Cell-saving drugs could reduce brain damage after stroke

March 26, 2014
Micrograph showing cortical pseudolaminar necrosis, a finding seen in strokes on medical imaging and at autopsy. H&E-LFB stain. Credit: Nephron/Wikipedia

Long-term brain damage caused by stroke could be reduced by saving cells called pericytes that control blood flow in capillaries, reports a new study led by scientists from University College London.

Until now, many scientists believed that blood flow within the brain was solely controlled by changes in the diameter of arterioles, that branch out from arteries into smaller capillaries. The latest research reveals that the brain's blood supply is in fact chiefly controlled by the narrowing or widening of capillaries as pericytes tighten or loosen around them.

The study, published this week in Nature, shows not only that pericytes are the main regulator of blood flow to the brain, but also that they tighten and die around after stroke. This significantly impairs blood flow in the long term, causing lasting damage to brain cells. The team of scientists from UCL, Oxford University and the University of Copenhagen showed that certain chemicals could halve pericyte death from simulated stroke in the lab, and hope to develop these into drugs to treat .

"At present, clinicians can remove clots blocking blood flow to the brain if reach hospital early enough," explains Professor David Attwell of UCL's Department of Neuroscience, Physiology & Pharmacology, who led the study. "However, the capillary constriction produced by pericytes may, by restricting the blood supply for a long time, cause further damage to nerve cells even after the clot is removed. Our latest research suggests that devising drugs to prevent capillary constriction may offer new therapies for reducing the disability caused by stroke."

"This discovery offers radically new treatment approaches for stroke," says study co-author Professor Alastair Buchan, Dean of Medicine and Head of the Medical Sciences Division at Oxford University. "Importantly, we should now be able to identify drugs that target these cells. If we are able to prevent pericytes from dying, it should help restore blood flow in the brain to normal and prevent the ongoing slow damage we see after a which causes so much neurological disability in our patients."

The new research also gives insight into the mechanisms underlying the use of functional magnetic resonance imaging to detect blood flow changes in the brain.

"Functional imaging allows us to see the activity of nerve cells within the human but until now we didn't quite know what we were looking at," explains Professor Attwell. "We have shown that pericytes initiate the increase in seen when become active, so we now know that functional imaging signals are caused by a pericyte-mediated increase of capillary diameter. Knowing exactly what functional imaging shows will help us to better understand and interpret what we see."

Explore further: Important step towards stem cell-based treatment for stroke

More information: Capillary pericytes regulate cerebral blood flow in health and disease, DOI: 10.1038/nature13165

Related Stories

Important step towards stem cell-based treatment for stroke

October 25, 2013

Brain infarction or stroke is caused by a blood clot blocking a blood vessel in the brain, which leads to interruption of blood flow and shortage of oxygen. Now a reserach group at Lund University, Sweden, has taken an important ...

Study breaks blood-brain barriers to understanding Alzheimer's

December 13, 2013

A study in mice shows how a breakdown of the brain's blood vessels may amplify or cause problems associated with Alzheimer's disease. The results published in Nature Communications suggest that blood vessel cells called pericytes ...

Recommended for you

Motivation to bully is regulated by brain reward circuits

June 29, 2016

Individual differences in the motivation to engage in or to avoid aggressive social interaction (bullying) are mediated by the basal forebrain, lateral habenula circuit in the brain, according to a study conducted at the ...

New clues about the aging brain's memory functions

June 29, 2016

A European study led by Umeå University Professor Lars Nyberg, has shown that the dopamine D2 receptor is linked to the long-term episodic memory, which function often reduces with age and due to dementia. This new insight ...

New technology could deliver drugs to brain injuries

June 28, 2016

A new study led by scientists at the Sanford Burnham Prebys Medical Discovery Institute (SBP) describes a technology that could lead to new therapeutics for traumatic brain injuries. The discovery, published today in Nature ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.