(PhysOrg.com) -- A new paper from MIT biology professor Leonard
Guarente strengthens the link between longevity proteins called
sirtuins and the lifespan-extending effects of calorie
restriction. 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 Dec. 15 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 the
effects of diet and the somatropic signaling axis," says
Guarente. "This is a major shot across the bow tha