Homocysteine Concentration in the Serum of Dogs Naturally Infected with <i>Leishmania</i> Spp. – Association with the Stage of the Disease, Therapy, and Clinical Pathology Data

Abstract Progressive tissue injury in canine leishmaniosis (CL) is related to the deposition of immune complexes, which induces vasculitis and leads endothelial dysfunction. Homocysteine (Hcy) increase may worsen dysfunction, but data concerning its concentration different CL stages links acute phase response oxidative stress are missing. We compared Hcy levels between dogs with mild (N=24) moderate without treatment (N=17) treated anti- Leishmania drugs vitamin B supplements (N=9). Dogs CL, regardless therapy administration, had more distinct clinical signs, lower erythron values, a higher level acute-phase proteins (APPs), IgG against spp., urea creatinine, than CL. values did not differ stages, lowest Hcy. An inverse relationship existed stage, therapy, IgG, pathology data. The only positive state. disease stage therapeutic intervention were level, except case paraoxonase-1/Hcy ratio, indicating favorable conditions for antioxidative defense dogs. In conclusion, changes indicated possible involvement dysfunction evaluated by APPs. Finally, might be an early marker endothelium recovery