Finding could help fight age-related diseases
John Cooke wants it to be clear that he and his fellow researchers at the Houston Methodist Research Institute have not discovered the fountain of youth.
“I’m not Ponce de Leon,” Cooke said in an interview, referring to the 16th century Spanish explorer who, legend has it, was seeking a water source capable of reversing aging.
But in a research letter just published in the Journal of the American College of Cardiology, Cooke and his colleagues report they have developed technology in their laboratory that rejuvenates human cells, raising the possibility of treatment for an array of age- related diseases.
Working with cells from children suffering f rom progeria, an extremely rare genetic disorder marked by rapid aging, the scientists from the Houston Methodist Research Institute discovered a “dramatic effect” on the lifespan and function of the cells.
“We can at least stall or slow down accelerated aging, and that’s what we’re working toward,” Cooke, department chair of cardiovascular sciences at Houston Methodist, said in a news release. “Our next steps are to start moving this therapy toward clinical use. We plan to do so by improving existing cell therapies. I want to develop a therapy for these children.”
The new research focused on telomeres, which are found at the end of chromosomes. Cooke likened a telomere to the tip of a shoelace, holding the chromosome together. They have also been compared to the fuse on a bomb, because they get shorter every time a cell divides. Eventually the cell can no longer divide and it dies.
Such shortening is typically associated with aging, and 12 of the 17 progeria patients studied — the oldest of whom was 14 — had shortened telomere, similar to what would be found in a healthy 69- year- old. The average person with progeria lives just 13 years, with heart attack and stroke a common cause of death.
The technology used by the researchers i nvolved prompting cells to produce a protein, telomerase, which can lengthen the telomere. This was done by delivering RNA to the cells that encode telomerase.
“When we lengthen telomeres, we can reverse a lot of the problems associated with aging,” Cooke said in a video accompanying the publication.
“We were not expecting to see such a dramatic effect on the ability of the cells to proliferate. They could function and divide more normally, and we gave them extra lifespan, as well as better function,” Cooke said.
The challenge now is finding a way to deliver the RNA into a human body as opposed to cells in a petri dish. RNA is fragile and breaks down quickly in the bloodstream, so Cooke said they are studying the use of nanoparticles to deliver the treatment.
In his medical practice, Cooke sees a lot of patients suffering from heart and vascular diseases caused by aging. He is hopeful the new findings will be as beneficial to them as they are to children undergoing rapidly accelerated aging.
“About a third of the people in this country succumb to strokes and heart attacks,” he said. “If we can fix that, we’ll fix a lot of diseases.”
A study published in the journal Nature in 2010 found that triggering telomerase production reversed aging in mice. But other studies have shown an increased cancer risk as cells stimulated with telomerase are again able to replicate.
Telomerase has become popular among many people hoping to combat aging, with some companies marketing costly telomerase activators in pill or liquid form.
Cooke does not want his research lumped in with the over-the-counter treatments for which he has seen no evidence of their effectiveness.
“I’m a physician. I’m skeptical, and any new therapies have to undergo the rigour of a randomized clinical trial and be shown to be safe and effective,” he said.
WE CAN AT LEAST STALL OR SLOW DOWN ACCELERATED AGING.