EGCG inhibited the levels of miR-29b-3p, MMP-13 and IL-6β but promoted cell viability in IL-1β-stimulated CHON-001 cells by the down-regulation of miR-29b-3p. (A) CHON-001 cells were divided into control, MC, M, MC + E50 and M + E50 groups. (B–E) CHON-001 cells were divided into control, IL-1β, MC, M, MC + IL-1β, M + IL-1β, MC + IL-1β + E50 and M + IL-1β + E50 groups. (A, B) The level of miR-29b-3p was determined by qRT-PCR in CHON-001 cells. (C) Cell counting kit-8 (CCK-8) indicated cell viability in CHON-001 cells. (D, E) The levels of MMP-13 and IL-6 were determined by ELISA in CHON-001 cells. U6 was used as a reference gene for miRNA. EGCG: epigallocatechin-3-O-gallate; E50: 50 μM EGCG; MC: mimics control; M: miR-29b-3p mimics; qRT-PCR: real-time reverse transcription polymerase chain reaction; control: CHON-001 cells cultured without IL-1β or EGCG. ΔΔΔp < 0.001 vs. control; **p < 0.01 or ***p < 0.001 vs. MC; †††p < 0.001 vs. M; ∧∧p < 0.001 vs. M + IL-1β. All measurements were performed at least three times. Data were presented as the means ± standard deviation (SD).