title: Antioxidant properties of bucillamine: possible mode of action.
abstract: The antioxidant properties of Bucillamine (BUC), a di-thiol compound used for treatment of rheumatoid arthritis (RA) and its possible mode of action, were investigated. BUC exhibits potent antioxidant activity similar to those of trolox and ascorbic acid. It reduces the stable free radical diphenyl-2-picrylhydrazyl (DPPH) with IC(50) of 18.5+/-0.1 micromol, its relative antioxidant activity by the ferric reducing ability (FRAP) is 2.07+/-0.01 mM and by the trolox equivalent antioxidant capacity (TEAC), 1.46+/-0.05 mM. However, its superoxide and apparent hydroxyl radical scavenging activities are low (IC(50) at millimolar concentrations). We found that BUC is a strong iron (II) and copper (II) chelator. This finding is very important since these metal ions are significantly higher in RA patients and may be involved in oxidative stress-induced damage. Our study suggests that BUC is a potent antioxidant which exerts its beneficial therapeutic activities in RA patients by metal chelation rather than by scavenging free radical species.
authors.affiliation: Experimental Hematology, Department of Physiology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel. daliama@bgumail.bgu.ac.il <daliama@bgumail.bgu.ac.il>
authors.forename: Dalia
authors.initials: D
authors.lastname: Mazor
authors.forename: Liya
authors.initials: L
authors.lastname: Greenberg
authors.forename: Dror
authors.initials: D
authors.lastname: Shamir
authors.forename: Dan
authors.initials: D
authors.lastname: Meyerstein
authors.forename: Naomi
authors.initials: N
authors.lastname: Meyerstein
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D002614:Chelating Agents / Q000494:pharmacology; D003300:Copper / Q000737:chemistry; D003545:Cysteine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004563:Electrochemistry; D005609:Free Radicals / Q000737:chemistry; D010084:Oxidation-Reduction / Q000187:drug effects; D013057:Spectrum Analysis
chemical_list: D000975:Antioxidants; D002614:Chelating Agents; D005609:Free Radicals; D003300:Copper; D003545:Cysteine; C026535:bucillamine