Dl-3n-butylphthalide improves traumatic brain injury recovery via inhibiting autophagy-induced blood-brain barrier disruption and cell apoptosis.

Blood-brain barrier (BBB) disruption and neuronal apoptosis are important pathophysiological processes after traumatic brain injury (TBI). In clinical stroke, Dl-3n-butylphthalide (Dl-NBP) has a neuroprotective effect with anti-inflammatory, anti-oxidative, anti-apoptotic and mitochondrion-protective functions. However, the effect and molecular mechanism of Dl-NBP for TBI need to be further investigated. Here, we had used an animal model of TBI and SH-SY5Y/human brain microvascular endothelial cells to explore it. We found that Dl-NBP administration exerts a neuroprotective effect in TBI/OGD and BBB disorder, which up-regulates the expression of tight junction proteins and promotes neuronal survival via inhibiting mitochondrial apoptosis. The expressions of autophagy-related proteins, including ATG7, Beclin1 and LC3II, were significantly increased after TBI/OGD, and which were reversed by Dl-NBP treatment both in vivo and in vitro. Moreover, rapamycin treatment had abolished the effect of Dl-NBP for TBI recovery. Collectively, our current studies indicate that Dl-NBP treatment improved locomotor functional recovery after TBI by inhibiting the activation of autophagy and consequently blocking the junction protein loss and neuronal apoptosis. Dl-NBP, as an anti-inflammatory and anti-oxidative drug, may act as an effective strategy for TBI recovery.