Overexpression of α-synuclein in SH-SY5Y cells in vitro leads to oxidative stress

AIM: To observe the influence of overexpression of α-synuclein on the cultured SH-SY5Y cells. METHODS: The plasmid of α-synuclein-pcDNA3 was transfected into SH-SY5Y cells with LipofectAMINE. The expression of α-synuclein was determined by anti-α-synuclein immunocytochemistry. The intracellular reactive oxygen species was determined with 2', 7'-dichlorofluorescein diacetate (DCF-DA) by using a FACSCAN flow cytometer and fluorescent microscope. The intracellular content of reduced GSH was detected with glutathione assay kit by spectrophotometer. RESULTS: The α-synuclein was expressed in cultured SH-SY5Y cells transfected with the plasmid of α-synuclein-pcDNA3. The DCF loading analysis and the intracellular level of reduced GSH suggested that the transfected cells were under oxidative stress. CONCLUSION: Overexpression and accumulation of α-synuclein in SH-SY5Y cells increase intracellular reactive oxygen species levels, it is suggested therefore that the α-synuclein does play an important role in the pathogenesis of Parkinson's disease.