Scientists from the University of California, Irvine, have made an exciting discovery about what might cause brain bleeds, especially in older adults.
Their study shows that old or damaged red blood cells can play a key role in brain hemorrhages, even without the blood vessels being injured.
This research was published in the Journal of Neuroinflammation and was led by Dr. Mark Fisher and Dr. Xiangmin Xu. The scientists wanted to understand how brain bleeds, also known as cerebral microbleeds, can occur.
These tiny bleeds are linked to many brain problems that happen with aging, such as high blood pressure, Alzheimer’s disease, and strokes.
To explore this, the researchers did an experiment using mice. They first damaged red blood cells using a chemical called tert-butyl hydroperoxide to create oxidative stress. Then, they labeled these red blood cells with a glowing marker so they could be tracked. After injecting the cells into the mice, the scientists watched what happened inside the brain.
What they saw was surprising. The old red blood cells got stuck in the tiny blood vessels of the brain, called capillaries. Then, a type of immune cell in the brain, called microglia, came along and swallowed these red blood cells. This process led to bleeding in the brain tissue.
This finding challenges what scientists used to think—that brain bleeds only happen when blood vessels break or are damaged. Now, we know that the way old blood cells interact with the brain’s blood vessels can also lead to bleeding.
This discovery is important because it could help doctors understand and treat brain conditions in a new way. If we can stop or slow down this process, we might be able to prevent some strokes or other brain problems linked to aging.
The researchers say their next steps will be to study how the brain clears out these red blood cells and how that process is linked to other types of strokes.
This study is a big step forward in learning how to protect brain health as people get older. It could lead to new treatments that help prevent brain bleeds before they start.
If you care about stroke, please read studies about Half of people with heart rhythm diseases dying of heart attack, stroke and findings of New method reduces heart attacks and strokes over five years.
For more about stroke, please read studies about Blood thinner drug prevents strokes in hidden heart issues and findings of Intensive blood pressure treatments could prevent stroke in older adults.
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