Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cool brain opens stroke treatment window, say Stanford researchers

06.02.2004


Treating stroke is all a matter of timing: therapy delivered too late misses the critical window when neurons can still be saved. A report by Stanford University School of Medicine researchers shows that cooling the brain can lengthen the therapeutic window, giving doctors more time to protect brain cells.



The idea of cooling the brain isn’t new. Study leader Gary Steinberg, MD, PhD, the Lacroute-Hearst Professor of Neurosurgery and the Neurosciences, said he started cooling brains during brain surgery in 1991. For some types of surgeries, a brain that’s 4 degrees cooler than normal seems to resist injury better than a brain at normal body temperature.

In collaboration with Robert Sapolsky, PhD, the John A. and Cynthia Fry Gunn Professor of Biological Sciences, Steinberg has combined this cooling treatment with a form of gene therapy. Together the approaches work better than either technique on its own to save neurons after a stroke. What’s more, cooling the brains in rats slowed the neurons’ demise, giving researchers more time to administer additional treatment.


"We think this work has considerable potential," Steinberg said. The study is published in the February issue of the journal Stroke.

In past experiments, Steinberg’s and Sapolsky’s groups have shown that giving rats a form of gene therapy within 90 minutes after a stroke can help brain cells survive. The gene they insert, called Bcl-2, prevents cells from following a ritualized form of cell death. Proteins involved in this fatal pathway usually skyrocket after a stroke and brain cells die en masse.

Although the gene therapy’s success was good news, giving Bcl-2 after the initial 90-minute window had no effect - the cell-death proteins had already been released and the cells were beyond recovery. However, Steinberg said it is rare for stroke patients to receive treatment within that narrow 90-minute time frame.

Steinberg and his colleagues thought that chilling the brains might slow the release of cell-death molecules, allowing a longer window in which Bcl-2 treatment could be effective.

In the study, researchers cut off the blood supply to a portion of the brain in rats, simulating a stroke. Some rats recovered at the normal body temperature while others had their temperature lowered by 4 degrees until the researchers gave Bcl-2 gene therapy five hours later.

The number of surviving neurons was the same in all mice that had no gene therapy and in mice that had gene therapy without cooling. However, the mice in which the lowered body temperature was followed by gene therapy had two to three times more neurons surviving two days after the stroke.

Steinberg said if this finding holds true in humans then chilling the brain may give doctors more time to treat stroke patients. This longer opening could make the difference in enabling patients to retain such functions as control of their limbs or the ability to speak normally after a stroke.

Steinberg added that for now, Bcl-2 gene therapy isn’t an option for humans because the method used to insert the gene hasn’t been perfected. Rather, he said researchers can begin looking at other treatments that may be possible to complete within the longer therapeutic window. These treatments include one of a wide range of proteins that, like Bcl-2, thwart the cell-suicide pathway and keep cells alive.

"We’re also pursuing hypothermia with other genes to extend the therapeutic window," Steinberg said.

Heng Zhao, PhD, research associate, was lead author of the study. Midori Yenari, MD, associate professor of neurosurgery and of neurology and neurological sciences, also contributed to the work.


Stanford University Medical Center integrates research, medical education and patient care at its three institutions - Stanford University School of Medicine, Stanford Hospital & Clinics and Lucile Packard Children’s Hospital at Stanford. For more information, please visit the Web site of the medical center’s Office of Communication & Public Affairs at http://mednews.stanford.edu.

PRINT MEDIA CONTACT: Amy Adams at (650) 723-3900 (amyadams@stanford.edu)
BROADCAST MEDIA CONTACT: M.A. Malone at (650) 723-6912 (mamalone@stanford.edu)

Amy Adams | EurekAlert!
Further information:
http://mednews.stanford.edu

More articles from Health and Medicine:

nachricht Biofilm discovery suggests new way to prevent dangerous infections
23.05.2017 | University of Texas at Austin

nachricht Another reason to exercise: Burning bone fat -- a key to better bone health
19.05.2017 | University of North Carolina Health Care

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>