Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Faulty cell membrane repair causes heart disease

05.07.2007
During vigorous exercise, heart muscle cells take a beating. In fact, some of those cells rupture, and if not for a repair process capable of resealing cell membranes, those cells would die and cause heart damage (cardiomyopathy).

Researchers at the University of Iowa Roy J. and Lucille A. Carver College of Medicine have discovered a specific repair mechanism in heart muscle and identified a protein called dysferlin that is critical for resealing heart muscle cell membranes.

The study, led by UI researcher and Howard Hughes Medical Institute investigator Kevin Campbell, Ph.D., also shows that loss of dysferlin causes cardiomyopathy in mice. Furthermore, heart damage in these mice is exaggerated by vigorous exercise or by inherent muscle weakness caused by a muscular dystrophy defect. The results are published in the July 1 issue of the Journal of Clinical Investigation.

Active tissues, like a beating heart or contracting muscle, need mechanisms to repair the inevitable cell membrane tears caused by physical stress and strain. In 2003, Campbell and his colleagues identified dysferlin as a key protein in this vital repair mechanism in skeletal muscle. In humans, dysferlin deficiency -- which leads to faulty muscle membrane repair -- causes three types of muscular dystrophy.

The new study expands knowledge of dysferlin function, showing that dysferlin-mediated membrane repair is also important in heart muscle cells and suggests that inadequate membrane repair can also lead to cardiomyopathy.

"If we could boost this repair mechanism, it might be possible to slow cardiac and skeletal muscle damage in muscular dystrophy patients," said Campbell who also holds the Roy J. Carver Biomedical Research Chair in Molecular Physiology and is head of the department and a UI professor of neurology.

The UI team initially found that young mice that lacked dysferlin showed no heart damage, which is consistent with what is seen in humans with dysferlin mutations. However, a case study describing late-onset cardiomyopathy in a Japanese patient with a dysferlin deficiency prompted the UI team to look at the mice as they aged.

They found that the mice started to develop cardiomyopathy at about one year of age (middle aged for a mouse). The team also found that exercise exaggerated the stress-induced injury in these mice, suggesting that inadequate membrane repair led to cardiomyopathy.

The research team also bred mice that lacked both dysferlin and the protein dystrophin, which is missing in patients with Duchenne muscular dystrophy. These "double knockout" mice had early onset cardiomyopathy, which was much more severe than in mice with either of the single mutations. The results suggest that dysferlin might provide some protection against heart damage in Duchenne patients, at least at a young age, by delaying the onset of cardiomyopathy.

"We hope these findings will stimulate clinicians to look at the cardiac health of muscular dystrophy patients and the overall muscle health of patients with cardiomyopathy," Campbell said.

Jennifer Brown | EurekAlert!
Further information:
http://www.uiowa.edu

Further reports about: Campbell Membrane cardiomyopathy dysferlin dystrophy muscular dystrophy repair

More articles from Life Sciences:

nachricht Topologische Quantenchemie
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

nachricht Topological Quantum Chemistry
21.07.2017 | Max-Planck-Institut für Chemische Physik fester Stoffe

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

Ultrathin device harvests electricity from human motion

24.07.2017 | Power and Electrical Engineering

Scientists announce the quest for high-index materials

24.07.2017 | Materials Sciences

ADIR Project: Lasers Recover Valuable Materials

24.07.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>