Figure 5. Inhibition of miR-219a-2-3p in exosomes reduced the protective effects of IGF-Exo. (A) Luciferase activity was detected in PC12 cells co-transfected with pGL3 vector, pGL3-YY1, miR-219a-2-3p mimics, or miR-219a-2-3p mutant. (B) Relative YY1 expression after upregulation of miR-219a-2-3p measured by qRT-PCR. B) PC12 cells were transfected with miR-219a-2-3p mimics or miR-NC; relative YY1 expression was analyzed by qRT-PCR. (C) PC12 cells were transfected with Anti-miR-219a-2-3p (miR-219a-2-3p inhibitor) or Anti-NC (control); relative YY1 expression was analyzed by qRT-PCR. (D) Morphology in each experimental group examined by light microscopy (control group: PC12 cells without treatment; H2O2 group: PC12 cells treated with H2O2 for 24h; IGF-Exo group: PC12 cells pretreated with IGF-Exo for 24h followed by H2O2 for 24h); Anti-miR-219a-2-3p-IGF-Exo group: PC12 cells pretreated with miR-219a-2-3p inhibitor-transfected IGF-Exo for 24h followed by H2O2 for 24h). (E) Cell viability in each experimental group when miR-219a-2-3p was downregulated in IGF-Exo; (F) TUNEL staining (red) indicative of apoptosis in each experimental group; DAPI in blue. (G) Numbers of TUNEL-positive cells per field for each experiment group. (H–J) Western Blot analysis of YY1 and NF-kB-p65 (si-NC: siRNA blank vector; miR-NC: miRNA blank vector; si-YY1: YY1 siRNA; miR-219a-2-3p: miR-219a-2-3p mimics). Data are expressed as means ± SD (analysis of variance followed by Student-Newman-Keuls post hoc test). **P < 0.01, vs. control group; ##P < 0.01, vs. SCI group.