Sikokianin A from Wikstroemia indica protects PC12 cells against OGD/R-induced injury via inhibiting oxidative stress and activating Nrf2.

Ischemic cerebral stroke is a severe cause of human death and disability. Natural products play an important role in the discovery of novel therapy for cerebral ischemia. Herein, we investigate the neuroprotective effects of sikokianin A identifiedfrom Wikstroemia indica using PC12 cell exposed to OGD/R. The results revealed sikokianin A can improve the poor viability and release of intracellular LDH in PC12 cells induced by OGD/R. Further studies have demonstrated the increased ROS and MDA together with reduced SOD activity were attenuated by sikokianin A. Meanwhile, decreased mitochondrial membrane potential, activated Caspase-3, down-regulated Bcl-2 and up-regulated Bax were reversed. These results indicate the protective effects of sikokianin A are associated with inhibiting oxidative stress and apoptosis resulting from OGD/R. Additionally, sikokianin A can activate Nrf2 and downstream HO-1 in PC12 cells treated by OGD/R, which implied Nrf2/HO-1 signaling pathway was involved in the protective effects of sikokianin A.