Featured Research

from universities, journals, and other organizations

Genetic switch increases muscle blood supply

Date:
March 1, 2011
Source:
University of Texas Health Science Center at Houston
Summary:
Many people suffer from a devastating condition known as critical limb ischemia that can lead to muscle wasting and even amputation. The disease is linked to the blockage of blood flow to the skeletal muscle and current treatment options include rehabilitative exercise and surgical bypass of blood vessels. New preclinical research suggests there may be a way to restore blood supply in skeletal muscle without traditional intervention.

Genetic enhancement of skeletal muscle blood supply: Turning on a gene switch known as estrogen-related receptor gamma converts fast twitch muscle fibers into slow twitch fibers with a dense supply of blood vessels. The composite image shows blood vessels in green and muscle fibers in red.
Credit: Courtesy of Jamie Simon, Salk Institute for Biological Studies

Many people suffer from a devastating condition known as critical limb ischemia (CLI) that can lead to muscle wasting and even amputation. The disease is linked to the blockage of blood flow to the skeletal muscle and current treatment options include rehabilitative exercise and surgical bypass of blood vessels. New preclinical research suggests there may be a way to restore blood supply in skeletal muscle without traditional intervention.

Scientists at The University of Texas Health Science Center at Houston (UTHealth) and the Salk Institute for Biological Studies announced in the March 2 print issue of the journal Cell Metabolism that they have identified a genetic switch that can increase the number of blood vessels in the skeletal muscle of non-exercising mice.

Skeletal muscle is composed of two types of fibers: slow twitch fibers that inherently have a dense supply of blood vessels and fast twitch fibers that have fewer blood vessels. The researchers used a gene switch known as estrogen-related receptor gamma (ERR gamma) that when activated in fast twitch fibers of mice by genetic engineering, converts these fibers into slow twitch fibers.

"This consequently resulted in a striking increase in muscle blood supply as measured by imaging and angiography," said Vihang Narkar, Ph.D., lead investigator and assistant professor of molecular medicine at the UTHealth Medical School. "These genetically-transformed muscles also acquire other characteristics of slow muscles, such as improved metabolic capacity and fatigue resistance that can be additionally beneficial in resolving muscle vascular disease."

Narkar, whose UTHealth laboratory is in the Center for Diabetes and Obesity Research at the Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, said, "The identification of the estrogen-related receptor gamma vascular switch will open potential therapeutic avenues for treating CLI and other cardiovascular diseases linked to defective blood supply."

Colin Barker, M.D., assistant professor of cardiology at the UTHealth Medical School, said new research is needed to help people with peripheral artery disease, particularly those with the most severe form -- critical limb ischemia. "Poor circulation in the legs can lead to muscle wasting, infections, severe pain and amputation," he said. "Dr. Narkar's work potentially has many useful applications. It is very much in the translational medicine arena."

"Understanding the gene network that specifies high vascular supply to muscle gives us a new and very powerful tool to promote improved muscle performance and the promise of fitness, especially for those who cannot work out," says Ronald M. Evans, Ph.D., senior author, Howard Hughes Medical Institute Investigator and professor in the Salk's Institute's Gene Expression Laboratory. "This is good news for people with heart disease, frailty, peripheral vascular disease and more generally those who have a variety of medical problems where exercise could be helpful but is not possible to achieve."

In 2010, an estimated 2.8 to 3.5 million U.S. citizens suffered from critical limb ischemia, according to a report by THE SAGE GROUP, an independent research and consulting company specializing in peripheral artery disease. CLI risk factors include diabetes, obesity and smoking.

"Exercise is an important part of any intervention strategy to prevent or treat diabetes mellitus and obesity," said Perry Bickel, M.D., associate professor of medicine at the UTHealth Medical School and director of the UTHealth Center for Diabetes and Obesity Research. "Results by Drs. Narkar and Evans support the notion that in the future we may be able to design drugs that produce the benefits of exercise in order to counteract the damage that diabetes and obesity cause to the body, such as blockages of blood vessels."

Narkar and Evans collaborated on a highly-publicized study published in the journal Cell in 2008 in which they used two investigational exercise mimetic drugs -- GW1516 and AICAR -- to increase the endurance of non-exercising mice. These drugs target different genetic switches, namely PPAR delta and AMPK.


Story Source:

The above story is based on materials provided by University of Texas Health Science Center at Houston. Note: Materials may be edited for content and length.


Journal Reference:

  1. Vihang A. Narkar, Weiwei Fan, Michael Downes, Ruth T. Yu, Johan W. Jonker, William A. Alaynick, Ester Banayo, Malith S. Karunasiri, Sabina Lorca, Ronald M. Evans. Exercise and PGC-1α-Independent Synchronization of Type I Muscle Metabolism and Vasculature by ERRγ. Cell Metabolism, Volume 13, Issue 3, 2 March 2011, Pages 283-293 DOI: 10.1016/j.cmet.2011.01.019

Cite This Page:

University of Texas Health Science Center at Houston. "Genetic switch increases muscle blood supply." ScienceDaily. ScienceDaily, 1 March 2011. <www.sciencedaily.com/releases/2011/03/110301142018.htm>.
University of Texas Health Science Center at Houston. (2011, March 1). Genetic switch increases muscle blood supply. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2011/03/110301142018.htm
University of Texas Health Science Center at Houston. "Genetic switch increases muscle blood supply." ScienceDaily. www.sciencedaily.com/releases/2011/03/110301142018.htm (accessed July 24, 2014).

Share This




More Health & Medicine News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. Video provided by Newsy
Powered by NewsLook.com
Condemned Man's US Execution Takes Nearly Two Hours

Condemned Man's US Execution Takes Nearly Two Hours

AFP (July 24, 2014) America's death penalty debate raged Thursday after it took nearly two hours for Arizona to execute a prisoner who lost a Supreme Court battle challenging the experimental lethal drug cocktail. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com
China's Ageing Millions Look Forward to Bleak Future

China's Ageing Millions Look Forward to Bleak Future

AFP (July 24, 2014) China's elderly population is expanding so quickly that children struggle to look after them, pushing them to do something unexpected in Chinese society- move their parents into a nursing home. Duration: 02:07 Video provided by AFP
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:
from the past week

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