Cells could speed stroke recovery, study finds
By TINA HESMAN Post-Dispatch (4/3/03)
Stem cells extracted from umbilical cords may one day cure damage done by strokes, suggests new research by St. Louis University neurologists.
The researchers blocked an artery in the brain of rats to mimic strokes caused by blood clots, said Dr. Yi Pan, the neurologist who led the study. After the stroke, the researchers injected stem cells into arteries in the rats' necks.
The stem cells were originally taken from umbilical cord blood. Previous studies have shown that such cells may have the potential to produce many other cell types but may not be as versatile as embryonic stem cells.
The scientists first cultured the stem cells in laboratory dishes, feeding the cells certain nutrients and growth factors. The treatment produces cells that look like brain cells, Pan said.
After a week, the rats that got stem cell injections could pull tape off their paws about as well as they could before the stroke. Rats that got only a saline solution took nearly three weeks to return to normal. The rats treated with stem cells also recovered other movements slightly more quickly than untreated rats, Pan said.
The results are encouraging, Pan said, but may not indicate that stem cells taken from cord blood can replace injured brain cells.
When the researchers examined brains from the rats, they found that most of the stem cells had died, even though the rats had recovered. That could indicate that stem cells produce proteins or hormones that may help heal damaged brain cells or direct neighboring neurons to take over the jobs of dead and dying cells, Pan said.
Pan presented the results of the study Tuesday at the annual meeting of the American Academy of Neurology in Honolulu.