A, Western blot analysis was used to detect the expression of MMP-8 at the protein level after RAW264.7 cells were stimulated for 24 h with different concentration gradients of visfatin (0, 0.5, 5, 50, and 500 ng/ml). B, Western blot analysis was used to detect the expression of MMP-8 at the protein level after RAW264.7 cells were stimulated with 500 ng/ml visfatin for different times (0, 3, 6, 12, 24 and 48 h). C, Real-time PCR was used to detect the expression of MMP-8 at the mRNA level after RAW264.7 cells were stimulated for 24 h with different concentration gradients of visfatin (0, 0.5, 5, 50, and 500 ng/ml). D, Real-time PCR was used to detect the mRNA expression of MMP-8 after RAW264.7 cells were stimulated with 500 ng/ml visfatin for different times (0, 3, 6, 12, 24 and 48 h). E, RAW264.7 cells were incubated with 500 ng/ml visfatin for 24 h. Afterwards, the cells were used for immunofluorescence staining to determine the role of visfatin on MMP-8 (green) expression (magnification 200×). *P<0.05 versus the control group; ** P<0.01 versus the control group. Data shown are the means ± SEM from three independent experiments that were performed in duplicate.