May 12, 2011

Scientists Explain Lifespan

(Ivanhoe Newswire) -- Scientists have discovered a new role for a biological pathway that not only signals the body's metabolic response to nutritional changes but also affects lifespan.

The researchers conducted the study on Caenorhabditis elegans (nematodes). Dietary restriction is a way to extend lifespan and postpone age-related diseases in many species including yeast, worms, flies and rodents. However, researchers have been unclear about the molecular signals involved until this study.

The molecules identified in the study are N-acylethanolamines (NAEs). The scientists found that NAE abundance in the worm is reduced during periods of dietary restriction and that NAE deficiency in the presence of abundant food is enough to extend the animal's lifespan.

"It is well known that if you put C. elegans on a restricted diet, you can extend its lifespan by 40 to 50 percent," Matthew Gill, Ph.D., an assistant professor in the Scripps Research Department of Metabolism and Aging, was quoted as saying. "However, we were amazed to see that if you add back just one of these NAE molecules, eicosapentaenoyl ethanolamide, it completely abrogates the lifespan extension."

Researchers say this particular NAE is similar to endocannabinoids in mammals, which regulate many different physiological processes including nutrient intake, energy balance, inflammation and neuronal function. "The identification of other components of a novel endocannabinoid system in the worm now brings a new model system to the many researchers studying NAE and endocannabinoid physiology," said Gill.

Dr. Gill says the study's results could help shape future drug development efforts to influence aging and age-related disease.

SOURCE: Nature, May 2011