Changes in serum biomarkers of oxidative stress after treatment for canine leishmaniosis in sick dogs

Canine leishmaniosis (CanL) is a zoonotic disease being endemic in several parts of the world. In this study we investigated the behavior of a panel of biomarkers of oxidative stress in 12 sick dogs naturally infected by CanL before and at days 30 and 180 of a successful therapy with a standard treatment. The assays total oxidant status (TOS), trolox equivalent antioxidant capacity (TEAC), ferric reducing ability of plasma (FRAP), cupric reducing antioxidant capacity (CUPRAC), serum thiol and paraoxonase 1 (PON1) were included in the panel. In addition, correlations between biomarkers of oxidative stress and inflammation (C-reactive protein (CRP) and ferritin) and urinary protein:creatinine ratio (UPC) were calculated. Serum CUPRAC, thiol and PON1 significantly increased after treatment and were negatively correlated with CRP, ferritin and UPC. This study demonstrates that biomarkers of oxidative stress, not previously studied in leishmaniosis such as CUPRAC and thiol, can change after a successful treatment for CanL showing a potential for use in monitoring the treatment of this disease.