4.2 Pre-clinical studies of rapamycin in anti-aging
Rapamycin has been found to extend lifespan in diverse model organisms,
including yeast, fruit flies, and nematodes 146-148 .
Thus, studies have suggested that treating yeast with rapamycin,
although making them smaller, can extend their longevity in a process
that has been postulated to mimic caloric restriction149. Similarly, a landmark study by Harrison et al.
revealed that rapamycin extends longevity in mammals150. They found that when treating genetically
heterogeneous mice beginning at the age of 20 months with a daily dosage
of 2.24 milligrams per kilogram of body weight, rapamycin can extend the
lifespan of male mice by 9% and lifespan of female mice by 14%150. Remarkably, when increasing the dosage of
rapamycin 3-fold compared to the previous study, the lifespan of mice
was increased by up to 26% in female mice 151.
Moreover, rapamycin has also been demonstrated to have protective
effects against aging, which has been demonstrated in a high-profile
study, the Intervention Testing Program (ITP) 152.
This study used genetically outbred mice to test the potential of
multiple anti-aging manipulations, including drugs, diets, and other
interventions 153. Surprisingly, rapamycin is one of
the only two drugs (the other is acarbose) that had robust anti-aging
effect in the ITP experimental animal models.