Ruscogenin regulates endogenous antioxidation in dopamine neurons by activating Keap1/Nrf2/HO-1 pathway

Purpose: To investigate the effect of ruscogenin (RUS) on cell viability, lipid peroxidation and mitochondrial dysfunction in a Parkinson's disease (PD) model.Methods: The neuroblastoma cell line SH-SY5Y was modified with 1-methyl-4-phenylpyridine (MPP+) to establish a PD model. RUS (1 or 10 mu M) was used to treat MPP+ induced SH-SY5Y cells. Cell viability was assessed using CCK-8 assay. The concentrations of lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT) and glutathione peroxidase (GPx) were determined by enzyme-linked immunosorbent assay (ELISA). ATP production, Ca2+ concentration and JC-1 were quantified using commercial kits. The expression levels of tyrosine hydroxylase (TH), Keap1, Nrf2 and HO-1 were evaluated by western blot analysis.Results: RUS protected cell viability, reduced LDH production, and elevated TH expression in MPP+- modified SH-SY5Y cells. RUS promoted the release of SOD, CAT and GPx, but suppressed MDA production. Furthermore, RUS enhanced ATP metabolism, decreased Ca2+ leakage and maintained mitochondrial function. RUS also repressed Keap1 expression but increased Nrf2 and HO-1 levels. Conclusion: RUS enhances cell viability while alleviating cytotoxicity, lipid peroxidation and mitochondrial dysfunction in dopamine neurons through the activation of Keap1/Nrf2/HO-1 signaling pathway. Thus, RUS is a promising therapeutic candidate for PD treatment.