Blood pressure lowering effect of dietary-Epicatechin administration in L-NAME treated rats is associated with restoring Nitric Oxide levels

MARIA C. LITTERIO; GRAYSON JAGGERS; GULCIN SAGDICOGLU CELEPC; ANA M. ADAMO; MARIA A. COSTA; PATRICIA I. OTEIZA; CESAR G. FRAGA ; MONICA GALLEANO

FREE RADICAL BIOLOGY AND MEDICINE

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2012 vol. 53 p. 1894 - 1902

0891-5849

A b s t r a c t  Epidemiologicalandinterventionstudieshaveshownthattheintakeofcertainchocolatesorcocoa productsdecreasesbloodpressure(BP)inhumans.(_)-Epicatechinisthemostabundantflavanol present incocoaseedsanditsderivedfoods.Thisworkinvestigatestheeffectsofdietary(_)- epicatechinonBPinratsthatreceived No-nitro-L-argininemethylester(L-NAME)for4days.(_)- Epicatechinadministrationpreventedthe42mmHgincreaseinBPassociatedwiththeinhibitionofNO productioninadose-dependentmanner(0.2?4.0g/kgdiet).ThisBPeffectwasassociatedwitha reductioninL-NAME-mediatedincreaseintheindexesofoxidativestress(plasmaTBARSand GSSG/GSH2 ratio)andwitharestorationoftheNOconcentration.Atthevascularlevel,noneofthe treatmentsmodifiedeNOSexpression,but(_)-epicatechinadministrationavoidedtheL-NAME- mediateddecreaseineNOSactivityandincreaseinbothsuperoxideanionproductionandNOX subunitp47phox expression.Insummary,(_)-epicatechinwasabletopreventtheincreaseinBPandin oxidativestressandrestoredNObioavailability.Thefactthat(_)-epicatechinispresentinseveral plantsusuallyconsumedbyhumansgivesthepossibilityofdevelopingdietsrichinthoseplantsor pharmacologicalstrategiesusingthatflavonoidtodiminishBPinhypertensivesubjects.