Dietary Supplement Makes Old Mice Youthful, Hinting at Use in Humans
For years scientists have been trying to conquer the aging process, but after a few setbacks and stumbles, it seems they have come the closest they have ever got.
In the latest advance, biologists reported that a molecule already sold by supplement makers restored youthfulness to blood vessels in 20 month-old mice, an age comparable to 70 years in people. This research supports the idea that boosting certain genes and molecules that fade with age could help people functionally step into their 80s.
“I think it’s quite an important paper,” explained Dr Eric Verdin, of the California-based Buck Institute for Research on Aging. “It’s probably not the magic pill everyone is looking for, but it’s one more brick in our efforts to understand aging and healthspan.”
However, some have been skeptical, calling the advance “incremental.” David Harrison of the Jackson Lab, an expert on the molecular mechanisms of aging, added, “It’s hard to tell how significant any contribution is until it has been replicated and extended,” by other labs.
The study, published in Cell, discovered that boosting mice’s levels of the naturally occurring molecule NMN, which humans also have, increased levels of another called NAD+. In turn, this raised levels of anti-aging enzyme, SIRT1, which has been the focus of close to 30 years of research.
After two months passed, more blood vessels sprouted in the old mice’s muscles. The density of the smallest vessels – capillaries – became comparable to that of young mice. As a result, blood flow increased, and the animals’ endurance, measured by how long they could run on a treadmill before becoming exhausted, was 56% to 80% greater than that of untreated old mice: 1,400 feet compared to 780 feet.
In addition, new blood vessels could be very beneficial, largely because they support the growth of tumours, which is why anti-angiogenesis molecules have become cancer drugs. The scientists found no excess cancer in the mice given NMR, but “more study is warranted,” they concluded.