New evidence links sirtuins and life extension
Ever since he first discovered the lifespan-extending effects of proteins called sirtuins 15 years ago, MIT Professor Leonard Guarente has been accumulating evidence to demonstrate a link between sirtuins and the effects of calorie restriction on lifespan.For decades, it has been known that cutting normal calorie consumption by 30 to 40 percent can boost lifespan and improve overall health in animals such as worms and mice. Guarente believes that those effects are controlled by sirtuins — proteins that keep cells alive and healthy in the face of stress by coordinating a variety of hormonal networks, regulatory proteins and other genes.In his latest work, published yesterday in the journal Genes and Development, Guarente adds to his case by reporting that sirtuins bring about the effects of calorie restriction on a brain system, known as the somatotropic signaling axis, that controls growth and influences lifespan length.“This puts SIRT1 at a nexus connecting...