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 Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

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: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Stiffness matters

22.02.2018 | Life Sciences

Magnetic field traces gas and dust swirling around supermassive black hole

22.02.2018 | Physics and Astronomy

First evidence of surprising ocean warming around Galápagos corals

22.02.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>