Inmunolocalization of certain detoxifying proteins in Fasciola hepatica: relationship with resistance mechanisms

Abstract

Fasciolasis, is an emergent zoonotic disease. The drug of choice for its treatment is triclabendazole (TCBZ). Today, the extensive use of TCBZ has already generated resistance. The mechanisms of anthelmintic resistance include involvement of detoxification processes generated through the FMO enzymatic pathway or through drug extrusion pumps such as the P Glycoprotein (P Gp). The aim of the present work was to immune-locate the presence and distribution of P-Gp and FMO in TCBZ susceptible and resistant Fasciola hepatica. The immunohistochemical study confirmed the presence of P Gp in both strains, distributed in the enterocytes and a smaller quantity in the vitellogenic cells and specula. FMO location seems to be restricted to the vitellogenic cells. This distribution pattern was similar for both strains, without differences in their distribution and expression. It is inferred that the resistance may involve modifications at metabolic levels, without detectable morphologic changes, at least not observable by optical microscopy.