In vitro inhibition of linoleic acid peroxidation by primary S-nitrosothiols

Autor(es)

Simplicio, Fernanda I. ^[1] ; Seabra, Amedea B. ^[1] ; de Souza, Gabriela F. P. ^[1] ; de Oliveira, Marcelo G. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Quim, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 21, n. 10, p. 1885-1895, 2010.
• Citações Web of Science: 7

Resumo

Nitric oxide (•NO) is an effective chain-breaking antioxidant in the inhibition of lipid peroxidation and circulates in vivo mainly as primary S-nitrosothiols (RSNOs). In this work, the in vitro peroxidation of linoleic acid-SDS comicelles (LA-SDS) catalyzed by soybean lipoxygenase (SLO) and FeII ions was monitored in the presence and absence of three primary RSNOs: S-nitrosocysteine, S-nitroso-N-acetylcysteyne and S-nitrosoglutathione. Kinetic measurements based on the formation of conjugated double bonds and fluorescent oxidized LA-lysine adducts, showed that RSNOs are more potent antioxidants than their corresponding free thiols (RSHs) in equimolar conditions. These results are consistent with the blocking of LA-SDS peroxidation by RSNOs through the inactivation of peroxyl/alkoxyl (LOO•/LO•) radicals, leading to nitrogen-containing products of oxidized LA, which release free •NO. These results indicate that endogenous RSNOs may play a major role in the blocking of lipid peroxidation in vivo, through the primary inactivation of alkoxyl/peroxyl radicals and also of preformed lipid hydroperoxides. (AU)

• Processo FAPESP: 07/55877-3 - Doadores de óxido nítrico para o tratamento da síndrome metabólica: mecanismos de ação e desenvolvimento de formulações
• Beneficiário: Gabriela Freitas Pereira de Souza
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto