Free Radicals Crucial To Appetite Suppression

Now whatcha gonna do?

Obesity is growing at alarming rates worldwide, and the biggest culprit is overeating. In a study of brain circuits that control hunger and satiety, Yale School of Medicine researchers have found that molecular mechanisms controlling free radicals - molecules tied to aging and tissue damage - are at the heart of increased appetite in diet-induced obesity.

Published in the advanced online issue of Nature Medicine, the study found that elevating free radical levels in the hypothalamus directly or indirectly suppresses appetite in obese mice by activating satiety-promoting melanocortin neurons. Free radicals, however, are also thought to drive the aging process.

"It's a catch-22," said senior author Tamas Horvath, the Jean and David W. Wallace Professor of Biomedical Research, chair of comparative medicine and director of the Yale Program on Integrative Cell Signaling and Neurobiology of Metabolism. "On one hand, you must have these critical signaling molecules to stop eating. On the other hand, if exposed to them chronically, free radicals damage cells and promote aging."

Oops.