title: Adiponectin inhibits pro-inflammatory signaling in human macrophages independent of interleukin-10.
abstract: Macrophages participate pivotally in the pathogenesis of many chronic inflammatory diseases including atherosclerosis. Adiponectin, a vasculoprotective molecule with insulin-sensitizing and anti-atherogenic properties, suppresses pro-inflammatory gene expression in macrophages by mechanisms that remain incompletely understood. This study investigated the effects of adiponectin on major pro-inflammatory signaling pathways in human macrophages. We demonstrate that pretreatment of these cells with adiponectin inhibits phosphorylation of nuclear factor kappaB inhibitor (IkappaB), c-Jun N-terminal kinase (JNK), and p38 mitogen-activated protein kinase (MAPK), induced by either lipopolysaccharide (LPS) or tumor necrosis factor (TNF) alpha, as well as STAT3 phosphorylation induced by interleukin-6 (IL6). Antagonism of IL10 by either neutralizing antibodies or siRNA-mediated silencing did not abrogate the anti-inflammatory actions of adiponectin, indicating that the ability of adiponectin to render human macrophages tolerant to various pro-inflammatory stimuli does not require this cytokine. A systematic search for adiponectin-inducible genes with established anti-inflammatory properties revealed that adiponectin augmented the expression of A20, suppressor of cytokine signaling (SOCS) 3, B-cell CLL/lymphoma (BCL) 3, TNF receptor-associated factor (TRAF) 1, and TNFAIP3-interacting protein (TNIP) 3. These results suggest that adiponectin triggers a multifaceted response in human macrophages by inducing the expression of various anti-inflammatory proteins that act at different levels in concert to suppress macrophage activation.
authors.affiliation: Division of Cardiovascular Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
authors.forename: Eduardo J
authors.initials: EJ
authors.lastname: Folco
authors.forename: Viviane Z
authors.initials: VZ
authors.lastname: Rocha
authors.forename: Marco
authors.initials: M
authors.lastname: López-Ilasaca
authors.forename: Peter
authors.initials: P
authors.lastname: Libby
mesh_terms: D052242:Adiponectin / Q000378:metabolism / Q000494:pharmacology; D000081242:B-Cell Lymphoma 3 Protein; D002460:Cell Line; D004268:DNA-Binding Proteins; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D020672:I-kappa B Proteins / Q000378:metabolism; D007249:Inflammation / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism / Q000494:pharmacology*; D015850:Interleukin-6 / Q000378:metabolism / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D020935:MAP Kinase Signaling System / Q000187:drug effects*; D008264:Macrophages / Q000378:metabolism*; D009687:Nuclear Proteins / Q000096:biosynthesis; D010766:Phosphorylation / Q000187:drug effects; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D050796:STAT3 Transcription Factor / Q000096:biosynthesis; D047990:TNF Receptor-Associated Factor 1 / Q000096:biosynthesis; D014157:Transcription Factors / Q000096:biosynthesis; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: C499918:ADIPOQ protein, human; D052242:Adiponectin; D000081242:B-Cell Lymphoma 3 Protein; C000631344:BCL3 protein, human; D004268:DNA-Binding Proteins; D020672:I-kappa B Proteins; C508609:IL10 protein, human; C508600:IL6 protein, human; D015850:Interleukin-6; D047908:Intracellular Signaling Peptides and Proteins; D008070:Lipopolysaccharides; D009687:Nuclear Proteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D047990:TNF Receptor-Associated Factor 1; C426747:TNIP3 protein, human; D014157:Transcription Factors; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D048031:JNK Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C076529:TNFAIP3 protein, human; D000072598:Tumor Necrosis Factor alpha-Induced Protein 3