Researchers in the United States have managed to restore sight to old blind mice and have also developed healthier brains, muscle tissue and kidneys. The researchers think aging can be reversed in mice, and they aim to try and apply this to humans.
The study was conducted by researchers led by David Sinclair, professor of genetics at Harvard Medical School’s Blavatnik Institute, and was published Thursday in the journal Cell.
Sinclair said experiments show that aging is a reversible process that can be pushed “back and forth at will.” He added that our bodies contain a backup copy of our youth that can be stimulated to regenerate, according to a CNN report.
The study challenges the scientific belief that aging is caused by genetic mutations that erode our DNA, creating an arena of damaged cellular tissue that can lead to deterioration, disease and death.
“It’s not the damage that makes us age,” Sinclair said, “we think it’s a loss of information, a loss of the cell’s ability to read its original DNA, so that she forgets how to function.”
Jae Hyun Yang, a genetics researcher at Sinclair’s lab who participated in the study, said he expects the results “to change the way we view the aging process and our approach to treating related diseases. to aging”.
Changes in the epigenome control aging
While DNA can be thought of as the hardware of the body, the so-called epigenome is the program.
Epigenomes are proteins and chemicals that sit on every gene, waiting to tell the gene what to do, according to the National Human Genome Research Institute in the US.
The genome literally turns genes on and off. This process can be triggered by pollution, environmental toxins, and human behaviors such as smoking, following an inflammatory diet, or suffering from chronic lack of sleep.
“The amazing result is that there is a backup copy of the software in the body that you can reset,” Sinclair said. “We explain why this software is corrupted and how we can reboot the system by pressing a reset switch that restores the cell’s ability to read the genome correctly again.” Like she was young.”
He added that it doesn’t matter if the body is 50 or 75, healthy or sick. Once this process has started, “the body will then remember how to regenerate and become young again, even if you are old and sick. Now what this program is, we don’t know yet. At this point, we just know that we can turn the knob.”
To test this theory, he set out to accelerate the aging of mice without causing mutations or cancer.
The mice looked like they were one year old, but acted like they were two years old, meaning they had aged before their time.
Become young again
Then the scientists reversed the process. The team created a combination of three “Yamanaka factors”, adult human skin cells that have been reprogrammed to behave like embryonic or pluripotent stem cells, capable of developing into any cell in the body.
Yamanaka factors are a group of protein transcription factors that play a vital role in the formation of pluripotent stem cells, cells that have the potential to grow into any cell in the body. They control how DNA is copied to be translated into other proteins.
The agents were injected into damaged retinal ganglion cells in the back of the eyes of blind mice, and the mice regained most of their sight. Then the team treated brain, muscle and kidney cells and restored them to a much younger age, according to the study.
“One of our breakthroughs was realizing that if you used this specific set of pluripotent stem cells, the mice wouldn’t go back to age zero,” Sinclair said. “Instead, the cells go back to between 50% and 75% of their original age, and they stop and they don’t. “You rejuvenate… How do cells know how to do that, we don’t understand yet.”
He explained that his team reset the cells in mice several times, which showed that aging can be reversed more than once, but decades may pass before clinical trials in humans to fight. against aging begin, and are analyzed, and if safe and successful, they are expanded to the size required for approval.American Federalism.
Just as harmful agents can disrupt the epigenome, healthy behaviors can repair it, Sinclair said. “We know this may be true because people who led healthy lifestyles had shorter biological lifespans than ones that did the opposite,” Sinclair said.
What are Sinclair’s best tips?
Focus on plants for nourishment, eat less, get enough sleep, exercise vigorously for 10 minutes, 3 times a week to maintain muscle mass and maintain good social relationships.
On the other hand, scientists who were not involved in the work point out that the suggestions regarding the age change are premature. “These studies use reprogramming factors to reverse epigenetic changes that occur during aging,” said Matt Kaeberlin, a gerontologist at the University of Washington in Seattle, but that’s a far cry from rejuvenating an old animal.
Jan Vij, a geneticist at the Albert Einstein College of Medicine, and he and others point out that aging is a complex process with many contributing factors.
Molecular biologist Wolf Rick, director of the Altus Cambridge Institute of Science, praises the sophistication and precision of the Harvard team’s study, but says the team’s indirect method of inducing genetic changes with DNA breaks that could have other effects make it difficult to prove that these changes are the ones that cause aging.