Nitric Oxide Regulates Vascular Cell Adhesion Molecule 1 Gene Expression and Redox-Sensitive Transcriptional Events in Human Vascular Endothelial Cells

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 93; no. 17; pp. 9114 - 9119
• Main Authors: Khan, Bobby V., Harrison, David G., Olbrych, Matthew T., Alexander, R. Wayne, Medford, Russell M.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences of the United States of America 20-08-1996; National Acad Sciences; National Academy of Sciences
• Subjects: Antioxidants - pharmacology; Base Sequence; Cell adhesion molecules; Cell Membrane - metabolism; Cytokines; Cytokines - pharmacology; Diethylamines - pharmacology; Drug Interactions; E-Selectin - biosynthesis; Endothelial cells; Endothelium, Vascular - drug effects; Gels; Gene expression; Gene Expression Regulation; Human umbilical vein endothelial cells; Humans; Intercellular Adhesion Molecule-1 - biosynthesis; Lipid Peroxidation; Lipids; Messenger RNA; Molecular Sequence Data; NF-kappa B - metabolism; Nitric oxide; Nitric Oxide - pharmacology; Oxidation-Reduction; Reactive oxygen species; Transcription, Genetic; Unsaturated fatty acids; Vascular Cell Adhesion Molecule-1 - biosynthesis
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.93.17.9114

Decreased nitric oxide (NO) activity, the formation of reactive oxygen species, and increased endothelial expression of the redox-sensitive vascular cell adhesion molecule 1 (VCAM-1) gene in the vessel wall are early and characteristic features of atherosclerosis. To explore whether these phenomena are functionally interrelated, we tested the hypothesis that redox-sensitive VCAM-1 gene expression is regulated by a NO-sensitive mechanism. In early passaged human umbilical vein endothelial cells and human dermal microvascular endothelial cells, the NO donor diethyl-amine-NO (DETA-NO, 100 μ M) reduced VCAM-1 gene expression induced by the cytokine tumor necrosis factor α (TNF-α , 100 units/ml) at the cell surface level by 65% and intracellular adhesion molecule 1 (ICAM-1) gene expression by 35%. E-selectin gene expression was not affected. No effect on expression of cell adhesion molecules was observed with DETA alone. Moreover, DETA-NO suppressed TNF-α -induced mRNA accumulation of VCAM-1 and TNF-α -mediated transcriptional activation of the human VCAM-1 promoter. Conversely, treatment with NG-monomethyl-L-arginine (L-NMMA, 1 mM), an inhibitor of NO synthesis, augmented cytokine induction of VCAM-1 and ICAM-1 mRNA accumulation. By gel mobility shift analysis, DETA-NO inhibited TNF-α activation of DNA binding protein activity to the VCAM-1 NF-κ B like binding sites. Peroxy-fatty acids such as 13-hydroperoxydodecanoeic acid (linoleyl hydroperoxide) may serve as an intracellular signal for NF-κ B activation. Using thin layer chromatography, DETA-NO (100 μ M) suppressed formation of this metabolite, suggesting that DETA-NO modifies the reactivity of oxygen intermediates in the vascular endothelium. Through this mechanism, NO may function as an immunomodulator of the vessel wall and thus mediate inflammatory events involved in the pathogenesis of atherosclerosis.