Assessment of degree of oxidative stress and antioxidant concentrations in dogs with idiopathic dilated cardiomyopathy.

OBJECTIVE: To assess degree of oxidative stress and antioxidant concentrations in dogs with idiopathic dilated cardiomyopathy (IDCM). DESIGN: Prospective study. ANIMALS: 18 dogs with IDCM and 16 healthy control dogs. PROCEDURE: Concentrations of malondialdehyde (an indicator of oxidative stress); vitamins A, C, and E; glutathione peroxidase; and superoxide dismutase were measured. RESULTS: Glutathione peroxidase concentration was significantly increased in dogs with IDCM, compared with control dogs. Vitamin A and superoxide dismutase concentrations were not significantly different between groups. A negative correlation was found between disease severity and plasma vitamin E concentration. Disease severity was not correlated with concentrations of other antioxidants. Medications did not significantly affect oxidant or antioxidant concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: The change in glutathione peroxidase concentration and the correlation between vitamin E concentration and disease severity suggest that the oxidant-antioxidant system may play a role in development of IDCM.