Scientists discover how to keep the body young despite age
Muscles have a cleaning system that eliminates waste and preventing degenerate over the years, as scientists have discovered the Universitat Pompeu Fabra (UPF) today presented its findings in the journal Nature.
When this cleaning system stops working properly, the muscles go into senescence. Then, stem cells lose the ability to regenerate tissue and muscle is weakened. It’s something that happens gradually from the fifth decade of life and that is observed extreme way elderly people who forces them fail.
But when the cleaning system is restored, as have researchers with drugs, muscle tissue can regenerate again and retrieves the lost vigor. So far the experiments have been performed in mice and in human cells in the laboratory.
Since the molecules involved in the cleaning system of muscle cells are the same in mice and in human body, “it should be possible to restore the regenerative capacity and muscle strength also in people,” says Pura Muñoz-Cánoves, ICREA researcher at UPF who led the work.
In fact, there are already approved drugs on the market that, in research, have shown ability to rejuvenate muscle tissue. Specifically, the team has experienced UPF rapamycin (an immunosuppressant which is mainly used to prevent organ rejection after a transplant) and Trolox (a similar antioxidant vitamin E).
Some pharmaceutical companies have also developing drugs that act on the mechanism identified in muscle regeneration research. Looking ahead, based on the results reported in Nature, they could develop new drugs that maximize the ability of tissue regeneration and minimize side effects.
The first candidate to receive the rejuvenating treatment would be elderly people weakened by sarcopenia, ie the loss of muscle mass, Muñoz-Cánoves reports. It could also be effective in adults weakened by cachexia, which is a tissue atrophy associated with diseases such as cancer, tuberculosis or AIDS. Or it could be useful to accelerate the healing of muscle injuries in athletes, since healing time depends on the ability of muscle regeneration, which in turn depends on efficient removal of waste from cells.
The cleaning system, technically called autophagy, “is like a vacuum,” says Muñoz-Cánoves. Removes components of cells stop functioning properly and become toxic. These components range from individual molecules (free radicals or damaged proteins) to whole organelles (such as mitochondria or ribosomes).
Since all organs and tissues of the human body depend on autophagy, Muñoz-Cánoves believes that the same system could be key to slow aging in other organs, and it could be useful to increase their regenerative capacity and rejuvenate. “I think it must be so because every house has to be cleaned, and autophagy is a very fundamental cleaning mechanism in living organisms,” says the researcher. But he warns that “we have not proven that our research has been limited to muscle tissue.”
In muscle, equipment UPF autophagy has been shown to maintain the ability of stem cells to regenerate tissue. And when autophagy no longer efficient and begin to accumulate waste, stem cells enter senescence and lose their regenerative capacity.
“We were surprised to discover this,” says Muñoz-Cánoves. “When you stop to think about it, it makes sense, because the stem cells need to break free of waste accumulate every day to work properly.” But despite intensive research in the last decade on the biology of aging, “this is the first time a relationship between declining and aging autophagy in mammalian tissue is observed.”
The work reported in Nature, whose first author Laura Garcia-Prat, gives meaning to research published earlier longevity. It was noted in particular that rapamycin prolongs life in various species, including mammals such as mice, but had not explained why. They it was also observed that metformin seems to slow aging in people who take it for the treatment of type 2 diabetes, to the point that there is a clinical trial underway to evaluate its potential to extend life.
Both rapamycin and metformin act on molecules that regulate autophagy and have now been shown to be essential to maintain the capacity to regenerate muscles. “Although senescence due to aging is often seen as an inevitable and irremediable process, we demonstrate that the internal clock of aging stem cells can be manipulated with drugs,” the researchers conclude in Nature UPF.
Courtesy Car Service Barcelona