Reduced metabolic efficiency prevents obesity
In experiments on mice, scientists at the Pennington Biomedical Research Center, working under the direction of Dr. Leslie Kozak, found that inactivation of a pair of genes involved in fat burning increases energy consumption and prevents the development of diet-induced obesity.
Humans and other warm-blooded animals need to continuously break down fats to maintain body temperature. Traditionally, it is believed that people with a high thermogenic potential – a greater ability to generate heat when splitting fats – are less likely to be obese. Bodybuilders and people on a diet for weight loss often use drugs with thermogenic components.
Theoretically, a decrease in thermogenesis should increase the chances of developing obesity, but the authors demonstrated the opposite. They inactivated two thermogenic genes Ucp1 (mitochondrial uncoupling protein) and Gdm (glycerol-3-phosphate dehydrogenase) in mice, after which they fed the animals with a fat-rich feed, while maintaining the ambient temperature at 20 °C.
To the surprise of the researchers, the mice, instead of getting strenuously fat, acquired resistance to obesity. The reason for this was the transition of animals to a kind of backup heat generator. In the absence of Ucp1 and Gdm genes providing efficient heat production, animal fat cells activated alternative and less effective mechanisms of fat breakdown. In this case, inefficiency played a positive role, because to warm the body, the mice had to burn more calories.
After 10 weeks, the temperature of the animals was raised to 28 degrees, but they continued to use the same alternative mechanisms of fat splitting, which indicated the adaptation of the body.
The authors believe that their unexpected discovery provides new opportunities in the development of methods for treating obesity.
Article by Anunciado-Koza et al. "Inactivation of UCP1 and the Glycerol Phosphate Cycle Synergistically Increases Energy Expenditure to Resist Diet-induced Obesity" published in the Journal of Biological Chemistry.
Portal "Eternal youth" http://vechnayamolodost.ru / based on ScienceDaily – Making Metabolism More Ineffective Can Reduce Obesity
06.10.2008