Concussive injuries induce neuronal stress-dependent tau mislocalization to dendritic spines with acrolein and functional network alteration in TBI-on-a-chip.

Abstract

Traumatic brain injuries (TBIs) are a risk factor for Alzheimer's disease (AD), and share several important pathological features including the development of neurofibrillary tangles (NFT) of tau protein. While this association is well established, the underlying pathogenesis is poorly defined and current treatment options remain limited, necessitating novel methods and approaches. In response we developed "TBI-on-a-chip", an <i>in vitro</i> trauma model utilizing murine cortical networks on microelectrode arrays (MEAs), capable of reproducing clinically relevant impact injuries while providing simultaneous morphological and electrophysiological readout. Here, we incorporate a digital twin of the TBI-on-a-chip model to resolve cell-scale mechanical deformation <i>via</i> shear stresses and demonstrate direct connections between impact forces with aberrations in tau and synaptic deficits, and correlate these changes with elevations of oxidative stress, a suspected key contributor to both trauma and neurodegeneration. This multi-disciplinary investigation combines computational modeling, electrophysiology, and imaging, to explore tau mislocalization and functional deficits as a function of force, in the context of a potential mechanism <i>via</i> acrolein. We hope that this novel, integrative approach will help improve our mechanistic understanding of trauma and neurodegeneration, solo and in concert, and ultimately assist in generating more effective treatment options.