Featured Research

from universities, journals, and other organizations

Researchers Find Genetic Switch That Explains Effect Of Exercise On Muscles

Date:
August 24, 1998
Source:
University Of Texas Southwestern Medical Center At Dallas
Summary:
The creation of a drug that would mimic some of the health-promoting benefits of regular exercise could be possible because UT Southwestern Medical Center at Dallas researchers have found a genetic switch that tells muscles how to behave.

DALLAS, Texas, Aug. 20, 1998--The creation of a drug that would mimic some of the health-promoting benefits of regular exercise could be possible because UT Southwestern Medical Center at Dallas researchers have found a genetic switch that tells muscles how to behave.

UT Southwestern scientists have found the molecular pathway that tells muscle fiber to be either the fast strength muscle seen in weight lifters or the slow endurance muscle developed by aerobic enthusiasts. Using cultured muscle cells, investigators, led by Dr. R. Sanders Williams, chief of cardiology and director of the Frank M. Ryburn Jr. Cardiac Center, delineated a biochemical-signaling mechanism that converts one muscle-fiber type to another. The findings were reported today in the journal of Genes and Development.

This discovery could make it possible to restore endurance muscle tissue in people who have lost it due to congestive heart failure. People with diabetes might also benefit from a drug that would enhance slow endurance-promoting muscle, which is more sensitive to insulin.

"We believe this pathway provides a molecular explanation for the important effects of aerobic exercise in increasing physical endurance and reducing risk for cardiovascular disease," Williams said. "When people go jogging, molecular events happen in the muscles they are exercising that both enhance their capability to exercise further and improve their health.

"We have shown both in cultured cells and in animals that there is a signaling pathway we can modify to stimulate or reverse what exercise does naturally. We believe it is possible to design a drug which would have this effect."

The study provides evidence that three proteins called calcineurin, NFAT (Nuclear Factor of Activated T cells) and MEF2 (Myocyte Enhancer Factor 2) participate in a pathway that activates a specific subset of genes. These regulatory factors act in concert to control the abundance of proteins found in slow, oxidative skeletal-muscle fibers characteristic of highly fit endurance athletes. When a muscle is tonically active, during jogging for example, the concentration of calcium ions is increased within the muscle cell.

When the calcium level stays high for a sustained period of time it turns on calcineurin, which modifies NFAT so that it moves from the cytoplasm to the cell nucleus. Once NFAT reaches the nucleus, it partners with MEF2 and other proteins to turn on the genes specific for slow, oxidative muscle fibers.

The scientists will investigate further to clarify how this calcium-regulated, calcineurin-dependent pathway affects other muscle types and how it interacts with other cellular activities. This will help them learn if this molecular pathway for converting fast muscle cells to slow muscle cells works the same in humans and if it can be used for a pharmaceutical solution for those unable to exercise.

Other researchers involved in the study were internal medicine postdoctoral fellows, Dr. Eva Chin and Dr. Weiguang Zhu; Dr. Eric Olson, chairman of molecular biology and oncology, director of the Nancy B. and Jake L. Hamon Center for Basic Research in Cancer, and holder of the Nancy B. and Jake L. Hamon Distinguished Chair in Basic Cancer Research; Dr. James Richardson, associate professor of pathology; Dr. Rhonda Bassel-Duby, associate professor of internal medicine; cell and molecular biology graduate student Hai Wu; and internal medicine researcher scientists Caroline Humphries and John Shelton. Williams also holds the James T. Willerson, M.D., Distinguished Chair in Cardiovascular Diseases.

Grants from the Dallas Sweetheart Ball and the National Institutes of Health supported their research.


Story Source:

The above story is based on materials provided by University Of Texas Southwestern Medical Center At Dallas. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas Southwestern Medical Center At Dallas. "Researchers Find Genetic Switch That Explains Effect Of Exercise On Muscles." ScienceDaily. ScienceDaily, 24 August 1998. <www.sciencedaily.com/releases/1998/08/980824072857.htm>.
University Of Texas Southwestern Medical Center At Dallas. (1998, August 24). Researchers Find Genetic Switch That Explains Effect Of Exercise On Muscles. ScienceDaily. Retrieved August 1, 2014 from www.sciencedaily.com/releases/1998/08/980824072857.htm
University Of Texas Southwestern Medical Center At Dallas. "Researchers Find Genetic Switch That Explains Effect Of Exercise On Muscles." ScienceDaily. www.sciencedaily.com/releases/1998/08/980824072857.htm (accessed August 1, 2014).

Share This




More Health & Medicine News

Friday, August 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

House Republicans Vote to Sue Obama Over Healthcare Law

House Republicans Vote to Sue Obama Over Healthcare Law

Reuters - US Online Video (July 31, 2014) The Republican-led House of Representatives votes to sue President Obama, accusing him of overstepping his executive authority in making changes to the Affordable Care Act. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Despite Health Questions, E-Cigs Are Beneficial: Study

Despite Health Questions, E-Cigs Are Beneficial: Study

Newsy (July 31, 2014) Citing 81 previous studies, new research out of London suggests the benefits of smoking e-cigarettes instead of regular ones outweighs the risks. Video provided by Newsy
Powered by NewsLook.com
Dangerous Bacteria Kills One in Florida

Dangerous Bacteria Kills One in Florida

AP (July 31, 2014) Sarasota County, Florida health officials have issued a warning against eating raw oysters and exposing open wounds to coastal and inland waters after a dangerous bacteria killed one person and made another sick. (July 31) Video provided by AP
Powered by NewsLook.com
Health Insurers' Profits Slide

Health Insurers' Profits Slide

Reuters - Business Video Online (July 30, 2014) Obamacare-related costs were said to be behind the profit plunge at Wellpoint and Humana, but Wellpoint sees the new exchanges boosting its earnings for the full year. Fred Katayama 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:
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