Brain injuries can have a huge impact on both your brain and your body. But, new research suggests brain injuries can be felt on an even deeper level too.
According to new findings published this week in EBioMedicine, brain injuries also affect hundreds of genes linked to an increased risk for a wide range of issues such as Alzheimer’s disease, Parkinson’s disease, post-traumatic stress disorder, and depression.
The researchers from UCLA’s Institute for Quantitative and Computational Biosciences say they have identified so-called “master genes” which they believe control hundreds of other genes in the brain. They also say these genes are damaged after a brain injury, potentially contributing to the increased risk for neurological and psychiatric disorders after TBI.
“We believe these master genes are responsible for traumatic brain injury adversely triggering changes in many other genes,” said Xia Yang, a senior author of the study and a UCLA associate professor of integrative biology and physiology.
As the scientists explain, genes have the potential to become any of numerous forms of proteins. But, when “master genes” are damaged, they can do damage to other related genes.
While the team says they have identified the master genes affected by brain injury, there are a few ways the process may be actually occurring.
The first possibility is that injury causes genes to produce abnormal proteins, such as the amyloid plaques found in Alzheimer’s disease. Yang also says injury may change the number of expressed genes in each cell, which could also contribute to issues.
“Very little is known about how people with brain trauma — like football players and soldiers — develop neurological disorders later in life,” said Fernando Gomez-Pinilla, a UCLA professor of neurosurgery and of integrative biology and physiology, and co-senior author of the new study. “We hope to learn much more about how this occurs.”
For the study, the team trained 20 healthy rats to escape from a maze. Then, they produced a concussion-like brain injury in half of the rats. When placed back into the maze, the team says the injured rats took approximately 25% longer than those that were un-injured.
To examine how the rats’ genes had been affected, the researchers then drew RNA samples from the brains of five rats in each group.
According to the report, the injured rats showed alterations in a core group of 268 genes in the hippocampus, and 1,215 altered leukocytes.
“A surprise was how many major changes occurred to genes in the blood cells,” Yang said. “The changes in the brain were less surprising. It’s such a critical region, so it makes sense that when it’s damaged, it signals to the body that it’s under attack.”
The researchers say they believe the findings could support the possibility of creating a gene-based test for identifying those who have experienced concussions.
Over 100 of the genes altered by brain injury have been associated with neurological and psychiatric disorders in humans. For example, 16 of the genes affected in the rats have direct analogs in humans. Those genes have also been specifically linked to a heightened risk for Alzheimer’s.
Moving forward, the team plans to further investigate the master genes to determine if repairing or modifying them also leads to positive changes in large numbers of other genes. If so, this would suggest master genes could be key to future long-term and preventative treatments after TBI.