Research shows potential for brain injury urine test

About 10% of all wounded soldiers suffer from a blast-induced traumatic brain injury—many of whom are initially undiagnosed, because they don’t display obvious symptoms like motor impairment until months after the injury. But new research out of Purdue University may lead to an easy way to detect this kind of injury—through a simple urine test.

When an explosion occurs, most injuries are an immediate result of the shock wave created by the blast. However, secondary damage can happen too, in the days and weeks following. “Many times they don’t even realize they’ve been injured, and this is particularly alarming because these injuries have been linked to severe long-term psychiatric and degenerative neurological dysfunction,” said Riyi Shi, a professor in the basic medical sciences department and school of biomedical engineering at Purdue University, in a press release.

“The underlying mechanisms of injury remain poorly understood, impeding development of diagnostic and treatment strategies.”

Modeling with animals

In order to unearth some of this process (for the sake of finding a way to detect it), the research team used rats as their animal model. The rats were exposed to blasts wearing body shielding in order to simulate military body armor on soldiers.

Afterwards, examinations revealed evidence of brain inflammation—an indicator that ongoing damage may be occurring. However, the rats did not show signs of injury; their motor skills and short-term memory were unaffected.

“We detected structural and biochemical brain damage without obvious motor or cognitive deficits,” Shi says. “These findings highlight the difficulty and importance of early detection, indicating missed early diagnosis and subsequent lack of intervention could lead to serious long-term consequences.”

The animals also had elevated levels of acrolein—a neurotoxin that appears after brain cells become damaged, and which contributes to further damage. In the rats, levels of acrolein were three times higher than normal on the first day, and remained elevated five days later.

Testing with urine

Because of this, the team believes the presence of acrolein can indicate brain trauma without symptoms of injury. Even better, they discovered that detection involves a simple urine test. Further, the damage incurred by acrolein on the brain might be mitigated by a common blood pressure medication known as hydralazine. Hydralazine reduces the concentration of acrolein, leaving less of it around to cause damage.

Shi, who is attempting to develop a low-dose version of hydralazine for brain injuries, emphasized how important these results are. “Early detection and intervention could potentially mitigate or prevent delayed onset development of significant neurological dysfunction.”

The study is published in the Journal of Neurosurgery.

—–

Image credit: Thinkstock