Study raises stroke treatment hopes

Brain nerve cells have a natural ability to protect themselves from damage during the onset of a stroke, possibly paving the way for new treatments to help victims, scientists have found. A team from the University of Bristol, south west England, found that some nerve cells in the brain have developed a way of protecting themselves from the drop in blood supply and nutrients they suffer during a stoke, where blood vessels in the head rupture. It has raised hope of new ways of treating what is the third largest killer in the United Kingdom and which can lead to the loss of speech and movement in people who survive. Dr Jack Mellor, from the university's school of physiology and pharmacology, who led the research, said "We hope that if we can understand why some nerve cells are resistant to stroke damage we may be able to develop strategies to protect those cells that are sensitive. "Historically, stroke has been very difficult to treat because of its unpredictability and the need to administer drugs within minutes of the onset of a stroke. These problems will not be overcome by our research but our findings do reveal a natural protection mechanism in some nerve cells, which may be useful in developing treatments to protect other nerve cell types." Writing in the "Journal of Neuroscience", Wednesday the researchers looked at two types of nerve cell in the hippocampus, the area of the brain linked to memory and navigation. One of these cell types, the CA1 cell is highly susceptible to damage after stroke whereas the other, the CA3 cell, is much more resistant despite many other similarities between the two cell types. The researchers found through a simulated test in a lab that the CA3 cells possess a mechanism for reducing their susceptibility during, and immediately after, a stroke. They believe it was caused by protecting themselves against the neurotransmitter glutamate, which is released in large quantities during strokes. Dr Sharlin Ahmed, from The Stroke Association, said "Getting someone to hospital as quickly as possible if they are displaying stroke symptoms is absolutely crucial to the level of recovery they can make. "This is a very important piece of research as it was previously thought that brain cells damaged by stroke died or were dependent on surrounding cells adopting the functions of the damaged ones. "However this study shows that cells do in fact have natural defence mechanisms, therefore, this offers hope that through further research we could potentially learn how to protect more susceptible nerve cells and reduce the level of disability that many stroke survivors are left with."