Fig. 6

BMSC-derived EVs loaded with miR-15b induce osteogenic differentiation of BMSCs by inactivating the KLF2-dependent NF-κB signaling pathway via targeting WWP1. BMSCs were co-cultured with inhibitor NC, EV-inhibitor NC, or EV-miR-15b inhibitor. a, b ALP activity in BMSCs (× 200). c, d The expression of WWP1, KLF2, Runx2, OPN, and OCN in BMSCs with osteogenic differentiation for 14 days assessed by Western blot analysis normalized to GAPDH. e The mineralization of BMSCs determined using ARS staining after treatment with hMSCs + inhibitor-NC, hMSCs + EV + inhibitor-NC, hMSCs + EV + inhibitor-NC, or hMSCs + EV + miR-15b inhibitor (× 200). *p < 0.05 vs. hMSCs + inhibitor-NC; ^#p < 0.05 vs. hMSCs + EV + inhibitor-NC. f NF-κB activity in BMSCs evaluated by dual-luciferase reporter assay. *p < 0.05 vs. BMSCs treated with inhibitor NC. ^#p < 0.05 vs. BMSCs treated with EV-inhibitor NC. The measurement data were shown as mean ± standard deviation and compared by one-way ANOVA, followed by Tukey’s post hoc test. The cell experiment was repeated three times