London: Scientists have found a way to reverse aging, unlocking the secret of eternal youth and paving the way for a drug to keep one "forever young".
Lives could be longer and healthier, free from illnesses such as Alzheimer's and heart disease, with skin and hair retaining their youthful lustre. Increasing the number of years of healthy life would greatly ease health service costs and reduce the burden on families of caring for frail relatives, the Daily Mail reported, citing the journal Nature.
The research, carried out by oncologist Ronald DePinho of Harvard University, reversed the effects of ageing in animals for the first time in experiments on mice.
Before treatment, the mice's skin, brains, guts and other organs resembled those of an 80-year-old person. But within just two months of being given a drug that switches on a key enzyme, the creatures had grown so many new cells that they had almost completely rejuvenated. Remarkably, the male mice went from being infertile to fathering large litters.
The breakthrough centres on structures called telomeres - tiny biological clocks that cap the ends of chromosomes, protecting them from damage. With time, the telomeres get shorter and shorter, raising the odds of age-related diseases such as Alzheimer's.
Eventually the telomeres become so short that the cells die. An enzyme called telomerase can rebuild the telomere caps but is normally switched off in the body.
DePinho succeeded in shocking the enzyme back to life in mice that had prematurely aged in a way designed to mimic the human ageing process.
He expected the technique to halt or slow the ageing process and so was stunned to find that it reversed it.
DePinho believes it should be possible to make a pill that does the same in people.
But there are important caveats. High levels of telomeres can fuel the growth of cancers, and one drug is unlikely to smooth away all the problems of ageing.
"There are multiple mechanisms that conspire to lead to ageing. So, although we think that telomeres are important, there are other factors that come into play," DePinho told the Daily Mail.
Dr Steven Artandi, a telomere expert at Stanford University, US, described the study as "beautiful" but cautioned that an anti-ageing drug is still more than ten years away.