Scientists at Harvard Medical School have investigated why we age and have identified possible ways to reverse it. caused symptoms of aging, and showed that a system reboot could reverse the symptoms and extend lifespan.
Our genome contains the complete DNA blueprint found in every cell in our body. But it’s not the whole picture. An additional layer of information, known as the epigenome, sits above it, controlling which genes are switched on and off in different types of cells. It’s as if all the cells in our body work according to the same operating manual (genome), but the epigenome is like a table of contents that leads different cells to different chapters (genes). After all, lung cells require very different instructions than heart cells.
Environmental and lifestyle factors such as diet, exercise, and even childhood experiences can alter epigenetic expression over our lifetime. Epigenetic changes are associated with the rate of biological aging. However, it remains unclear whether they caused the symptoms of aging or were symptoms in themselves.
In a new study, researchers at Harvard University conducted experiments on mice to find out. The researchers used a system called induced changes in the epigenome (ICE) to accelerate the natural processes of DNA damage and repair in mice to see if this accelerated the symptoms of aging.
In mammalian cells, our chromosomes undergo one million DNA breaks per minute, and epigenetic factors orchestrate the repair very quickly before returning to their original position. The team engineered a mouse that experiences DNA breaks three times faster than his normal.
It turns out that over time, epigenetic factors become more “distracting”, and after repairing DNA breaks they don’t go back together, messing up the epigenome. Sure enough, by 6 months of age, mice showed physical signs of aging and appeared to be in much worse health than unedited mice of the same age.
With this, scientists say they have confirmed the role of the epigenome in aging. The next step was to test if we could do something about it. Therefore, the team administered a gene therapy cocktail of three genes known as Oct4, Sox2, and Klf4. They are active in stem cells, and the team found in a previous study that they could be used to restore vision in mice with age-related glaucoma.
In this case, biomarkers of aging were dramatically reduced in ICE mice. Their epigenome was unscrambled, restoring their tissues and organs to a more youthful state.
“It’s like restarting a dead computer,” said senior author David Sinclair of the study. “[It] I started an epigenetic program to restore the epigenetic information that I had when I was young in my cells. It’s a permanent reset. ”
The discovery is potentially huge, the team says. By addressing aging itself, many ailments that arise from this natural process can be more effectively treated.
“If that’s true, the underlying cause of cancer, diabetes, and Alzheimer’s could be the same, and reversing it could treat or cure age-related symptoms in one treatment. It means there is potential,” Sinclair said. Post to Twitter.
Much research is still needed to realize such ambitious goals, but work is already underway. A not-yet-peer-reviewed preprint paper administered the same gene therapy cocktail systemically to an old mouse, the human equivalent of 77. These mice lived 9% longer than untreated mice. rice field.
A new study was published in a journal cellThe team describes their work in the video below.
Epigenetics and Aging: Effects of DNA Breakage and Repair
Source: Harvard Medical School
