In vitro anthelminthic activity of Stevia multiaristata dichloromethane extract on Echinococcus granulosus protoscoleces.

ALBANI CLARA MARÍA; BORGO JIMENA; HERNANDEZ N.; FABBRI JULIA; PENSEL, PATRICIA; FASCIANI LARA; MARTINI F.; PALADINI A.; SÜLSEN VALERIA; ELISSONDO MARIA CELINA

Buenos Aires

Congreso; Reunión annual de sociedades de biociencias SAIC-SAI-SAFIS.; 2020

Cystic echinococcosis (CE) is a worldwide zoonotic disease caused by the larval stage of the parasite Echinococcus granulosus, which causes long-term infections in humans and animals, being a serious public health problem. Albendazole, the main drug used against CE, has undesirable side effects and their efficacy is about 50%. Thus, new treatment alternatives are urgently needed. In the last few decades, there has been an increased interest in studying the anthelmintic activity of natural products. Plants from Stevia genus (Asteraceae) are a potential source of antiprotozoal and antimicrobial compounds. The antiparasitic activity of extracts from different Stevia species has recently been demonstrated on Trypanosoma cruzi and Leishmania braziliensis. In the current study, we demonstrated the in vitro efficacy of the Stevia multiaristata dichloromethane extract against protoscoleces of E. granulosus. Viable and free protoscoleces were treated with 100, 50, 10 and 5 μg/ml of the extract. Culture tubes were followed microscopically every day. Viability assessment using the methylene blue exclusion test and ultrastructural studies with scanning electron microscope were performed. Control protoscoleces remained viable throughout the experimental period and no morphological changes were observed. The greatest protoscolicidal effect was observed with the concentrations of 100 and 50 μg/ml, where viability decreased rapidly to 0 % at days 6 and 9, respectively. The concentrations of 10 and 5 μg/ml reduced the viability to 50% between days 5 and 6. At day 1, the protoscoleces treated with 100 μg/ml showed soma contraction and at day 3 a total loss of morphology, total loss of microtriches, rostellar disorganization and presence of blebs in the tegument. In conclusion, S. multiaristata extract demonstrated a marked in vitro effect against E. granulosus larval stage.