Washington, Oct 10 Resveratrol, a molecule found in red grapes, has been shown to improve diabetes when delivered orally to rodents, but it is only now that scientists have discovered how it works in the body.

A new study shows that the brain plays a key role in mediating resveratrol's anti-diabetic actions, potentially paving the way for orally-delivered diabetes medications that target the brain.

Resveratrol activates sirtuins, a class of proteins that are thought to underlie many of the beneficial effects of restricting calories.

Previous studies in mice have provided compelling evidence that when sirtuins are activated by resveratrol, diabetes is improved. Sirtuin activators are now being tested on humans as anti-diabetic compounds.

Sirtuins are expressed virtually everywhere throughout the body and until now, little has been known about what tissues mediate resveratrol's beneficial effects.

Knowing where in the body the beneficial effects of activated sirtuins are mediated could help in the development of more effective targeted diabetes medications.

"We know that sirtuins are expressed in parts of the brain known to govern glucose metabolism, so we hypothesized that the brain could be mediating resveratrol's anti-diabetic actions," said Roberto Coppari, University of Texas Southwestern Medical Centre (UTSMC) and study co-author.

"To test the hypothesis, we assessed the metabolic consequences of delivering resveratrol directly into the brain of diabetic mice. We found that resveratrol did activate sirtuins in the brain of these mice which resulted in improving their high levels of blood sugar and insulin."

"These findings may lead to new strategies in the fight against type 2 diabetes," a Endocrine Society release quoted Coppari as saying.

The study will appear in the December issue of Endocrinology. (IANS)