Harmful (and unnecessary?) protein

A protein has been found that prevents brown fat from producing heat

Anna Stavina, XX2 century, based on Medical News Today: Specific protein may cause obesity by interfering with brown fat

Adipose tissue is not always a bad thing. The so-called "brown fat", as well as "beige" (both of them are varieties of adipose tissue), plays an important role in metabolism. These tissues generate energy and help the body adapt to temperature changes. In a new study, it was found that there is a protein that can provoke the further development of obesity by suppressing the energy function of beige and brown fat.

Our body stores energy in the form of fat. Adipose tissue is usually divided into two types – white and brown fat. The third type, beige fat, is formed from white adipose tissue when it is activated by a certain stimulus.

The functions of white and brown fat differ. In white fat cells, energy is stored in the form of triglycerides, compounds often found in the blood. Elevated triglyceride levels are associated with an increased risk of developing cardiovascular diseases and type 2 diabetes. Brown fat, on the contrary, consumes energy by producing heat. This process is called "thermogenesis".

There are also structural differences between these types of adipose tissue. In the cells of brown and beige adipose tissue, there are more mitochondria, cellular "power plants" that produce energy. In white adipose tissue, there are fewer not only mitochondria, but also blood vessels.

Beige and brown fat are considered more "useful" than white. Previous studies have shown that these tissues are able to reduce the severity of metabolic diseases and obesity in mice, and work involving human volunteers has revealed a link between these types of fat and thinness.

A new study, the results of which are published in the publication Diabetes (Patil et al., Id1 Promotes Obesity by Suppressing Brown Adipose Thermogenesis and White Adipose Browning) has demonstrated that high concentrations of a certain protein can inhibit the energy production process in brown and beige fat. This protein is called Id1, and it was previously found that it is also associated with prostate cancer.

In the course of the new work, Dr. Satya Ande, a molecular biologist from the Georgia Cancer Center and the Medical College of Georgia in At the University of Augusta (Medical College of Georgia at Augusta University), and her colleagues developed a line of genetically modified mice whose fat cells produced large amounts of Id1. Then some of the animals were transferred to a high-fat diet, while others were given regular food. The control group, consisting of ordinary mice, was fed the same way – some animals received fatty food, while others received normal.

The body weight of mice from the experimental group was significantly higher than the body weight of mice from the control group. It is important that even those animals that received regular food, with an excess of Id1, gained more than mice from the control group on the same diet.

The study showed that Id1 interacts with brown adipose tissue in large quantities, suppressing its work. In particular, it inhibits the activity of the key transcription factor PGC-1a, which regulates thermogenesis by interacting with the unique protein Ucp1. The latter, in turn, helps brown adipose tissue to consume energy more efficiently by generating heat.

In addition, the scientists found that Id1 suppresses the work of another transcription factor, Ebf2, which promotes the transformation of white adipose tissue into beige. Researchers have demonstrated that removing the Id1 protein increases the expression of a gene associated with beige adipose tissue in response to contact with cold. The authors also suggested that the Id1 protein, apparently, is not needed for the normal functioning of the body - at least in mice.

According to the researchers, the results of the work indicate that Id1 is a risk factor for the development of obesity and diabetes mellitus, and can be considered as a therapeutic target in the treatment of these diseases.

Portal "Eternal youth" http://vechnayamolodost.ru  19.04.2017