Figure 4. XIST knockdown reduces MPP+-induced cellular damage by directly targeting miR-199a-3p. (A) Flow cytometry analysis of apoptosis was performed upon the silencing of XIST and/or miR-199a-3p. (B) Apoptotic cells in different groups were compared. (C) TUNEL staining was performed to evaluate cell apoptosis. (D) The viability of SH-SY5Y and PC-12 cells transfected or treated with the indicated molecules was evaluated by the CCK-8 assay. (E) The cell cycle phases were determined by propidium iodide staining and flow cytometry after the cells were treated with shXIST and/or miR-199a-3p inhibitor. (F) Comparison of the cell cycle results for the different groups. (G) Immunofluorescence staining of TUBB3 in MES23.5 cells is shown. (H) Western blot and (I) qPCR results showed that the inhibitory effects of shXIST on Sp1, LRRK2 and α-synuclein expression were counteracted by miR-199a-3p knockdown. The data are representative of three experiments. *p <0.05, **p <0.01 and ***p <0.001.