Effects of miR-101 on IL-1β-induced chondrocyte extracellular matrix (ECM) degradation. Primary rat chondrocytes were transfected with miR-Scr, miR-101 mimic, and miR-101 inhibitor, and then treated with or without IL-1β 12 h post-miRNA transfection. (A and B) The expression of collagen type II (A) and aggrecan (B) was evaluated by real-time PCR after transfection of miR-101 mimic or inhibitor with or without IL-1β treatment; n = 3, *P < 0.05. (C) The collagen type II expression of transfected chondrocytes was assessed by immunofluorescence staining method. Original magnification: × 60. Bars = 50 μm. (D) The fluorescence intensity of the images (C) was analyzed using Image-Pro Plus 6.0 software. Data are expressed as the average of at least five images; n = 3, *P < 0.05. (E) The sGAG content in the cell suspension was assessed by dimethylmethylene blue (DMMB) assay after transfection of miR-101 mimic or inhibitor with or without IL-1β treatment. Data were normalized by total protein content of the cell lysate in each group; n = 3, *P < 0.05.