Brown fat: the study continues
Currently, the so-called brown fat, whose cells, unlike white fat cells, do not accumulate lipids, but burn them with the release of heat, is a popular object of research devoted to the search for new methods to combat obesity and diabetes mellitus.
Researchers in the laboratory of Dr. Patrick Seale, part of the Perelman School of Medicine at the University of Pennsylvania, have devoted their work to the study of proteins that control the development, differentiation and functioning of fat cells. As part of their latest work, they discovered that a protein switch known as early B cell factor-2 (Ebf2) determines the direction of differentiation of fat progenitor cells into white or brown fat cells.
The authors demonstrated that Ebf2 regulates the binding activity of the PPAR-gamma protein, which directs cell differentiation and is a target of antidiabetic drugs. Ebf2 affects the ability of PPAR-gamma to determine the right direction of differentiation of adipose tissue progenitor cells. Apparently, this is due to a change in the configuration of epigenetic labels in the PPAR-gamma binding zones.
A genome-wide comparison of PPAR-gamma binding zones on the DNA of white and brown fat cells showed that binding sites specific to brown fat have regions that recognize the Ebf2 transcription factor, the strong expression of which is characteristic only of brown fat cells.
The study of the formation of adipose tissue in mouse embryos without the Ebf2 gene showed that in the localization typical for brown fat (along the upper half of the spine and in the direction of the shoulders) in such animals, white fat was formed, which indicates the impossibility of differentiation of progenitor cells into brown fat cells in the absence of Ebf2.
Studies conducted in recent years using the positron emission tomography method to assess the level of glucose uptake by different tissues have shown that the amount of brown fat in humans is negatively correlated with body mass index and age. This indicates that brown fat plays an important role in the formation of human metabolism, and confirms the opinion that starting the conversion of white fat into brown can be a new effective method of combating obesity by burning excess lipids stored by the body.
According to the authors, Ebf2 is the earliest known protein involved in the development and differentiation of brown fat cells. To date, it is not a target available for pharmacological action, however, it is possible that any of the proteins interacting with it can act as a target.
The article by Sona Rajakumari et al. EBF2 Determines and Maintains Brown Adipocyte Identity is published in the journal Cell Metabolism.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the University of Pennsylvania:
Knowing How Brown Fat Cells Develop May Help Fight Obesity.
18.03.2013