Featured Research

from universities, journals, and other organizations

Sprinters' Secret Weapon

Date:
January 16, 2001
Source:
University Of Michigan
Summary:
The same protein that helped Maurice Greene become the "world's fastest man" at this summer's Olympic Games in Australia could one day help millions of Americans who suffer from a common type of progressive heart failure, according to a new animal study by scientists at the University of Michigan Medical School.

ANN ARBOR --- The same protein that helped Maurice Greene become the "world's fastest man" at this summer's Olympic Games in Australia could one day help millions of Americans who suffer from a common type of progressive heart failure, according to a new animal study by scientists at the University of Michigan Medical School.

This protein, called parvalbumin, helps skeletal muscle fibers in the arms and legs contract and relax rapidly and efficiently. Olympic sprinters have high levels of parvalbumin in their skeletal muscle, which helps explain why they can run faster than the rest of us, according to Joseph M. Metzger, Ph.D., associate professor of physiology and of internal medicine in the U-M Medical School. Parvalbumin works like a sponge helping skeletal muscle cells relax faster by soaking up calcium ions.

In a study published in the Jan. 15 issue of the Journal of Clinical Investigation, Metzger and a team of U-M researchers show for the first time that parvalbumin also can improve heart function in laboratory rats---restoring normal relaxation rates in hearts with a condition that mimics the abnormally slow cardiac relaxation common in human heart failure.

"Although important and challenging scientific obstacles remain, our findings raise the intriguing possibility of one day using parvalbumin therapy to treat progressive heart failure in humans," Metzger says.

Exacerbated by high-fat diets and not enough exercise, heart failure is a growing medical problem affecting approximately five million Americans, with more than 700,000 new cases reported each year. About 40 percent of the time, heart failure is associated with a condition called diastolic dysfunction where the heart contracts normally, but doesn't relax fast enough to allow the cardiac chambers to fill with blood before the next contraction. "In a healthy, living heart all cells work together like an orchestra with one conductor," Metzger says. "In a heart with diastolic dysfunction, the cells relax too slowly, so the heart pumps inefficiently and body tissues are starved for oxygen."

The gene for parvalbumin is found in every cell in the body, but it is not naturally activated or expressed in heart muscle cells. To test the protein's ability to relax cardiac muscle, U-M researchers used a common adenovirus to deliver human parvalbumin genetic material into heart cells of laboratory rats used in the study.

In three separate experiments, all reported in the Journal of Clinical Investigation article, U-M researchers found that:

* When human parvalbumin was injected into the left ventricle of the heart, cardiac relaxation speed was significantly faster than in control animals that did not receive the gene.

* Pressure measurements inside the left ventricle confirmed that rats receiving parvalbumin injections had a much faster relaxation time than control rats.

* Echocardiograms showed that the time interval from aortic valve closure to mitral valve opening in rats receiving parvalbumin was shorter than in control rats.

* Parvalbumin restored normal cardiac relaxation rates in an experimental animal model with the same type of slow relaxation found in human heart failure.

"This was a proof-of-principle, short-term study," Metzger says. "Since adenoviral vectors elicit an immune response after about six days in animals, they aren't suitable for this application in humans where parvalbumin must be expressed for long periods of time. There are many new adenoviral-related vectors in development, however, which could be just as effective without provoking an immune response."

The U-M study was funded with grants from the American Heart Association, the National Institutes of Health, the Culpepper Foundation and the U-M Center for Integrative Genomics. The U-M has applied for a patent on the technology.

Michael Szatkowski, M.D., a senior research fellow in the U-M Medical School and a neonatology fellow at Thomas Jefferson University in Philadelphia, is first author on the paper. Other U-M collaborators include Margaret V. Westfall, assistant professor of physiology and surgery; Carly A. Gomez, M.D., clinical assistant professor of pediatrics and communicable diseases; Philip A. Wahr, Ph.D., assistant research scientist; graduate students Daniel E. Michele and Christiana DelloRusso; and research associates Immanuel I. Turner, Katie E. Hong and Faris P. Albayya.


Story Source:

The above story is based on materials provided by University Of Michigan. Note: Materials may be edited for content and length.


Cite This Page:

University Of Michigan. "Sprinters' Secret Weapon." ScienceDaily. ScienceDaily, 16 January 2001. <www.sciencedaily.com/releases/2001/01/010111074516.htm>.
University Of Michigan. (2001, January 16). Sprinters' Secret Weapon. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2001/01/010111074516.htm
University Of Michigan. "Sprinters' Secret Weapon." ScienceDaily. www.sciencedaily.com/releases/2001/01/010111074516.htm (accessed September 22, 2014).

Share This



More Health & Medicine News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Ebola Doctor Says Border Controls Critical

Ebola Doctor Says Border Controls Critical

AP (Sep. 22, 2014) A Florida doctor who helped fight the expanding Ebola outbreak in West Africa says the disease can be stopped, but only if nations quickly step up their response and make border control a priority. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) Video provided by AP
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