A most interesting New Scientist article looks at hints of an existing mechanism by which age-damaged mitochondria could be repaired. Given the central role played by mitochondrial degeneration in aging, this would be a very big deal if it could be exploited: "Healthy cells seem to have shown an amazing ability to breathe new life into damaged ones by rejuvenating their defunct mitochondria. It is an extraordinary and controversial claim. But if confirmed it could offer a way to prevent a range of harrowing metabolic diseases that affect millions of people. Experts in mitochondrial research have yet to be convinced. They say the work purporting to show the effect has yet to be comprehensively peer-reviewed, and is so potentially ground-breaking that more evidence is needed."
Link: http://www.newscientist.com/channel/health/mg18925364.200