Toronto: Spinal-cord damage resulting in paralysis may soon be treated with brain stem cells allowing patients to walk again, according to a new Canadian study recently published in the Journal of Neuroscience.

Although the study has been carried out on rats, human research is predicted to begin in five to ten years.

Neurosurgeon, Dr. Michael Fehlings, of the Krembil Neuroscience Center at Toronto Western Research Institute led a team that injected stem cells extracted from mouse brains to the injury site of paralysed rats with spinal injuries.

The rats were also given a drug cocktail including growth hormone, cyclosporine to prevent rejection and the anti-inflammatory minocycline, which researchers believe attributed to the success of the therapy by reducing the spinal cord inflammation and cell damage and boosting the survival of stem cells.

Researchers found that rats receiving the stem cells restored their walking ability although the injections of stem cells could not completely restore the lost capability.

Fehling said the team had not aimed to regrow the spinal cord but to attempt replacement of one cell type.

The type of cells used in the study was neural precursor cells, which are extracted from mouse brains and ready to turn into a central nervous system cell. Researchers said 30 percent of the stem cells could survive the t ransplant process and help the recipients repair the spinal cord damage.

The researchers said it was necessary for the recipients’ to have viable nerve fibres for the stem cell therapy to work. The stem cells injected in the spinal cord work to develop myelin, the insulating layer around nerve fibers that transmits signals to the brain. About 50 percent of patients have the nerve fibers intact when they get injured. The sooner the therapy is administered also assists in a more effective outcome.

The treatment may as well be applicable to humans, according to the researchers, because the stem cells used for the injection may be extracted from the patients’ own brains using a biopsy needle. Stem cells can be extracted from brains other people donate.

Stem cells are present in many parts of the body such as bone marrow, fetuses, embryos, u mbilical cord b lood and even t eeth. Stem cell research is a hot issue because much of the research would involve fetuses and or embryos, which draws objections from many people. But researchers said the neural precursor cells used are adult stem cells that only help produce nerve cells.