Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stroke study reveals a key target for improving treatment

23.06.2008
For over a decade, the drug called tPA has proven its worth as the most effective emergency treatment for stroke. Its promise is blemished by the fact that tPA's brain-saving power fades fast after the third hour of a stroke, and then instead increases the risk of dangerous bleeding in the brain. But a recent study by Swedish and American scientists now show that these problems might be overcome, if a stroke patient first takes a drug currently used to treat leukemia.

The study, which is published online in Nature Medicine by scientists from University of Michigan Medical School and the Ludwig Institute at Karolinska Institutet, is performed on mice.

However, to test the theory in humans the researchers soon will begin a clinical trial in collaboration with the Karolinska University Hospital in Stockholm, using the leukemia drug known as imatinib (Glivec®).Their recent study on mice showed that the drug greatly reduces bleeding, even if tPA wasn't given until five hours after a stroke began.

"Ten years ago our research group identified the growth factor PDGF-CC, and we are now very excited having unraveled a mechanism in the brain involving this factor", comments the Karolinska Institutet team leader, Professor Ulf Eriksson. "This finding has indeed the potential to revolutionize the treatment of stroke."

The new paper details a series of molecular and cellular experiments conducted by the Swedish and American research teams, which began collaborating after hearing of each other's work. They report that tPA apparently causes its risk of bleeding, and leakage of fluid within the brain, by accident. The culprit is tPA's tendency to act upon a protein called PDGF-CC, and the PDGF-alpha receptor that it binds to. This interaction causes the usually impervious blood-brain barrier to become porous, leading to leakage.

Imatinib, however, inhibits the PDGF-alpha receptor permitting tPA to do its main job, which is to down clots that have lodged in the brain's blood vessels. If the clots are not removed, they will cut off blood supply and eventually starving brain tissue until it begins to die.

According to the World Health Organization (WHO), clots in the brain blood vessels causes 80 percent of the 15 million strokes that occur each year worldwide. Five million people die, and 5 million more are permanently disabled, by strokes each year.

"Our findings have immediate clinical relevance, and could be applied to find new treatments that will benefit stroke patients," says senior author, Professor Daniel Lawrence at the U-M Medical School. "By better understanding how the brain regulates the permeability of the blood-brain barrier, and how tPA acts upon that system, we hope to reduce the risks and increase the time window for stroke treatment."

Funding for the study came from the National Institutes of Health, the Ludwig Institute for Cancer Research at Karolinska Institutet, the Novo Nordisk Foundation, the Swedish Research Council, the Swedish Cancer Foundation, the LeDucq Foundation and the Inga-Britt and Arne Lundberg Foundation.

Publication: 'Activation of PDGF-CC by tissue plasminogen activator impairs blood-brain barrier integrity during ischemic stroke', Enming J Su, Linda Fredriksson, Melissa Geyer, Erika Folestad, Jacqueline Cale, Johanna Andrae, Yamei Gao, Kristian Pietras, Kris Mann, Manuel Yepes, Dudley K Strickland, Christer Betsholtz, Ulf Eriksson och Daniel Lawrence Nature Medicine, AOP 22 June 2008, doi 10.1038/nm1787.

For further information, please contact:
Professor Ulf Eriksson
The Ludwig Institute, Karolinska Institutet
Tel: +46(0)8-52487109
Mobil: +46(0)70-6805056
Email: ulf.eriksson@licr.ki.se
Karolinska Institutet is one of the leading medical universities in Europe. Through research, education and information, Karolinska Institutet contributes to improving human health. Each year, the Nobel Assembly at Karolinska Institutet awards the Nobel Prize in Physiology or Medicine.

Katarina Sternudd | idw
Further information:
http://www.vr.se
http://ki.se
http://www.med.umich.edu/news

More articles from Studies and Analyses:

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

nachricht A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg

All articles from Studies and Analyses >>>

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 >>>