SATURDAY, April 8, 2006 (HealthDay News) -- Researchers say they've lessened the effects of stroke in rats by transplanting stem cells into the rodents' brains.
The treatment also seemed to help rats fight a condition similar to human cerebral palsy.
There's no indication yet that the treatment will work in humans, and the lead researcher cautioned that the strategy is no "magic bullet." However, tests in people could begin as early as next year, said Cesario V. Borlongan, an associate professor of neurology at the Medical College of Georgia in Augusta.
The treatment is "not something that will totally cure stroke or cerebral palsy," Borlongan said. Still, he said, it could help.
Despite decades of research, stroke remains extremely common and very difficult to treat. According to Borlongan, 3,000 Americans suffer strokes each day, but only about 100 are helped by newer remedies such as tPA, a powerful clot-busting drug.
Cerebral palsy, a disabling neurological disorder of childhood, currently has no effective treatment, Borlongan noted.
However, because they have the ability to transform themselves into various types of body cells, stem cells have been thought to offer hope as a means of regenerating diseased or injured tissues. In fact, neuroscientists have been experimenting with stem cell transplants in animals for several years, but with mixed results.
In the new study, funded by Athersys Inc., a U.S. biopharmaceutical company, Borlongan and colleagues transplanted human bone marrow cells into the brains of rats who had suffered strokes. By avoiding stem cells sourced from embryos or fetuses, "we feel we've circumvented the ethical as well as political issues," Borlongan noted.
He and his colleagues reported their findings Friday at the American Academy of Neurology annual meeting, in San Diego.
Movement skills in the stroke-afflicted rats improved by 25 percent after stem cell treatment, Borlongan said. The improvement came even though the treatment was given seven days after a stroke.
A 25 percent improvement could translate into significant changes in how human patients get around, Borlongan said. Bedridden patients may be able to use a wheelchair, and wheelchair-bound patients might move up to a walker, he said.
Researchers also saw about a 25 percent improvement in treated rats affected with a condition equivalent to human cerebral palsy. However, the researchers only watched them for 14 days. Unlike the rats in the stroke study, these rodents were injected with rat -- not human -- stem cells.
So, what's at work here? In the mice that had strokes, Borlongan said the stem cell transplants appear to reawaken stunned brain cells around the area of injury.
"The transplants appear to be rescuing the dying cells," he said.
Over the next year, Borlongan said, researchers hope to test their treatment in larger animals, such as primates and pigs. Human tests may begin by 2007.
The Georgia researcher said it's not clear how much the treatment will cost, and it may also prove difficult to administer unless researchers figure out a way to avoid injecting cells directly into the brain.
Also, researchers need to figure out if the treatment affects other brain skills, such as learning and memory, he said.
More information
Learn more about stem cells from the National Institutes of Health.
