Forget the fountain of youth. Although a bevy of recent scientific papers have described how to extend lab animals' life spans, the way to make money off their findings is not with drugs that prevent aging, but with ones that prevent the diseases of aging. At least that's what the founders of Sirtris Pharmaceuticals think. Spun out of Harvard University about six months ago, the company aims to translate antiaging research into medicines for diabetes.

For decades, researchers have known that limiting lab animals' calorie intake not only extends their lives but also prevents diabetes and other age-related ailments. Recent studies suggest that a boost in an enzyme called SIRT1 may be the explanation. Now, Sirtris cofounder and Harvard Medical School professor David Sinclair says he and his colleagues have found evidence that SIRT1 is involved in glucose metabolism. Sinclair believes that a drug that activates the SIRT1 enzyme could reverse the problem that underlies type 2 diabetes: cells' inability to absorb glucose.