Featured Research

from universities, journals, and other organizations

Manipulating molecules in heart protects mice on high-fat diets from obesity, affects metabolism

Date:
April 26, 2012
Source:
UT Southwestern Medical Center
Summary:
Researchers have demonstrated for the first time that the heart can regulate energy balance throughout the body, a finding that may point to more effective treatments for obesity, diabetes, and heart disease.

An animal lab. UT Southwestern Medical Center researchers have demonstrated for the first time that the heart can regulate energy balance throughout the body, a finding that may point to more effective treatments for obesity, diabetes, and heart disease.
Credit: © Ragne Kabanova / Fotolia

UT Southwestern Medical Center researchers have demonstrated for the first time that the heart can regulate energy balance throughout the body, a finding that may point to more effective treatments for obesity, diabetes, and heart disease.

Obesity, cardiovascular disease, and diabetes affect tens of millions of people in the U.S., according to the Centers for Disease Control and Prevention.

Using mice fed a high-fat diet, researchers found that manipulating a heart-specific genetic pathway prevents obesity and protects against harmful blood-sugar changes associated with type 2 diabetes. The scientists' findings appear in the April 27 issue of Cell.

"Obesity, diabetes, and coronary artery disease are major causes of human death and disability, and they are all connected to metabolism. This is the first demonstration that the heart can regulate systemic metabolism, which we think opens up a whole new area of investigation," said Dr. Eric Olson, chairman of molecular biology at UT Southwestern and senior author of the study. Lead author of the Cell paper is Dr. Chad Grueter, a postdoctoral researcher in molecular biology.

Their study used genetically altered mice and an experimental drug to manipulate levels of two regulatory molecules in the heart. The scientists found that MED13, a crucial part of a gene pathway in the heart, controls whole-body metabolism while miRNA-208a, a heart-specific microRNA, inhibits the action of MED13.

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.

MicroRNAs are small snippets of genetic material once considered of little interest because they do not code for the proteins used in body processes the way larger strands of genetic material do. In recent years, these molecules have emerged as key regulators of disease and stress responses in various tissues. At least 500 microRNAs have been identified.

"Several years ago, our lab focused on this heart-specific microRNA, miR-208a, and then worked with a biotechnology company to develop a drug to inhibit miR-208a. While studying the effects of that drug, we observed that animals treated with the inhibitor seemed to be resistant to high-fat diets but were otherwise healthy," Dr. Olson said. He is one of five co-founders of the biotechnology company, the Colorado-based miRagen Therapeutics Inc., in which UT Southwestern has an equity stake.

The current study builds on that original observation by identifying the role of miR-208a and its target MED13 in regulating systemic metabolism. How this heart-specific microRNA communicates with cells throughout the body will be the subject of future studies, Dr. Grueter said.

This work was supported, in part, by grants from the National Institutes of Health, the Donald W. Reynolds Center for Clinical Cardiovascular Research, the Robert A. Welch Foundation, the Fondation Leducq-Transatlantic of Excellence in Cardiovascular Research Program, and the American Heart Association-Jon Holden DeHaan Foundation. Dr. Grueter received fellowship support from the American Diabetes Association.

Other investigators involved were Brett A. Johnson, a doctoral candidate of molecular biology; Susan DeLeon, graduate student; Lillian Sutherland, senior research scientist; Xiaoxia Qi, research scientist; Dr. Laurent Gautron, instructor of internal medicine; Dr. Joel Elmquist, professor of internal medicine, psychiatry, and pharmacology; Dr. Rhonda Bassel-Duby, professor of molecular biology; and Dr. Eva van Rooij of miRagen Therapeutics.


Story Source:

The above story is based on materials provided by UT Southwestern Medical Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. Chad E. Grueter, Eva van Rooij, Brett A. Johnson, Susan M. DeLeon, Lillian B. Sutherland, Xiaoxia Qi, Laurent Gautron, Joel K. Elmquist, Rhonda Bassel-Duby, Eric N. Olson. A Cardiac MicroRNA Governs Systemic Energy Homeostasis by Regulation of MED13. Cell, 2012; 149 (3): 671 DOI: 10.1016/j.cell.2012.03.029

Cite This Page:

UT Southwestern Medical Center. "Manipulating molecules in heart protects mice on high-fat diets from obesity, affects metabolism." ScienceDaily. ScienceDaily, 26 April 2012. <www.sciencedaily.com/releases/2012/04/120426135010.htm>.
UT Southwestern Medical Center. (2012, April 26). Manipulating molecules in heart protects mice on high-fat diets from obesity, affects metabolism. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2012/04/120426135010.htm
UT Southwestern Medical Center. "Manipulating molecules in heart protects mice on high-fat diets from obesity, affects metabolism." ScienceDaily. www.sciencedaily.com/releases/2012/04/120426135010.htm (accessed October 21, 2014).

Share This



More Health & Medicine News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

CDC Revamps Ebola Guidelines After Criticism

CDC Revamps Ebola Guidelines After Criticism

Newsy (Oct. 21, 2014) — The Centers for Disease Control and Prevention have issued new protocols for healthcare workers interacting with Ebola patients. Video provided by Newsy
Powered by NewsLook.com
WHO: Ebola Vaccine Trials to Start a in January

WHO: Ebola Vaccine Trials to Start a in January

AP (Oct. 21, 2014) — Tens of thousands of doses of experimental Ebola vaccines could be available for "real-world" testing in West Africa as soon as January as long as they are deemed safe in soon to start trials, the World Health Organization said Tuesday. (Oct. 21) Video provided by AP
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) — A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
CDC Issues New Ebola Guidelines for Health Workers

CDC Issues New Ebola Guidelines for Health Workers

Reuters - US Online Video (Oct. 21, 2014) — The U.S. Centers for Disease Control and Prevention has set up new guidelines for health workers taking care of patients infected with Ebola. Linda So reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins