Researchers in the United States have succeeded in restoring sight to old, blind mice, and have also developed younger-looking brains, muscle tissue and healthier kidneys.

The researchers believe that aging can be reversed in mice, and they aim to try to 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 the 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 report in CNN.

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 causes us to age," Sinclair said. "We think it's a loss of information, a loss of the cell's ability to read its original DNA, so it forgets how to function."

Jae Hyun Yang, a genetics research fellow in Sinclair's lab who was involved in the study, said he expects the findings "will change the way we look at the aging process and the way we approach treatment of aging-related diseases."

Changes in the epigenome control aging

While DNA can be seen as the hardware of the body, the so-called epigenome is the programme.

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, eating an inflammatory diet, or suffering from a 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 restart the system by hitting a reset switch that restores the cell's ability to read the genome correctly again." As if she were young."

He added that it does not matter if the body is 50 or 75 years old, healthy or diseased.

Once this process begins, "the body will then remember how to regenerate and become young again, even if you are old and sick. Now, what that program is, we don't know yet. At this point, we just know we can flip the switch."

To test this theory, he set out to speed up the aging of mice without causing mutations or cancer.

The mice looked one year old, but acted as if they were two years old, meaning they had grown old prematurely.

To 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.

The 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 become 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 at the back of the eyes of blind mice, and the mice regained most of their sight.

Next, 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 the realization 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 get younger... How the cells know to do this, 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 any clinical trials in humans to combat aging begin, and they are analyzed, and if they are 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 fix it, Sinclair said. "We know this may be true because people who lived a healthy lifestyle had a shorter biological lifespan than those who did the opposite," Sinclair said.

What are Sinclair's top tips?

Focus on plants for food, eat less, get enough sleep, exercise vigorously for 10 minutes, 3 times a week to maintain your muscle mass, and maintain good social relationships.

criticism

On the other hand, scientists who were not involved in the work stress that suggestions about changing the age are premature.

"These studies use reprogramming factors to reverse the epigenetic changes that occur during aging," Matt Kaeberlin, a gerontologist at the University of Washington Seattle, told Science. But that's a far cry from making an old animal young again.

Jan Vij, a geneticist at Albert Einstein College of Medicine, and he and others stress 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 accuracy 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 makes it difficult to prove that these changes are that cause aging.