Trypanocidal Activity and Genetic Toxicity of the Ethanolic Extract of Smallanthus sonchifolius (Poepp. & Endl.) H. Rob.

ULLOA J; URBANO K; REDKO F; MOREIRA SZOKALO R ; PETRAY PB; CATALAN CA; CARBALLO MA; FRANK FM; MUSCHIETTI LV

., Carballo Marta A., Frank Fernanda, Muschietti Liliana.

Congreso; VIII International Phytocosmetics and Phytotherapy Congress; 2018

International Society for Phytocosmetic Science (ISPS).

Chagas disease is a life-threatening disease caused by the parasite Trypanosoma cruzi, which is mainly found in endemic areas of Latin America. The options for its treatment are limited to two drugs: benznidazole and nifurtimox which, due to their toxicity and low efficacy, make necessary the search of new therapeutic alternatives. In previous works, our group has isolated and identified, from the species Smallanthus sonchifolius, six sesquiterpene lactones with promising in vitro and in vivo trypanocidal activity. The aim of this work was to study the trypanocidal activity of the ethanolic extract (SSEE) of this plant and its toxicity in order to evaluate its potential as an herbal medicine.The antiparasitic activity of SSEE was evaluated on the epimastigote, trypomastigote and amastigote forms of T. cruzi in a range between 0-100 μg/ml. Cytotoxicity was assessed by the MTT assay in Vero and CHO-K1 cells, while the comet assay was used as a genotoxicity screening. In order to study the mechanism of action of the extract, epimastigotes treated with SSEE were stained with acridine orange and observed under a fluorescence microscope. Each determination was made with the corresponding positive control.The values of inhibitory concentration 50 (IC50) obtained against the different forms of the parasite were between 7.38-20.68 μg/ml while those of cytotoxic concentration 50 (CC50) were 108.84 μg/ml (Vero) and 41.3 μg/ml (CHO-K1). In the treated parasites the induction of apoptosis-like cell death was observed in the tested concentrations (IC50 - IC90), detecting the formation of acidic bodies potentially linked to this process. At the highest concentration of the extract (IC90), the parasites showed a color pattern similar to the positive control. The comet test showed a genotoxic effect at a concentration of 15 μg/ml.The preliminary results found allowed us to conclude that SSEE is active against the different stages of T. cruzi. However, given the results obtained from genotoxicity, risk/ benefit relationship must be established prior to their use as a potential herbal medicine.