Illustration of the Rapamycin (Red) medication blocking a protein called mtor (blue)
Scientific photo library / Alamy
The anti -aging effects of drug repairing could at least partly be due to the prevention of DNA damage in our immune cells – an understanding that could help us to release its potential as a life number.
Originally developed as immune to people undergoing organ transplants, rapamycin blocks the action of the MTOR protein, which is the key to growth and cell division. In low doses, it has been shown that it increases lifespan in animals such as flies and mice, possibly interfering with processes that lead to signs of aging, such as inflammation, cell degradation and a reduced function of mitochondria that feed our cells.
Now Lynne Cox at the University of Oxford and his colleagues have discovered that rapamycin also seems to stop DNA damage in a type of immune cell. DNA damage is a major engine for aging our immune system, which accelerates aging throughout the body.
The researchers discovered this when treating human immune cells called T cells, a type of white blood cells that fights infections, with rapaamycin when they were also exposed to an antibiotic called Zéocine, which causes DNA damage.
They found that rapaamycin reduced DNA lesions and tripled the survival rate of cells compared to those exposed only to zéocine.
The researchers saw no evidence that this was happening following another of the effects of rapamycin, such as stopping cellular rupture. “Whether you use rapaamycin before inducing damage, during damage or after damage, we always see this mechanistic effect,” explains Ghada Alsaleh, member of the team, also at the University of Oxford.
The speed of the effect also suggests that this was happening directly. “The impact is so rapid, it seems that it has an impact on the response to DNA damage and the accumulation of [DNA] Brass in about 4 hours, so I don’t think it could be a downstream consequence of the affected by other things, ”explains Cox.
Matt Kaeberlein at the University of Washington in Seattle says that the study supports rapaamycin having a direct protective effect on DNA, but “stops at less than a definitive mechanism”. Researchers hope to find it by studying the changes induced by RAPamycin in RNA and proteins produced in immune cells.
In another part of the study, they affected nine men, aged 50 to 80, to take 1 milligram per day of rapaamycin or a placebo. After eight weeks, blood tests have shown that rapaamycin’s t cells have less DNA damage. There was also no drop in the overall number of white blood cells in either group, which suggests that rapaamycin does not negatively affect the immune function. “We have shown that it is not harmful in low doses, and it is a critical point,” explains Cox.
The fight against DNA damage to immune systems could be a path to reducing global aging, explains Cox. And Alsaleh says that rapamycin could even be used in prevention, perhaps to remove DNA damage to astronauts exposed to cosmic radiation.
“Rapamycin could also be particularly useful for the aspects of aging where DNA damage is a main driver, like skin aging,” explains Kaeberlein, stressing that topical rapamycin reduces the markers of aging in human skin. But he adds that, as the experiences of the Cox team used an antibiotic to cause DNA damage, extrapolation with damage caused by other causes, such as radiation, should be prudent.
Zahida Sultanova at the University of East Anglia, in the United Kingdom, notes that as the experience controlled by placebo has only been carried out on older men, it is also important to do trials in women and people of different ages. Studies in non -human animals suggest that rapamycin can have specific sex and age specific effects.
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