title: Evaluation of oxidative stress in the anemia of dogs with chronic kidney disease.
abstract: BACKGROUND
  Anemia and systemic oxidative stress may occur in dogs with chronic kidney disease (CKD). Only scarce information regarding the intraerythrocytic redox status under these conditions is available at this time.
  
  
  OBJECTIVE
  The aim of this study was to evaluate the indicators of oxidative stress and intraerythrocytic antioxidant defense in dogs with anemia of CKD.
  
  
  METHODS
  Thirty dogs with CKD in stages 3 or 4 with nonregenerative anemia (HCT ≤ 37%) were compared to 20 healthy dogs. Complete blood count, reticulocyte %, blood smear evaluation, intraerythrocytic concentrations of total (GSHt), reduced (GSH), and oxidized glutathione (GSSH), and activities of glutathione peroxidase, glutathione reductase and superoxide dismutase (SOD), as well as plasma concentrations of thiobarbituric acid-reactive substances (TBAR) were determined.
  
  
  RESULTS
  Anemia of CKD dogs was nonregenerative (reticulocytes ≤ 0.2% with scarce anisocytosis and poikilocytosis). Intraerythrocytic GSSH and SOD, and plasma TBAR were higher in dogs with CKD. There was a positive correlation between the creatinine concentration and TBAR, and negative correlations between creatinine concentration and HCT, as well as between HCT and TBAR. In CKD dogs with a higher degree of anemia, SOD levels were higher and GSSH concentrations were lower. Despite the evidence of increased systemic oxidative stress, the compensatory response of SOD and the sustained intraerythrocytic concentrations of GSSH in CKD dogs with anemia indicated that the erythrocytes maintained the antioxidant defense.
  
  
  CONCLUSIONS
  There was no strong evidence that oxidative stress was associated with higher degrees of anemia in dogs with CKD.
authors.affiliation: Department of Veterinary Internal Medicine, School of Veterinary Medicine and Animal Science, São Paulo-SP, Brazil.
authors.forename: Marcia M
authors.initials: MM
authors.lastname: Kogika
authors.forename: Marcio D
authors.initials: MD
authors.lastname: Lustoza
authors.forename: Mitika K
authors.initials: MK
authors.lastname: Hagiwara
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Caragelasco
authors.forename: Cinthia R
authors.initials: CR
authors.lastname: Martorelli
authors.forename: Clara S
authors.initials: CS
authors.lastname: Mori
mesh_terms: D000740:Anemia / Q000503:physiopathology / Q000662:veterinary*; D000818:Animals; D000975:Antioxidants / Q000032:analysis; D004285:Dogs; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood; D005980:Glutathione Reductase / Q000097:blood; D008297:Male; D018384:Oxidative Stress; D051436:Renal Insufficiency, Chronic / Q000503:physiopathology / Q000662:veterinary*; D013482:Superoxide Dismutase / Q000097:blood; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis
chemical_list: D000975:Antioxidants; D017392:Thiobarbituric Acid Reactive Substances; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase
keywords: Canine; erythrocyte; glutathione; superoxide dismutase; uremia