Plasma coenzyme Qconcentration, antioxidant status, and serum N-terminal pro-brain natriuretic peptide concentration in dogs with various cardiovascular diseases and the effect of cardiac treatment on measured variables.

Abstract

OBJECTIVE To determine the plasma total antioxidant capacity, erythrocyte superoxide dismutase activity, whole blood glutathione peroxidase activity, and plasma coenzyme Q(CoQ) concentration in dogs with various stages of cardiovascular diseases and in healthy dogs; assess the influence of cardiac treatment on the levels of antioxidant variables, plasma CoQconcentration, and serum N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration, and determine any correlation between the disease severity (NT-proBNP concentration) and antioxidant variables or CoQconcentration. ANIMALS 43 dogs with various types and stages of cardiovascular diseases (congenital and acquired) and 29 healthy dogs. PROCEDURES Blood samples were collected from all dogs for spectrophotometric assessment of antioxidant variables. Plasma CoQconcentration was determined with a high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry method. Serum NT-proBNP concentration was measured with an ELISA. RESULTS Values for antioxidant variables did not differ among groups of dogs with cardiovascular diseases, regardless of disease stage or treatment. Plasma CoQconcentration was significantly increased in treated dogs with congestive heart failure (CHF), compared with untreated patients. However, plasma CoQconcentration did not differ among heart failure classes. A significant, negative correlation between serum NT-proBNP and plasma CoQconcentrations was identified in treated CHF-affected dogs, suggesting that low plasma CoQconcentration may be associated with increased severity of CHF. CONCLUSIONS AND CLINICAL RELEVANCE The antioxidant variables evaluated were not altered in dogs with CHF, regardless of cardiac disease stage or treatment. Further investigation into the possible effects of CoQsupplementation in dogs with advanced stages of CHF is warranted.