title: [Paraoxonase: its multiple functions and pharmacological regulation].
abstract: Homocysteine, a non-protein amino acid,  important risk factor for atherosclerosis and thrombosis, causes dysfunction of vascular endothelial cells traduced in inadequate vasodilatation mechanism, is pro-inflammatory and induces endoplasmic reticulum stress. The more reactive conformation is the homocysteine thiolactone (HcyT), product to the nonspecific action of methionyl-tRNA synthetase, which is incorporated into proteins by disulfide bonds (S-homocysteinilation) or amide bonds (N-homocysteinilation) affecting protein structure and function leading to cell toxicity, autoimmune responses and atherogenesis. The enzyme paraoxonase-1 (PON1), part of high density lipoprotein (HDL), had been studied only for its ability to hydrolyze organophosphate derivatives. But, more recently it has been attributed other important role. The enzyme activities are involving in protecting against the development of atherosclerosis, by preventing oxidation of  lipoproteins and hydrolyze HcyT. There is growing evidence about the protective role of PON1 in vascular disease. Genetic factors (polymorphisms of the PON1), environmental and lifestyle influence their concentration and biological activity, but drugs used as cardioprotectives and lipid-lowering or others, such as antibiotics and steroids, are also important modulators. This review is an updated of the most prominent information on clinical and  experimental studies for understanding the role of the PON-1 in the protection against development of atherosclerosis.
authors.affiliation: Centro de Altos Estudios en Ciencias Humanas y de la Salud. Universidad Abierta Interamericana. Área de Investigación. Instituto de Oncología Ángel H. Roffo. Universidad de Buenos Aires. Consejo Nacional de Investigaciones Científicas y Técnicas. Argentina.
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Fridman
authors.forename: Alicia Graciela
authors.initials: AG
authors.lastname: Fuchs
authors.forename: Rafael
authors.initials: R
authors.lastname: Porcile
authors.forename: Analía Verónica
authors.initials: AV
authors.lastname: Morales
authors.forename: Luis Osvaldo
authors.initials: LO
authors.lastname: Gariglio
mesh_terms: D043303:Aryldialkylphosphatase / Q000187:drug effects* / Q000502:physiology*; D050197:Atherosclerosis / Q000209:etiology*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D043303:Aryldialkylphosphatase