title: Nitric oxide modulates lipopolysaccharide-induced endothelial platelet endothelial cell adhesion molecule expression via interleukin-10.
abstract: We have shown previously that nitric oxide (NO) controls platelet endothelial cell adhesion molecule (PECAM-1) expression on both neutrophils and endothelial cells under physiological conditions. Here, the molecular mechanism by which NO regulates lipopolysaccharide (LPS)-induced endothelial PECAM-1 expression and the role of interleukin (IL)-10 on this control was investigated. For this purpose, N-(G)-nitro-L-arginine methyl ester (L-NAME; 20 mg/kg/day for 14 days dissolved in drinking water) was used to inhibit both constitutive (cNOS) and inducible nitric oxide (iNOS) synthase activities in LPS-stimulated Wistar rats (5 mg/kg, intraperitoneally). This treatment resulted in reduced levels of serum NO. Under this condition, circulating levels of IL-10 was enhanced, secreted mainly by circulating lymphocytes, dependent on transcriptional activation, and endothelial PECAM-1 expression was reduced independently on reduced gene synthesis. The connection between NO, IL-10 and PECAM-1 expression was examined by incubating LPS-stimulated (1 µg/ml) cultured endothelial cells obtained from naive rats with supernatant of LPS-stimulated lymphocytes, which were obtained from blood of control or L-NAME-treated rats. Supernatant of LPS-stimulated lymphocytes obtained from L-NAME-treated rats, which contained higher levels of IL-10, reduced LPS-induced PECAM-1 expression by endothelial cells, and this reduction was reversed by adding the anti-IL-10 monoclonal antibody. Therefore, an association between NO, IL-10 and PECAM-1 was found and may represent a novel mechanism by which NO controls endothelial cell functions.
authors.affiliation: Department of Clinical and Toxicological Analyses, School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: C B
authors.initials: CB
authors.lastname: Hebeda
authors.forename: S A
authors.initials: SA
authors.lastname: Teixeira
authors.forename: E K
authors.initials: EK
authors.lastname: Tamura
authors.forename: M N
authors.initials: MN
authors.lastname: Muscará
authors.forename: S B V
authors.initials: SB
authors.lastname: de Mello
authors.forename: R P
authors.initials: RP
authors.lastname: Markus
authors.forename: S H P
authors.initials: SH
authors.lastname: Farsky
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D007249:Inflammation / Q000276:immunology / Q000378:metabolism*; D016753:Interleukin-10 / Q000097:blood / Q000276:immunology / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000276:immunology*; D008214:Lymphocytes / Q000378:metabolism*; D019331:NG-Nitroarginine Methyl Ester / Q000008:administration & dosage / Q000494:pharmacology; D009569:Nitric Oxide / Q000097:blood / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000037:antagonists & inhibitors / Q000378:metabolism; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000235:genetics* / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000911:Antibodies, Monoclonal; D004791:Enzyme Inhibitors; D008070:Lipopolysaccharides; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D016753:Interleukin-10; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D019331:NG-Nitroarginine Methyl Ester