Overexpression of 14-3-3 protein alleviates the toxicity of MPP~+ to PC12 cell

Objective To investigate the protective effects of the 14-3-3 protein overexpression on the injury of PC12 cell induced by MPP~+ and its mechanisms.Methods For expression in mammalial cells, pcDNA3.1(+)-14-3-3 plasmid was constructed and transfeeted into PC12 cell with Lipofectamine~(TM)2000. The overexpression of transfected 14-3-3 gene in PC12 cell was determined by immunofluorescence and Western blotting.The effects of 14-3-3 overexpressing on the cells viability,apoptotie ratio and the activity of superoxide dismutase(SOD)as well as glutathione peroxidase(GSH-Px)of PC 12 cell treated with MPP~+ were measured by MTT assay,flow cytometry analysis and microplate reader respectively.Results The expression of 14-3-3 protein in transfection group(1.19±0.06)increased evidently compared with control group(0.75±0.05).And the antioxidant enzyme activity assession,MTT assay and flow cytometry analysis shows that the overexpression of 14-3-3 protein elevates the activity of SOD(transfection group:(9.13± 0.41)U/mg protein,MPP~+ group:(6.45±0.52)U/mg protein)and GSH-Px(transfection group: (89.66±3.42)μmol/mg,protein MPP~+ group:(82.73±4.15)μmol/mg protein),increases the cell viability(transfection group:0.78±0.06,MPP~+ group:0.54±0.07),and inhibits cell apoptosis (transfeetion group:11.87%±3.26%,MPP~+ group:36.30%±2.39%)of PC12 induced by MPP~. Conclusion The overexpression of 14-3-3 protein could elevate the activity of antioxidant enzymes SOD and GSH-Px,reduce oxidant stress,alleviate MPP~+ toxicity,and thus inhibit the apoptosis of PC12 cell induced by MPP~+.