title: Indole and its alkyl-substituted derivatives protect erythrocyte and DNA against radical-induced oxidation.
abstract: The antioxidant properties of 1,2,3,4-tetra-hydrocarbazole, 6-methoxy-1,2,3,4-tetrahydrocar-bazole (MTC), 2,3-dimethylindole, 5-methoxy-2,3-dimethylindole, and indole were investigated in the case of hemolysis of human erythrocytes and oxidative damage of DNA induced by 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH), respectively. The aim of this work was to explore the influence of methoxy, methyl, and cyclohexyl substituents on the antioxidant activities of indole derivatives. These indole derivatives were able to protect erythrocytes and DNA in a concentration-dependent manner. The alkyl-substituted indole can protect erythrocytes and DNA against AAPH-induced oxidation. Especially, the structural features of cyclohexyl and methoxy substituents made MTC the best antioxidant among the indole derivatives used herein. Finally, the interaction between these indole derivatives and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) radical cation and 2,2'-diphenyl-1-picrylhydrazyl, respectively, provided direct evidence for these indole derivatives to scavenge radicals and emphasized the importance of electron-donating groups for the free radical-scavenging activity of indole derivatives.
authors.affiliation: Department of Organic Chemistry, Jilin University, Changchun, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
authors.forename: Zai-Qun
authors.initials: ZQ
authors.lastname: Liu
mesh_terms: D000478:Alkylation / Q000187:drug effects; D000578:Amidines / Q000633:toxicity; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D019610:Cytoprotection / Q000187:drug effects*; D004247:DNA / Q000378:metabolism*; D004912:Erythrocytes / Q000187:drug effects*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology; D005609:Free Radicals / Q000633:toxicity*; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D007211:Indoles / Q000737:chemistry* / Q000494:pharmacology*; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D010851:Picrates; D013451:Sulfonic Acids; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D000578:Amidines; D052160:Benzothiazoles; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D005609:Free Radicals; D007211:Indoles; D010851:Picrates; D013451:Sulfonic Acids; D017392:Thiobarbituric Acid Reactive Substances; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; C046728:2,2'-azobis(2-amidinopropane); D004247:DNA; C004931:1,1-diphenyl-2-picrylhydrazyl