title: L-carnitine attenuates oxidative stress in hypertensive rats.
abstract: The present study aimed to investigate whether l-carnitine (LC) protects the vascular endothelium and tissues against oxidative damage in hypertension. Antioxidant enzyme activities, glutathione and lipid peroxidation were measured in the liver and heart of spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Nitrite and nitrate levels and total antioxidant status (TAS) were evaluated in plasma, and the expression of endothelial nitric oxide synthase (eNOS) and p22phox subunit of NAD(P)H oxidase was determined in aorta. Glutathione peroxidase activity was lower in SHR than in WKY rats, and LC increased this activity in SHR up to values close to those observed in normotensive animals. Glutathione reductase and catalase activities, which were higher in SHR, tended to increase after LC treatment. No differences were found in the activity of superoxide dismutase among any animal group. The ratio between reduced and oxidized glutathione and the levels of lipid peroxidation were respectively decreased and increased in hypertensive rats, and both parameters were normalized after the treatment. Similarly, LC was able to reverse the reduced plasma nitrite and nitrate levels and TAS observed in SHR. We found no alterations in the expression of aortic eNOS among any group; however, p22phox mRNA levels showed an increase in SHR that was reversed by LC. In conclusion, chronic administration of LC leads to an increase in hepatic and cardiac antioxidant defense and a reduction in the systemic oxidative process in SHR. Therefore, LC might increase NO availability in SHR aorta by a reduction in superoxide anion production.
authors.affiliation: Department of Physiology and Zoology, Faculty of Pharmacy, University of Seville, E-41012 Seville, Spain.
authors.forename: Lucía
authors.initials: L
authors.lastname: Gómez-Amores
authors.forename: Alfonso
authors.initials: A
authors.lastname: Mate
authors.forename: José L
authors.initials: JL
authors.lastname: Miguel-Carrasco
authors.forename: Luís
authors.initials: L
authors.lastname: Jiménez
authors.forename: Angeles
authors.initials: A
authors.lastname: Jos
authors.forename: Ana M
authors.initials: AM
authors.lastname: Cameán
authors.forename: Elisa
authors.initials: E
authors.lastname: Revilla
authors.forename: Consuelo
authors.initials: C
authors.lastname: Santa-María
authors.forename: Carmen M
authors.initials: CM
authors.lastname: Vázquez
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002331:Carnitine / Q000494:pharmacology*; D005978:Glutathione / Q000097:blood; D019803:Glutathione Disulfide / Q000097:blood; D005980:Glutathione Reductase / Q000378:metabolism; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005978:Glutathione; D002331:Carnitine; D019803:Glutathione Disulfide