Here are a few links of interest for you to peruse this Sunday; thanks go to the busy infomorphs of the sci.life-extension group for the first few. These folks perform a very useful service for the rest of us, taking their valuable time to sort through a great deal of data in search of connections and items of note.

Uncoupling protein homologs may provide a link between mitochondria, metabolism and lifespan:

Uncoupling proteins (UCPs), which dissipate the mitochondrial proton gradient, have the ability to decouple mitochodrial respiration from ATP production. Since mitochondrial electron transport is a major source of free radical production, it is possible that UCP activity might impact free radical production. Free radicals can react with and damage cellular proteins, DNA and lipids. Accumulated damage from oxidative stress is believed to be a major contributor to cellular decline during aging. If UCP function were to impact mitochondrial free radical production, then one would expect to find a link between UCP activity and aging. This theory has recently been tested in a handful of organisms whose genomes contain UCP1 homologs. Interestingly, these experiments indicate that UCP homologs can affect lifespan, although they do not support a simple relationship between UCP activity and aging.

The plasma membrane redox system in aging:

Oxidative stress over time leads to the accumulation of damaged macromolecules and to profound physiological changes that are associated with several age-related diseases. The plasma membrane redox system (PMRS) appears to attenuate oxidative stress acting as a compensatory mechanism during the aging process. The PMRS appears to play a protective role during mitochondrial dysfunction to provide cells with a survival mechanism by lowering oxidative stress.

Plasma membrane redox systems across various species form a big topic - big enough for their own conference. As you might note from the papers above, or indeed from pretty much anything I post here on the topic of mitochondria, metabolism is a fearsomely complex system. Greater understanding of the biochemistry of metabolism could lead to technologies of optimization - meaning least amount of age-related damage generated - that are demonstrably better than the practice of calorie restriction. Don't hold your breath there, however; this has the look of a topic that will still be hotly debated and the subject of ever-deeper investigation in 2016 and 2026. Meanwhile, calorie restriction is as simple a matter as putting thought into eating less in the right way. More to the point, tinkering with metabolic optimization seems to be a far less effective path forward than to aim at directly and effectively repairing what we know to be the root biochemical causes of aging.

To finish up, you'll find a set of sizeable videos of a Brian Wowk presentation on cryonics and vitrification in a thread over at the Immortality Institute.

Dr. Brian Wowk's presentation on Suspended Animation by Vitrification at the Life Extension Conference is now available ... It is recommended that you choose to "Save" the files rather than stream them online

Vitrification, as I've noted before, is a fascinating topic in and of itself. It shows potential to become the spin-off, revenue-generating infrastructure technology that the cryonics industry needs in order to support further growth. Alcor has been moving forward with this; a good thing in my book. If you're interested in learning more, one of the papers in the latest Rejuvenation Research was co-authored by Wowk:

Until recently, the cryopreservation of organs has seemed a remote prospect to most observers, but developments over the past few years are rapidly changing the scientific basis for preserving even the most difficult and delicate organs for unlimited periods of time. Animal intestines and ovaries have been frozen, thawed, and shown to function after transplantation, but the preservation of vital organs will most likely require vitrification. With vitrification, all ice formation is prevented and the organ is preserved in the glassy state below the glass transition temperature (TG). Vitrification has been successful for many tissues such as veins, arteries, cartilage, and heart valves, and success has even been claimed for whole ovaries. For vital organs, a significant recent milestone for vitrification has been the ability to routinely recover rabbit kidneys after cooling to a mean intrarenal temperature of about -45°C, as verified by life support function after transplantation. This temperature is not low enough for long-term banking, but research continues on preservation below -45°C, and some encouraging preliminary evidence has been obtained indicating that kidneys can support life after vitrification.

Technorati tags: aging, biotechnology, cryonics, medical research

Posted by Reason at May 21, 2006 3:58 PM | TrackBack (0)