Effects of kinase inhibitors on the adiponectin-induced production of total NO (A), matrix metalloproteinase (MMP)-1 (B), MMP-3 (C), and MMP-13 (D) in osteoarthritis (OA) chondrocytes. AMPK and JNK inhibitors (20 μM compound C and SP6000125, respectively) significantly inhibited the production of total NO and all three MMPs (P < 0.05). NF-κB (inhibited by 100 μg/ml SN50) was involved in NO production, p38 MAP kinase (inhibited by 10 μM SB202190) in MMP-1 and -13, ERK (inhibited by 50 μM U0126) in MMP-3 and -13, and Akt kinase (inhibited by 50 μM LY294002) in MMP-13 expressions. Experiments were performed on four samples in duplicates. The histogram with error bars represents the mean and the standard error of the mean. The gray bars indicate significantly decreased total NO or MMP levels by Mann-Whitney U test (†P < 0.05).