, the higher a person's cholesterol levels. But people who lack PCSK9 due to genetic mutations have more of this LDL-removal protein, and therefore less cholesterol in their blood. "They have a lower incidence of cardiovascular disease and no apparent side effects whatsoever." To mimic this effect, two companies have developed approved antibodies that remove the PCSK9 protein from the blood. These are very effective at lowering cholesterol and no serious side effects have been reported so far. It is yet to be shown if they reduce the risk of cardiovascular disease, but the first trial results are due to be announced in March.

However, the antibody drugs are extremely expensive and need to be injected every two to four weeks, so even if the antibodies work as well as hoped, they cannot be dished out to millions like statins. All attempts to develop conventional drugs to block PCSK9 have failed, but gene editing provides a radical alternative. Using the CRISPR technique, the team at AstraZeneca have disabled human versions of the PCSK9 gene in mice. They did this by injecting the CRISPR Cas 9 protein and a guiding RNA sequence into the animals. The RNA guide helps the Cas9 protein bind to a specific site in the gene. It then cuts the gene at that point, and when the break is repaired, errors that disable the gene are likely to be introduced. The big worry about using gene editing to alter DNA inside the body is that it could also cause unintended "off-target" mutations. In the worst case, these could turn cells cancerous. Mayr says the team has tested for off-target effects in 26 different tissues in the mice, and that the results will be published soon. "It's very promising in terms of safety."

An Apparent Limit on the Quality of Longevity Therapies is Only a Statistical Artifact

Some time ago, statistical correlations in mortality data were used to suggest that interventions that reduce early mortality would lead to later accelerated aging. This view has become fairly widespread in aging theory, and we can see its echoes in studies that provide evidence for early physical prowess to correlate with faster aging, to pick one example. Not everyone agrees, however. Researchers here provide evidence to show that this relationship is an artifact of statistical methods, and there is thus no underlying physical basis for such an outcome. This in turn means that researchers should not be concerned in forging ahead to build therapies to reduce mortality at all ages.

The Strehler-Mildvan correlation was reported in 1960 in a now-famous and very well cited paper. It relates to the Mortality Rate Doubling Time (MRDT) and Initial Mortality Rate (IMR), two parameters of Gompertz mortality law. The original paper does not only introduce the empirical correlation, but also provides a sophisticated theory of aging behind it that is widely accepted among researchers. It says that if the mortality rate is reduced by any interventions at an earlier age, the MRDT goes down, i.e aging accelerates. This hypothesis leads to obstructions to the development of anti-aging therapies and makes optimal aging treatments impossible. Over years, quite a few researchers expressed doubts whether there was any biological meaning behind this correlation or not.

The Gero team prefers to use evidence based science approach over machine learning techniques for anti-aging therapies design, focused on physical reasoning behind mortality dependence on biologically available signals, ranging from gene expression to locomotor activity. Trying to determine physical processes behind Strehler-Mildvan correlation, the team noticed the fundamental disagreement between analytical considerations and possibility of SM correlation for Gompertz mortality law. They showed that SM correlation arises naturally as a degenerate manifold of Gompertz fit.

"We worked through the entire life histories of thousands of C.elegans that were genetically identical, and the results showed that this correlation was indeed a pure fitting artifact. The problem is not as complicated for worm experiments, though it gets pretty tough if humans are involved (the ratio of Gompertz slope to IMR is too large). Thus it seems like SM correlation is an artifactual property of the fit, applied in a limit where the fit does not work, rather than a biological fact. Elimination of Strehler-Mildvan correlation from theories of aging is good news, because if it was not just a negative correlation between Gompertz parameters, but a real dependence, it would have removed the potential for optimal anti-aging interventions and limited human possibilities for life extension."

Link: https://www.eurekalert.org/pub_releases/2017-02/g-eot020617.php

SENS Research Foundation and Buck Institute to Collaborate on a New Approach to Clearing Neurofibrillary Tangles

The SENS Research Foundation staff have over the past decade pioneered the field of medical bioremediation, mining the bacterial world for enzymes capable of breaking down the various forms of metabolic waste associated with aging and age-related disease. Suitable enzymes can form the basis for rejuvenation therapies that work via clearance of these waste products, and thus far the SENS teams have spun off the results of their work into development programs at Human Rejuvenation Technologies, to treat atherosclerosis, and Ichor Therapeutics, to treat macular degeneration. Today the SENS Research Foundation announced a new collaboration with the Buck Institute for Research on Aging in order to apply this same approach to the clearance of altered forms of tau protein that cause harm in Alzheimer's disease and other tauopathies. Much of present day Alzheimer's research focuses on clearance of amyloid, but it is becoming clear that both amyloid and tau aggregates are involved in the pathology of the condition. Unfortunately, while there are some signs of progress, work on tau clearance lags years behind the efforts put into amyloid clearance. Here is a chance for that side of the field to catch up:

The SENS Research Foundation (SRF) has launched a new research program in collaboration with the Buck Institute for Research on Aging. A leading expert on age-related neurodegenerative diseases will be leading the project in the Andersen lab at the Buck. The program is focused on the formation of tau tangles in the progression of neurodegenerative diseases. It will explore the elimination of these age-related waste products in brain cells, using the same approach that SRF has applied in its atherosclerosis and macular degeneration research projects in recent years. The Andersen lab will bring its own world-leading expertise in age-related neurodegeneration to the project. "Our ultimate goal is to find treatments for Alzheimer's and Parkinson's disease. Working with SRF will enable us to look at whether it is possible to use a new method to reverse and prevent the formation of tau tangles, which will help us make significant progress in addressing these complex disorders."

This research has been made possible through the generous support of the Forever Healthy Foundation and its founder Michael Greve, as well as the support of our other donors. The Forever Healthy Foundation is a private nonprofit initiative whose mission is to enable people to vastly extend their healthy lifespans and be part of the first generation to cure aging. In order to accelerate the development of therapies to get aging under full medical control, the Forever Healthy Foundation directly supports cutting edge research aimed at the molecular and cellular repair of damage caused by the aging process. "We are extremely proud to be supporting this project and partnering with the Buck. With this and other collaborations we are planning, SRF looks forward to expanding our contribution to the advancement of medical research on pathologies associated with human aging."

Link: http://www.sens.org/outreach/press-releases/srf-and-buck-institute-to-collaborate-on-neurodegeneration

A Cross-Section of Recent Work in the Aging Research Community

A recently published report from last year's Biomedical Innovation for Healthy Longevity conference, held in Russia, serves as a sampling of ongoing work in the field of aging research; a wide range of views on theories of aging are represented. One thing that strikes me from a review of the topics is that few of the people involved are working on anything related to rejuvenation, or, setting aside the much-needed consideration of biomarkers of biological age, any other projects with near term practical applications likely to significantly extend life. For the most part this is a field concerned with investigation, development of drugs that produce small effects on aging, and little else. The primary thrust is to map the cellular biochemistry of aging in as great a detail as possible, one small step at a time, with a sideline in finding drug candidates that might somewhat alter that biochemistry. Insofar as fundamental research goes, this is indeed the goal of science as a whole, to achieve greater understanding of the complex systems of the natural world. It has been argued that this is not the right focus for those groups that aim for the more rapid production of effective therapies capable of greatly extending healthy life spans, however, given the present state of knowledge.

Regular readers will know the argument already. The research community knows enough about the root causes of aging to strike out and build effective therapies even if the full details of the biochemistry involved have yet to be mapped out. Take senescent cells, for example. Their involvement as a cause of aging has become increasingly clear over the past thirty years of investigation. It is now demonstrated that removing senescent cells reliably reverses aspects of aging and extends life in mice. Yet at the level of cell mechanisms and signals, there lies ahead at least another decade or two of further work to catalog all of the relationships and interactions responsible for the harms caused by these cells. Scientists will undertake that work, of course. But it should not be the focus for clinical research, given that the basis for an effective therapy exists today in the form of destroying these cells, an approach that cuts through the unknown mechanisms, fixing them just as effectively as it fixes the problems that are known and understood.

