Team finds mechanism that regulates production of energy-burning brown fat

March 13, 2013

Joslin scientists have discovered a mechanism that regulates the production of brown fat, a type of fat which plays an important role in heat production and energy metabolism. The findings, which appear in the upcoming issue of Nature, may lead to new therapies that increase BAT formation to treat obesity.

Two types of fat tissue are present in humans and other mammals: (WAT) or white fat, which stores fat; and (BAT) or brown fat, which burns fat to produce heat. Brown fat also metabolizes glucose and fatty acids which is important in diabetes and . Studies suggest that brown fat provides a natural defense against obesity: people with greater quantities of brown fat have lower body weights. This has made brown fat the focus of considerable interest among scientists and pharmaceutical companies looking for ways to treat obesity.

Joslin scientists in the Tseng Laboratory of the Section on Integrative Physiology and Metabolism previously discovered that one type of , BMP-7, plays a key role in the control of brown fat formation and its heat-producing activity, which regulates whole . In the present study, the scientists created a genetically mutant mouse model deficient in type 1A BMP-receptor (BMPR1A), a key receptor for BMP-7 which has been shown to be associated with obesity in .

Mice have two types of BAT: constitutive BAT (cBAT), which develops before birth; and recruitable BAT (rBAT), which is found in WAT and skeletal muscle. Humans may also have two types of BAT.

The mice lacking BMPR1A were born with a deficiency of cBAT. Despite their lack of cBAT, the mutant mice were able to "maintain their body temperature perfectly," says senior author Yu-Hua Tseng, Ph.D., Assistant Professor of Medicine at Harvard Medical School, Principal Faculty of the Harvard Stem Cell Institute and an Investigator in the Section on Integrative Physiology and Metabolism.

The scientists discovered that when cBAT is deficient, cBAT cells send a signal through the sympathetic nervous system to increase production of rBAT within white fat. This study is the first to report this cross-talk between these two types of brown fat. The increased rBAT was sufficient to maintain normal body temperature and also protect against diet-induced obesity: When the control and mutant mice were fed a high-fat diet, the did not gain more weight than the control mice.

Until this study, it was not known why a body needs two types of BAT and how they interact with each other. "These results show us that brown fat is essential for normal functioning. When one type of brown fat is deficient, the body has a sophisticated system for inducing development of the other type of brown fat to maintain body temperature and metabolism," says Dr. Tseng.

Tseng Laboratory scientists are interested in learning more about the function of human brown fat cells, including whether humans have two types of BAT, and understanding how BMP and related factors affect human production. "We would like to translate this research to develop treatments for diabetes and obesity. This new type of therapy would be especially beneficial to individuals who cannot lose weight through diet or have a limited ability to exercise," says Dr. Tseng.

Explore further: Brown adipose tissue beneficial for metabolism and glucose tolerance

Related Stories

Brown adipose tissue beneficial for metabolism and glucose tolerance

December 10, 2012
Joslin Diabetes Center scientists have demonstrated that brown adipose tissue (BAT) has beneficial effects on glucose tolerance, body weight and metabolism. The findings, which may lead to new treatments for diabetes, appear ...

Scientists identify protein that stimulates brown fat to burn calories

May 10, 2012
Scientists have identified a protein which regulates the activation of brown fat in both the brain and the body's tissues. Their research, which was conducted in mice, was published today, Friday 11 May, in the journal Cell.

Calorie-burning brown fat is a potential obesity treatment, researchers say

June 6, 2011
A new study suggests that many adults have large amounts of brown fat, the "good" fat that burns calories to keep us warm, and that it may be possible to make even more of this tissue.

A new candidate pathway for treating visceral obesity

May 6, 2012
Brown seems to be the color of choice when it comes to the types of fat cells in our bodies. Brown fat expends energy, while its counterpart, white fat stores it. The danger in white fat cells, along with the increased risk ...

Recommended for you

New vaccine production could improve flu shot accuracy

July 24, 2017
A new way of producing the seasonal flu vaccine could speed up the process and provide better protection against infection.

Molecular hitchhiker on human protein signals tumors to self-destruct

July 24, 2017
Powerful molecules can hitch rides on a plentiful human protein and signal tumors to self-destruct, a team of Vanderbilt University engineers found.

Researchers develop new method to generate human antibodies

July 24, 2017
An international team of scientists has developed a method to rapidly produce specific human antibodies in the laboratory. The technique, which will be described in a paper to be published July 24 in The Journal of Experimental ...

A sodium surprise: Engineers find unexpected result during cardiac research

July 20, 2017
Irregular heartbeat—or arrhythmia—can have sudden and often fatal consequences. A biomedical engineering team at Washington University in St. Louis examining molecular behavior in cardiac tissue recently made a surprising ...

Want to win at sports? Take a cue from these mighty mice

July 20, 2017
As student athletes hit training fields this summer to gain the competitive edge, a new study shows how the experiences of a tiny mouse can put them on the path to winning.

'Smart' robot technology could give stroke rehab a boost

July 19, 2017
Scientists say they have developed a "smart" robotic harness that might make it easier for people to learn to walk again after a stroke or spinal cord injury.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.