NEW YORK (AP) – Call them zombie cells – they refuse to die.
Studies suggest that when they develop in your body, they promote aging and the accompanying diseases, such as osteoporosis and Alzheimer's disease. Researchers are studying drugs that can kill zombie cells and possibly treat the problems they cause.
The fundamental goal is to combat aging itself, which will hopefully delay as a group the onset of age-related diseases and disabilities, says Dr. James Kirkland, Geriatric Specialist, Mayo Clinic, Rochester, Minnesota. It is a contrast to playing an "ugly game" to treat one disease to see another develop, he said.
The search was carried out mainly in the mouse. Earlier this year, the first test in humans was released and provided tantalizing results.
Zombie cells are actually called senescent cells. They start normally, but then experience stress, such as damage to their DNA or a viral infection. At this point, a cell may choose to die or become a zombie, thus entering a state of suspended animation.
The problem is that zombie cells release chemicals that can harm normal cells nearby. This is where the problem begins.
What kind of problem? Studies in mice have shown that drugs that eliminate zombie cells – called senolytics – improve an impressive list of pathologies, such as cataracts, diabetes, osteoporosis, Alzheimer's disease, Alzheimer's disease. 39 enlargement of the heart, kidney problems, blockage of the arteries and aging of the patient. associated muscle loss.
Studies in mice have also shown a more direct link between zombie cells and aging. When drugs targeting these cells were administered to aged mice, the animals showed better walking speed, adhesion and endurance on a treadmill. Even when the treatment was applied to very old mice, the equivalent of 75 to 90 years, its lifespan was prolonged by 36% on average.
Researchers have also shown that zombie cell transplantation in young mice age them: their maximum walking speed slowed down, their muscle strength and stamina decreased. Tests have shown that implanted cells convert other cells into zombies.
Kirkland and his colleagues published this year the first study of a zombie cell-based treatment in humans. It involved 14 patients with idiopathic pulmonary fibrosis, a generally fatal disease that healed the lining of the lungs. The risk increases with age and the lungs of patients show signs of zombie cells.
In the preliminary experiment, after three weeks of treatment, patients improved certain measures of their fitness, such as walking speed. Other measures have not shown improvement.
Overall, the results are encouraging and "it really inspires enthusiasm to pursue the most rigorous studies," said Dr. Gregory Cosgrove, Chief Medical Officer of the Pulmonary Fibrosis Foundation, who played no role in the study.
The field of zombie cells is still young. But Kirkland estimates that at least a dozen companies have formed or have made efforts to continue their treatments. He holds shares in one.
In addition to age-related diseases, anti-zombie drugs could also be helpful in treating premature aging of cancer survivors, resulting in the early onset of certain diseases, said Laura Niedernhofer of the 39, University of Minnesota.
Some of these drugs have been approved for other uses or are even sold as supplements. But Niedernhofer and Kirkland insist that people should not try them alone or the doctors who prescribe them, for the uses currently being studied, because one must start by deepening the research.
Niedernhofer said that the best drugs could still be coming. The goal is not to prevent stressed cells from turning into zombies, she says, as they could become cancerous. The goal is to cause the death of already transformed cells or to limit the damage that they cause.
And what about healthy people who want to protect themselves from aging? It's possible, but very far after studies have established that the drugs are safe enough, she said.
"We could not do it," Kirkland said.
In any case, the experts are impressed by the research done so far.
"I think it's very exciting," said Dr. George Kuchel of the Center on Aging at the University of Connecticut in Farmington. The results of the animal studies are "very dramatic. These are very convincing data. "
Nir Barzilai, an aging researcher at the Albert Einstein College of Medicine in New York City, said he thought targeting zombie cells would play a role in the overall effort to delay, stop, and possibly reverse aging.
So much research suggests that they promote aging that "we know it should be true," he said.
The Associated Press Health and Science Department is supported by the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.