Researchers in the US have discovered a previously unknown role for the brain’s immune cells that are triggered during ischaemic stroke.
The team at University of Virginia School of Medicine (UVA) found that microglia cells also help to regulate blood flow and maintain the brain’s critical blood vessels.
The findings may prove important in stroke, as well as cognitive decline and dementia, the researchers said.
“Precise blood vessel function is critical to accommodate the extreme energy demands of the brain for normal brain function,” said UVA’s Ukpong B. Eyo, PhD, of UVA’s Department of Neuroscience, the UVA Brain Institute and UVA’s Center for Brain Immunology and Glia (BIG).
“These findings suggest previously unknown roles for these brain cells in the proper maintenance of blood delivery to the brain and provide novel opportunities to intervene in contexts where blood perfusion to the brain is impaired.”
Scientists have long known that microglia play an important role in responding to injury and infection in the brain.
Ischaemic stroke can induce rapid activation of these cells, causing inflammation in the brain. However, microglial activation may also be critical for neurogenesis and recovery after cerebral ischemia.
Until now scientists were unsure what role microglia play in maintaining blood cells in a normal, healthy brain.
This new research reveals that microglia play a critical supportive role by tending to blood vessels and regulating blood flow.
This includes helping to regulate the diameter of capillaries and maybe even restricting or increasing blood flow as required.
The researchers believe that the findings could have significant implications for diseases that affect the small vessels in the brain.
“We are currently expanding this research into an Alzheimer’s disease context in rodents to investigate whether the novel phenomenon is altered in mouse models of the disease and determine whether we could target the mechanisms we uncovered to improve known deficits in blood flow in such a mouse model of Alzheimer’s,” Eyo said.
“Our hope is that these findings in the lab could translate into new therapies in the clinic that would improve outcomes for patients.”
Image by Dan Addison | UVA Communications
