Grant: Operating Grant

For nearly 300,000 Canadians who currently are living with the after effects of stroke, there are no treatments that can reverse the massive and progressive loss of cells called neurons in the brain that cause severe motor and cognitive deficits. Historically, scientists believed that the adult human brain could not make new neurons suggesting that if we wanted to make new neurons we would have to transplant them into the brain. But within the last 10 years there has been new hope for future treatments that will replace the lost neurons with new cells that are developed within the adult brain. This hope arose since scientists discovered that the adult brain makes new neurons through the process of neurogenesis in many species, including humans. Remarkably, following a stroke new dividing cells in the brain go to the site of the injury produced by the stroke, suggesting that the brain might be trying to repair itself. This suggests that enhancing neurogenesis could aid in recovery. However, it is still unknown what role the dividing cells and new neurons have during stroke recovery. The objective of this work is to determine the function of the new cells in the adult brain and determine if they enhance recovery. By using a variety of mouse models we have created, we can specifically remove the new cells, or alternatively, increase the number of new cells in the adult brain, and determine how this affects mouse behavior after a stroke. We will also determine if the new neurons that develop at the site of injury after stroke can generate electrical signals with the surrounding resident cells, and thus determine whether these new neurons are functioning correctly. The results from these experiments will provide us with important insights into the role of the new neurons in the adult brain during stroke recovery, a finding which will be essential for harnessing the potential of these new neurons in treatments designed to aid in stroke recovery.