What we have yet to learn about traumatic brain injuries (TBIs)
March is Brain Injury Awareness Month. And while medical advancements have led to more options for those who experience a traumatic brain injury (TBI), treatments are lacking.
According to a 2013 study published in the NIH’s National Center for Biotechnology Information, approximately 1.7 million people in the U.S. are afflicted with a TBI each year, and one-third of all injury-related deaths list TBI as a contributing cause.
Despite the frequent occurrence, TBI treatment options are not abundant because human brains are hard to replicate, and therefore study, in a laboratory.
“Traumatic brain injury research is hard because animal models don’t easily translate to the human condition very well,” said Dr. Matthew Rasband, a molecular neurobiologist and professor of neuroscience at Baylor College of Medicine. “You have to think about the differences in size of the rodent head and human head. The impacts and injuries are different and difficult to model in a mouse.”
What researchers do is try to understand the underlying mechanisms that lead to brain injuries, which also may be observed in spinal cord injuries or stroke. Rasband said it’s common for researchers to learn about TBIs from spinal cord studies and vice versa.
Brain injuries can range from concussions to severe dramatic head injuries that may result in destruction of the brain. TBI research expanded following the Gulf War and the wars in Iraq and Afghanistan, and Rasband was part of a team of researchers looking into blast-induced TBIs.
“In my lab, we were trying to understand subcellular domains that are important for generating electrical signals and how they are affected by blasts,” he said. “It’s clear that mild TBIs can predispose (people) to neurodegenerative problems, like Alzheimer’s disease.”
This predisposition to neurodegenerative problems can be seen in football players, boxers and other athletes who take regular hits to the head, regardless of intensity. Athletes who have repeated concussions may develop Parkinson’s disease, which causes the death of neurons in the brain which are responsible for neural control.
A major challenge with mild TBIs is that injuries may not be detected when using a typical CT scan, Rasband said. Researchers now are working to develop behavioral or serum biomarkers that will indicate an injury to neurons.
“I would emphasize that TBIs are incredibly complicated,” he said. “They involve neurons, vasculature, all kinds of cell types in the brain, which can result in inflammation, so this complex mix of biological responses is what makes it so hard to find treatments and solutions for individuals who have suffered these injuries. It takes an entire community to peel apart different aspects of injury response – it’s a big challenge.”
Brain research can be conducted postmortem, but it’s mostly imaging (CT scans) and there is no way to manipulate the brain at that point, he added.
One area Rasband hopes will progress soon is the development of neuroprotective medications to use on a person who recently e a concussion or brain injury.
“We don’t have any that target neurons that save them or allow them to be more resilient,” he said. “We still don’t know the mechanisms that cause neurons to be injured, die or regenerate. These are active areas of research.”
By Julie Garcia
