PEMBROKE — A lead team of experts at UNC Pembroke in collaboration with U.S. Army Research Laboratory and National Institutes of Health scientists authored a study that set out to understand how shockwaves from explosives may lead to an increased risk of Alzheimer’s disease, published by a premier brain research journal.
Directed by renowned neuroscientist Ben Bahr, the research article “Distinct and Dementia-Related Synaptopathy in the Hippocampus after Military Blast Exposures” has been published in Brain Pathology, the official medical journal of the International Society of Neuropathology.
“Studies linking blast exposures and TBI, even mild TBI, to an increased risk of Alzheimer’s disease are numerous,” said Dr. Bahr, the William C. Friday Distinguished Professor of Molecular Biology and Biochemistry. Bahr is among the upper 2% of world scientists for citations in their main subfield, according to a recent report from Stanford University, SciTech Strategies, and Elsevier Research Intelligence. His listing is within the top 1% of the many researchers in the study’s database.
“Shockwaves produced by military explosives, which have been linked to enhanced dementia risk, cause selective reductions among synaptic markers in circuitries of the hippocampus, and a sharp decline in synaptic functionality corresponded with the reduced immunolabeling of synapses,” Bahr continued.
“Explosive blasts account for a majority of the injuries among wounded service members, as hundreds of thousands of veterans from wars of the last 20 years are estimated to have experienced brain injuries caused by military or improvised explosives.”
An international panel of experts indicates the numbers of blast-exposed individuals returning from war zones with no detectable physical injury or neuropathology, but who still suffer from persistent neurological symptoms, including depression, headaches, irritability and memory problems.
“The mystery behind blast-induced neurological complications when traumatic damage is undetected may be rooted in distinct alterations to the tiny connections in the part of the brain particularly involved in memory encoding and social behavior, this region called the hippocampus,” Bahr said.
Bahr’s team tested slices of rat hippocampus and exposed the healthy tissue to controlled military blast waves. In the experimental brain explants, the rapid blast waves produced by the detonated military explosives led to selective reductions in components of brain connections needed for memory, and the distinct electrical activity from those neuronal connections was sharply diminished.
The study concluded that early detection of measurable deterioration may lead to vital improvements in diagnoses, the treatment of recurring neuropsychiatric impediments, and reducing the risk of developing dementia later in life, as the increased risk is likely rooted in the disruption of neuronal communication instigated by blast exposures.
“Blasts can lead to debilitating neurological and psychological damage, but the underlying injury mechanisms are not well understood,” said Dr. Frederick Gregory, program manager of the Army Research Office.
“Understanding the molecular pathophysiology of blast-induced brain injury and potential impacts on long-term brain health is extremely important to understand in order to protect the lifelong health and well-being of our service members.”
Bahr served as principal investigator for the project. He credits Michael Almeida, a research specialist and lab manager at the UNCP Biotechnology Center, with conducting the majority of the work on the study. A PhD student at UNC Wilmington conducting research in the Biotechnology Center, Almeida is the first student to conduct an entire PhD project on UNCP’s campus.
The other authors were Dr. Thuvan Piehler of the U.S. Army Research Lab in Maryland; Drs. Kelly Carstens, Meilan Zhao, and Mahsa Samadi led by Professor Serena Dudek at the National Institute of Environmental Health Sciences in North Carolina; Christopher Norton, a 2018 UNCP graduate who worked in the Bahr Lab; and UNCP faculty members Catherine Parisian and Karen Farizatto who contributed their expertise to the publication.
