Tumor necrosis factor-α stimulates the expression of C-C chemokine ligand 2 gene in fibroblasts from the human nasal polyp through the pathways of mitogen-activated protein kinase
Journal
American Journal of Rhinology
Journal Volume
21
Journal Issue
2
Pages
251-255
Date Issued
2007
Author(s)
Abstract
Background: Recruitment of macrophages is crucial to the pathogenesis of the nasal polyp (NP) because this disease is believed to be inflammation related. Information regarding the expression of C-C chemokine ligand 2 (CCL2), an essential modulator of monocyte chemotaxis in nasal polyp fibroblasts (NPFs), remains unavailable. In this study, the effects of tumor necrosis factor (TNF)-α on CCL2 expression in NPFs and the signaling pathway involved were investigated. Methods: Primary cultures of NPFs were established from NPs. The expressions of CCL2, c-Fos, and c-Jun mRNAs in NPF after TNF-α stimulation were detected by Northern blot. Western blot was used to examine the activation of mitogen-activated protein kinase (MAPK) signaling pathways. Activator protein (AP) 1/DNA interactions were evaluated by electrophoretic mobility shift assay (EMSA). Results: Northern blot showed that TNF-α stimulated CCL2 gene expression in NPFs. Significant increase of B-Raf, phosphorated MAPK including mitogen-activated ERK-activate kinase (MEK)1/2, extracellular signal-related kinase 1/2, and p38 were detected by Western blot. c-Fos and c-Jun mRNAs were induced by TNF-α, and PD98059 (MEK inhibitor) and SB203580 (p38 inhibitor) abolished the up-regulation of c-Fos. EMSA revealed that TNF-α increased AP-1/DNA binding, and PD98059 and SB203580 attenuated this reaction, possibly via reducing c-Fos synthesis. PD98059 and curcumin (AP-1 inhibitor) markedly suppressed the TNF-α-induced CCL2 expression, whereas the effect of SB203580 was less noted. Conclusion: TNF-α induces CCL2 transcription in NPFs. B-Raf/MEK/ERK signaling cascade and to a less extent the p38 pathway are responsible for c-Fos activation and the subsequent AP-1/DNA interaction leading to CCL2 expression. Copyright ? 2007, OceanSide Publications, Inc.
SDGs
Other Subjects
2 (2 amino 3 methoxyphenyl)chromone; 4 (4 fluorophenyl) 2 (4 methylsulfinylphenyl) 5 (4 pyridyl)imidazole; B Raf kinase; curcumin; messenger RNA; mitogen activated protein kinase 1; mitogen activated protein kinase 3; mitogen activated protein kinase p38; monocyte chemotactic protein 1; protein c fos; protein c jun; transcription factor AP 1; tumor necrosis factor alpha; article; cell culture; cell stimulation; controlled study; enzyme activation; enzyme phosphorylation; fibroblast; gel mobility shift assay; human; human cell; human tissue; Northern blotting; nose polyp; protein DNA binding; protein DNA interaction; protein expression; protein synthesis; signal transduction; upregulation; Western blotting; Blotting, Northern; Blotting, Western; Cells, Cultured; Chemokine CCL2; Fibroblasts; Gene Expression; Genes, fos; Genes, jun; Humans; MAP Kinase Kinase Kinase 1; MAP Kinase Kinase Kinase 2; MAP Kinase Signaling System; Mitogen-Activated Protein Kinase 1; Mitogen-Activated Protein Kinase 3; Mitogen-Activated Protein Kinases; Nasal Polyps; p38 Mitogen-Activated Protein Kinases; Proto-Oncogene Proteins B-raf; Signal Transduction; Transcription Factor AP-1; Tumor Necrosis Factor-alpha
Type
journal article