Genetic analysis comparison of glutathione s-transferase in Fasciola hepatica of different hosts. Its implications on the phenomenon of anthelmintic resistance

FERNÁNDEZ V.; MIRANDA-MIRANDA E.; SOLANA H.

Mexico DF

Congreso; 13th International Congress of Parasitology ICOPA XIII; 2014

The Mexican Society of Parasitology and the World Federation of Parasitologists The Mexican Society of Parasitology and the World Federation of Parasitologists

BACKGROUND: Fasciolasis is a zoonotic parasitic disease caused by Fasciola hepatica and its control is mainly based on the use of triclabendazole (TCBZ). Parasite resistance to different anthelmintics is growing worldwide, including the resistance of F. hepatica to TCBZ. In fasciolosis exist the phenomenon of cross-infection in which the coexistence of cattle, sheep and pigs allows the parasitic passage between species. These passages determine changes in adaptation to the new environment in which could be encouraged the resistance phenomenon. Glutathion S-Transferases (GSTs) in F. hepatica are major detoxification enzymes in adult helminthes. Recently we have demonstrated that the fluke TCBZ resistant (Sligo strain) expressed significatively major GST metabolic activity compared to that from susceptible flukes (Cullompton Strain). That enhanced metabolic obtained activity correlates with overexpression of mRNA for GST and the presence of two transversionals mutations in the genGST in Sligo strain (TCBZ-R). In this work we  comparatively characterized the gene for F. hepatica GST (genGST) and the expression of the corresponding mRNA from three different hosts (sheep, cattle and pig) compared against Sligo (TCBZ-R) strain and Cullompton (TCBZ-S) strain. METHODS: Purification of total RNA was using Trizol ®. The RT-PCR was performed with SIGMA-TRI REAGENT ® (T 9414) kit. The comparison analysis of genGST sequences of cattle, sheep and pigs were performed using CLUSTAL2. RESULTS: The flukes from the three host species expressed identical to the corresponding genGST TCBZ-S (Cullomptom strain). The expressed F. hepatica GST RNA transcripts from all three host species showed significant differences (pig 2>bovine1.7>sheep1). CONCLUSIONS: These differences in expression are directly related to the degree of resistance of different hosts against fasciolosis contributing to the understanding of the mechanisms that generate resistance in different definitive hosts of this disease.