Commentary on Rapamycin
A commentary on recent research into the effects of rapamycin on longevity: "Aging is a complex process associated with accumulation of damage, loss of function and increased vulnerability to disease, leading ultimately to death. Despite the complicated etiology of aging, an important discovery of recent years has been that simple genetic alterations can cause a substantial increase in healthy lifespan in laboratory model organisms. Many of these longevity-extending mutations down-regulate the activity of the mTOR/S6K pathway suggesting that reduced Tor/S6K signaling promotes entry into alternative phases normally entered during periods of starvation. In fact, dietary restriction (DR), a reduction in food intake without malnutrition, lowers Tor/S6K signaling and extends the average and maximum life span of a variety of organisms including yeast, flies, worms, fish, and rodents. ... Recently, it has been demonstrated that supplementation with rapamycin (an inhibitor of mTOR) started both at 9 and 20 months of life determines a small but significant extension of average and maximal life span in genetically heterogeneous male and female mice ... More studies are needed to understand benefits and side-effects of rapamycin supplementation in different strains of mice and in monkeys as a candidate cancer-preventive and life-extension pharmacological agent. However, the efficacy of intermittent rapamycin treatment in cancer prevention and life span extension [is] very promising since it is likely to reduce the side effects associated with chronic treatment."