Ultrastructural changes in the tegument and tissues of Fasciola hepatica adults and their eggs due to the effect of an ethyl acetate extract of Artemisia ludoviciana Nutt. spp mexicana

Abstract

The objective of the present work was to evaluate the effect of an ethyl acetate extract of Artemisia ludoviciana on the viability of adult Fasciola hepatica parasites and eggs. Ovicidal assays were performed at concentrations of 100, 200, 300, 400 and 500 mg/L Artemisia ludoviciana extract. Bioassays of fasciolicidal efficacy in adult specimens of F. hepatica were performed at extract concentrations of 125, 250, 375 and 500 mg/L. The effects of triclabendazole, a reference drug, and artemisinin were also evaluated. The ovicidal effectiveness of the extracts obtained after 16 h of incubation at concentrations of 100, 200, 300, 400 and 500 mg/L was 48%, 52%, 87%, 89% and 92%, respectively (p < 0.05), and the fasciolicidal efficiencies during the first 24 h posttreatment ranged from 82–100% (p < 0.05). In both cases, scanning electron microscopy revealed damage to the shells of the eggs treated with the extract, compromising their stability. In adult fasciolae, alterations to the integument that resulted in its erosion and detachment were observed. Histopathological studies of the affected specimens revealed damage to the tegumentary and subtegumentary cells and alterations in the ovaries, testicles and intestine. This damage was more severe after treatment with the extract than after treatment with the other compounds.