Cellular senescence is but one example of many. Researchers in general do a very poor job of identifying and addressing root causes in aging, however. Because they are primarily engaged in mapping and discovery, they tend to focus on late stages of aging, working backwards from a state of dysfunction step by step and protein by protein in long and complex chains of cause and consequence. When they propose therapies as a result of their findings, these therapies necessarily take the form of tinkering with the already malfunctioning operation of metabolism - altering the downstream consequences of fundamental damage, rather than repairing that damage. The outcomes are inevitably marginal. Trying to keep a damaged engine effective by changing the oil or running it hot, while failing to replace the worn and damaged parts that are the cause of the issue, is a futile endeavor. This is just as true of our biology. So while there are many interesting items in the full report, just a few of which are quoted below, remember that interesting doesn't necessarily mean useful enough to justify the expenditure of a great deal of effort and funding.

A review of the biomedical innovations for healthy longevity

Blanka Rogina (University of Connecticut Health) "Indy reduction maintains fly health and homeostasis". Indy (I'm not dead yet) encodes the fly homologue of a mammalian transporter of the Krebs cycle intermediates. Reduced Indy gene activity has beneficial effects on energy balance in mice, worms and flies, and worm and fly longevity. In flies, longevity extension is not associated with negative effects on fertility, mobility or metabolic rate. Others and we show that Indy reduction extends longevity by mechanism similar to calorie restriction (CR).

Vladimir Skulachev (Moscow State University) in his lecture "Naked Mole Rats and Humans: Highly Social Creatures Prolonging Youth by Delay of Ontogenesis (Neoteny)" considered some physiological mechanisms responsible for longevity of eusocial mammals, i.e. a rodent (naked mole rat) and a primate (human). It is concluded that both naked mole rat and human are no more affected by dynamic natural selection due to specific organization of the socium (naked mole rat) and substitution of fast technical progress for slow biological evolution (human). Since aging is supposed to be a program stimulating evaluability by increasing pressure of natural selection upon an individual, such a program became a harmful atavism for naked mole rat and human. This is apparently why aging as a reason for death is very rare in naked mole rats younger than 30 years and humans younger than 55 years. Such an effect is achieved, at least partially, by prolongation of youth (neoteny). The numerous facts are described indicating that The Master Biological Clock responsible for timing of ontogenesis is retarded both in naked mole rat and in human. In these species, numerous traits of youth do not disappear (or disappear enormously slowly) with age.

David Gems (University College London) spoke on "The origins of senescent pathology in C. elegans". The biological mechanisms at the heart of the aging process are a long-standing mystery. An influential theory has it that aging is the result of an accumulation of molecular damage, caused in particular by reactive oxygen species (ROS) produced by mitochondria. This theory also predicts that processes that protect against oxidative damage (involving detoxification, repair and turnover) protect against aging and increase lifespan. However, recent tests of the oxidative damage theory, some using the short-lived nematode worm C. elegans, have often failed to support the theory. This motivates consideration of alternative models. One new theory proposes that aging is caused by the non-adaptive running on in later life of developmental and reproductive programmes. Such quasi-programmes (i.e. that are genetically programmed but non-adaptive) give rise to hyperfunction, i.e. functional excess due to late-life gene action, leading via dysplasia to the age-related pathologies that cause the late-life increase in mortality. Here we assess whether the hyperfunction theory is at all consistent with what is known about C. elegans aging, and conclude that it is.

S. Michal Jazwinski (Tulane University Health Sciences Center) presented "Metabolic and Genetic Markers of Biological Age". Biological and chronological age are not the same, as individuals depart in health from the average. Taking a systems approach, we developed an objective measure of healthy aging, a frailty index (FI34) composed of 34 health and function variables. FI34 is a much better predictor of mortality than is chronological age; therefore, it directly reflects biological age. It increases exponentially with chronological age, but it does so more slowly for offspring of long-lived parents. FI34 is also heritable. Thus, it can be used in genetic analyses. The patterns of aging described by the variables in FI34 are very different for offspring of long-lived and short-lived parents. We have examined the association of the components of energy metabolism with FI34 in the oldest-old. Surprisingly, there is a positive association of FI34 with resting metabolic rate (RMR). This points to the rising cost of maintenance of integrated body function with declining health during aging.

Daniel Belsky (Duke University) presented "Quantification of biological aging in young adults". Population aging threatens to bring a tidal wave of disease and disability. Strategies to prevent or treat individual diseases will be inadequate to contain costs and preserve economic productivity; interventions that address the root cause of multiple diseases simultaneously are needed. We studied aging in 954 young humans, the Dunedin Study birth cohort. To quantify biological aging in these individuals, we tracked multiple biomarkers across three time points spanning their 20s and 30s. We devised a longitudinal measure that quantifies the pace of coordinated physiological deterioration across multiple organ systems. This measure, the "Pace of Aging," showed substantial variation in young, healthy adults who had not yet developed age-related disease. Young adults with faster Pace of Aging were, by midlife, less physically able, showed cognitive decline and brain aging, self- reported worse health, and looked older.

Tamas Fülöp (University of Sherbrooke) presented "Are there any reliable biomarkers for immunosenescence?". Aging is accompanied by many physiological changes including those related to the changes in the immune system. These changes are called immunosenescence which is accompanied by the inflammaging phenomenon. Many biomarkers have been proposed to describe these age-associated changes in the immune system. One of the most consistent is the chronic Cytomegalovirus infection. Most of the elderly are affected in developed countries which about 70% and in developing countries about 100% at the age of 80. Despite the numerous studies there is no consensus which role the recurrent CMV infections play in the alterations of the immune system namely in the inflammaging process and in the more consistent phenotypic alterations of T cells.

Alexander Kulminski (Duke University) reported "Can age-specific genetic effects be relevant to biological age?". Living organisms are getting older and eventually die at a certain age. The actual time an organism has been alive refers to chronological age (CA). However, not all organisms die at the same chronological age even if they are of the same species. The idea of biological age (BA) is that the differences in lifespan of these organisms can be due to an internal clock. For humans, BA refers to how old that human seems. A problem, however, is how to quantify BA. A promising approach could be to express BA in terms of measurable phenotypes such as biomarkers. As phenotypes, biomarkers represent endpoints of a cooperative work of genes in an organism. Accordingly, BA could readily have a genetic origin. Does it necessarily imply that there should be specific genes regulating BA? The answer is not straightforward.

Ksenia Lezhnina and colleagues presented "Signaling pathways signature of sarcopenia identified by iPANDA algorithm." Sarcopenia is a losing muscle mass and function with aging. Decreased strength and power of muscle function may contribute to higher risks of accidents among older people and affects quality of life. Until recently sarcopenia was not even considered as a pathological condition and as a consequence clinical definition and diagnostic criteria is poorly developed. Mechanisms underlying sarcopenia are extensively investigated but still not fully understood. In order to study this we compare transcriptomic profiles of muscle tissues from young and old people, both women and men. We assume that aging process starts from the fourth decade of life. We apply a new algorithm in silico Pathway Activation Network Decomposition Analysis (iPANDA) to transcriptomic data to find signaling pathway signatures of aging in muscle tissues. Common pathway signatures can be considered as a target for development of new approaches for sarcopenia treatment.

