Simulating the effects of cold stress will help you lose weight
Two groups of scientists independently identified molecular mechanisms, the launch of which simulates the effects of cold stress and causes the body to burn more calories.
Researchers at the University of California at San Francisco, led by Dr. Ajay Chawla, identified two signaling molecules that, under the influence of cold, trigger the transformation of white fat cells into brown fat cells, which are actively cleaved with the release of thermal energy.
In their earlier work, the authors found that exposure to low temperature activates certain immune mechanisms, including the production of interleukin-4 in adipose tissue. Further study of this issue in experiments on mice showed that in addition to the production of interleukin-4, immune cells of adipose tissue also produce interleukin-11 in response to cold. Both signaling molecules attract macrophages synthesizing catecholamines into adipose tissue, and these molecules, in turn, trigger the conversion of white fat into brown.
The introduction of interleukin-4 into the adipose tissue of mice also increased the amount of brown fat in the body. On the other hand, blocking the activity of this cytokine suppressed the production of brown fat, reduced the amount of energy burned by the body and, accordingly, the ability to maintain normal body temperature at low ambient temperature.
It is known that prolonged exposure to the cold on the background of starvation leads to a strong decrease in body weight. Researchers believe that medical manipulations over the mechanism they have uncovered can be used to start the process of burning excess fats at a comfortable temperature for life. However, the ability of the human body to produce and burn brown fat has been studied very little and the development of such therapeutic approaches requires additional research.
At the same time, a group of scientists from the University of Texas, led by Professor Feng Liu, demonstrated that a similar effect can be achieved by activating the growth hormone receptor-linked protein-10 (Grb10), which is a switch of the signaling mechanism mediated by the mammalian rapamycin target protein complex-1 (mTORC1). It turned out that this molecular mechanism, in turn, triggers the transformation of white fat into brown.
Grb10 is activated under conditions of cold stress, which causes the body to burn more calories. According to the authors, it is known that in order to maintain harmony and good functionality, the body needs to get rid of excess nutrients. Therefore, interventions that increase the activity of this protein can help in the fight against conditions such as obesity, metabolic syndrome and type 2 diabetes.
Moreover, the mTORC1-mediated signaling mechanism is involved in the processes of aging, as well as the development of cardiovascular diseases and cancer. Therefore, the data obtained by the authors can be very useful for researchers working in related fields.
Articles by Yifu Qiu et al. Eosinophils and Type 2 Cytokine Signaling in Macrophages Orchestrate Development of Functional Beige Fat and Meilian Liu et al. Grb10 Promotes Lipolysis and Thermogenesis by Phosphorylation-Dependent Feedback Inhibition of mTORC1 published in the journals Cell and Cell Metabolism, respectively.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on University of California, San Francisco: Fat Burning Triggered by Cold Weather May Suggest New Weight Loss Strategy and University of Texas: Team finds on-off switch to burning stored fat.
10.06.2014