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Traumatic brain injury (TBI) leads to important and deleterious neuroinflammation, as evidenced by indicators such as edema, cytokine production, induction of nitric oxide synthase, and leukocyte infiltration. After TBI, cerebral vascular endothelial cells play a crucial role in the pathogenesis of inflammation. In our previous study, we proved that simvastatin could attenuate cerebral vascular endothelial inflammatory response in a rat traumatic brain injury. This purpose of this study was to determine whether simvastatin combined with an antioxidant could produce the same effect or greater and to examine affected surrogate biomarkers for the neuroinflammation after traumatic brain injury in rat. In our study, cortical contusions were induced, and the effect of acute and continuous treatment of simvastatin and vitamin C on behavior and inflammation in adult rats following experimental TBI was evaluated. The results demonstrated that simvastatin combined with an antioxidant could provide neuroprotection and it may be attributed to a dampening of cerebral vascular endothelial inflammatory response. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2010) 114, 237–246. Previously we demonstrated benefits of inhibiting the extracellular signal-regulated kinases 1/2 (ERK1/2) signaling pathway in spinal cord ischemia/reperfusion (I/R) injury. To further identify the underlying mechanisms, we investigated the impact of ERK inhibition on apoptosis and cellular protective mechanisms against cell death. Spinal cord I/R injury induced ERK1/2 phosphorylation, followed by neuronal loss through caspase 3-mediated apoptosis. Pre-treatment with U0126, a specific inhibitor of MAPK/ERK kinases 1/2 (MEK1/2), inhibited ERK1/2 phosphorylation, and significantly attenuated apoptosis and increased neuronal survival. MEK/ERK inhibition also induced I-κB phosphorylation and enhanced nuclear factor (NF)-κB/DNA binding activity, leading to expression of cellular inhibitors of apoptosis protein 2 (c-IAP2), a known nuclear factor-κB (NF-κB)-regulated endogenous anti-apoptotic molecule. Pyrrolidine dithiocarbamate, an NF-κB inhibitor, by blocking I-κB phosphorylation, NF-κB activation, and c-IAP2 synthesis, abolished the protective effects of U0126. The MEK/ERK pathway appears to mediate cellular death following I/R injury. The U0126 neuroprotection appears related to NF-κB-regulated transcriptional control of c-IAP2. MEK/ERK inhibition at the initial stage of I/R injury may cause changes in c-IAP2 gene expression or c-IAP2/caspase 3 interactions, resulting in long lasting therapeutic effects. Future research should focus on the possible cross-talk between the MEK/ERK pathway and the NF-κB transcriptional cascade. [ABSTRACT FROM AUTHOR]