Objective        To study the effects of interlukin-1β (IL-1β) on the activity of matrix metalloproteinase-2 (MMP-2) in synovial cells from human knee joint

and the effects of MAPK or NF-κB signal pathway inhibitors on IL-1β-induced MMP-2 activity.       Methods      In vitro cultured synovial cells were treated with IL-1β at different concentrations

and gelatin zymography was performed to detect MMP-2 activity at 72 h. IL-1β  of 10 ng/ml alone or in combination with each of four signal pathway inhibitors (NF-κB inhibitor: Bay11-7082; MAPK inhibitor: SB203580

PD98059 and SP600125) were used to treat the synovial cells

and MMP-2 activity was detected at 12

24

48 and 72 h

respectively.        Results        IL-1β significantly increased MMP-2 activity in synovial cells with increased concentration or time (P0.05). Bay11-7082 dramatically inhibited IL-1β-stimulated MMP-2 activity

and the activity was decreased to 13% compared with the IL-1β group (P0.01). However

other inhibitors had no significant effect on the IL-1β-stimulated MMP-2 activity(P0.05).        Conclusion        IL-1β significantly increases MMP-2 activity through NF-κB signal pathway in synovial cells in a dose- and time-dependent manner.