at least this seems to be the case in drosophila…
“Rapamycin modulates tissue aging and lifespan independently of the gut microbiota in Drosophila”
I recently came across this paper, and I know we’ve had discussions here in the past on the method of action for rapamycin and longevity. Some people have suggested it may work via the microbiome. This paper seems to suggest that perhaps not…
Here, using Drosophila as a model organism, we show that rapamycin-mediated alterations in microbiota dynamics in aged flies are associated with improved markers of intestinal and muscle aging. Critically, however, we show that the beneficial effects of rapamycin treatment on tissue aging and lifespan are not dependent upon the microbiota. Indeed, germ-free flies show delayed onset of intestinal barrier dysfunction, improved proteostasis in aged muscles and a significant lifespan extension upon rapamycin treatment. In contrast, genetic inhibition of autophagy impairs the ability of rapamycin to mediate improved gut health and proteostasis during aging. Our results indicate that rapamycin-mediated modulation of the microbiota in aged animals is not causally required to slow tissue and organismal aging.