Peroxisome proliferator-activated receptor-gamma coactivator-1 β (PGC-1β) overexpression enhances proinflammatory cytokines, matrix metalloproteinases (MMPs) and receptor activator of nuclear factor-kappa B ligand (RANKL) production in rheumatoid arthritis (RA)-fibrolast-like synoviocytes (FLS). (A) After PGC-1β overexpression, the protein level of mitogen-activated protein kinases (MAPKs) in FLS was detected by western blot. (B) After PGC-1β overexpression, the proinflammatory cytokines, MMPs and RANKL mRNA expression in FLS was evaluated by qPCR. (C) After PGC-1β overexpression, the protein level of proinflammatory cytokines was examined by cytometric bead array, while the level of MMP-3, MMP-13 and RANKL was detected by western blot. The data are represented by mean ± SD from three independent experiments. *P < 0.05, **P <0.01, ***P <0.001.