Protective effect of NAD(P)H:quinone oxidoreductase 1 on dopaminergic cells

AIM: To determine the influence of NAD(P)H:quinone oxidoreductase 1 (NQO1) on dopamine-induced toxicity in dopaminergic cells.METHODS: MTT assay was used to determine the toxic curve of dopamine in SH-SY5Y cells. Lipofection was applied to transfect SH-SY5Y cells with an NQO1 expression plasmid. The endogenous and transfected NQO1 expression was detected by immunofluorescence staining and Western blotting. The content of cellular quinone protein was measured by nitroblue tetrazolium (NBT) method. RESULTS: Dopamine reduced SH-SY5Y cell proliferation in a dose-dependent manner, which was correlated with an increase in the content of quinone protein. Increased expression of NQO1 by transient transfection or by phase II enzyme inducer sulforaphane treatment alleviated dopamine-induced toxicity and reduced the content of cellular quinone protein. CONCLUSION: Increased NQO1 expression protects SH-SY5Y cells against cytotoxicity caused by dopamine.