Matt Kaeberlein (University of Washington) presented "Effects of transient mid-life rapamycin treatment on lifespan and healthspan". The FDA approved drug rapamycin increases lifespan and improves measures of healthspan in rodents. Nevertheless, important questions exist regarding the translational potential of rapamycin and other mTOR inhibitors for human aging, and the optimal dose, duration, and mechanisms of action remain to be determined. Here I will report on studies examining the effects of short-term treatment with rapamycin in middle-aged mice and dogs. We find that transient treatment with rapamycin is sufficient to increase life expectancy by more than 50% and improve measures of healthspan in middle-aged mice. This transient treatment is also associated with a remodelling of the gut microbiome, including dramatically increased prevalence of segmented filamentous bacteria in the small intestine, along with a dramatic shift in the cancer spectrum in female mice. In dogs, we have defined a dose of rapamycin that is well tolerated, and initial results are consistent with improvements in age-associated cardiac function similar to those observed in rapamycin-treated mice. These data suggest that a transient treatment with rapamycin may yield robust health benefits in mice, dogs, and perhaps humans.

Maxim Skulachev (Mosсow State University) presented "Development of mitochondrially-targeted geroprotectors: from the molecular design to clinical trials and marketing strategy". Research and development of geroprotectors is always challenging when the project passes from theoretical and laboratory work to routine drug development (preclinical and clinical trials and medical authority approvals). In this talk, we present an example of an anti-ageing RnD project aimed on creation of geroprotector drugs on the basis of rechargeable mitochonrially-targeted antioxidants. Our strategy is to get the potential geroprotector approved as a drug against a certain age-related disease, and then to expand the list of indications for this pharmaceutical to other traits of ageing. We synthesized a series of novel organic compounds, derivatives of plastoquinone. Our first pharmaceutical was designed for local administration (in the form of eye-drops) to speed up the process of clinical development and to get the clinical data faster. At the current stage of the project our first drug Visomitin (Rx eye drops with antioxidant SkQ1 helping in such age-related diseases as dry eye syndrome and cataract) has been approved and marketed in Russia and successfully passed phase II clinical trials in US. Systemic oral form of SkQ1 has entered clinical trials in Russia and completed preclinical program in US and Canada. We consider our project to be a valuable attempt to slow down human aging by a mitochondrial approach.

PORCN Inhibition Spurs Greater Heart Tissue Regeneration

Researchers here report on a fortuitous discovery made while searching for potential cancer therapeutics based on the suppression of mechanisms essential to growth and cellular replication, such as the Wnt signaling pathway. To the surprise of the research team, inhibition of the protein encoded by the porcupine (PORCN) gene, required for Wnt signaling, was found to spur greater heart tissue regeneration.

An anticancer agent in development promotes regeneration of damaged heart muscle - an unexpected research finding that may help prevent congestive heart failure in the future. Many parts of the body, such as blood cells and the lining of the gut, continuously renew throughout life. Others, such as the heart, do not. Because of the heart's inability to repair itself, damage caused by a heart attack causes permanent scarring that frequently results in serious weakening of the heart, known as heart failure. Researchers have worked to develop a cancer drug targeting Wnt signaling molecules. These molecules are crucial for tissue regeneration, but also frequently contribute to cancer. Essential to the production of Wnt proteins in humans is the porcupine (Porcn) enzyme, so-named because fruit fly embryos lacking this gene resemble a porcupine. In testing the porcupine inhibitor researchers developed, they noted a curiosity.

"We saw many predictable adverse effects - in bone and hair, for example - but one surprise was that the number of dividing cardiomyocytes (heart muscle cells) was slightly increased. In addition to the intense interest in porcupine inhibitors as anticancer agents, this research shows that such agents could be useful in regenerative medicine." Based on their initial results, the researchers induced heart attacks in mice and then treated them with a porcupine inhibitor. Their hearts' ability to pump blood improved by nearly twofold compared to untreated animals. Importantly, in addition to the improved pumping ability of hearts in the mice, the researchers noticed a reduction in fibrosis, or scarring in the hearts. Collagen-laden scarring that occurs following a heart attack can cause the heart to inappropriately increase in size, and lead to heart failure. Preliminary experiments indicate that the porcupine inhibitor would only need to be used for a short time following a heart attack, suggesting that the unpleasant side effects typically caused by cancer drugs might be avoided. "We hope to advance a Porcn inhibitor into clinical testing as a regenerative agent for heart disease within the next year."

Link: http://www.utsouthwestern.edu/newsroom/news-releases/year-2017/feb/heart-regeneration-lum.html

The Moderate Drinking Effect on Health may be Explained by Wealth and Status

The scientific mapping of health and longevity variations in humans is largely a matter of mining demographic data for correlations, with little opportunity to directly determine causation over the decades needed for such studies. One particularly tightly-bound web of correlations involves intelligence, education, social status, wealth, and life expectancy. All influence one another, and a definitive determination of the root causes of these correlations remains a work in progress, and will probably continue to be so for some time yet.

Evidence for unexpected relationships exists, such as physical robustness being genetically linked to intelligence, as well as for the expected capacity of greater wealth to improve health and life expectancy. Analysis is certainly a complex business, and spirals out into many other possible correlations in behavior and circumstances. One of the better known lifestyle choices that touches on this area is moderate alcohol consumption, associated as it is with reduced mortality. It was always to some degree suspected that this association only exists because moderate drinking is in and of itself correlated with wealth and status, rather than being driven by any physical mechanism. One study to provide evidence in that direction is not enough on its own, of course, but it is something to take into account alongside others.

To assess whether a relationship between alcohol use and health exists for older adults before and after controlling for proxy and full indicators of socioeconomic status, we undertook a secondary analysis of data from 2,908 participants in the New Zealand Longitudinal Study of Ageing who completed measures of alcohol use, health, socioeconomic status proxies (income, education) and socioeconomic status itself. Sample mean age was 65, 52% were female, more than 80% were drinkers, and more than 75% had educational qualifications.

Moderate drinkers had better health and socioeconomic status than heavier or nondrinkers. The positive influence of moderate alcohol consumption on health was observed for men and women when controlling for socioeconomic status proxies, but was substantially reduced in women and completely disappeared for men when controlling for full socioeconomic status. socioeconomic status plays a key role in presumed "heath benefits" of moderate alcohol consumption for older adults. It accounts for any alcohol-health relationship in a sample of men of whom 45% consume at least one drink daily, and substantially attenuates the association between alcohol and health in a sample of women who are not frequent drinkers. Prior research may have missed the influence of socioeconomic status on this alcohol-health relationship due to the use of incomplete socioeconomic status measures.

Link: https://doi.org/10.1093/geronb/gbw152

Biologically Modified Justice

Long time readers no doubt already know that I'm not much in favor of social justice as it is practiced and advocated these days. Just like Marxist communism or other forms of idealized socialism, the concepts sound great when presented in the philosophical abstract, detached from the process of actually running an implementation through the messy reality of human nature and human society. Unfortunately, in practice you wind up with things like the millions of deaths in the old Soviet Union, the sad state of Venezuela today, and in the wealthier and more successful parts of world, a substantial fraction of society who would read Harrison Bergeron as something other than satire. Charity is a wonderful thing. Forcing other people into your choice of charity with the threat of imprisonment and violence, less so. Similarly for dragging down the best and the brightest and the most entrepreneurial, those who are working to build the better tomorrow. If you press them into doing nothing more than supporting mediocrity and paying for the consequences of failure, then the future will be one of far more mediocrity and failure, not progress.

So that said, today I thought I'd point out Biologically Modified Justice, a book written by an academic who is very much in favor of both social justice and bringing an end to aging and age-related disease. I linked to his blog here and there back when he was writing regularly on the topic of longevity science; it was interesting to observe someone within a community traditionally hostile towards life extension - and to technological progress in general, for that matter - reconciling the urge to personal health and longevity with a doctrine that proclaims any such urge for self-improvement as somewhere between selfish and evil. A widespread view among many of the social justice community, insofar as we can put a single label on a very broad collection of diverse viewpoints, is that progress must start by raising up the weakest and poorest. Attempts to build new technologies always benefit the wealthy and the influential first of all, and are thus either viewed with suspicion or vetoed outright, even given the history of countless initially expensive technologies that rapidly became available for the masses at a low cost. Those who throw stones at the altar of inequality wish for a society more level, and often at any cost to progress.

Fortunately there are more sensible voices, such as the author of the book linked below, though I fear they often have little influence over what passes for the mainstream of thinking regarding social justice, and sensible or not, even their more polite views are still footsteps on the same road that led to the Soviet Union and Venezuela. Human nature and enforced equality are just not compatible housemates. Still, I think most of you would find Biologically Modified Justice an interesting read, regardless of your leanings on the optimal organization of human society. As the biotechnologies of human rejuvenation move closer to widespread availability in the clinic, we are going to see many new voices in favor of rejuvenation arise in communities that are at this time generally hostile towards progress and enhanced longevity. There will be numerous attempts to synthesize the urge to live longer, and the advent of the means to do so, with philosophies that presently reject that goal. These are interesting times.

Biologically Modified Justice

Theories of distributive justice tend to focus on the issue of what constitutes a fair division of 'external' goods and opportunities; things like wealth and income, opportunities for education and basic liberties and rights. However, rapid advances in the biomedical sciences have ushered in a new era, one where the 'genetic lottery of life' can be directly influenced by humans in ways that would have been considered science fiction only a few decades ago. How should theories of justice be modified to take seriously the prospect of new biotechnologies, especially given the health challenges posed by global aging? Biologically Modified Justice addresses a host of topics, ranging from gene therapy and preimplantation genetic diagnosis, to an 'anti-aging' intervention and the creation and evolution of patriarchy. This book aims to foster the interdisciplinary dialogue needed to ensure we think rationally and cogently about science and science policy in the twenty-first century.

The idea that we could directly alter the biology of a person via genetic intervention, or develop an 'anti-aging drug', or utilize genetic tests for screening genetic diseases would have been considered pure science fiction just a few decades ago. And yet all of these prospects either have become, or might soon be, a reality. And as science progresses we may be able to promote the health prospects of the current generation (and all future generations) by improving our biological capacity to fend off infectious and chronic diseases. I began working on this book in the year 2000. That was the same year two rival teams were racing to sequence the human genome. As I began to follow the field of human genetics, and to think about the importance of science more generally, I realized that there was very little written by political theorists on these topics. Over the years the neglect of science, especially the biomedical sicences, began to trouble me more and more. It troubled me both as a teacher and as a scholar.

As a teacher I found it disturbing that my students learned about topics such as justice, freedom, and equality but did not really learn about the important role science and innovation play in helping humanity create more fair and humane societies. Current debates about distributive justice often give students the impression that justice only involves the distribution of wealth and income, or giving priority to basic liberties like free speech. But government decisions to stifle or promote basic and applied scientific research can also have profound impacts on our life prospects. What constitutes 'well-ordered' science? Would we know unjust science policies when we see them? Neglecting these issues comes with great peril, as many of the most pressing challenges humanity faces this century will require new knowledge and innovation.

Rather than simply extending existing theories of justice to encompass the new developments of the genetic revolution, I came to the conclusion that the genetic revolution that was unfolding around us required political theorists to re-think the basic premises of what the demands of justice are, as well as what we wanted or expected from our theories of justice. Can insights from evolutionary biology and genetics help the political theorist develop emancipatory knowledge about the kind of society, institutions, and culture we should aspire to realize in the world today? I decided to write this book because I believe the answer to this question is an emphatic 'Yes!'

Short Term Damage Done by Amyloid in the Brain Appears to be Reversible

This compact study suggests that the damage caused to neurons by the presence of β-amyloid in the short term can largely repair itself if the amyloid is removed. This is one of a number of lines of evidence to indicate that targeted clearance of amyloid should produce reversal of symptoms in Alzheimer's disease in at least the earlier stages, before there is widespread cell death, rather than just a halt to the progression of the condition.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized clinically by memory loss and cognitive decline. Its major pathological hallmarks are extracellular senile plaques and intracellular neurofibrillary tangles, which are composed of amyloid β-protein (Aβ) and phosphorylated tau (p-tau) protein, respectively. A central role of Aβ in the molecular pathology of AD has been established. Aβ is generated by sequential cleavages of amyloid precursor protein (APP) by β-site APP cleaving enzyme 1 (BACE1) and γ-secretase. Under pathological conditions, Aβ self-aggregates to form Aβ oligomers, which likely induce abnormalities of tau and cause cellular stress responses, including caspase activation and disturbances of synaptic structure and plasticity. Thus, Aβ oligomers are considered to be an initiator of AD pathology.

The mechanisms by which Aβ oligomers induce neurotoxicity, critical issues from a therapeutic standpoint, remain to be elucidated, although several hypotheses have been suggested. The major theory is that extracellular Aβ oligomers interact with certain cell surface receptors to cause aberrant signal transduction. Alternatively, it has been suggested that extracellular Aβ oligomers disrupt the cell membrane directly or intracellular Aβ oligomers elicit neurotoxicity. Although a link between Aβ oligomers and tau has been established, signaling pathways linking the two remain elusive. It also remains to be clarified whether the neurotoxicity of Aβ oligomers is reversible and abates upon their removal. We previously established a primary neuron culture model in which Aβ oligomers trigger apparent neurotoxicity with relatively modest neuronal death. In the current study, we took advantage of this system to investigate the reversibility of Aβ oligomers-associated neurotoxicity, characterized by caspase activation and tau abnormalities. Here, we present evidence that the neurotoxicity of Aβ oligomers is reversible in primary neurons.

Our data showed that Aβ-O induces activation of caspase-3 and eIF2α, and abnormal phosphorylation and cleavage of tau. These abnormal alternations have been reported to be present in AD brains, suggesting that our model reflects the characteristic features of AD pathology. Our study also provides evidence of a direct link between Aβ oligomers and tau abnormalities, in accord with previous studies. To evaluate whether Aβ oligomer neurotoxicity is a reversible or irreversible process, we used an experimental paradigm in which neurons exposed to Aβ oligomers for 2 days were further treated with Aβ oligomers for 2 additional days or were deprived of Aβ oligomers for this same culture period. We then compared control and Aβ-oligomer-treated neurons on day 2, and control, Aβ-oligomer-treated and Aβ-oligomer-deprived neurons on day 4. We first focused on caspase-3 and eIF2α, both of which are thought to be important in mediating AD neurodegenerative processes. We found that the levels of cleaved caspase-3 and p-eIF2α in Aβ-oligomer-deprived neurons were much lower on day 4 than those in neurons continuously treated with Aβ oligomers, and were similar to those in controls. These findings suggest that neurons can recover following Aβ oligomer removal, even after neuronal injury responses to Aβ oligomers have already progressed, supporting the view that treatments targeting Aβ oligomers have significant therapeutic potential for AD.

Link: https://dx.doi.org/10.1186/s13041-016-0284-5

An Interview with Irina and Michael Conboy on Blood Factors in Aging

Here is a lengthy interview with researchers Irina and Michael Conboy on their work with parabiosis. This involves joining the circulatory systems of an old and a young mouse, and studies have shown that this reverses some measures of aging in the old mouse. Researchers have so far largely focused on the possible effects of signal molecules present in young blood, but the most recent work from the Conboy lab provides fairly compelling evidence to suggest that the more interesting benefits are instead produced by a dilution of harmful signals in old blood. This is reinforced by the possible identification of one of those signals by another research group. In the bigger picture, this means that initiatives involving blood transfusions are probably going to fail, and would explain why transfusions in mice didn't produce noteworthy outcomes. One alternative approach suggested by this new research is plasmapheresis, a class of existing therapy in which blood plasma is replaced in volume, and which would hopefully also dilute harmful signals in the process.

Dan Pardi: In my conversation with Aubrey de Grey, he was optimistic of stem cells being one area in which we can effect aging itself. If we have these stem cells that regenerate and then can become new tissue, what does happen with aging to stem cells?

Irina Conboy: What we believe and we found is that, interestingly, stem cells remain relatively young in a person who is 80, 85 years old. You are like a mosaic of cells. Many of your cells are old, decrepit. They have damaged DNA and short telomeres and what not. But stem cells are actually pretty healthy, and young, and functional. They are inhibited. They are pretty much blocked by their surrounding tissue, called the niche. That niche blocks them from performing any work. The cells that we know work just like keep sleeping and do not repair the tissue. Then, because of that, when there is tissue damage and stem cells are sleeping, they are not activated. Then the damage is not regenerated. Instead you have fibrosis. It's like your plan B. You now make fibrous tissue, and depose fat tissue to replace the damage. Then gradually the time, you just turn into this big scar and big fat blob. Then if you figure that there are proved ways to reawaken stem cells then 70 year old, 80 year old person will start regenerating. All of the organs as if they are 20 year old. Gradually, not only you prevent all these bad diseases to happen but perhaps start getting even younger.

Dan Pardi: One publication that got a lot of attention is one where you did this parabiosis experiment where you had blood exchanged from an old rat to a young rat. Tell us a little bit about that one.

Irina Conboy: In this experiment we found that old animal becomes much younger, with respect to muscle degeneration, formation of new neurons in the brain. Also, liver regeneration. All of these molecules which were responsible for making animal younger were also rejuvenated. It was not just a fluke. There was also fundamental mechanism of how they became younger. The young animals suffered from this connection. Became older, particularly in liver and in brain. From that time on, people kind of became obsessed with the stories about vampires and that young blood holds the secret to health, and youth, and so forth. It was really strange to me. It was surprising that that was such a simplistic interpretation of our findings. Which we did not intend our findings to be interpreted like that. Also, that how much, I guess, interest it got. It really absorbed all of the funding in the area. As a result there was not enough funding to do any alternative work, which in my opinion was the most important work to do. The main secret there is that mice share more than blood when you staple them. When they live together for like an entire month, then old mouse now has access to young heart. The blood pressure becomes better. Young lungs, so now you have better oxygenation of blood. Red blood cells now are more oxygenated. Also, you have young red blood cells going into an old animal. Also, you have young liver. You have much better metabolism. You have young immune system. You have much less inflammation. It is not, you know, those secret proteins in blood. It is simple things like how much oxygen does your brain get. That was completely overlooked.

Dan Pardi: What did you think was going on? What was your next experiment that took it a step further to identify really what was going on?

Michael Conboy: At the time we also would take cells and grow them in culture. Usually when you do that you add some amount of serum to that. That's the liquid fraction of blood. You spin out the cells. If you grow the cells in young serum, they grow very well. If you grow them in old serum, they grow poorly. What was interesting was if we mixed young serum and old serum together, the cells grew poorly. That indicated that there was something that was in the old serum that was suppressing the growth and was also dominate over whatever was in young serum. That got us thinking that what was growing on in parabiosis must be more along on the lines of the young animals filtering some old, inhibitory stuff out of the old mouse. Maybe more than it's adding young positive factors to the mix. That got Irina thinking that there's got to be something that circulates, that's inhibitory, and what could it be?

Irina Conboy: Then, we were thinking about the clear experiment. A proof of principal which we will once and for all discriminate between whether young blood is good or whether we need to remove old blood inhibitors. That's how we switched to the blood exchange. Which is much more difficult to set up than parabiosis. It is much better experimental set up to answer many questions. In blood exchange, in fact, we do exchange only blood. There are small catheters which are inserted into mouse veins. You can imagine, mice are very little, how tiny their veins are. You need to be very, very skilled to be able to catheterize mouse veins. Then there is a pump that pretty much mixes the blood from young mouse with an old mouse to equilibrium. Which is identical to parabiosis. There is no loss of blood. There is no gain of blood. They are mixed in exactly the same way. That happens in one day. Then mice are not living together for one month anymore. They do not share organs. You exchange their blood. Then very quickly you can study what happens with their organs and tissues. Most surprising findings that you have from this experiment is that, yes, blood exchange without any organ sharing or adaptation does have effect on youth and aging. The effect is almost instantaneous. It implies completely different set of mechanisms as compared to when mice are sutured and running together.

Dan Pardi: For humans would be like a dialysis situation. Now you have to just figure out, how frequently? How much needs to be removed and put back in?

Irina Conboy: We have clinical trials under development with our colleague Professor Dobri Kiprov from San Francisco Blood Apheresis Clinic. Who is doing blood exchange in people for 35 years. He contacted us because of reading our papers. Make him interested in can this be repositioned. Repositioning is when you already have FDA approved procedure and your clinical trial therefore are much more advanced. You just see if the same or slightly modified protocol can be used. We do plan to study in those clinical trials how much younger do people become? Do they become younger in their epigenetics for example? Do they become younger in their lack of predisposition to cancer? There are many, many parameters that we can study. How much improvement can we expect from our process or approach where we take person's blood and it goes through the plasmapheresis machine in the approved process?

Link: http://blog.dansplan.com/can-we-reverse-aging-with-young-blood/

Building a Better Cellular Senescence Assay: LongeCity Puts Forward a $3000 Matching Challenge for the CellAge Fundraiser

CellAge is seeking philanthropic funding to build a better class of assay for senescent cell presence in tissues, a technology they plan to make freely available to academic researchers if successful in their efforts. Present assays for cellular senescence are well-established, some little changed for two decades, but are by now somewhat clunky and behind the times. They suffice for research and development, but are not a good basis for the coming future of low-cost, reliable clinical tests. An increase in the numbers of senescent cells throughout the body is one of the root causes of degenerative aging. Given the broad influence of cellular senescence in aging and many age-related conditions, with new evidence for this influence arriving every month these days, I would think that everyone should be assayed as a matter of course, a part of any sensible health checkup. Unfortunately, that would be hard to do today at a reasonable cost, even assuming you could find a company offering the service. The need for better assays will only increase as senolytic therapies of various sorts become available via medical tourism, and later in clinics in the US and Europe. If underging a treatment that removes senescent cells, then one would certainly want a reliable method of proving that it worked.

I have been speaking with the CellAge principals of late to work on other possibilities for funding, and help them to make some potentially useful connections within the community. That effort moves along at its own slow pace behind the scenes; it always takes a while to find out whether or not matters can be lined up to a useful conclusion, and then there is the separate undertaking of actually moving ahead to make that conclusion happen. Meanwhile, every additional helping hand makes things that much easier. Thus I am most pleased to note that the LongeCity community has put up a $3000 matching fund to help spur donations to the present crowdfunding initiative. They have sensibly made this a part of their existing program for funding discrete scientific projects, and picked out one portion of the necessary work at CellAge that will produce a useful outcome for the research community even standing alone. Good for them.

CellAge fundraiser support

LongeCity.Org has decided to support the current CellAge Fundraiser initiative beyond its standard support for certified 'star-rated' community fundraiser through an extension of its affiliate lab programme. To this end we have identified a specific small 'sub goal' within the first work project of the CellAge programme to get behind: The first 'work project' of the CellAge fundraiser is to design candidate synthetic promoters which would be able to accurately detect senescent cells. One of the very first scientific steps is to analyse transcription profiles of senescent cells. The team plans to cover different senescence states, in cells from different tissues and at different stage of senescence. The LongeCity target fund is raised in support of achieving one variant of this initial sub-goal: to ascertain the unique RNA profile of induced senescence in human fibroblasts.

By clearly defining the boundaries of this sub-goal we can be assured that contributions made towards it are directly impactful. In fact, even if the whole project should need some more time to develop, just this sub-goal alone might be a valuable contribution to anti-aging research. At the same time all the data generated in the sub-goal is directly integral to the larger whole of the project. LongeCity has committed to match $3000 worth of donations specifically in support of this sub-goal. Priority will be given to donations made through the LongeCity site, prior to February 18th.

