Monday, October 20, 2014
In obesity, some of the pathways that are involved in fat metabolism are affected. In a recent study researchers have found that upon exposure to cold climate, the inactive white fat from the belly and thighs gets converted to beige fat which burns fat. They also found that this conversion is disrupted in obese individuals.
Generally, the brown adipose tissue (BAT) in the body is known to burn fat and glucose for heat. The white adipose tissue (WAT), in contrast, is inactive, but could burn fat if it adopts certain BAT characteristics. The tissue created in the process is called beige fat.
Published in the Endocrine Society's Journal of Clinical Endocrinology & Metabolism, the study evaluated belly fat tissue samples from 55 people to see if the tissue samples taken in winter showed more evidence of browning activity than those taken in summer. The researchers also took thigh fat tissue samples from 16 people after they held an ice pack on the skin for 30 minutes. They then checked the tissue samples for specific genetic markers found in brown or beige fat.
The belly fat samples taken in winter had higher levels of two genetic markers of beige fat than the summertime samples. Similarly, in the thigh tissue samples, the researchers observed high levels of three beige fat genetic markers.
Additionally, the researchers analysed the belly fat samples to investigate if there was a variation in the response among lean and obese subjects (those having a body mass index >30kg/m2). They found that the seasonal fat browning effect was blunted in obese people.
Speaking about the results of the study, the researchers said, “We wanted to investigate whether human adults had the ability to transform some white fat deposits into beige fat when they were exposed to cold. Our findings indicate inflammation can hinder the conversion of white to beige fat. When we analyzed tissue samples in the lab, we found that exposing white fat to macrophage cells from the immune system inhibited the transformation."
The climate-induced browning of inactive fat tissue indeed spells good news. In an excellent defence mechanism, the newly formed beige fat can help in burning extra calories rather than saving them as additional fat tissue.
For study details:-Click Here!