Nutrition scientists in the Military Nutrition Division at the U.S. Army Research Institute of Environmental Medicine (USARIEM) are conducting animal studies to examine various nutritional interventions that may increase resilience to blast injury.

In 2010, USARIEM demonstrated that dietary zinc supplementation provided behavioral resiliency in a rat model of traumatic brain injury (TBI). Using a closed-head wound model, rats were provided diets of varying zinc content for four weeks before being exposed to a mild traumatic brain injury (mTBI). In the recovery period, the Institute monitored various indices of behavioral health (anxiety, depression, memory and learning) and showed that rats kept on the low zinc diets did not recover as well as the rats fed the adequate zinc, or supplemental zinc during recovery. These data suggest a role for supplemental zinc in preventing cognitive and behavioral deficits after TBI. USARIEM is now performing proteomic analyses of brain tissues to better understand the mechanism(s) of diet-induced repair.

In planned follow-up studies, USARIEM will use similar diets and animals, but the TBI-model will change to a blast-overpressure model, mimicking what Soldiers experience when exposed to improvised explosive device (IED)-like blasts. The goal is to see if the dietary protection provided by the zinc-supplemented diets to our rats exposed to a projectile-injury (non-blast injury) will also be of benefit to animals exposed to an IED-like blast injury.

In addition to manipulating dietary zinc levels, USARIEM will also examine how pre-treatment with dietary omega-3 fatty acids (found in cold water fish) may limit mTBI-induced cell damage and edema, thus enhance recovery in the rat model. In addition, USARIEM will introduce physiological stressors (e.g., sleep deprivation) prior to the head injury, which the Institute predicts will exacerbate edema formation and slow recovery. As both dietary omega-3s and zinc cross the blood-brain barrier, USARIEM predicts that neuronal death associated with mTBI will be reduced in rats receiving supplementation.

USARIEM's objective is to screen a variety of nutritional interventions for their potential to increase resilience to mTBI.

For more information, visit http://www.usariem.army.mil.