Glutathione Peroxidase Activity, Plasma Total Antioxidant Capacity, and Urinary F2- Isoprostanes as Markers of Oxidative Stress in Anemic Dogs.

Abstract

BACKGROUND: Oxidative stress plays a role in the pathophysiology of several diseases and has been documented as a contributor to disease in both the human and veterinary literature. One at-risk cell is the erythrocyte, however, the role of oxidative stress in anemia in dogs has not been widely investigated. HYPOTHESIS/OBJECTIVE: Anemic dogs will have an alteration in the activity of glutathione peroxidase (GPx), a decrease in of total antioxidant capacity (TAC), and an increased concentration of urinary 15-F-isoprostanes (F-IsoP) when compared to healthy dogs. ANIMALS: 40 client-owned dogs with anemia (PCV <30%) age-matched to 40 client-owned healthy control dogs. METHODS: Prospective, cross-sectional study. Whole blood GPx activity, plasma TAC, and urinary F-isoprostane concentrations were evaluated in each dog and compared between groups. RESULTS: Anemic dogs had significantly lower GPx activity (43.1 &#xd7; 10+/- 1.6 &#xd7; 10U/L) than did dogs in the control group (75.8 &#xd7; 10+/- 2.0 &#xd7; 10U/L; P < 0.0001). The GPx activity in dogs with hemolysis (10+/- 0.8 &#xd7; 10U/L) was not significantly different (P = 0.57) than in dogs with nonhemolytic anemia (43.5 &#xd7; 10+/- 1.1 &#xd7; 10U/L). The TAC concentrations (P = 0.15) and urinary F-isoprostanes (P = 0.73) did not significantly differ between groups. CONCLUSIONS AND CLINICAL IMPORTANCE: Glutathione peroxidase activity was significantly decreased in anemic dogs indicating oxidative stress. Additional studies are warranted to determine if antioxidant supplementation would improve survival and overall outcome as part of a therapeutic regimen for anemic dogs.