title: In vitro and in vivo assessment of the antioxidant activity of melatonin and related indole derivatives.
abstract: Effects of melatonin and some structurally related indole compounds were studied by in vitro methods such as (i) an inhibition of the hyaluronic acid degradation and (ii) a standard lipid peroxidation assay. In vivo approach was based on the alloxan model of hyperglycaemia. Reduction of the viscosity of a hyaluronic acid solution in the reaction mixture was inhibited by tryptamine (91% inhibition), as well as by indole-3-carboxylic acid and indomethacin (80% and 77% inhibition, respectively). Lipid peroxidation with tert-butyl hydroperoxide as a source of radicals was followed by the formation of thiobarbituric acid reactive substances. Tested drugs inhibited lipid peroxidation in the order: tryptamine (59%) > indole-2-carboxylic acid (38%) > indomethacin (26%) > melatonin and indole-3-carboxylic acid (13%). In vivo, alloxan-induced hyperglycaemia was reduced in mice pretreated with drugs tested. The highest protective effect was observed with indomethacin (52% inhibition), followed by tryptamine and melatonin (18% and 16% inhibition, respectively).
authors.affiliation: Institute of Experimental Biopharmaceutics, Joint Research Center of the Academy of Sciences of the Czech Republic and PRO.MED.CS Praha, Hradec Králové. stetinova@uebf.cas.cz
authors.forename: V
authors.initials: V
authors.lastname: Stetinová
authors.forename: L
authors.initials: L
authors.lastname: Smetanová
authors.forename: V
authors.initials: V
authors.lastname: Grossmann
authors.forename: P
authors.initials: P
authors.lastname: Anzenbacher
mesh_terms: D000496:Alloxan; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002264:Carboxylic Acids; D005260:Female; D006820:Hyaluronic Acid / Q000378:metabolism; D006943:Hyperglycemia / Q000139:chemically induced / Q000188:drug therapy*; D066298:In Vitro Techniques; D007211:Indoles / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D007213:Indomethacin / Q000737:chemistry / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008099:Liver / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D008550:Melatonin / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D010100:Oxygen / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values; D013329:Structure-Activity Relationship; D014363:Tryptamines / Q000737:chemistry / Q000378:metabolism
chemical_list: D000975:Antioxidants; D002264:Carboxylic Acids; D007211:Indoles; D014363:Tryptamines; C058980:indole-2-carboxylic acid; C030820:tryptamine; D008315:Malondialdehyde; C012382:indole-3-carboxylic acid; D000496:Alloxan; D006820:Hyaluronic Acid; D008550:Melatonin; D010100:Oxygen; D007213:Indomethacin