Signaling System in Brain Discovered to Help Control Weight, Food Intake

Researchers have identified an important signaling system in the brain that helps to control food intake and body weight and that could lead to the development of new drugs to fight obesity. A team from the University of Washington reports in Nature that the melanocortin-4 (MC4) receptor in rats acts as a mediator for leptin, a hormone known to reduce body weight by acting on the central nervous system.

The team found that rats who had their MC4 receptors chemically blocked were unaffected by treatment with leptin, while those with intact receptors ate less food and lost weight when receiving the same amount of leptin. The study suggests why some people are resistant to the effects of the hormone.