title: Influence of tiopronin, captopril and levamisole therapeutics on the oxidative degradation of hyaluronan.
abstract: The ability to protect hyaluronic acid (HA) from oxidative degradation by cupric ions and ascorbate (production of (•)OH and peroxy-type radicals) during acute phase joint inflammation has been investigated using the following drugs: tiopronin, captopril, and levamisole. Radical scavenging activity, i.e. the propensity for donation of electrons was assessed for the drugs by ABTS and DPPH assays. The kinetics of HA degradation have been measured in the presence of each drug using rotational viscometry. The results of ABTS and DPPH assays show the highest radical scavenging activity for captopril, followed by tiopronin. For levamisole, no effect was observed. Captopril and tiopronin prevented HA degradation induced by (•)OH radicals in a similar manner, while tiopronin was more effective in scavenging peroxy-type radicals. On the other hand, levamisole was shown to be a pro-oxidant. Recovered HA fragments were characterized using FT-IR analysis, the incorporation of a sulphur atom from captopril and tiopronin but not from levamisole into the HA molecule was demonstrated.
authors.affiliation: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Slovakia.
authors.forename: Katarína
authors.initials: K
authors.lastname: Valachová
authors.affiliation: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Slovakia.
authors.forename: Mária
authors.initials: M
authors.lastname: Baňasová
authors.affiliation: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Slovakia.
authors.forename: Dominika
authors.initials: D
authors.lastname: Topoľská
authors.affiliation: Institute of Chemistry, Slovak Academy of Sciences, Slovakia.
authors.forename: Vlasta
authors.initials: V
authors.lastname: Sasinková
authors.affiliation: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Slovakia.
authors.forename: Ivo
authors.initials: I
authors.lastname: Juránek
authors.affiliation: Stokes Laboratories, University of Limerick, Ireland. Electronic address: Maurice.Collins@ul.ie.
authors.forename: Maurice N
authors.initials: MN
authors.lastname: Collins
authors.affiliation: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, Slovakia.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Šoltés
mesh_terms: D052160:Benzothiazoles / Q000737:chemistry; D001713:Biphenyl Compounds / Q000737:chemistry; D002216:Captopril / Q000737:chemistry / Q000494:pharmacology; D004579:Electron Transport / Q000187:drug effects; D016166:Free Radical Scavengers / Q000737:chemistry / Q000494:pharmacology*; D006820:Hyaluronic Acid / Q000378:metabolism*; D007700:Kinetics; D007978:Levamisole / Q000737:chemistry / Q000494:pharmacology; D010851:Picrates / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry; D008625:Tiopronin / Q000737:chemistry / Q000494:pharmacology; D014783:Viscosity
chemical_list: D052160:Benzothiazoles; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; D013451:Sulfonic Acids; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D007978:Levamisole; D006820:Hyaluronic Acid; D002216:Captopril; D008625:Tiopronin; C004931:1,1-diphenyl-2-picrylhydrazyl
keywords: Hyaluronan; Oxidative degradation; Rotational viscometry; SH group