In a surprising discovery, scientists from the University of California, Irvine, have found a new cause of brain bleeding that could change how we understand and treat age-related brain problems.
Their study, published in the Journal of Neuroinflammation, shows that tiny brain bleeds—called cerebral microbleeds—can be caused by damaged red blood cells, not just by broken blood vessels. This finding opens a new path for research and treatment of brain conditions in older people.
Cerebral microbleeds are very small spots of bleeding in the brain. They are often found in older adults or in people with health problems like high blood pressure, Alzheimer’s disease, or after a stroke. Until now, most experts believed that weak or broken blood vessels were the main reason for these microbleeds. But this study suggests something else might be going on.
The research team, led by Dr. Mark Fisher and Dr. Xiangmin Xu, wanted to learn more about what happens to red blood cells when they get old or damaged. To study this, they used a chemical called tert-butyl hydroperoxide to make the red blood cells go through something called oxidative stress.
This is a process that mimics aging or damage. Then, they labeled these damaged cells with a glowing marker and injected them into mice to watch what would happen.
The scientists carefully watched the mice’s brains and saw that the damaged red blood cells got stuck in the brain’s tiniest blood vessels, known as capillaries. These blockages didn’t go unnoticed. The brain’s immune cells, called microglia, moved in to clean up the mess. But instead of solving the problem, this cleanup process led to tiny bleeds in the brain.
This finding changes what we know about how microbleeds happen. It’s not just the blood vessels we need to worry about. The red blood cells themselves might play a key role.
“Our findings may have profound clinical implications,” said Dr. Fisher. “We’ve shown that damage to red blood cells can directly cause microbleeds, even when the blood vessels themselves appear normal.”
This discovery could be very important for people with health conditions that lead to oxidative stress—such as high blood pressure or diabetes. It also gives scientists a new way to think about Alzheimer’s disease, since microbleeds often appear in people with that illness.
The next step for the researchers is to find out how the brain’s small blood vessels handle these damaged cells and how this might connect to strokes or other brain injuries. They also hope to discover if it’s possible to stop red blood cells from causing damage in the first place.
If future treatments can improve red blood cell health or help the brain’s immune system respond better, it could lead to new ways to protect brain health—especially as people get older.
While this study was done in mice and is still in early stages, it shows how important it is to keep both your blood and brain healthy. Managing health problems like high blood pressure and diabetes, eating a healthy diet, staying active, and avoiding smoking can all help protect your brain as you age.
This exciting research shows how something as small as a red blood cell can play a big role in brain health. It gives hope that one day we might prevent or better treat serious conditions like stroke and dementia by paying closer attention to our blood health.
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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