Dr. Noël Ghanem
University of Ottawa
The interruption of blood flow or the rupture of blood vessels in the brain which lead to stroke causes brain cells (neurons) in the affected area to die. Ideally the brain could be enabled to grow new neurons post-stroke to replace those which have been damaged or destroyed. This kind of replacement might be achieved with the use of stem cells, which can develop into any of the body’s many different tissues, including brain cells.
Dr. Noël Ghanem, a post-doctoral fellow with the University of Ottawa’s Neuroscience Research Group, has been looking at new ways of bringing this prospect closer to reality. According to Dr. Ghanem, previous attempts to introduce stem cells into the brain have been largely ineffective, since less than 0.1 per cent of such cells actually grow into new neurons.
He maintains that the brain’s own recently discovered population of stem cells, though small in number and generally inactive, is a more promising source of replacement neurons.
Dr. Ghanem is studying the function of two retinoblastoma genes, which play a critical role in controlling the number and expansion of stem cells and the generation of new neurons. He believes the action of these genes could be manipulated so that more neurons derived from stem cells become available for recovery after brain injury.
While the effect of manipulating these genes is being demonstrated in mice, Dr. Ghanem and his colleagues are conducting, in parallel, experiments to look for other genes that play a part in helping new neurons migrate to the site of injuries caused by the stroke.
The result should be a precisely targeted therapy, restoring capacity in the brain exactly where it has been lost. Dr. Ghanem’s work is supervised by Dr. Ruth Slack.
Supported by AstraZeneca Canada Inc.