Secret to 'eternal youth' is an OVARY transplant: Swapping older organs for young ones can slow the aging process.
Researchers say swapping older ovaries for young ones in mice can cut the risk of age-related health problems, including heart disease, arthritis, immune, brain and liver function, as well as increasing longevity.
The discovery holds out the possibility of not only a longer life but old age free of the infirmities that afflict post-menopausal women.
Lead researcher Professor Jeffrey Mason, of Utah State University, said: "It is amazing and very exciting. In our study mice didn't look old when they were old."
Ovaries produce and release eggs into the female reproductive tract at the mid-point of each menstrual cycle and also produce the female hormones oestrogen and progesterone.
Professor Mason believes it might one day be possible to take a small clump of cells from a woman before the menopause and grow new ovaries.
He said: "I certainly believe that if the cells were taken from a woman in her twenties you could grow a new set of ovaries that could later replace her existing ovaries.
"Our goal is to make people healthy through their lifespan and have people playing soccer with their great grandchildren.
"I think this research is moving so fast it is a real possibility and I cannot see any major roadblocks."
Professor Mason, whose work was presented to the American Society for Reproductive Medicine in Utah, removed the ovaries of 10 mice that were 12 months old and had gone through oestropause, a transition similar to the human menopause.
He replaced these with ovaries taken from 60-day old mice - roughly equivalent to people in their early twenties in comparable ageing.
Four months later, he tested the immune systems and metabolisms of the 10 mice and found their systems were similar to those of younger mice.
He and his team also discovered mice transplanted with young ovaries in middle age live about 40 per cent longer than their peers, and have healthier looking hearts.
When the hormone producing cells were removed from the young ovaries before transplantation into older mice, the same benefits were seen.
He thinks other cells inside the ovary might be responsible for the rejuvenation.
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