Technology :: 'Fountain of youth' enzyme lengthens mouse life

FINALLY, a contender for the elusive fountain of youth: an enzyme found in humans appears to lengthen the life of mice.

Researchers hoping to slow the march of age were dealt a blow in 2010, when signs that an enzyme called sirtuin 2 extended the life of worms were shown to be false due to flawed experimental design.

Mammals have seven types of sirtuin, so Haim Cohen and Yariv Kanfi at Bar-Ilan University in Ramat Gan, Israel, turned to sirtuin 6 instead. They compared mice genetically engineered to have increased levels of SIRT6 with normal mice, engineering the mice in two different ways to control for genetic influences.

Male mice from both strains lived 15 per cent longer than normal mice or females. Older modified male mice metabolised sugar faster than normal mice and females, suggesting that SIRT6 might extend life by protecting against metabolic disorders such as diabetes.

Why SIRT6 didn't affect females is a puzzle, but may be related to differences in genes that regulate ageing in males and females.