A new type of adipose tissue - beige fat. Its cells resemble cells of brown fat and also burn the excess lipids to form the heat, but different set of essential biochemical and genetic traits.
There are two types of adipose tissue - white and brown. White fat accumulates lipids, brown - burning and thus produces heat. Not so long ago thought that brown fat only in animals and babies, and adults who do not have it. Then he found in adults, and therefore had the idea that brown fat can be used as an anti-obesity: fat burning brown cells could reduce deposits of fat in the white cells.
Researchers at the Cancer Institute Dana - Farber (USA) was added to the two third fats, called them "beige" (or "light brown"). For the first time scientists have stumbled upon this type of fatty tissue in 2008. In his new article in the journal Cell, they just explain that beige fat - this is quite an independent type, not a kind of brown, but as brown fat, it burns lipid reserves accumulated in white adipocytes. In adults, beige subcutaneous fat forms small clusters near the collarbone and along the spine.
Generally speaking, the researchers believe that the brown fat, which opened in adults, is not really brown and beige. Although they are easily confused between these two types of fat cells there are significant differences. Brown cells maintain a constant high level of protein UCP1: it is necessary to effectively metabolize fat mitochondria to generate heat. In the beige cells this protein level is low, although they also contain many mitochondria. But under the influence of some factors - for example, in response to cold - the synthesis of UCP1 in beige fat may increase. In addition, beige cells can stimulate hormone irisinom (who recently appeared in the news, however, because of the brown fat).
Brown and beige, and fats are different in origin. Brown stem cells arise from precursors that are common to them and to the muscle cells. In beige has its own progenitor cells, and they are formed in clusters of white fat. Beige fat can burn lipids with almost the same efficiency as brown. So, if you really adult brown fat really fake, researchers just have to forget about it and do beige, which can also be used for the regulation of metabolism and preventing obesity.
However, it is possible that somewhere a man hiding and this brown fat: it is very difficult to imagine that scientists so long to pay attention to the differences from vsamdelishny, animal brown fat.