Obesity: Scientists identify a protein that promotes the burning of body fat

A discovery has been made by Scientists of a protein that can promote the burning of body fat, leading to new ways of tackling obesity.

Injecting mice with BMP7 protein kept their levels of normal white fat cells constant whilst increasing their production of “good” brown fat cells.

“White fat cells store energy and contribute to obesity, and brown fat cells burn calories to generate body heat”.

Every person is born with a good amount of brown fat cells which are usually lost after infancy. The amount of energy a person burns would therefore increase with the reintroduction of brown fat.

Yu-Hua Tseng’s team at the Joslin Diabetes Centre at Harvard Medical School identified a protein calls BMP7 which promotes the creation of brown fat, whilst looking at factors which determine the amount of different types of fat cell in the body. Without BMP7 the amount of brown fat in mice ran low. The artificially administered protein boosted the amount of brown fat and the white fat remained unchanged.

“As we learn more about the controls of brown fat development, medical interventions to increase energy expenditure by brown fat inducing agents, such as BMP7, may provide hope to these individuals in losing weight and preventing the metabolic disorders associated with obesity,” said Tseng.

A separate study at the Dana-Farber Cancer Institute in Massachusetts which was led by Bruce Spiegelman, found that brown fat cells can be made from the same precursor tissue that normally produces muscle cells. It was found that a molecular switch called PRDM16 regulates the creation of brown fat from immature muscle cells. Turning off the switch in the lab converted brown fat in mice into muscle cells.

Both studies are published in this week’s issue of the journal Nature.

“Brown fat can increase energy expenditure and protect against obesity,” Spiegelman writes. “The epidemic of obesity, closely associated with increases in diabetes, hypertension, hyperlipidemia, cancer and other disorders, has propelled a major interest in adipose cells and tissues.”

According to Spiegelman the next step is to find specific drugs and techniques that could help the body make more brown fat cells or else genetically engineer white fat cells to turn brown.

Barbara Cannon and Jan Nedergaard, biologists at Stockholm University said in an accompanying commentary in Nature, “Insights into the developmental origin of brown fat cells are of particular interest because of the ability of these cells to burn fat. But, as is often the case in science, new questions follow new insights.”

They add that a thorough understanding of the function and creation of brown fat cells could take us closer to the “ultimate goal of promoting the brown fat lineage as a potential way of counteracting obesity.”