TNF-α-induced p53 activation induces apoptosis in neurological injury

It was previously confirmed that the apoptotic and necrotic neurons are found during the acute post-traumatic period, suggesting the induction of apoptosis after traumatic brain injury (TBI). To further explore the involvement of apoptotic factors in TBI, an apoptosis antibody array was conducted to measure the alterations of apoptotic factors in rat brain cortex after TBI. As a result, the Neurological Severity Scale (NSS) scores after TBI were increased, and the cell morphology of the brain cortex was destructed with increased neuronal apoptosis. Furthermore, the caspase-3 activity was increased, and the apoptotic-related factors TNF-alpha and p53 were up-regulated in the brain cortex. More importantly, in vitro experiments demonstrated that down-regulation of TNF-alpha in oxygen-glucose deprivation/reoxygenation (OGD/R) cells increased cell viability and decreased apoptosis and the p53 expression. These results suggested the involvement of TNF-alpha-induced apoptotic signalling pathway by activating p53 in the molecular mechanism of neurological injury.