title: Radical scavenging activities of Tyr-, Trp-, Cys- and Met-Gly and their protective effects against AAPH-induced oxidative damage in human erythrocytes.
abstract: Radical scavenging activities of Tyr-, Trp-, Cys- and Met-Gly and their protective effects against AAPH-induced oxidative damage in erythrocytes were evaluated in this study. This damage includes hemolysis, oxidation of hemoglobin, formation of MDA and the depletion of glutathione (GSH) and catalase (CAT). Results showed that Tyr- and Trp-Gly could quench the radicals effectively in ABTS and ORAC assays with TE (Trolox equivalent) values of more than 1.0 μmol TE/μmol, followed by Cys- and Met-Gly. All these dipeptides could protect erythrocytes against AAPH-induced hemolysis in a dose-dependent manner. They could also significantly (p<0.05) retard the oxidation of hemoglobin and depletion of GSH in erythrocytes. The protective effects of these dipeptides decreased in the following order: Trp-Gly>Tyr-Gly>Met-Gly>Cys-Gly, which were consistent with their peroxyl radical scavenging activities. It suggested that these dipeptides might protect erythrocytes against AAPH-induced oxidative damage, mainly by acting as the direct radical scavengers.
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 511458, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zheng
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 511458, China.
authors.forename: Hongzhu
authors.initials: H
authors.lastname: Dong
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 511458, China.
authors.forename: Guowan
authors.initials: G
authors.lastname: Su
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 511458, China.
authors.forename: Qiangzhong
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: College of Light Industry and Food Sciences, South China University of Technology, Guangzhou 510641, China; Guangdong Food Green Processing and Nutrition Regulation Technologies Research Center, Guangzhou 511458, China. Electronic address: femmzhao@scut.edu.cn.
authors.forename: Mouming
authors.initials: M
authors.lastname: Zhao
mesh_terms: D000578:Amidines / Q000633:toxicity*; D004151:Dipeptides / Q000494:pharmacology*; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016166:Free Radical Scavengers / Q000494:pharmacology*; D005978:Glutathione / Q000378:metabolism; D006454:Hemoglobins / Q000378:metabolism; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects
chemical_list: D000578:Amidines; D004151:Dipeptides; D016166:Free Radical Scavengers; D006454:Hemoglobins; C098230:methionylglycine; C028505:cysteinylglycine; C046728:2,2'-azobis(2-amidinopropane); C022013:glycyltyrosine; D005978:Glutathione; C016810:tryptophylglycine
keywords: ABTS radical scavenging activity; Antioxidant peptide; Erythrocytes hemolysis; ORAC value; Oxidative damage