title: Mechanism of inhibition of matrix metalloproteinase-9 induction by NO in vascular smooth muscle cells.
abstract: Vascular smooth muscle (VSM) cell migration is a critical step in the development of a neointima after angioplasty. Matrix metalloproteinases (MMPs) degrade the basement membrane and extracellular matrix, facilitating VSM cell migration. Recently, we demonstrated that nitric oxide (NO) inhibits interleukin-1 beta (IL-1 beta)-stimulated MMP-9 induction in rat aortic VSM cells. In this study, we examined the hypothesis that NO inhibits MMP-9 induction by attenuating superoxide generation and extracellular signal-regulated kinase (ERK) activation. Stimulation of VSM cells with IL-1 beta significantly (P < 0.05) increased superoxide production, ERK activation, and MMP-9 induction. Pretreatment of VSM cells with the NO donor DETA NONOate significantly (P < 0.05) decreased IL-1 beta-stimulated superoxide generation. In addition, pretreatment of VSM cells with a specific ERK pathway inhibitor, PD-98059, or DETA NONOate inhibited IL-1 beta-stimulated ERK activation and MMP-9 induction. Direct exposure of VSM cells to increased superoxide levels by treatment with xanthine/xanthine oxidase increased ERK activation and MMP-9 induction, whereas pretreatment of cells with PD-98059 significantly (P < 0.05) inhibited xanthine/xanthine oxidase-stimulated ERK activation and MMP-9 induction. We conclude that NO inhibits IL-1 beta-stimulated MMP-9 induction by inhibiting superoxide generation and subsequent ERK activation.
authors.affiliation: Department of Anatomy and Cell Biology, The University of Iowa College of Medicine, Iowa City, Iowa 52242, USA.
authors.forename: M V
authors.initials: MV
authors.lastname: Gurjar
authors.forename: J
authors.initials: J
authors.lastname: DeLeon
authors.forename: R V
authors.initials: RV
authors.lastname: Sharma
authors.forename: R C
authors.initials: RC
authors.lastname: Bhalla
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects / Q000502:physiology; D007375:Interleukin-1 / Q000494:pharmacology; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D061965:Matrix Metalloproteinase Inhibitors; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009603:Nitroso Compounds / Q000494:pharmacology; D010766:Phosphorylation; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D007375:Interleukin-1; D061965:Matrix Metalloproteinase Inhibitors; D020030:Nitric Oxide Donors; D009603:Nitroso Compounds; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D013481:Superoxides; C094210:2,2'-(hydroxynitrosohydrazono)bis-ethanamine; D009569:Nitric Oxide; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D020780:Matrix Metalloproteinase 9; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one