Revista Parasitología Latinoamericana
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Trabajo de incorporación - SOCHIPA
Elucidating the antiparasitic activity of an anthelmintic forage and its bioactive metabolites: Cichorium intybus
MIGUEL PEÑA-ESPINOZA1 AND RODRIGO LÓPEZ-MUÑOZ
1
Instituto de Farmacologia y Morfofisiologia, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
Fondecyt Postdoctorado #3170875 (CONICYT, Chile)
Correspondencia:
[email protected]
Recibido: 25.10.2018
Aceptado: 25.10.2018
Parasitología Latinoamericana. (2018); 67 (2): 20-22
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Revista Parasitología Latinoamericana
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Background The rising development of drug-resistance in parasitic nematodes infecting livestock worldwide warrants the development of novel parasite control approaches1. One strategy under investigation is the use of bioactive plants with anthelmintic activity as new antiparasitic compounds. Chicory (Cichorium intybus) is a bioactive forage that has been increasingly investigated due to its anthelmintic activity against livestock nematodes2. Chicory synthesises sesquiterpene lactones (SL), which are known to exert potent biological activities and therefore are believed to be the responsible anthelmintic compounds in chicory2. Previously, it has been reported that SL-extracts from different chicory cultivars can induce distinct anthelmintic activity in vitro, which could help the identification of the precise antiparasitic molecules. In addition, no previous studies have evaluated whether chicory has activity against drug-resistant nematodes.
IVM-resistant mutant (avr-14(ad1305) I; avr15(ad1051); DA1302) were used. The inhibitory effect of chicory SL on worm motility were investigated in C. elegans drug-sensitive placed in 96 well-plates (n=10 worms/well) by exposing synchronised L4 worms to decreasing concentrations of SL-extracts ranging from 2000 to 125 µg/mL plates (final concentration 1% ethanol in well). Worms were incubated at 1% etanol or 10 µg IVM/mL as negative and positive controls, respectively. After 24 h of incubation, all nematodes in each well were observed under an inverted microscope and classified as motile or non-motile (no movement observed in 10 s). C. elegans IVMresistant (synchronised L4) were incubated at similar conditions as above, but after 24 of incubation, the worm motility was evaluated by counting the number of body bends of each worm in liquid media for 30 s. A body bend was defined as a full sinusoid movement of a worm, in which the head of the worm moved from one angle to the opposite angle, and then returned to its original angle.
Objective
Preliminary results
The aim of our ongoing project is to further explore the anthelmintic effects of chicory by comparing the activity of SL-extracts from different chicory cultivars and geographical regions in drug-sensitive and drug-resistant nematodes.
In studies with drug-sensitive C. elegans, three chicory extracts induced a dose-dependent inhibition of worm motility (Fig. 1A). Based on the effective concentraton to inhibit the movement in 50% of the exposed worms (EC50), the root pulp and Spadona2013 extracts exerted the most potent anthelmintic effects (EC50: root pulp = 646 µg/mL; Spadona-2013 = 868 µg/mL; Spadona-2016 = 1114 µg/mL; Choice2016 = not determined). In the studies with IVMresistant C. elegans, the root pulp and Spadona-2013 extracts were also the more active extracts against these drug-resistant worms (Fig. 1B), inducing a significant reduction in the movement of exposed worms, in comparison with the other treatments at the same concentrations (P
