UCLA researchers have shown that the brain can be repaired—and brain function can be recovered—after a stroke in animals. The discovery could have important implications for treating a mind-robbing condition known as a white matter stroke, a major cause of dementia.
White matter stroke is a type of ischaemic stroke, in which a blood vessel carrying oxygen to the brain is blocked. Unlike large artery blockages or transient ischaemic attacks, individual white matter strokes, which occur in tiny blood vessels deep within the brain, typically go unnoticed but accumulate over time. They accelerate Alzheimer’s disease due to damage done to areas of the brain involved in memory, planning, walking and problem-solving.
“Despite how common and devastating white matter stroke is there has been little understanding of how the brain responds and if it can recover,” says Thomas Carmichael, senior author of the study and a professor of neurology at the David Geffen School of Medicine at UCLA, USA. “By studying the mechanisms and limitations of brain repair in this type of stroke, we will be able to identify new therapies to prevent disease progression and enhance recovery.”
In a five-year study, Carmichael’s team looked at white matter strokes in animals and found that the brain initiated repair by sending replacement cells to the site, but then the process stalled. The team had a short list of molecular suspects from previous research that they thought might be responsible. Researchers identified a molecular receptor as the likely culprit in stalling the repair; when they blocked the receptor, the animals began to recover from the stroke.
“White matter stroke is an important clinical target for the development of new therapies,” Carmichael says.
The paper was published in the electronic edition of the Proceedings of the National Academy of Sciences.
The study was funded by National Institute of Neurological Disorders and Stroke, the Miriam and Sheldon G Adelson Medical Research Foundation, and the American Stroke Association/Bugher Foundation.