How brain stimulates body to burn bad fat

A team of Australian researchers has uncovered the action of two naturally occurring hormones along with brain signals that assist in the shedding of excess fat.

Researchers from Monash University unravelled a molecular mechanism that depends on the combined action of two hormones - leptin, an appetite suppressant generated in fat cells, and insulin, produced in the pancreas.

The findings show that the two hormones act in concert on a group of neurons in the brain to stimulate the burning of body fat via the nervous system.

It gives new insights into how the brain regulates body fat and may lead to more effective ways to lose weight and prevent obesity by promoting the conversion of "bad" white fat to "good" brown fat.

"These hormones give the brain a comprehensive picture of the fatness of the body," said lead researcher professor Tony Tiganis.

Because leptin is produced by fat cells, it measures the level of existing fat reserves - the more fat, the more leptin. Whereas insulin provides a measure of future fat reserves because glucose levels rise when we eat.

The research team discovered that leptin and insulin interact with neurons in the brain's hypothalamus, causing them to send signals through the nervous system promoting the conversion of white fat into brown fat.

This leads to burning off of excess fat. Professor Tiganis said this fundamental process normally serves to maintain body weight but in diet-induced obesity, this mechanism goes awry.

"Eventually, we think we may be able to help people lose weight by targeting these two enzymes. Turning white fat into brown fat is a very exciting new approach to developing weight-loss agents," professor Tiganis concluded