Anti-Aging Approaches

Marina Bolotnikova in Harvard Magazine:

Decades of research have shown that calorie restriction extends lifespan and delays morbidity in many small, short-lived species: yeast, spiders, and various fish and rodents. In humans, though, the benefits of calorie restriction are still unproven, and probably less straightforward. And how calorie restriction slows the aging process is still not well understood. “The interesting thing about calorie restriction is that we used to think the body was in some way slowing down, maybe in the number of heartbeats or production of free radicals,” says professor of genetics David Sinclair. “But it turns out that’s wrong….When we’re calorie restricting, what we’re really doing is telling the body that now is not the time to go forth and multiply. It’s time to conserve your resources, repair things better, fight free radicals, and repair broken DNA.”

Sinclair believes that a compound found in all living cells, nicotinamide adenine dinucleotide (NAD), could be used to mimic these effects in humans without the starvation or decreased reproductive capacity associated with calorie restriction; his human trials of a therapy that could increase NAD levels are due to begin this month. Meanwhile, a similar compound is already being marketed as a supplement by a health start-up with several distinguished scientists (including three Harvard faculty members) on its advisory board—even though there’s still no evidence that the substance works. Sinclair’s approach is based on a broad view that links diseases of age such as cancer, diabetes, Alzheimer’s, and heart failure to common cellular processes. His lab aims to understand these processes and then use that understanding to develop medical therapies. Underlying the wide-ranging benefits of calorie restriction, Sinclair explains, are sirtuins—a group of seven genes that appear to be very important in regulating the aging process. “These longevity-gene pathways are turned on by changes in lifestyle” such as exercise and calorie restriction, he says.

More here.