Brown fat plays an important role in diabetes and metabolism because of its ability to metabolize glucose and fatty acids….
According to other studies, it may even serve as a natural defense and treatment of obesity. A new published study shows a mechanism that regulates the production of brown fat.
Body morphogenic protein, BMP-7, has been shown previously to control brown fat formation. This new study used genetically mutant mice with a type 1A BMP receptor (BMPR1A) deficiency, a key receptor for BMP-7 that is linked to obesity in humans.
There are two types of brown adipose tissue (BAT) in mice: constitutive BAT (cBAT), and recruitable BAT (rBAT). The cBAT develops prior to birth and the rBAT is found in white adipose tissue and skeletal muscle. A deficiency of cBAT was detected in the mice lacking BMPR1A. Even though the mice were deficient in cBAT, they still were able to maintain their body temperature. Researchers discovered that the deficiency in cBAT led to signals being sent to the sympathetic nervous system to produce more rBAT in white fat. Increased rBAT production was effective in maintaining normal body temperature and was shown to protect against obesity. When the mutant and control mice were fed a high fat diet, the mutant mice maintained their weight compared to the control mice.
The mechanism revealed is the body’s ability to maintain body temperature and metabolism by inducing the development in other types of brown fat when one type of brown fat is lacking. Dr. Yua Hua Tseng says, "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." This study confirmed the importance of why the body needs two different types of brown fat and how they signal each other in the body. This information could be key in finding a treatment for obesity in the future.
Brown-fat paucity due to impaired BMP signalling induces compensatory browning of white fat. Nature, March, 2013; DOI: 10.1038/nature11943.