title: Oncostatin M and TLR-4 ligand synergize to induce MCP-1, IL-6, and VEGF in human aortic adventitial fibroblasts and smooth muscle cells.
abstract: Accumulating evidence suggests that adventitial fibroblasts play a significant role in contributing to inflammation of the arterial wall and pathogenesis of atherosclerosis. The effects of gp130 cytokines on these cells (including oncostatin M-[OSM] and IL-6), some of which have been implicated in atherosclerosis, are currently unknown. Experiments were performed to determine whether gp130 cytokines regulate human aortic adventitial fibroblasts (HAoAFs) or smooth muscle cells (HAoSMCs) alone or in context of TLR-4 ligands (also implicated in atherosclerosis). HAoAFs and HAoSMCs were stimulated with LPS and/or one of OSM, IL-6, IL-11, IL-31, or LIF. ELISAs performed on cell supernatants showed that stimulation with OSM alone caused increased MCP-1, IL-6, and VEGF levels. When combined, LPS and OSM synergized to increase MCP-1, IL-6, VEGF protein, and mRNA expression as assessed by qRT-PCR, in both HAoAFs and HAoSMCs, while LPS-induced IL-8 levels were reduced. Such effects were not observed with other gp130 cytokines. Signalling pathways including STATs, MAPKinases, and NF κ B were activated, and LPS induced steady state mRNA levels of the OSM receptor chains OSMR β and gp130. The results suggest that OSM is able to synergize with TLR-4 ligands to induce proinflammatory responses by HAoAFs and HAoSMCs, supporting the notion that OSM regulation of these cells contributes to the pathogenesis of atherosclerosis.
authors.affiliation: McMaster Immunology Research Centre, Department of Pathology and Molecular Medicine, McMaster University, ON, Canada L8S 4K1.
authors.forename: David
authors.initials: D
authors.lastname: Schnittker
authors.forename: Karen
authors.initials: K
authors.lastname: Kwofie
authors.forename: Ali
authors.initials: A
authors.lastname: Ashkar
authors.forename: Bernardo
authors.initials: B
authors.lastname: Trigatti
authors.forename: Carl D
authors.initials: CD
authors.lastname: Richards
mesh_terms: D063194:Adventitia / Q000166:cytology; D001011:Aorta / Q000166:cytology / Q000378:metabolism / Q000473:pathology; D050197:Atherosclerosis / Q000503:physiopathology; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D017370:Interleukin-11 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism*; D016209:Interleukin-8 / Q000378:metabolism; D008024:Ligands; D008070:Lipopolysaccharides / Q000494:pharmacology; D032389:Myocytes, Smooth Muscle / Q000166:cytology* / Q000378:metabolism; D053683:Oncostatin M / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: C111835:CCL2 protein, human; D018932:Chemokine CCL2; C508600:IL6 protein, human; D017370:Interleukin-11; D015850:Interleukin-6; D016209:Interleukin-8; D008024:Ligands; D008070:Lipopolysaccharides; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D053683:Oncostatin M