What is rapamycin?
Rapamycin is an antibiotic of natural origin, produced by a soil bacterium, Streptomyces hygroscopicus. It was first isolated from a soil sample from Rapa Nui Island (Easter Island), after which it is named. Rapamycin, however, is also known as Sirolimus. Rather than as an antibiotic, however, this molecule has been approved by the U.S. Food and Drug Administration (FDA) and the European Medicine Agency (EMA) as a drug to prevent rejection of newly transplanted organs due to its ability to reduce the immune response.
How does it work?
In mammals, rapamycin acts on an enzyme that can regulate the growth, proliferation and survival of our cells.
Precisely because it constitutes the main target of rapamycin, this enzyme has been named mammalian Target Of Rapamycin(mTORThe mTOR (mammalian target of rapamycin) is a set of enzymes (route) that react to food-nutrients, breaking them down and recombining them to build new proteins useful for the "growth of the body". They react to specific hormonal stimuli (Insulin and IGF-1) thus becoming the center of control of growth and cell proliferation in metabolism. This metabolic route is also responsible for the elimination of old and defective cells (Cellular Autophagy) with the double advantage of recycling the fundamental components to produce new cells and eliminate them to prevent them from triggering degenerative and inflammatory processes.).
Why is rapamycin considered a longevity molecule?
Studies have shown that rapamycin stimulates the synthesis of particular proteins called histones, which interact with DNA and
have the fundamental function of allowing it to compact itself within the nucleus of the cell. In practice, histones function for DNA like real spools, like the ones on which sewing thread is wound. Without histones, our cells would not be able to survive, and even small mutations in these special proteins are often lethal. Histone expression naturally decreases duringaging, but it has been seen that the phenomenon appears to be counteracted by the administration of rapamycin, at least in fruit flies and mice, and especially in the intestinal cells of these animals. Here, then, is one of the hypotheses that would explain its effect on longevity: administered over a period of three months to 20-month-old mice (which is equivalent to about 60-65 years in humans), rapamycin was shown to extend their lives by about 50 percent.
Does it have side effects?
Administration of rapamycin at the dosages that are used to prevent rejection of newly transplanted organs can cause numerous side effects
even serious ones, including increased cholesterol and blood glucose (with possible onset of diabetes), accelerated heart rate, slowed wound healing, formation of ulcers in the mouth, and the appearance of menstrual disorders. For this reason, part of the scientific community is focusing research in this area on the possibility of administering low dosages of this molecule and for short periods of time.