It is summer now and we are all rushing to the nearest beach, river or lake. It helps us to cool down, but we can also try some extreme sports there, such as jumping to the water from some height. That can result in some injury and as a new study from Pharmacological Research of Milan and the University of Glasgow showed, brain injuries can result in an abnormal form of the dementia.
You really shouldn’t be jumping to the water – a lot of people get disabling injuries every year from not being careful in this way. Scientists say that brain injury is a leading cause of death and disability in young adults, but even relatively mild cases can result in some form of dementia, such as chronic traumatic encephalopathy. Scientists wanted to see how exactly mechanical brain injuries increase the risk of dementia and so they analysed brain specimens from patients surviving a year or more after a severe injury.
This analysis allowed scientists to see that even a single injury generates an abnormal amount of protein tau, which is associated to dementia. Tau protein at first remains in the site of the injury, but over time it starts spreading to different brain regions, which is similar to the spreading of prions (another protein, associated with Creutzfeldt–Jakob disease). Scientists performed additional experiments with mice to see how tau protein spreads and they noticed that over some time after a single severe injury tau proteins slowly spread through the brain, which causes memory deficits and neuronal damage. Dr Elisa Zanier, leader of the research, said that these findings provide “the first evidence for how a mechanical brain injury might evolve into chronic degenerative brain disease, including CTE”.
It is very important to stress the word “single”. A lot of people get hit in the head repeatedly a lot, especially if they are involved in some kind of combat sports. It is not a coincidence that CTE is more common between boxers and MMA fighters than in general population. More than 5 million people in Europe live with a physical and/or psychological disability due to moderate or severe traumatic brain injury. Researches like this could pave the road towards more effective therapies and prevention methods.
One of the observations that scientists made is that blocking tau propagation may have therapeutic effects. Of course, for now we don’t know how to achieve that and traumatic brain injuries are still treated with more conventional methods. However, understanding how tau protein spreads through the brain could help reducing the risk of dementia after brain injuries.
Source: University of Glasgow