Nuclear factor kappaB activity is essential for matrix metalloproteinase-1 and -3 upregulation in rabbit dermal fibroblasts.

Expression of matrix metalloproteinases (MMPs)-1 and -3 in fibroblasts is upregulated by pro-inflammatory cytokines and growth factors during proliferative inflammatory processes, including wound healing and rheumatoid arthritis. The Activator Protein-1 (AP-1) transcription factor is essential but, we show here, not sufficient for upregulation because platelet derived growth factor (PDGF) and basic fibroblast growth factor (bFGF), which strongly activate AP-1, poorly induce MMP-1 and -3. Interleukin-1alpha, which activates nuclear factor-kappaB (NF-kappaB), synergistically upregulates MMP-1 and -3 expression in the presence of bFGF or PDGF. Adenovirus mediated overexpression of IkappaBalpha, the inhibitor of NF-kappaB, completely suppresses MMP-1 and -3 protein and mRNA expression. Hence, we show for the first time that (NF-kappaB) activity is also essential for MMP-1 and -3 upregulation. Copyright 1999 Academic Press.