When someone has a stroke, quick treatment is key. Doctors can sometimes remove or dissolve the blood clot that caused the stroke, but this only works in a short window of time.
After that, many people are left with serious problems that can last for years, such as trouble walking, speaking, or remembering things.
The main form of treatment after that point is physical therapy and symptom management. But scientists are now looking at new ways to help the brain heal after a stroke.
Exercise has long been known to help people recover from strokes and may even help prevent them. However, most stroke patients are older and too weak to do the kind of exercise that gives real benefits.
So, researchers in Japan wanted to understand how exercise helps the brain at a biological level—and whether they could use that knowledge to create a new kind of treatment.
In a study published in the journal MedComm, a team from Juntendo University School of Medicine, led by Dr. Toshiki Inaba, Dr. Nobukazu Miyamoto, and Dr. Nobutaka Hattori, explored how mitochondria—the tiny power plants inside our cells—play a key role in brain repair after a stroke.
The idea came from an earlier discovery that mitochondria can move from one cell to another. Dr. Miyamoto first saw this during a research fellowship at Massachusetts General Hospital and Harvard Medical School. This led the team to wonder: could these traveling mitochondria be used to help stroke patients?
To find out, the researchers used mice that had symptoms of stroke or dementia. Some of these mice were put on a low-intensity treadmill exercise routine. The scientists then looked at the brains and behavior of both the exercising and non-exercising mice.
The results were exciting. The mice that exercised had less damage to the brain’s white matter—the parts of the brain that help send messages between brain cells. They also moved better, remembered more, and showed fewer signs of post-stroke problems.
But the most interesting finding was what happened inside the mice’s bodies. Exercise increased the number of mitochondria in muscle and blood.
These extra mitochondria were carried through the blood by platelets, which usually help with blood clotting. In this case, the platelets acted like delivery trucks, taking the mitochondria from the muscles to the brain.
Once in the brain, the mitochondria reached different types of brain cells—including neurons and support cells that protect and nourish the brain. These mitochondria helped the cells survive in low-oxygen areas, repaired white matter, and reduced the damage caused by the stroke.
Dr. Inaba explained that there are still challenges before this treatment can be used in people, but the results offer hope. Right now, there are few options for treating stroke damage and no proven treatments to stop the development of vascular dementia. This new approach could change that.
If future studies and human trials go well, we might one day treat stroke patients with transfusions of mitochondria-packed platelets—giving them some of the brain-healing benefits of exercise without the need for strenuous workouts.
This research opens new doors not just for stroke recovery, but also for treating other brain diseases that involve damaged cells and poor energy supply. It’s a step toward a future where brain injuries might be healed using the body’s own power sources—its mitochondria.
If you care about stroke, please read studies that diets high in flavonoids could help reduce stroke risk, and MIND diet could slow down cognitive decline after stroke.
For more health information, please see recent studies about antioxidants that could help reduce the risk of dementia, and tea and coffee may help lower your risk of stroke, dementia.
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