Fig. 5.

BRD4 knockdown inhibited IL-1β-induced chondrocyte apoptosis and ECM degradation by suppressing the GREM1-NF-κB pathway (A–B) GREM1 expression level in IL-1β-treated chondrocytes following oe-NC or oe-GREM1 transfection was examined by qRT-PCR and Western blot. Both BRD4 knockdown and GREM1 overexpression were induced in IL-1β-treated human chondrocytes (C) CCK8 assay was employed to analyze chondrocyte viability (D) Chondrocyte apoptosis was assessed by TUNEL staining (E–F) GREM1, p-p65, Bax, Bcl-2, MMP13, ADAMTS5, Collagen II and Aggrecan protein levels in cells were detected using Western blot. Data were expressed as mean ± SD. All our data were obtained from three independent experiments. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001.