Decursin Inhibits Induction of Inflammatory Mediators by Blocking Nuclear Factor-κB Activation in Macrophages

Abstract

In the course of screening inhibitors of matrix metalloproteinase (MMP)-9 induction in macrophages, we isolated decursin, a coumarin compound, from the roots of Angelicae gigas. As a marker for the screening and isolation, we tested expression of MMP-9 in RAW264.7 cells and THP-1 cells after treatment with bacterial lipopolysaccharide (LPS), the TLR-4 ligand. Decursin suppressed MMP-9 expression in cells stimulated by LPS in a dose-dependent manner at concentrations below 60 M with no sign of cytotoxicity. The suppressive effect of decursin was observed not only in cells stimulated with ligands for TLR4, TLR2, TLR3, and TLR9 but also in cells stimulated with interleukin (IL)-1␤, and tumor necrosis factor (TNF)-␣, indicating that the molecular target of decursin is common signaling molecules induced by these stimulants. In addition to the suppression of MMP-9 expression, decursin blocked nitric oxide production and cytokine (IL-8, MCP-1, IL-1␤, and TNF-␣) secretion induced by LPS. To find out the molecular mechanism responsible for the suppressive effect of decursin, we analyzed signaling molecules involved in the TLR-mediated activation of MMP-9 and cytokines. Decursin blocked phosphorylation of IB and nuclear translocation of NF-B in THP-1 cells activated with LPS. Furthermore, expression of a luciferase reporter gene under the promoter containing NF-B binding sites was blocked by decursin. These data indicate that decursin is a novel inhibitor of NF-B activation in signaling induced by TLR ligands and cytokines.

Differential regulation of matrix metalloproteinase 2 and matrix metalloproteinase 9 by activated protein C: Relevance to inflammation in rheumatoid arthritis

“…These sites make MMP-9 susceptible to induction by proinflammatory cytokines, particularly TNF␣, a key mediator in the pathogenesis and maintenance of rheumatoid synovitis. Previous studies have supported the role of NF-B in the TNF␣-stimulated production of MMP-9 in a number of cell types, including normal human fibroblasts (46), human macrophages (47), and rat chondrocytes (48). The current study demonstrates that APC inhibits TNF␣ production and NF-B activation in unstimulated and/or stimulated monocytes.…”

Modulation of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in RAW264.7 cells by irradiation

“…it is believed that the production of MMP-9 is associated with a number of factors, such as the transcription factors aP-1 and nuclear factor-κB (NF-κB) (23,24), reactive oxygen species (roS) (19), il-1β (19) and TnF-α (25). For macrophages, ionizing radiation activates transcription genes, such as nF-κB (26,27), and induces the production of RoS (28), TnF-α and il-1 (10-12).…”

CD300F Blocks Both MyD88 and TRIF-Mediated TLR Signaling through Activation of Src Homology Region 2 Domain-Containing Phosphatase 1

“…For the construction of a CD300F-expressing construct, the CD300F full length or its cytoplasmic tail deletion mutant was PCR amplified and cloned into a pGEM-T Easy vector, which was further digested with EcoRI to clone into a corresponding site in pCI-neo mammalian expression vector. Expression constructs for CD4-TLR4, the death domain of MyD88, wildtype TRIF, and TRAF6, the luciferase reporter gene under the control of NFkB binding sites, and the Renilla-luciferase construct for transfection control were described previously (19)(20)(21)(22).…”