Antioxidant actions of ovothiol-derived 4-mercaptoimidazoles: glutathione peroxidase activity and protection against peroxynitrite-induced damage.
4-Mercaptoimidazoles derived from the naturally occurring antioxidants, ovothiols, were tested for their glutathione peroxidase-like (GSH Px-like) activity and protection against peroxynitrite-induced damage. All the thiol compounds displayed similar significant GSH Px-like activities, which are however weaker than that of the reference compound, ebselen. The inhibitions of the peroxynitrite-dependent oxidation of Evans blue dye and dihydrorhodamine 123 showed that the thiol compounds substituted on position 5 of the imidazole ring were nearly as effective as ebselen while the C-2 substituted ones were less effective. Both assays corroborate the large superiority of mercaptoimidazoles over glutathione as inhibitors of peroxynitrite-dependent oxidation.
Bailly
F
F
Laboratoire de Chimie Organique Physique, ESA CNRS 8009, Villenuve d'Ascq, France. fabrice.bailly@univ-lille.fr
Zoete
V
V
Vamecq
J
J
Catteau
J P
JP
Bernier
J L
JL
D000975:Antioxidants / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001393:Azoles / Q000378:metabolism / Q000494:pharmacology; D002384:Catalysis / Q000187:drug effects; D002839:Chromans / Q000378:metabolism / Q000494:pharmacology; D005070:Evans Blue / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism / Q000494:pharmacology; D005979:Glutathione Peroxidase / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism; D007093:Imidazoles / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D054833:Isoindoles; D007700:Kinetics; D008762:Methylhistidines / Q000378:metabolism*; D009249:NADP / Q000378:metabolism; D009566:Nitrates / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000494:pharmacology; D016566:Organoselenium Compounds / Q000378:metabolism / Q000494:pharmacology; D016877:Oxidants / Q000037:antagonists & inhibitors / Q000378:metabolism / Q000494:pharmacology; D010084:Oxidation-Reduction / Q000187:drug effects; D012235:Rhodamines / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology
D000975:Antioxidants; D001393:Azoles; D002839:Chromans; D016166:Free Radical Scavengers; D007093:Imidazoles; D054833:Isoindoles; D008762:Methylhistidines; D009566:Nitrates; D016566:Organoselenium Compounds; D016877:Oxidants; D012235:Rhodamines; D013438:Sulfhydryl Compounds; C050085:ovothiol C; C058319:dihydrorhodamine 123; C039642:peroxynitric acid; C042986:ebselen; D005070:Evans Blue; D009249:NADP; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase; D005978:Glutathione; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid