For all that I think it isn't an efficient path forward, one likely to produce meaningful results in moving the needle on human life spans, there is considerable interest in testing combinations of existing drugs and various dietary compounds in mice to see if healthy life is extended. I expect that as public interest grows in the prospects for aging research to move from being an investigative to an interventional field, wherein researchers are actively trying to treat aging, we'll only see more of this. There is certainly a sizable portion of the research community who think that the the best path ahead is in fact the pharmaceutical path of drug discovery in search of ways to slightly slow the aging process. To their eyes slightly slowing the aging process is all that is plausible, and adding five healthy years to life by 2035 would be a grand success. Google's Calico initiative looks set to take that path, for example, which I is why I'm not all that hopeful it will produce meaningful results in terms of healthy years gained and ways to help the old suffer less.
There is a considerable overlap between researchers aiming to gently slow aging via drug discovery and researchers whose primary motivation is still investigation, not intervention: to produce a complete catalog of metabolism and how it changes with age, and it's someone else's problem to actually use that data. So we have, for example, the Interventions Testing Program at the NIA. This program was long fought for by researchers tired of the lack of rigor in most mouse life span studies, and the people involved are essentially engaged in replacing a lot of carelessly optimistic past results with the realistic view that very little other than calorie restriction and exercise actually does reliably extend life in mice if you go about the studies carefully. This is good science, but it isn't the road to extended human life spans: it instead has much more to do with understanding the process of aging at a very detailed level. That task is vast and will take a very long time even in this age of computing and biotechnology.
To my eyes the right way to go is the repair approach: build the biotechnologies needed to repair the forms of cellular and molecular damage produced as a side-effect of the normal operation of metabolism, and which clearly distinguish old tissues from young tissues. If you want rejuvenation of the old, a path to adding decades to healthy life, and to eliminate all age-related disease, then repair is the way to go. Fix the damage, don't just tinker with the engines of life in ways that might possibly slow down damage accumulation just a little. This strategic direction can allow researchers to largely bypass the great complexity of the progression of aging and focus instead on fixing things that are already well known and well cataloged. But I say this a lot, and will continue to do so until more than just a small fraction of the research community agree with me.
Back to mice and life span studies: in this day and age institutional research is far from the only way to get things done. Early stage research is becoming quite cheap as the tools of biotechnology improve, and the global economy allows quality scientific work to be performed in locations that are lot less expensive than the US or Western Europe. We have crowdfunding, the internet, and a supportive community, which means that any group of ambitious researchers can raise a few tens of thousands of dollars and set an established lab in the Ukraine to running a set of mouse life span studies. So that happened back in 2013, and has been ongoing since then despite the present geopolitical issues in that part of the world. It is perhaps worth noting that this is the same group that found no effect on longevity from transfusions of young blood plasma into old mice. The studies mentioned below used pre-aged mice, starting at old age as a way to try to discover effects more rapidly, an approach that is fairly widespread.
Dear contributors, we wish you a happy New Year! We are sorry to be taken by a very-expected but very time-consuming c60 lifespan study to digest the data in a way to make the long report we had announced. So, for the New Year and in order for you not to wait longer, please find at least the main results so far:
1) 23 months old C57BL6 mice received a mixture of 6 therapies that had already been reported to extend the lifespan of mice: Aspirin; Everolimus (mTOR inhibitor, similar action as rapamycin); Metoprolol (beta blocker); Metformin (anti-diabetic drug); Simvastatin (lowers LDL cholesterol); Ramipril (ACE inhibitor).
The drugs were given in the food, at doses that had been reported to extend lifespan ... when taken individually. Some people are given that combination of medicines so we hoped that the drug interaction would not be too damaging, and we had wondered if some lifespan synergy within some of these drugs could lead to an overall high lifespan (eg if the different drugs improve different functions). But we observed a lifespan reduction in males and in females.
2) In the food of some remaining females we mixed low doses of 4 medications against cardiovascular conditions: Simvastatin; Thiazide (lowers blood pressure); Losartan potassium (angiotensin receptor blocker, lowers blood pressure); Amlodipine (calcium channel blocker, lowers blood pressure).
The question was: taken at a low-to-medium dose, could these drugs that many aged persons take have some overall preventive effect? We transposed to mice an ongoing polypill clinical trial in the UK, using a basic human-mouse conversion scale. Again, a decrease in lifespan was observed.
3) Adaptations of the first combination of drugs actually extended lifespan!
We started at age 18 months instead of 23 months, reduced the dose (as a function of weight) and gave a) the 6 compounds b) 'only' aspirin+metformin+everolimus. The results are to be analysed in greater details as we haven't analyzed the latest data yet. Also, whatever the refined analysis, we would already like to indicate that it would be good to reproduce the experiment in some other conditions, eg hybrid mice; in particular as the mortality rates of these mice was higher than the first series (but in a consistent way that supports the life extending effect).
4) Ongoing C60 experiments
After many difficulties in setting the experiment (cross-border transportation in current geopolitical times, checking absorption in mice/ detecting C60/correct source of C60, administration tried in food and replaced by gavage, training for gavage and various measures) we have transposed the popular lifespan test with c60 fullerenes reported in rats by Baati et al. to mice (CBA strain, common in the lab) and with more animals (N=17 per group). There are three groups (gavage of water, of olive oil, of C60 dissolved in olive oil), there are ... a lot of health measures and a lot of gavage (at the beginnings of the experiment as administrations are first very frequent and then gradually less frequent). Given that the experiment starts with mid-aged animals, the results are expected for the beginning of 2016.
The original C60 results from a few years back were greeted with some skepticism in the research community, given the very large size of the effect claimed and the small number of animals tested. There was, I think, also a certain annoyance: now that someone had made what was on the face of it an unlikely claim of significant life span extension via administration of C60, then some other group was going to have to waste their time in disproving it. We'll see how that all turns out, I suppose. This is science as it works in practice.
At some point the broad structural classes of research illustrated by the Interventions Testing Program and this crowdfunded mouse study will meet in the middle, and the process of funding and organizing scientific programs will be a far more complicated, dynamic, and public affair than is presently the case. I think this will be for the better. All that we have we owe to science, and a majority of the public thinks all too little of the work that will determine whether they live in good health or suffer and die a few decades from now. The more they can see what is going on the better for all of us in the end, I think.