DONG, L.-G., LU, F.-F., ZU, J., ZHANG, W., XU, C.-Y., JIN, G.-L., YANG, X.-X., XIAO, Q.-H., CUI, C.-C., XU, R., ZHOU, S., ZHU, J.-N., SHEN, T., and CUI, G.-Y.
OBJECTIVE: The aim of this study was to explore the effect of micro ribonucleic acid (miR)-133b on 1-methyl-4-phenylpyridinium ion (MPP+)-induced apoptosis in the Parkinson’s disease (PD) model. MATERIALS AND METHODS: PC12 cells were induced by different concentrations of MPP+ to establish the PD cell model. Subsequently, the survival rate of PC12 cells was detected using Cell Counting Kit-8 (CCK-8) assay. Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) was used to detect the expression of miR-133b in the PD model induced by different concentrations of MPP+. Next, PC12 cells were transfected with miR-133b mimic and miR-negative control (NC), and divided into MPP+ group, MPP+ + miR-NC group and MPP+ + miR-133b mimic group. Transfection efficiency was verified using qRT-PCR. The apoptosis of cells was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Moreover, the expressions of extracellular signal-regulated kinase 1/2 (ERK1/2) and phosphorylated (p)-ERK1/2 were determined using Western blotting. RESULTS: After MPP+ treatment, the survival rate of PC12 cells significantly declined (p<0.05). MPP+ exhibited toxicity against PC12 cells in a concentration-dependent manner. Meanwhile, cell survival rate decreased remarkably with the increase of MPP+ concentration (p<0.05). With increased concentration of MPP+, the expression of miR-133b in the PD cell model declined significantly (p<0.05). The apoptosis of PC12 cells was remarkably inhibited by overexpression of miR-133b in the PD cell model (p<0.05). In addition, the protein expression of p-ERK1/2 in PC12 cells was notably reduced after overexpression of miR-133b in the PD cell model (p<0.05). CONCLUSIONS: MiR-133b is lowly expressed in the PD cell model. Furthermore, overexpression of miR-133b inhibits cell apoptosis in the PD cell model by regulating the ERK1/2 signaling pathway. [ABSTRACT FROM AUTHOR]