title: Interleukin 10 antioxidant effect decreases leukocytes/endothelial interaction induced by tumor necrosis factor α.
abstract: Little is known about the endothelial mechanisms involved in the anti-inflammatory effects of interleukin 10 (IL-10). The goal of this study was to evaluate the effects of IL-10 on endothelial oxidative stress and endothelial inflammation induced by tumor necrosis factor α (TNF-α). Production of reactive oxygen species (ROS) in perfused human umbilical vein endothelial cells (HUVECs) was studied by fluorescent microscopy using dichlorodihydrofluorescein diacetate. Tumor necrosis factor α (1 ng/mL) was added to the perfusion medium in the absence and presence of IL-10 (1 ng/mL). The role of phosphatidylinositol 3-kinase (PI3-kinase) was assessed using wortmannin and LY 2940002 (inhibitors of PI3-kinase). Specific inhibition of p110 α and p110 γ/δ PI3-kinase subunits was studied using A66 and TG100-115. As well, levels of ceramide and intercellular adhesion molecule 1 (ICAM-1) expression were measured. Finally, the effect of IL-10 on TNF-α-induced leukocyte/endothelium interaction was examined using an ex vivo perfused vessel model. Interleukin 10 significantly reduced dichlorodihydrofluorescein diacetate fluorescence induced by TNF-α in HUVECs (12.5% ± 3.2% vs. 111.7% ± 21.6% at 60 min). Pretreatment by LY2940002 or wortmannin restored ROS production induced by TNF-α in the presence of IL-10. In HUVECs treated by TNF-α + IL-10, inhibition of p110 α PI3-kinase subunit significantly increased ROS production, whereas p110 γ/δ inhibition did not have a significant effect. Pretreatment with IL-10 significantly decreased TNF-α-induced increased levels of ceramide (TNF-α vs. TNF-α + IL-10: 6,278 ± 1,013 vs. 1,440 ± 130 pmol/mg prot), as well as ICAM-1 expression and leukocyte adhesion (TNF-α vs. TNF-α + IL-10: 26.8 ± 2.6 vs. 6.7 ± 0.4 adherent leukocytes/field at 15 min). Interleukin 10 decreases the level of inflammation induced by TNF-α in endothelial cells by reducing the TNF-α-induced ROS production, ICAM-1 expression, and leukocyte adhesion to the endothelium. The antioxidant effect of IL-10 is mediated through PI3-kinase and is paralleled by a decrease in ceramide synthesis induced by TNF-α.
authors.affiliation: Assistance Publique des Hôpitaux de Paris (AP-HP), Service d'Anesthésie-Réanimation, Hôpitaux Universitaires Paris-Sud, Centre Hospitalier Universitaire de Bicêtre, Université Paris XI, Paris, France. olivier.huet@bakeridi.edu.au
authors.forename: Olivier
authors.initials: O
authors.lastname: Huet
authors.forename: Elisabette
authors.initials: E
authors.lastname: Laemmel
authors.forename: Yi
authors.initials: Y
authors.lastname: Fu
authors.forename: Laurent
authors.initials: L
authors.lastname: Dupic
authors.forename: Andrea
authors.initials: A
authors.lastname: Aprico
authors.forename: Karen L
authors.initials: KL
authors.lastname: Andrews
authors.forename: Shirley L
authors.initials: SL
authors.lastname: Moore
authors.forename: Anatole
authors.initials: A
authors.lastname: Harrois
authors.forename: Peter L
authors.initials: PL
authors.lastname: Meikle
authors.forename: Eric
authors.initials: E
authors.lastname: Vicaut
authors.forename: Jaye P F
authors.initials: JP
authors.lastname: Chin-Dusting
authors.forename: Jacques
authors.initials: J
authors.lastname: Duranteau
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002448:Cell Adhesion / Q000187:drug effects; D002478:Cells, Cultured; D002518:Ceramides / Q000378:metabolism; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis / Q000235:genetics; D016753:Interleukin-10 / Q000494:pharmacology*; D007962:Leukocytes / Q000187:drug effects* / Q000502:physiology; D018384:Oxidative Stress / Q000187:drug effects; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors* / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D002518:Ceramides; D017382:Reactive Oxygen Species; D014409:Tumor Necrosis Factor-alpha; D018799:Intercellular Adhesion Molecule-1; D016753:Interleukin-10; D019869:Phosphatidylinositol 3-Kinases