Mailuoning suppresses H2O2-induced cortical neuronal injury and correlates with increased catalase activity and inhibited oxidative stress function

BACKGROUND:Mailuoning,a Chinese herb,has been widely used in China to treat acute ischemic stroke,and the major component exhibits anti-oxidative effects.However,the precise anti-oxidation pathway remains uncertain.OBJECTIVE:To validate the protective effects of Mailuoning on H2O2-induced primary cortical neuron injury in embryonic mice.DESIGN,TIME AND SETTING:Comparative observation and in vitro experiments were performed at the Jiangsu Key Laboratory for Molecular Medicine from January 2008 to September 2009.MATERIALS:Mailuoning(Nanjing Jinling Medical Company,China),reactive oxygen species(ROS) kit(Beyotime Biotechnology,China),superoxide dismutase(SOD),Cu/Zn SOD kit,malondialdehyde(MDA) kits(Nanjing Jiancheng,China),mitochondrial membrane potential(GMS10013.1,GENMED,USA) and catalase activity assay kit(Beyotime Biotechnology,China) were utilized for the present study.METHODS:Mouse embryonic cortical neurons were isolated and cultured with culture medium containing H2O2(80 μmol/L) and/or Mailuoning(1.25 μg/mL) for 24 hours.MAIN OUTCOME MEASURES:Neuronal viability and death were detected by methyl thiazolyl tetrazdium and flow cytometry;ROS production was determined by flow cytometry;mitochondrial membrane potential was detected using fluorescent staining;SOD activity was detected using a modified nitroblue tetrazolium method;Cu/Zn SOD and catalase activity was detected by spectrophotometry;and MDA was determined using the lipid peroxidation method.RESULTS:H2O2 increased ROS production and MDA concentration(P < 0.05),and decreased mitochondrial membrane potential,SOD,Cu/Zn SOD and catalase activity(P < 0.05);the number of surviving neurons(P < 0.05) was also reduced.Mailuoning reversed these changes.CONCLUSION:Mailuoning protects H2O2-induced injury in cortical cells by inhibiting ROS and MDA,increasing depolarization of mitochondrial membrane,and enhancing SOD and catalase activity.