Researchers at UT Southwestern Medical Center in Dallas have shown that the heart can regulate energy balance throughout the body. The breakthrough could pave the way for better treatments for obesity, diabetes, and heart disease.
The research, which will be presented in the April 27 issue of Cell, investigated genetically modified mice and an experimental drug to manipulate levels of two regulatory molecules in the heart: MED13 and miRNA-208a. The mice in the study were fed a high-fat diet but did not become obese as a result of the manipulation of the heart-specific genetic pathway. The genetic alteration also protected the mice from blood-sugar changes linked to type-2 diabetes.
In the research, MED13 was shown to control whole-body metabolism and miRNA-208a, a heart-specific microRNA, was shown to inhibit the action of MED13.
As the press release explains:
Mice with MED13 levels that were increased either genetically or by a drug were lean and showed an increase in energy expenditure, the researchers said. In contrast, mice genetically engineered to lack MED13 in the heart showed increased susceptibility to diet-induced obesity. These mice also had aberrant blood-sugar metabolism and other changes similar to those of a group of conditions called metabolic syndrome, which is linked to the development of coronary artery disease, stroke, and type 2 diabetes.
The biotechnology company miRagen (Boulder, CO) developed the drug to inhibit miR-208a in the study.
Image from miRagen’s website: What are miRNAs?