Anti-inflammatory effect of hFCPC-Exo and miR-125b-5p on IL-1β signal pathways in chondrocytes. hFCPCs were used to produce an IL-1β-induced OA model in chondrocytes. hFCPCs were transfected with 100 pmol of synthetic miRNA mimic or anti-sense inhibitor of miR125b-5p for 24 h, followed by treatment with IL-1β (10 ng/mL) and/or hFCPC-Exo (10 µg/mL). A The expression of inflammation mediators (IL-1β, MMP13, and ADAMTS-5) was analyzed by RT-PCR. B The expression of cartilage-specific ECMs (ACAN and COL2A1) was analyzed by RT-PCR. In both A and B, data were normalized to GAPDH mRNA levels and presented as mean ± SD from 3 independent experiments (n = 3). Statistical significance was compared for untreated group versus IL-1β group, for IL-1β only group versus the other treatment groups (#), and for exosome group versus miRNA mimic or inhibitor group (*). +/#/*p < 0.05, and ++/**p < 0.01