A member of the sirtuin family of proteins, SIRT6, has been shown to extend lifespans in mammals. Researchers studying the aging process have long been intrigued by the sirtuin genes and their associated proteins. Recent results published in the journal Nature suggest that the overexpression of this one gene can lengthen lifespan in male mice by up to 15.8%.
SIRT1 has been in the spotlight for years, since it was also closely related to the longevity-linked yeast gene. Some researchers speculated that SIRT1 could boost lifespan in mammals, and that it was the target of resveratrol, a compound found in red wine that’s been linked to a variety of health benefits.
Until now, SIRT1 has not affected longevity in mammals, although its expression is associated with a healthier metabolism in mice fed a high-fat diet. Haim Cohen, a molecular biologist at Bar-Ilan University in Ramat-Gan, Israel, studied the SIRT6 gene.
In 2006, it was reported that mice missing the SIRT6 gene seemed to age more quickly. When mice had higher levels of SIRT6, longevity in females was unaffected, but the median lifespan of male mice rose by 14.5%. The maximum lifespan rose by 15.8%.
The strain of mice used in the lab experiments are particularly prone to tumors, especially in males. The longer lifespan could be a result of an anti-cancer effect of SIRT6 rather than a direct effect on aging.
It is not yet known why sirtuin levels affect males and females differently.
Reference: “Sirtuin protein linked to longevity in mammals” by Heidi Ledford, 22 February 2012, Nature.