Longecity Fund Match Announced For CellAge Campaign

Hello, dear friends! So far we have raised over 14,000 dollars for the CellAge campaign! There are 22 days left before the campaign ends, and it is time to make another push towards the victory line. Also we have an exciting announcement: the CellAge project is now endorsed by LongeCity, one of the oldest international pro-longevity organizations. Their forum represents an exclusive education platform that has helped thousands of people learn about the endeavor to bring aging processes under medical control, remain informed about the latest breakthroughs, and develop their own strategy of health maintenance.

The LongeCity community has certified this important research project to target and remove harmful senescent cells, and is contributing $800 right away. They are also running an internal fund match: anything donated at LongeCity before February, 18 will be doubled up to $3000, and then the whole amount will be sent to support CellAge campaign on Lifespan.io. Donations made this way will still be eligible for corresponding Lifespan.io rewards, so don't hold back! You are very welcome to contribute, and please remember that every dollar you donate at LongeCity becomes two - and the project will receive a nice push to get us to our goal: control over senescent cells!

Investigating the Details of Slowed Immune Aging via Calorie Restriction

The practice of calorie restriction slows all aspects of aging, and produces sweeping changes in the operation of cellular metabolism. This makes for a great deal of work in order to understand how and why it generates beneficial effects. Even separating out root causes from downstream consequences is a slow and expensive challenge for the research community, as understanding calorie restriction must proceed hand in hand with understanding the fine details of cellular biochemistry as a whole - an enormous project that is nowhere near complete. You might look back at the past decade of work on sirtuins for an example of one small slice of the bigger picture, still not complete, and so far undertaken at a cost of hundreds of millions of dollars. In the open access paper noted here, the focus is on one small part of the slowing of immune decline with aging as a result of calorie restriction. As is often the case, the research generates more questions than answers:

In mice, calorie restriction enhances responses to vaccination, reduces the incidence of spontaneous malignancies, and, in some inbred strains, extends lifespan. Specifically, restriction of the calorie intake of C57BL/6J mice by 40% compared to that of mice fed ad libitum (AL), extends median lifespan by more than 35% (i.e., from around 24 months to around 32 months) whereas the lifespan of DBA/2J mice is not extended by calorie restriction. This differential response to calorie restriction may be linked to lower basal metabolic rate, lower oxygen consumption, higher oxidative stress, higher body fat, and continued weight gain throughout adult life in C57BL/6 mice compared to DBA/2 mice fed ad libitum (AL) although differential effects on nutrient sensing cannot be ruled out.

Importantly, age-associated changes in the adaptive immune system - typified by thymic involution, reduced production of naïve T cells, reduced T cell proliferation, reduced cytotoxic T lymphocyte activity, and progressive skewing of the T cell pool toward more mature, memory phenotypes with increasing age - are attenuated by calorie restriction. In mice and in non-human primates, calorie restriction conserves T cell function and repertoire and promotes production and/or maintenance of naïve T cells. The effects of aging and calorie restriction on the innate immune system are, however, much less well studied. Altered function of innate cell lineages of aged individuals has been linked to defective immune regulation and chronic inflammation. In particular, age-associated dysfunction of natural killer (NK) cells has been reported in mice and humans. Progressive narrowing of the NK cell functional repertoire with increasing age may contribute to immune senescence.

NK cells in aged mice appear functionally impaired. Calorie restriction seems to mimic the effects of aging on murine NK cells, with 40% calorie restriction leading to reduced numbers of peripheral NK cells and decreased proportions of the most differentiated NK cell subset in 6-month-old C57BL/6 mice. One study also suggested that CR mice are more susceptible to infection, with lower NK cell activity, again mimicking the effects of aging, although the causal relationship between NK cell function and outcome of infection remains to be tested. Despite evidence that calorie-restriction appears to mimic the effects of aging in murine NK cells, calorie restriction enhances healthy life span in C57BL/6 mice suggesting that age-related changes in murine NK cells may have evolved to preserve innate immune function, and thus resilience in the face of infection, in adult life and thus that there is an underlying unappreciated interaction between age and calorie intake. In an attempt to reveal this interaction, we have - for the first time - analyzed the effects of calorie restriction on NK cell and T cell phenotype and function throughout the life course in C57BL/6J and DBA/2J mice.

To our surprise, the effect of calorie restriction on the NK cell population was to exaggerate, rather than attenuate, the normal age-associated changes in NK cell phenotype and function. Our data suggest that calorie restriction attenuates age-associated effects in T cells but, conversely, accelerates the effects of aging in NK cells, and that the effect of calorie restriction is much more marked in C57BL/6 mice than in DBA/2 mice. The conventional wisdom is that aging is associated with the accumulation of mature, terminally differentiated immune cells with restricted functional capacity, leading to loss of immune integrity, while calorie restriction is believed to preserve immune function, possibly by maintaining the pool of immune cell precursors or stem cells. However, very few studies have looked at the effect of aging or calorie restriction on NK cell function. Overall, calorie restriction had at least as big an effect as age on NK cell and T cell phenotype, and, where aging per se affected immune cells, these effects could be almost totally reversed (in the case of T cells) or were markedly exaggerated (in the case of NK cells) by calorie restriction. The very different effects of age and calorie restriction on T cell and NK cell differentiation and maturation suggest that, despite their many shared features, the underlying response of T cells and NK cells to increasing age and nutritional constraints is, mechanistically, very different.

Similarly, although the immunological effects of aging are very similar in C57BL/6 and DBA/2 mice, the effect of calorie restriction is much less obvious in DBA/2 mice than in C57BL/6 mice. This suggests, but does not prove, that the lack of benefit (in terms of longevity) from calorie restriction in DBA/2 mice may be associated in some way with the failure of the immune system to respond to the change in diet. As discussed above, an intriguing finding from this study is that calorie restriction potentiates age-associated changes in NK cell phenotype and function while simultaneously ameliorating age-associated changes in T cells. However, given the different age-related trajectories of T cell and NK cell populations in control animals, the overall effect of calorie restriction is to maintain larger populations of immature or less differentiated T cells and NK cells. Among NK cells, the maintenance of a less mature phenotype is reflected functionally with increased proliferative responses to cytokine stimulation. This is in partial agreement with evidence from mice and humans, which indicates that less differentiated NK cells express high levels of cytokine receptors and respond strongly to cytokine-mediated signals.

Overall, the effect of calorie restriction is that 22-month-old CR mice retain the immune cell phenotype of 6-month-old conventionally reared mice - the underlying basis for this is not entirely clear. Retention of an immature T cell and NK cell phenotypes in aged, CR mice may result from continuing production of new, immature cells; from accelerated turnover and apoptosis of mature cells; from extension of the life span of individual cells such that they take much longer to mature; or from a combination of any or all of these processes. Our data suggest that calorie restriction may preserve immune function in later life but this is only likely to be beneficial if improved immune function can be achieved whilst still maintaining the energy reserves required to fight infection. More research is required to better understand the interaction between nutritional status, immune function, and healthy aging, in relevant animal models and in humans.

Link: https://doi.org/10.3389/fimmu.2016.00667

More Results for the Use of Immune System Reconstruction to Treat Autoimmunity

More evidence is accumulating to show that autoimmune diseases might be effectively treated by destroying the existing population of immune cells and then recreating them: the problem lies in the configuration and memory of those cells. The challenge in this is that, at present, the methods of destruction are harsh, akin to chemotherapy and certainly not something people would want to undergo for any but the most dangerous autoimmune conditions. A priority for the next few years is to find ways to selectively destroy immune cells safely and with few to no side-effects, at which point this type of immune reconstruction would be a very useful treatment for even minor autoimmunities. More pertinently, it would also open the door for the treatment of age-related dysfunction and failure of the immune system, a large component of the frailty of old age. Much of this decline is related to the accumulation of malfunctioning cells, or cells uselessly specialized to persistent pathogens like cytomegalovirus. If the slate could be wiped clean, we might expect there to be considerable improvement in immune response, even given the greater level of damage in cells and tissues characteristic of old age.

