A Mammalian Longevity Gene?

Researchers find the first evidence that a sirtuin gene prolongs life in mice.

Feb 23, 2012
Edyta Zielinska

FLICKR, NEWTOWN GRAFITTI

In 2001, researchers showed that a sirtuin protein—associated with the cellular stress response and metabolism—was essential for slowing aging in yeast. Now, researchers at Bar-Ilan University in Ramat-Gan, Israel, found that a different member of the sirtuin family may stall death in mice, suggesting sirtuins may also be significant players in mammalian aging.

A couple of years ago, sirtuin 1 (SIRT1) became the focus of attention in aging research because it was the gene that most closely resembled the yeast gene linked to longevity. In 2008, pharmaceutical giant GlaxoSmithKline paid $270 million for a biotech company that was searching for compounds that activated SIRT1, according to Nature. But evidence for SIRT1’s role in expanding lifespan in humans has been hard to come by, and research showing its longevity effects in fruit flies has been questioned.

Instead, researchers at Bar-Ilan looked turned their focus to sirtuin 6 (SIRT6), which in 2006 was shown to speed death in mice lacking the gene. Here they showed that, at least in male mice, overexpression of the SIRT6 extended lifespan by nearly 16 percent. However, other researchers question whether the increase in lifespan is really due to improved longevity, which is associated with improved memory and mobility, or rather a result of anti-cancer or improved metabolic effects, reported Nature.