Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers induce heart cells to proliferate

03.05.2005


Could lead to strategies to regenerate tissue after heart attack



In the best documented effort to date, researchers from the Howard Hughes Medical Institute at Children’s Hospital Boston and Harvard Medical School have successfully induced adult heart-muscle cells to divide and multiply.

Heart-muscle cells, or cardiomyocytes, were previously considered incapable of replicating in mammals after birth, which is why heart attack is such a problem: once killed, heart tissue can’t regenerate. Dr. Mark Keating and Dr. Felix Engel now show that an enzyme known as p38 MAP kinase suppresses cardiomyocyte replication, and that inhibiting p38 enables these cells to proliferate. Their report appears in the May 15 issue of Genes & Development (published online May 3).


Keating, Engel and colleagues first showed in fetal rats that increased p38 activity correlates with reduced cardiac growth, and that reduced p38 activity correlates with accelerated cardiac growth. Then, working with adult cardiomyocytes, they demonstrated p38’s role in every major step of cell replication.

First, in cultures of cardiomyocytes from rats, they showed that activation of p38 reduced DNA synthesis, the first key step in cell replication, and that inhibition of p38 increased DNA synthesis. Second, they showed that p38 regulates the activity of genes required for mitosis (division of the cell nucleus in two), a second key step in replication. When mice were bred to lack p38, mitosis in their cardiomyocytes increased by more than 90 percent. Finally, p38 inhibition promoted cytokinesis, the last step of replication in which the entire cell divides to form two separate cells. Growth factors were needed to get the full effect.

"This is just one baby step toward regenerative therapy, but it’s an important one," says Keating. "Inhibiting p38 is now a candidate therapeutic strategy."

When a human heart is injured, it cannot ’’grow back’’ the damaged muscle, which is instead replaced by scar tissue. Too much scarring can impair the heart’s ability to pump and can lead to life-threatening arrhythmias. "If you want to prevent hearts from becoming scarred, a regenerative therapy is needed," Keating says.

Keating, Engel and colleagues are now studying rodents with simulated heart attacks to see whether agents that inhibit p38 would improve heart function and induce heart regeneration with reduced scar formation. Keating believes this approach, if successful, would prove more practical than stem-cell therapy, which would involve implanting whole cardiomyocytes.

"From a practical perspective, we think that delivering proteins or small molecules is much more likely to succeed," he says. "It would be like taking the drug epoetin alfa to stimulate red blood cell production, as opposed to getting a blood transfusion. Instead of borrowing cells, you’re making them yourself."

p38 was chosen for study because it is known to be important in the differentiation of cardiomyocytes. Once cells differentiate into their mature form, they usually lose their ability to proliferate. This study shows that ability can be revived.

Bess Andrews | EurekAlert!
Further information:
http://www.childrens.harvard.edu

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>