title: In vitro study of the antioxidant properties of nimesulide and 4-OH nimesulide: effects on HRP- and luminol-dependent chemiluminescence produced by human chondrocytes.
abstract: OBJECTIVE
  Reactive oxygen species (ROS) are now recognized to play an important role in the pathogenesis of rheumatic diseases and constitute an interesting therapeutic target for drugs. This in vitro study was designed to evaluate the antioxidant properties of nimesulide (NIM), a nonsteroidal antiinflammatory drug of the sulfonanilide class, and its main metabolite 4-OH nimesulide (4-OHNIM).
  
  
  METHODS
  The scavenging effects of NIM and 4-OH NIM on hydroxyl radical ((.)OH) and superoxide anions (O(minusd)(2)) were investigated by electron spin resonance (ESR), using 5, 5-dimethylpyrroline-N-oxide (DMPO) as the spin trap agent. The quenching properties of these drugs on hypochlorite anion was studied by luminol enhanced chemiluminescence. Finally, the effects of NIM and 4-OHNIM on the reactive oxygen species production by human articular chondrocytes were recorded by HRP and luminol-enhanced chemiluminescence.
  
  
  RESULTS
  By this method it has been demonstrated that NIM and 4-OHNIM, at concentrations ranging from 10 to 100 microM, are potent scavengers of(.)OH whereas only 4-OHNIM was capable to scavenge O(minusd)(2). Chemiluminescence generated by HOCl was also significantly and dose-dependently inhibited by both NIM and 4-OHNIM. Nevertheless, at each concentration tested, the inhibitory effect of 4-OHNIM was significantly more marked, even at the highest concentration (100 microM). Furthermore, when chondrocytes were pre-incubated for 48-96 h with NIM or 4-OHNIM, the luminol- and HRP-dependent CL produced by the cells was significantly inhibited in a dose-dependent manner.
  
  
  CONCLUSIONS
  NIM and 4-OHNIM may protect cartilage against oxidative stress, not only by scavenging ROS but also by inhibiting their production by chondrocytes.
authors.affiliation: Bone and Cartilage Metabolism Research Unit, Institute of Pathology, University of Liège, Belgium.
authors.forename: S X
authors.initials: SX
authors.lastname: Zheng
authors.forename: A
authors.initials: A
authors.lastname: Mouithys-Mickalad
authors.forename: G P
authors.initials: GP
authors.lastname: Deby-Dupont
authors.forename: C M
authors.initials: CM
authors.lastname: Deby
authors.forename: A P
authors.initials: AP
authors.lastname: Maroulis
authors.forename: A H
authors.initials: AH
authors.lastname: Labasse
authors.forename: M L
authors.initials: ML
authors.lastname: Lamy
authors.forename: J M
authors.initials: JM
authors.lastname: Crielaard
authors.forename: J Y
authors.initials: JY
authors.lastname: Reginster
authors.forename: Y E
authors.initials: YE
authors.lastname: Henrotin
mesh_terms: D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D002358:Cartilage, Articular / Q000166:cytology; D018929:Cell Culture Techniques; D019902:Chondrocytes / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D016166:Free Radical Scavengers / Q000494:pharmacology; D006735:Horseradish Peroxidase / Q000494:pharmacology; D006801:Humans; D017665:Hydroxyl Radical / Q000494:pharmacology; D008163:Luminescent Measurements; D008165:Luminol / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D013449:Sulfonamides / Q000494:pharmacology*; D013481:Superoxides / Q000494:pharmacology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D000975:Antioxidants; D016166:Free Radical Scavengers; D013449:Sulfonamides; D013481:Superoxides; D017665:Hydroxyl Radical; D008165:Luminol; D006735:Horseradish Peroxidase; C012655:nimesulide