Traumatic brain injury is called the “signature injury” for veterans coming back from tours in Iraq and Afghanistan. It is estimated by the Rand Corporation that 320,000 of the soldiers returning have struggled with significant neurological issues, such as memory loss and anxiety, even though they show no physical signs of brain injury.
Now, Chemical & Engineering News reports that researchers believe they have identified a possible chemical signature for people who are at a risk of developing neurological disorders after a bomb blast. Levels of a lipid called ganglioside GM2 spike in the brains of mice exposed to mild explosions, and the researchers believe it may able to act as a biomarker.
Physical signs of brain damage from large explosions are usually able to be seen by doctors, but mild blasts don’t consistently create noticeable injuries. Hoping to understand the way smaller blasts affect the brain, Amina S. Woods from the National Institute on Drug Abuse exposed groups of mice to the blast from a small bomb. After the explosions, none of the mice showed physical injuries in the brain.
After the blast, Woods and her team found that the lipid ganglioside GM2 spiked, especially in the hippocampus, thalamus, and hypothalamus. Gangliosides are molecules containing sugars and lipids, and the mice closest to the explosion showed the highest amounts of ganglioside GM2. The heightened amounts of the ganglioside were seen in the brains 24 hours after the blast, but had returned to normal levels at 72 hours.
Ganglioside GM2 is most often associated with Tay-Sachs disease, and Woods noticed the symptoms of late-onset Tay-Sachs exactly mirror the symptoms soldiers have been reporting after being hit with a mild blast. The next step is to examine the connection these lipids have with traumatic brain injury.