Figure 4

Tissue inhibitor of metalloproteinase (TIMP)-2 suppressed the activity and expression of lipopolysaccharide (LPS)-induced matrix metalloproteinase (MMP)-3, -8 and -9. (A) BV2 cells transfected with TIMP-2 or control vector were treated with LPS (100 ng/ml) for 16 h, and the enzymatic activity of MMPs in cell culture supernatants were assessed using MMP activity assay kits. MMP activity units were expressed as a change in fluorescence intensity. Values are expressed as the means ± S.E.M. for three independent experiments. (B) Cells transfected with TIMP-2 or control vector were treated with LPS (100 ng/ml) for 6 h, and the mRNA expression of MMPs was monitored by RT-PCR. Representative gels are shown in the left panel, and quantification data are shown in the right panel (n = 3). *P < 0.05, significantly different from the LPS + control vector group. (C) Knockdown of TIMP-2 augmented MMP activities. *P < 0.05, significantly different from the LPS + control small interfering RNA (siRNA) group.