Brain-swelling mechanism pinpointed
UBC researchers have uncovered the cause of brain swelling after trauma to the head. Treatment options for brain swelling are currently limited, and although the technique used by the researchers to block swelling and cell death is unlikely to work quickly enough to mitigate swelling in the case of real head trauma, the discovery provides a target for drug development.
By turning off a single gene, scientists from the Djavad Mowafaghian Centre for Brain Health (DMCBH) were able to successfully stop swelling in rodent brains. Brain swelling is a gradual process that becomes life threatening within days of the injury, and is caused by sodium chloride drawing water into the nerve cells. This swelling (cytotoxic edema) eventually kills brain cells.
The team, including brain researcher Brian MacVicar, co-director of DMCBH with the Vancouver Coastal Health Research Institute and the study’s principal investigator; Terrance Snutch, director of translational neuroscience at the DMCBH; and Ravi Rungta, then a graduate student in the MacVicar lab and the lead author of the Cell article that reveals the findings, developed several novel technological approaches to identify the cascade of events that took place within individual brain cells as they swelled. They then switched off the expression of different genes and were able to pinpoint a single protein (SLC26A11) that acts as a channel for chloride to enter nerve cells. By turning off the chloride channel, the accumulation of fluid into the cells was halted, and nerve cells no longer died.
The Cell article is entitled “The cellular mechanisms of neuronal swelling underlying cytotoxic edema.” The research was co-sponsored by the Canadian Institutes of Health Research, Brain Canada, Genome British Columbia, the Michael Smith Foundation for Health Research, and the Koerner Foundation.