Paralysed rats who received transplants of adult mouse brain stem cells were able to partially restore limb movement, researchers said in Wednesday’s issue of The Journal of Neuroscience.
Called neuronal precursors, the stem cells from the brains of adult mice are able to transform themselves into cells of the central nervous system and other tissues.
The researchers said they were hopeful the technique could in coming years lead to new treatments for people with spinal cord injuries.
A team of Canadian researchers from the Krembil Neuroscience Centre in Toronto injected stem cells from adult mice brains into rats whose spines had been crushed. The stem cells migrated to the damaged area and changed into myelin-producing cells.
Made of lipids and proteins, myelin forms an insulating layer around nerve fibers that transmits signals from the brain.
While the injured rats did not walk again, ”they recovered significant walking ability. They had better coordination of their joints and a better ability to support their weight,” said Michael Fehlings, one of the leading researchers of the study.
”This work breaks new ground by showing that therapeutically useful stem cells can be derived from the adult brain of rodents, and that these cells can be caused to differentiate into the types of cells that are useful for repairing the damaged spinal cord,” said Osvald Steward, director of the Reeve-Irvine Research Centre for Spinal Cord Injury at the University of California.
Fehlings said he hoped similar techniques could be tested in humans in five or ten years, after more animal research is carried out.
He said neuronal precursors could be extracted with a needle from the area of the human brain where stem cells reside. These cells, in turn, could be injected near the damaged area of the spinal cord.
Fehlings said half spinal cord injury sufferers could benefit from the treatment as long as enough nerve cells remained intact even without their myelin covering.
The researchers also found in their experiments with mice and rats that transplanting stem cells to the injured spine is most efficient if done up to two weeks after the initial injury.
One focus of future research, they said, will be to determine the reason why stem cells transplanted weeks or months later fail to function or sometimes even survive.
About 11 000 people in the United States sustain spinal cord injuries each year, most often in traffic accidents, costing the health care system almost $10-billion. – AFP
