Collecting Cellular Junk
Newer longevity science blog Green Light Go here looks at the harmful accumulation of metabolic byproducts and other junk such as lipofuscin in our cells with age: "I just finished an entry for the SOA timeline on the 1970s discovery that nematodes collect inactive enzymes and molecules as they grow older. The main idea being that the body is unable to clear out the junk inside cells and that the energy cost of carrying this junk leads to senescence, or aging. The theory reminded me of a similar finding by Coleen Murphy who found that long lived daf-16 elegans mutants lived longer in part because they encoded antimicrobial lysosomes, that helped to clear out microbes that would get "packed" inside the nematodes precipiating senescence and eventually their death. As far as I know, the reason for the slow decline in enzyme activity and for the collection of intracellular junk is still unknown. Why isn't our body clearing this stuff out and selling it on ebay? The SENS foundation, which is perhaps the biggest player in anti-aging research, is pushing forward with a solution anyway. Their strategy is to find enzymes manufactured by soil bacteria and fungi that can then be applied therapeutically to help clear junk out of cells. ... It is going to be interesting in the future to see what result comes of this. Both for understanding the chemical mechanism of the collection of junk, and the therapeutic solutions which can get rid of it."
Link: http://greenlightgo.healthaliciousness.com/2009/07/01/growing-old-and-collecting-cellular-junk/