New clinical trial results provide evidence that high-dose immunosuppressive therapy followed by transplantation of a person's own blood-forming stem cells can induce sustained remission of relapsing-remitting multiple sclerosis (MS), an autoimmune disease in which the immune system attacks the central nervous system. Five years after receiving the treatment, called high-dose immunosuppressive therapy and autologous hematopoietic cell transplant (HDIT/HCT), 69 percent of trial participants had survived without experiencing progression of disability, relapse of MS symptoms or new brain lesions. Notably, participants did not take any MS medications after receiving HDIT/HCT. Other studies have indicated that currently available MS drugs have lower success rates.

In the HALT-MS trial, researchers tested the safety, efficacy and durability of HDIT/HCT in 24 volunteers aged 26 to 52 years with relapsing-remitting MS who, despite taking clinically available medications, experienced active inflammation, evidenced by frequent severe relapses, and worsened neurological disability. The experimental treatment aims to suppress active disease and prevent further disability by removing disease-causing cells and resetting the immune system. During the procedure, doctors collect a participant's blood-forming stem cells, give the participant high-dose chemotherapy to deplete the immune system, and return the participant's own stem cells to rebuild the immune system. The treatment carries some risks, and many participants experienced the expected side effects of HDIT/HCT, such as infections. Three participants died during the study; none of the deaths were related to the study treatment. Five years after HDIT/HCT, most trial participants remained in remission, and their MS had stabilized. In addition, some participants showed improvements, such as recovery of mobility or other physical capabilities.

Link: https://www.niaid.nih.gov/news-events/stem-cell-transplants-may-induce-long-term-remission-multiple-sclerosis

Rejuvenation Biotechnology Update for January 2017

The Methuselah Foundation and SENS Research Foundation have sent around the latest edition of the Rejuvenation Biotechnology Update, highlighting and explaining a few of the more interesting research results of recent months. It is a quarterly newsletter for members of the Methuselah 300, a more than decade-old group of advocates and supporters who each pledge to donate $25,000 over 25 years to help fund the development of therapies to treat aging. The first of the 300 helped to launch the Methuselah Foundation, and their continued support drew in the funding needed to eventually spin off the SENS Research Foundation as its own venture. While it was just thirteen years ago that the 300 was first mentioned, a lot has happened since then. Tempus fugit.

Only thirteen years, yes, but for me that seems like a long time past. Back then advocates for longevity science were few in number, working so very hard to raise a few thousand dollars here and a few thousand dollars there, while being roundly mocked for declaring that aging should and could be treated as a medical condition when people did deign to pay attention. How far we've come since then! The entire environment has changed, the attitudes of the scientific establishment are remade, the concept of medicine to address aging is discussed in the media on a regular basis, available funding is greatly multiplied, and the first SENS rejuvenation therapies are moving towards the clinic. There is a still a long way to go yet towards the goal of defeating aging and all age-related disease, but the beginning has been written and done: we have now entered into the next phase.

Rejuvenation Biotechnology Update, January 2017 (PDF)

Transplanted Senescent Cells Induce an Osteoarthritis-Like Condition in Mice.

This study provides evidence that adding senescent cells to a healthy joint can create a constellation of symptoms that resemble osteoarthritis. It is an important step in linking cellular senescence and osteoarthritic joint damage. However, the "smoking gun" that would really implicate senescent cells as a clinically-relevant target for osteoarthritis treatment would be to demonstrate that using senolytic drugs or genetic approaches to remove senescent cells from the joint of an animal with osteoarthritis leads to an improvement in osteoarthritis symptoms and the restoration of joint structure and function. Furthermore, the authors acknowledge that senescent cells may be one cause or a contributor to osteoarthritis, but osteoarthritis may also have other causes or contributing factors (such as chronic inflammation from other causes, mitochondrial dysfunction, and loss of glycosaminoglycans). So, we remain vigilant about the potentially-significant role of senescent cells is in the development of osteoarthritis.

Given that it is becoming increasingly clear that senescent cells significantly contribute to an overall phenotype of age-associated disease and dysfunction, these results are a promising step in the direction of implicating senescent cells as a therapeutic target for osteoarthritis. These findings no doubt hearten our colleagues at UNITY Biotechnology, who have identified osteoarthritis as their first target for senolytic drug therapy. Research on clearance of senescent cells as a strategy to correct aging damage is a high priority to SENS Research Foundation and Methuselah Foundation. Fortunately, this field seems to be advancing significantly and rapidly in the last few years. The company Oisín Biotechnologies (partially funded by SENS Research Foundation and Methuselah Foundation) is pursuing a "transient" (non-integrating) genetic approach to target and remove senescent cells from human bodies.

A single heterochronic blood exchange reveals rapid inhibition of multiple tissues by old blood.

This study represents an important advancement in technology to study blood-borne factors associated with youth and aging. It also contributes important findings that isolate the effect of blood-borne factors on tissue functions and injury repair in the context of aging. The authors anticipated that when the effects of blood alone were isolated, the findings would more relevant to human clinical applications. Some key findings from this study were that, at least when it came to neurogenesis, old blood seemed to inhibit neurogenesis more in young mice than young blood rejuvenated the brains of old mice. This would seem to implicate a greater increase in pro-aging factors, compared to the decrease in anti-aging factors, with age. This finding of old blood inhibiting neurogenesis in the hippocampus may be linked with the observed increase in β-2 microglobulin in young mice who received old blood, which occurred in the brain and muscle. However, the exact mechanism by which β-2 microglobulin levels came to be elevated in young mice who received old blood is still not clear. If it could be clarified, perhaps a potential therapeutic target or targets could be identified to lower β-2 microglobulin and other pro-aging factor levels in aged individuals.

One especially encouraging finding from this study was, as the authors put it, "the plasticity of age" - the observation that changes in tissues took place rapidly and old tissues were restored to a more youthful state within days of when blood exchange took place. And, unlike parabiosis experiments, a therapeutic approach based on blood exchange or blood filtration would be feasible in humans. Exchange transfusion is already an established treatment for several human autoimmune diseases where diluting auto-antibodies out of the circulation is beneficial, and exchange transfusion devices are currently available and FDA-approved for treatment of these diseases. Similarly, hemodialysis is a well-established procedure, and a more selective device that would scrub old blood of excessive "pro-aging" factors could extend this paradigm. The investigators in this study are looking to develop their findings into a clinical application for human patients soon: a startup company founded by a colleague is now preparing a clinical trial to adapt existing medical equipment test this very possibility in aging humans.

Vestibular Perceptual Thresholds Increase above the Age of 40.

The vestibular system in humans senses body motion and positioning of the body in space. The vestibular apparatus in the inner ear consists of a fluid-filled organ lined with sensing cells. The study found that after age 40, in both males and females, vestibular function steadily declined: vestibular perceptual thresholds increased; that is, the older a person gets, the more movement it takes for them to detect a change in position. According to the CDC, 1 out of 4 older Americans falls each year. In older individuals, falling is strongly associated with serious injuries and death. In fact, falls are the leading cause of injury and death from injury in Americans over age 65. The major factors for avoiding falls are functional balance and leg strength. The vestibular system plays a critical role in balance. So, understanding age-related declines in vestibular function may reveal critical insights into how to maintain balance and prevent falls.

Unfortunately, the major thing missing from this study was the identification of a mechanism for the decline in vestibular function after approximately age 40, and evidence supporting the identification of this mechanism. Several other studies have measured the number of vestibular hair cells (sensory cells) at various ages and showed a steady decline every year since birth. At first glance, this data does not seem to fit with the observation that vestibular function only starts to decline after age 40, this may be a case of a common phenomenon in aging that Dr. Aubrey de Grey has referred to as the "threshold of pathology." That is, humans may have enough vestibular hair cells so as to be redundant before age 40. Beyond that age, they may have lost enough cells that vestibular function starts to be affected as more cells die off. The authors speculate that free radical damage may be responsible for the death of vestibular hair cells with age, and further that vestibular function may serve as a reliable marker for the level of aging damage an individual has incurred, which can be measured noninvasively by simply testing vestibular function as they did in the current study.

