95923 TBI-on-a-chip: Linking physical impact to neurodegeneration by decrypting primary and secondary injury mechanisms

ABSTRACT IMPACT: This unique approach has the capability to elucidate the pathological mechanisms underlying traumatic brain injuries and neurodegeneration, both separately and in concert, while simultaneously providing a semi-high throughput model for investigating potential pharmaceutical interventions: discoveries that would have major translational implications and a significant impact worldwide. OBJECTIVES/GOALS: We aim to improve our understanding of the mechanisms behind the development of neurodegenerative diseases by utilizing the link between traumatic brain injuries and demonstrated biomarkers with our innovative TBI on a chip model. With this tool, we hope to provide new pathological insights and explore potential pharmaceutical interventions. METHODS/STUDY POPULATION: E16 murine cortical networks were cultured onto reusable, optically transparent MEAs (fabricated in-house), and subjected to a clinically-relevant range (30-300g) of impact g-forces, utilizing our exciting new in vitro model of trauma (TBI on a chip) with real-time electrophysiological and morphological access. Impacts were systematically applied at varying intensities, repetitions, and time points, and fixed 24-hours post. Basic immunocytochemical techniques were used to investigate post-impact levels of acrolein, an established biomarker of both post-TBI oxidative stress and neurodegeneration (ND), and compared to procedurally and age-matched non-impact control networks. In addition, several other TBI/ND biomarker investigations are in progress (βA42, α-synuclein, and phosphorylated tau). RESULTS/ANTICIPATED RESULTS: Impact experiments revealed significant, force-dependent increases of acrolein (acrolein-lysine adducts) at 24hrs post impact, indicative of impact-linked neuronal degeneration. These changes were amplified by the following manipulations: increasing g-force exposure (30-250 g); the rapid (4-6 sec interval) application of multiple impacts (1, 3, 5 and 10x); and exposure to 40 mM EtOH (10 min duration immediately following impact). Further, we demonstrate the enhancement of injury recovery as a function of: increasing time intervals between repeated hits; Hydralazine exposure. In addition, conditioned media from maximally-impacted cultures can cause acrolein elevation when introduced to non-impact, control networks, indicating acrolein’s role as a diffusive-factor in post-TBI secondary injuries. DISCUSSION/SIGNIFICANCE OF FINDINGS: This novel approach provides unprec