Mini molecular targets for obesity

Researchers have discovered that  microRNAs affect how our cells burn fat and sugar – a finding that may have potential for obesity treatment.

Scientists at Virginia Tech and the University of Texas Southwestern Medical Center at Dallas observed that mice on high fat diets were resistant to obesity when two microRNAs were removed from their genome. The study was published in the Proceedings of the National Academy of Science.

MicroRNAs are tiny strands of RNA, once considered little more than scrap DNA, now known to play an important role in regulating how genes shape human health such as in heart disease and diabetes.

“Scientists know the best health solution for obesity involves eating less and exercising more,” Matthew W Hulver, associate professor with the Department of Human Nutrition, Foods and Exercise at Virginia Tech said: “But in cases when people can’t and won’t exercise, if we can identify what is contributing to the regulation of our metabolic circuits, we can target it with a pharmacological solution.”

The scientists isolated mitochondria from liver and skeletal muscle from the genetically modified mice. They observed an increase in oxidation of fatty acids, suggesting that loss of specific microRNAs results in increased energy expenditure.

“We did not know the function of this pair of microRNAs, but were intrigued because they arose from a gene connected with metabolism, and they are expressed in a variety of tissues, such as muscle, fat and liver,” said Eric Olson, senior author of the study.

“When we modified mice so that they were missing these microRNAs, it permitted their cells to burn more energy and have greater obesity resistance than those of their untreated litter mates. This pair of microRNAs seems to function as key regulators of metabolism, suggesting that a drug designed to inhibit them would have a positive effect against obesity,” Olson added.

Olson’s lab has looked into microRNA changes on various disease states, including heart disease and amyotrophic lateral sclerosis.

It is hoped that these findings may represent a magic bullet solution against the worldwide obesity epidemic.

Control of mitochondrial metabolism and systemic energy homeostasis by microRNAs 378 and 378