WHEN NOXIOUS EXPOSURE MEETS INJURY: HEAVY METALS WORSEN OUTCOMES AFTER BRAIN INJURY

Traumatic brain injury (TBI) is a significant risk factor for the development of neurodegenerative diseases. Simultaneously, chronic exposure to heavy metals represents another major contributor to neurodegeneration, as populations worldwide are continuously exposed to heavy metals through food, water, and the environment. Both insults are associated with neuroinflammation, oxidative stress, and potential disruption of cellular processes. However, their combined effects have never been investigated. To address this critical gap, this project aims to explore how chronic heavy metal pre-exposure exacerbates functional outcomes, cognitive deficits, and histopathological damage following repeated mild TBI in mice. Preliminary findings demonstrate evident accumulation of environmentally relevant heavy metals, predominantly arsenic, chromium, and lead in brain tissue. This accumulation is accompanied by measurable impairments in motor coordination and balance in mice as well as deficits in spatial working memory and decision-making processes. Together, these results support the concept that chronic environmental metal exposure sensitizes the brain to injury and may accelerate neurodegenerative processes. This work establishes a biologically relevant framework for studying environmentally driven brain vulnerability and underscores the importance of incorporating environmental exposure history into models of traumatic brain injury and neurodegeneration.