Protective effect of bilobalide against nitric oxide-induced neurotoxicityin PC12 cells

AIM: To examine the effects of bilobalide on nitric oxide-induced neurotoxi city in pheochromocytoma-derived PC12 cells (PC12 cells). METHODS: PC12 cel l survival was monitored by LDH release and 3-(4, 5-dimethylthiazol-2-yl)-2 , 5-diphenyltetrazolium bromide (MTT) assays. Superoxide dismutases (SOD) a nd catalase (CAT) activities were measured based on their abilities to inhi bit the oxidation of epinephrine by the xanthine-xanthine oxidase system or to decompose H2O2 respectively. The content of malondialdehyde (MDA) was m easured by a fluorometric assay to indicate the lipid peroxidation. RESULTS : 3-Morpholinosydnonimine (SIN-1, 50 - 300 mu mol.L-1) induced PC12 cell da mage. After the cells had been pretreated with 10 mu mol.L-1 bilobalide for 24 h, the cell viability was increased to 91 % +/- 30 % from 52 % +/- 14 % in SIN-I alone group. Moreover, the activities of SOD and CAT were increas ed after cells were treated with bilobalide. CONCLUSION: The NO-induced neu rotoxicity can be protected by bilobalide in PC12 cells. The bilobalide-ind uced increase in SOD and CAT activities may serve as one of the mechanisms underlying the neuroprotective effect of bilobalide.