Epigallocatechin-3-gallate suppresses TNF-alpha -induced production of MMP-1 and -3 in rheumatoid arthritis synovial fibroblasts.

Rheumatoid arthritis (RA) synovial fibroblasts produce matrix metaloproteinases (MMPs), which destroy cartilage and bone in RA joint. Tumor necrosis factor-alpha (TNF-alpha) is one of the most important mediator leading to MMP production in RA synovial fibroblasts. Here we show that epigallocatechin-3-Gallate (EGCG) suppresses TNF-alpha-induced production of MMP-1 and MMP-3 in RA synovial fibroblasts, which was accompanied by inhibition of mitogen activated protein kinase (MAPK) and activator protein-1 (AP-1) pathways. EGCG treatment resulted in dose-dependent inhibition of TNF-alpha-induced production of MMP-1 and MMP-3 at the protein and mRNA levels in RA synovial fibroblast. EGCG treatment also inhibited TNF-alpha-induced phosphorylation of MAPKs, such as ERK1/2, p38, JNK. Electrophoretic mobility shift assay revealed that EGCG inhibits binding of AP-1 proteins to its response elements in synovial fibroblast treated. Thus, EGCG may play a role in regulating inflammation and bone destruction in RA patients.