TP53 and injury: Neuronal loss (NeuN), an increase neuronal apoptosis (BID), and an elevation in astrocyte number (GFAP) were evident in both brain regions, which is in accord with prior studies in this mTBI model describing elevations in apoptotic proteins (p53, c-Jun, and Bcl-2) as well as TUNEL-positive and silver stain-impregnated degenerating neurons [82,84], as well as other animal models of brain injury [20,60,85,86].