Stem Cells Show Promise for Stroke Recovery
Early study found they can be safely transplanted into the brain; 2 patients showed significant improvement
By Brenda Goodman
MONDAY, April 7, 2014 (HealthDay News) -- In an early test, researchers report they've safely injected stem cells into the brains of 18 patients who had suffered strokes. And two of the patients showed significant improvement.
All the patients saw some improvement in weakness or paralysis within six months of their procedures. Although three people developed complications related to the surgery, they all recovered. There were no adverse reactions to the transplanted stem cells themselves, the study authors said.
What's more, the researchers said, two patients experienced dramatic recoveries almost immediately after the treatments.
Those patients, who were both women, started to regain the ability to talk and walk the morning after their operations. In both cases, they were more than two years past their strokes, a point where doctors wouldn't have expected further recovery.
The results have encouraged researchers to plan larger and longer tests of the procedure, which uses stem cells cultured from donated bone marrow.
An expert who was not involved in the research called it a promising first step.
"It's a small, early human study. It takes multiple steps to get to something clinically useful, and this is a nice, early step," said Dr. Steven Cramer, clinical director of the Stem Cell Research Center at the University of California, Irvine.
The findings were to be presented Monday at the American Association of Neurological Surgeons annual meeting, in San Francisco. The results of studies presented at meetings are considered preliminary until they've been published in peer-reviewed medical journals.
Strokes occur when a blood clot or bleeding disrupts blood flow to the brain. Brain cells deprived of oxygen and nutrients quickly die. Strokes kill about 137,000 Americans each year, according to the American Stroke Association, making them a leading cause of death in the United States, but they disable many more.
Some 7 million American adults are estimated to be living with the aftereffects of stroke, which can include difficulty speaking, weakness, paralysis, and trouble with thinking and memory. Intensive physical therapy can help people regain abilities they've lost after a stroke, but there's currently no way to repair damaged brain tissue, experts say.
In animal studies, stem cells have shown great potential to help heal the brain damage caused by strokes.
The new research is one of the first tests of the treatment in humans, the researchers said.
Participants in the new study ranged in age from 33 to 75. Each had experienced a stroke caused by a blood clot at least six months before their procedures. And each had been left with some weakness or paralysis in a limb.
The stem cells used in the study came from bone marrow donated by two people who were unrelated to the study participants. Special cells called mesenchymal stem cells were isolated from the marrow and grown in a lab, where they were treated with a gene that's thought to enhance their healing abilities.