title: Simvastatin prevents load-induced protein tyrosine nitration in overloaded hearts.
abstract: Hydroxymethylglutaryl-coenzyme A reductase inhibitors prevent load-induced left ventricular hypertrophy (LVH). Whether this effect is related to antioxidant properties of this class of drugs is poorly understood. The aim of the present report was to evaluate the regulation of nitrotyrosine production during the development of load-induced LVH and the effect of simvastatin treatment in this process. Rats were subjected to aortic constriction up to 15 days. LVH was evaluated by left/right ventricle mass ratio. Myocardial content of nitrotyrosine, nitric oxide synthase (NOS) isoforms, and phagocyte-type NAD(P)H-oxidase subunits (p67-phox and p22-phox) were analyzed by immunoblotting and immunohistochemistry assays. Another group of rats received treatment with either simvastatin or placebo for 15 days after the onset of pressure overload, and their hearts were also studied. Myocardial nitrotyrosine content was increased from 3 to 15 days of pressure overload in regions of cardiac myocytes in close apposition to myocardial stroma during LVH. Neuronal NOS (nNOS), inducible NOS (iNOS), and endothelial NOS (eNOS) isoforms had their expression increased in coronary vessels (nNOS and iNOS) and in myocardial stroma (eNOS) from day 3 to day 7 of aortic constriction. However, p67-phox and p22-phox expression was increased in cells of myocardial stroma in parallel to augmented myocardial nitrotyrosine content. Simvastatin treatment inhibited the increases in myocardial nitrotyrosine content and in p67-phox and p22-phox expression, and significantly reduced LVH. In conclusion, antioxidant properties of simvastatin might play a role in myocardial remodeling induced by pressure overload.
authors.affiliation: Department of Internal Medicine, School of Medicine, State University of Campinas, Brazil.
authors.forename: Wilson
authors.initials: W
authors.lastname: Nadruz
authors.forename: Valquer Jose
authors.initials: VJ
authors.lastname: Lagosta
authors.forename: Heitor
authors.initials: H
authors.lastname: Moreno
authors.forename: Otavio Rizzi
authors.initials: OR
authors.lastname: Coelho
authors.forename: Kleber Gomes
authors.initials: KG
authors.lastname: Franchini
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001011:Aorta; D003250:Constriction; D003331:Coronary Vessels / Q000201:enzymology; D004790:Enzyme Induction; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D017379:Hypertrophy, Left Ventricular / Q000188:drug therapy / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D026901:Membrane Transport Proteins / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009252:NADPH Dehydrogenase / Q000378:metabolism; D019255:NADPH Oxidases; D019001:Nitric Oxide Synthase / Q000378:metabolism; D018384:Oxidative Stress; D010750:Phosphoproteins / Q000378:metabolism; D011312:Pressure; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D019821:Simvastatin / Q000494:pharmacology* / Q000627:therapeutic use; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000096:biosynthesis*; D020257:Ventricular Remodeling / Q000502:physiology
chemical_list: D000975:Antioxidants; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D007527:Isoenzymes; D026901:Membrane Transport Proteins; D010750:Phosphoproteins; D011506:Proteins; C079789:neutrophil cytosol factor 67K; C002744:3-nitrotyrosine; D014443:Tyrosine; D019821:Simvastatin; D019001:Nitric Oxide Synthase; D019255:NADPH Oxidases; C086986:CYBA protein, human; D009252:NADPH Dehydrogenase; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases