Effect of taurine chloramine on the production of matrix metalloproteinases (MMPs) in adiponectin- or IL-1β-stimulated fibroblast-like synoviocytes

BACKGROUND: Adiponectin greatly stimulated the expression of matrix metalloproteinases (MMPs) in fibroblast-like synoviocytes (FLSs) as did IL-1β. We wondered whether taurine chloramine (TauCl) inhibits the production of MMPs stimulated by adiponectin in the same pattern as by IL-1β stimulation in vitro METHODS: Synovial cells from rheumatoid arthritis (RA) patients were treated with adiponectin or interleukin (IL)-1β for 24 hr in the presence or absence of TauCl. The culture supernatant was collected and the levels of MMPs were measured by enzyme-linked immunosorbent assay (ELISA). The IκB signaling pathways stimulated by adiponectin were studied and the levels of NF-κB in the nuclei of the cells were analyzed by ELISA. RESULTS: TauCl (600 µM) inhibited MMP-13, but not MMP-1, expression in IL-1β-stimulated RA FLSs. However, TauCl at the same concentration significantly inhibited the production of both adiponectin-stimulated MMP-1 and MMP-13 expression. TauCl inhibited the degradation of IκB-α stimulated by adiponectin, but not by IL-1β. Similarly, the level of NF-κB in the nucleus was increased by adiponectin stimulation and was inhibited by 600 µM TauCl. However, the levels of NF-κB increased by IL-1β stimulation were not inhibited by 600 µM TauCl. CONCLUSIONS: TauCl more effectively inhibited MMPs expression induced by adiponectin than that by IL-1β in RA FLS, suggesting that TauCl plays an important role in down-regulating the expression of MMPs in arthritic joints.