Neuroprotective effects of salvianolic acid B against oxygen-glucose deprivation/reperfusion damage in primary rat cortical neurons

Background Cerebral ischemia-reperfusion injury is the main reason for the loss of neurons in the ischemic cerebrovascular disease. Therefore, to deeply understand its pathogenesis and find a new target is the key issue to be solved. This research aimed to investigate the neuroprotective effects of salvianolic acid B （SalB） against oxygen-glucose deprivation/reperfusion （OGD/RP） damage in primary rat cortical neurons.Methods The primary cultures of neonatal Wister rats were randomly divided into the control group, the OGD/RP group and the SalB-treatment group （10 mg/L）. The cell model was established by depriving of oxygen and glucose for 3 hours and reperfusion for 3 hours and 24 hours, respectively. The neuron viability was determined by MTT assay. The level of cellular reactive oxygen species （ROS） was detected by fluorescent labeling method and spin trapping technique respectively. The activities of neuronal Mn-superoxide dismutase （Mn-SOD）, catalase （CAT） and glutathione peroxidase （GSH-PX） were assayed by chromatometry. The mitochondria membrane potential （△ψm） was quantitatively analyzed by flow cytometry. The release rate of cytochrome c was detected by Western blotting. The neuronal ultrastructure was observed by transmission electron microscopy. Statistical significance was evaluated by analysis of variance （ANOVA）followed by Student-Newman-Keuls test.Results OGD/RP increased the level of cellular ROS, but decreased the cell viability and the activities of Mn-SOD, CAT and GSH-PX; SalB treatment significantly reduced the level of ROS （P ＜0.05）; and enhanced the cell viability （P ＜0.05）and the activities of these antioxidases （P ＜0.05）. Additionally, OGD/RP induced the fluorescence value of △ψm to diminish and the release rate of cytochrome c to rise notably; SalB markedly elevated the level of △ψm （P ＜0.01） and depressed the release rate of cytochrome c （P ＜0.05）; it also ameliorated the neuronal morphological injury.Conclusion The neuroprotection of SalB may be attributed to the elimination of ROS and the inhibition of apoptosis.