Researchers have identified a biological switch that shuts down brain swelling after a head injury or stroke. The discovery has widespread medical implications and could be valuable in reducing the risk to sportspeople after injury.
Turning off a single gene successfully stopped swelling in rodent brains, according to a team from the University of British Columbia and Vancouver Coastal Health.
The discovery opens up the possibility of a drug treatment to block brain damage after a head injury, heart attack, stroke or infection.
“This discovery is significant because it gives us a specific target,” said Dr Brian MacVicar, co-director of the centre where the study was conducted.
“Now we know what we are shooting at, we just need the ammunition.”
It has long been known that head trauma can cause a salt build up in brain tissues, which in turn draws in water to cause swelling in the days after injury. If the swelling becomes severe brain tissues can become squeezed, causing them to lose blood supply and die.
Dr MacVicar and colleagues identified the single gene and its protein, SLC26A11, that acts as the channel that brings salt into the nerve cells.
The team switched off this gene, and this stopped the accumulation of fluid in and halted damage to brain tissues. They publish their findings today in the journal Cell.
Scientists now have a target that might help them develop a treatment post-head injury. It will take some years to find and test a drug that can block the action of the protein.
Sports injuries
Concussion is a worry in many sports, but this usually does not cause the severe swelling seen in stroke or accident, according to Dr Noel McCaffrey, sports medicine consultant and lecturer in the School of Health and Human Performance in DCU.
Even so, tragic sports incidents can occur, such as the death of Australian cricketer Phillip Hughes, who died in November 2014 when struck in the head by a cricket ball.
Days later, cricket umpire and former Israel captain Hillel Oscar died after being hit by a ball.
These deaths were likely caused by bleeds into the brain which triggered swelling, Dr McCaffrey said.
Similar head trauma after a slip while skiing in 2009 caused the death of actress Natasha Richardson, wife of Irish actor Liam Neeson.