Although the authors do not have experimental evidence that free radical damage is responsible for declining vestibular function with age, there is a range of evidence supporting the involvement of mutations in mitochondrial DNA and of mitochondrial free radical generation in vestibular damage from other causes. Vestibular damage is a major side-effect of the antibiotic gentamycin and others in its class, and free radicals are thought to be one of the mechanisms. Moreover, people with specific mutations in mitochondrial genes that code for the organelles that assemble proteins that are components of the mitochondrial energy production machinery are unusually vulnerable to this toxicity. Mice with a mutation that prevents the building of one of the complexes of the mitochondrial energy-production line develop vestibular damage, and human patients with the mitochondrial mutation disease Kearns-Sayre syndrome frequently have vestibular dysfunction as one of the many effects of the disease.

One way to address the rise in free radical damage with age is to prevent it at the source. This is the strategy behind SENS Research Foundation's "MitoSENS" program. Briefly: mitochondria in a subset of cells acquire large deletions in their DNA as individuals age, and the abnormal metabolic activity that cells harboring such mitochondria undertake results in a rise in oxidative stress in the body. To fix this problem, mitochondrial genes should be stably expressed in the cell nucleus instead of in the mitochondria, where these genes are more easily damaged. The strategy of MitoSENS is to fix the source of the damage: the inability of these dysfunctional mitochondria to generate the proteins they need to carry out normal metabolism with lower free radical production. If vestibular function is indeed connected to the rise of cells that have been taken over by mitochondria bearing such deletions and creating additional free radicals, this would enhance the value of the goals of the MitoSENS project, which could provide the benefit of preserving vestibular function and prevent the common, dangerous, and deadly scourge of falls.

In Search of Lipid Signatures of Longevity in Mammalian Species

The research here makes a good companion piece to older work in which scientists correlate the lipid composition of cell membranes to species longevity, in the course of evaluating what is known as the membrane pacemaker hypothesis. Among other things, this points to the significance of mitochondrial function and mitochondrial damage in aging, given that, all other things being equal, species characterized by more resilient mitochondrial structures appear to live longer. This is probably far from the only reason why there might be specific lipid signatures associated with longer-lived or shorter-lived species, however.

In contrast to average life expectancy that may change depending on living conditions, maximal lifespan (MLS) is a stable characteristic of a species. At the same time, MLS varies greatly among species. In mammals it ranges from 3-4 years in small rodents to as long as 150-200 years in bowhead whales. More remarkably, MLS evolves rapidly, resulting in markedly different lifespans and, consequently, different time of aging onset, even among closely related species. For instance, humans and macaques diverged only around 30 million years ago (MYA), yet over this time their MLS has diverged as much as three-fold.

Despite remarkable evolutionary plasticity of MLS, the existence and nature of the molecular mechanisms controlling this variation remains unclear. Most studies so far have focused on mechanisms of lifespan plasticity within species, resulting in identification of longevity-related pathways, such as insulin signaling pathways and targets of rapamycin pathway, shared across a wide range of animal species: from worms to mice. Genetic, dietary and pharmacological manipulation targeting these pathways resulted in more than 10-fold lifespan extension in short-living nematode worms, but only approximately 40% (1.4-fold) lifespan extension in short-living mammals such as laboratory mice. At the same time, natural variation in MLS among mammalian species exceeds 50-fold.

In this study we searched for a link between MLS and another marker of species' physiology - concentrations of hydrophobic metabolic compounds (henceforth referred to as "lipids" for simplicity). Recent scans of gene expression variation among 33 mammalian species with MLS differences of over 30-fold has shown that expression variation of 11-18% of analyzed 19,643 genes could be associated with MLS variation. There is however a stronger evidence of genetic changes in genes controlling lipid metabolism to play a role in human longevity, as well as in MLS differences among species, and changes in lipid saturation levels, pointing to lipids as a good potential target for investigation of molecular mechanisms underlying differences in MLS among mammalian species.

Our results show that long lifespan is associated with distinct lipidome features shared across three mammalian clades. Lipid predictors of long MLS differ across tissues, but overlap within brain and non-neural tissue types. The long MLS predictors identified in brain are especially conserved among clades, allowing long-living species identification within a clade solely based on lipid predictors from the other two clades. While little can be said about functional significance of these changes one potentially important feature stands out: the genomes of long-living primate and rodent species show increased evolutionary selection acting upon the amino acid sequences of enzymes linked to lipid predictors of long MLS. These enzymes cluster in specific functional categories associated with signaling and protein modification processes, as well as the corresponding cellular compartments: Golgi apparatus and plasma membrane.

Link: https://dx.doi.org/10.1038/s41598-017-00037-7

Glucose Deprivation in Alzheimer's Disease Progression

The progression of Alzheimer's disease, happening in the midst of aging in general, and often other unrelated neurodegeneration as well, is so complex and sweeping that every research group focuses down on just one part of the whole. It is like the parable of the elephant and the blind men, and has made it perhaps more challenging than it might otherwise be to understand and target root causes rather than intermediary, downstream processes in the pathology of the condition. You might look at yesterday's thoughts on Alzheimer's as a consequence of lack of oxygen in brain tissues and compare with this view of Alzheimer's as a lack of glucose, for example. These are just small pieces of a bigger picture, in a field in which there needs to be a lot more synthesis of disparate research into a uniform whole.

One of the earliest signs of Alzheimer's disease is a decline in glucose levels in the brain. It appears in the early stages of mild cognitive impairment - before symptoms of memory problems begin to surface. Whether it is a cause or consequence of neurological dysfunction has been unclear, but new research now shows unequivocally that glucose deprivation in the brain triggers the onset of cognitive decline, memory impairment in particular. The hippocampus plays a key role in processing and storing memories. It and other regions of the brain, however, rely exclusively on glucose for fuel - without glucose, neurons starve and eventually die.

The new study is the first to directly link memory impairment to glucose deprivation in the brain specifically through a mechanism involving the accumulation of a protein known as phosphorylated tau. Phosphorylated tau precipitates and aggregates in the brain, forming tangles and inducing neuronal death. In general, a greater abundance of tau tangles is associated with more severe dementia. The study also is the first to identify a protein known as p38 as a potential alternate drug target in the treatment of Alzheimer's disease. Neurons activate p38 protein in response to glucose deprivation, possibly as a defensive mechanism. In the long run, however, its activation increases tau phosphorylation, making the problem worse.

To investigate the impact of glucose deprivation on the brain, researchers used a mouse model that recapitulates memory impairments and tau pathology in Alzheimer's disease. At about 4 or 5 months of age, some of the animals were treated with 2-deoxyglucose (DG), a compound that stops glucose from entering and being utilized by cells. The compound was administered to the mice in a chronic manner, over a period of several months. The animals were then evaluated for cognitive function. In a series of maze tests to assess memory, glucose-deprived mice performed significantly worse than their untreated counterparts. When examined microscopically, neurons in the brains of DG-treated mice exhibited abnormal synaptic function, suggesting that neural communication pathways had broken down. Of particular consequence was a significant reduction in long-term potentiation - the mechanism that strengthens synaptic connections to ensure memory formation and storage.

Upon further examination, the researchers discovered high levels of phosphorylated tau and dramatically increased amounts of cell death in the brains of glucose-deprived mice. To find out why, researchers turned to p38, which in earlier work his team had identified as a driver of tau phosphorylation. In the new study, they found that memory impairment was directly associated with increased p38 activation. The findings also lend support to the idea that chronically occurring, small episodes of glucose deprivation are damaging for the brain. The next step is to inhibit p38 to see if memory impairments can be alleviated, despite glucose deprivation.

Link: http://www.templehealth.org/News/Default.aspx?nid=3626