The Courier & Advertiser (Fife Edition)
Study links brain injury with onset of dementia
Scottish scientists say single trauma incident can trigger disease
Scottish scientists have discovered for the first time how a brain injury caused by a single sporting or car accident can develop years later into life-changing dementia.
The Glasgow University team of neuroscientists was headed by Dr Willie Stewart, who has campaigned for greater safety in rugby and football, and last year scanned the brain of former Premier League striker Alan Shearer.
In a “landmark” study published today they have shown how just a single traumatic brain injury can generate a defective form of a common neural protein that can spread through the brain.
The result is memory deficits, neuronal damage and even full-blown dementia.
Working with specialists in Italy the Glasgow team analysed brain specimens from patients surviving a year or more after a single, severe brain injury.
They looked for so-called “tau” proteins, which are abundant in human brain tissue, but when in a “defective” form are associated with progressive, degenerative brain disease
The team found deposits of abnormal tau proteins were “much more widespread” in brain-injured patients.
They found the same type of abnormal tau in injured mice, which, over time, spread from the site of injury.
Importantly, they also found abnormal tau protein injected into healthy mice then seemed to “seed” and spread.
Dr Stewart, who believes legendary West Bromwich striker Jeff Astle’s progressive brain damage was linked to trauma, said the findings could lead to new treatments.
He said yesterday: “One of the striking features when we look at the brains of people who’ve been exposed to brain injury is the abnormal deposition of tau.
“What we’ve never really understood is how you get from a single brain injury – such as being hit by a car, or repeated brain injury, such as participating in sport – through to a widespread degenerative brain disease and a brain filled with tau.
“The question has always been how does this happen?
“What we saw in mice was this protein spreading throughout the brain when we let them survive a number of months, and importantly when we took samples of these diseased brains from mice and injected them into mice who had never been exposed to brain injury those mice developed the same problems.
“So it appears this abnormal protein can ‘seed’ or spread through the brain. “It’s like a grain of sand in an oyster. “We need tau proteins for our brains to function, but they can become abnormally folded, and that abnormal protein can then transmit its abnormal shape to other tau proteins and generate this evolving pathology.
“If this spreading tau protein is part of what’s generating the late dementia, perhaps one way to try and prevent it – short of avoiding brain injury – might be to try to target that tau protein and stop it from spreading.It gives us a novel way of challenging dementia.”
In Europe, more than five million people live with moderate or severe traumatic brain injury.
Last year, in a separate study, a team guided by Dr Stewart produced a study which found that heading a modern-day football just 20 times causes brain impairment.