Acacetin inhibits expression of matrix metalloproteinases via a MAPK-dependent mechanism in fibroblast-like synoviocytes

It is well known that rheumatoid arthritis (RA) is an autoimmune joint disease in which fibroblast-like synoviocytes (FLSs) play a pivotal role. In this study, we investigated the anti-arthritic properties of acacetin in FLSs. The expression of matrix metalloproteinase (MMP)-1, MMP-3 and MMP-13 were investigated by quantitative RT-PCR and western blot at gene and protein levels. At the same time, the phosphorylation of mitogen-activated protein kinases (MAPK) was investigated. The DNA-binding activity of NF-κB was investigated by electrophoretic mobility shift assay. We found that acacetin inhibits p38 and JNK phosphorylation and reduces MMP-1, MMP-3 and MMP-13 expression in interleukin-1β-induced FLSs. Our results suggest that acacetin has antiarthritic effects in FLSs. Thus, acacetin should be further studied for the treatment of arthritis.