Figure 4.
miR-199a-5p inhibitor mediates protection against OGD/R-induced injury by upregulating the expression of HIF-1α and p-GSK3β. (A) Analysis of HIF-1α levels and the relative p-GSK3β/GSK3β protein ratio in H9c2 cells transfected with si-NC or si-HIF-1α. *P<0.05 vs. si-NC. (B) H9c2 cells were treated with OGD/R and transfected with miR-199a-5p inhibitor in the presence or absence of si-HIF-1α. The cell lysates were analyzed by western blotting for GSK3β and p-GSK3β; expression was quantified by ImageJ software and normalized to β-actin. *P<0.05 vs. si-NC. (C) Apoptosis and (D) ΔΨm were analyzed by TUNEL and flow cytometry analyses, respectively. *P<0.05, **P<0.01. (E) OGD/R-treated H9c2 cells were transfected with miR-199a-5p inhibitor in the presence or absence of LiCl. The cell lysates were analyzed by western blotting for GSK3β and p-GSK3β; expression was quantified by ImageJ software and normalized to β-actin. *P<0.05, **P<0.01 vs. SC. (F) Apoptosis and (G) ΔΨm were analyzed by TUNEL and flow cytometry analyses, respectively. *P<0.05, **P<0.01. Data are presented as the mean ± standard deviation of four independent experiments. HIF-1α, hypoxia-inducible factor-1α; p-, phosphorylated; GSK3β, glycogen synthase kinase 3β; si-, short interfering RNA; NC, negative control; OGD/R, oxygen-glucose deprivation and reperfusion; miR-199a-5p, microRNA-199a-5p; ΔΨm, mitochondrial membrane potential; SC, scrambled control.