Most of us by now may be aware that brown fat apparently burns calories and helps treat obesity. Now, scientists from The Ohio State University Medical Center have uncovered a biological switch that transforms the energy storing white fat into energy burning brown fat. The revelations will aid in developing new avenues for treating obesity.
The outcomes show that this conversion is seemingly because the nerve and biochemical pathway gets activated and forms white fat cells. This pathway known as the hypothalamic-adipocyte axis, also introduces brown-fat like cells within the collection of white fat. The white-to-brown fat transition appears to take place when animals are kept in enriched surroundings where there are many societal and physical difficulties.
“One of the holy grails of obesity therapy is to understand how to switch white fat to brown fat, and this study describes a new way to do exactly that,” commented research leader and researcher Dr. Matthew J During, professor of neuroscience, of neurological surgery and of molecular virology, immunology and medical genetics.
The findings suggest that by enhancing lifestyles and pharmacologically activating the brain-fat pathway, this transformation can be made possible. Until now, exposing the body to chronic cold has been the only way of inducing brown fat. The team has showed that animals surviving in an enriched environment supposedly tend to be thinner and show resistance to diet-induced obesity even when huge amounts of food are present.
As a part of research, 15-20 mice were kept in big containers along with running wheels, tunnels, huts, wood toys, a maze, and nesting material as well as unlimited food and water. The control group of mice was put in smaller and normal containers without toys but there was unlimited food and water. As per the results, enriched animals presumably showed a around 49% decrease in abdominal white fat mass than controls. Exercising by means of running in a wheel alone did not seem to result in alterations in bodily constituents and metabolism of enriched animals.
Among those who consumed a high fat diet, enriched animals seemed to put on 29% less weight than control mice and also remained trim. They also did not appear to show changes in food intake. This group also apparently had a higher temperature which implied that more energy and not repressed appetite was giving them the resistance to obesity.
Briefly, During explained that an enriched environment instigates production of a protein called brain-derived neurotrophic factor (BDNF) found in the hypothalamus. The latter is known to help regulate food intake and maintain energy balance. High levels of BDNF accelerate sympathetic nervous signals to bodily white fat masses. These genes specific for brown fat like Prdm16 and Ucp1 are activated by these signals. They also hold back the white-fat gene such as Resn. If BDNF is impeded then it seems to invert the browning effect.
This analysis essentially puts forth that environmental enrichment could have anti-obesity influences which presents a transformation from white fat to brown fat. This is possibly due to a central mechanism called the hypothalamic-sympathoneural-adipocyte axis. Environmental enrichment triggers the hypothalamus to produce the protein BDNF, which increases the sympathetic nerve output to white fat. This causes the white fat to become brown fat that burns the stored energy.
Furthermore, the team is stepping towards recognizing which constituents of environmental enrichment like sensory, cognitive, motor or social stimulation are essential for the browning effect. The findings are published in the September issue of the journal Cell Metabolism.