A trypanocidal sesquiterpene lactone isolated from Stevia satureiifolia var. satureiifolia

BORGO J; BIVONA A; BEER MF; CERNY N; CABRAL M; HERNANDEZ N; SANCHEZ ALBERTI A; MALCHIODI E; CATALAN C; MARTINI F; SÜLSEN V

Berlín

Simposio; ResNet NPND (Reseachers Network-Natural Products for Neglected Diseases) 10th Anniversary Simposium; 2021

American trypanosomiasis or Chagas disease is an endemic parasitosis caused by the protozoanTrypanosoma cruzi that affects 6 to 7 million people worldwide, mostly in Latin America and isresponsible for more than 10000 deaths per year [1]. Benznidazole and nifurtimox are the onlyavailable drugs for its treatment. These antiparasitic drugs were developed half a century ago andpresent variable efficacy and fairly common side effects. Consequently, new therapeutic agents totreat this disease are urgently needed.As a result of our ongoing research on antiparasitic compounds from Stevia species, we have reportedthe trypanocidal activity of the organic extract of S. satureiifolia var. satureiifolia (Asteraceae) and theisolation of the active flavonoids eupatorin and 5-desmethylsinensetin [2]. Based on these results, wehave continued the study of this extract in the search of other bioactive compounds.Dried aerial parts of S. satureiifolia var. satureiifolia were extracted by maceration withdichloromethane. Fractionation of this extract was performed by column chromatography usingSilicagel and a gradient of dichloromethane:EtOAc. Seven fractions (FA to FG) were obtained. Thepurification of fraction D (FD), eluted with dichloromethane:EtOAc (2:1), afforded a precipitate(compound A). The purity of the compound was assessed by chromatographic techniques and thestructure elucidation was performed by spectroscopic methods. The compound was identified as agermacranolide type sesquiterpene lactone. The in vitro activity of this sesquiterpene lactone againstT. cruzi epimastigotes and amastigotes was tested, resulting in IC50 values of 1.75 and 6.33 μg/ml,respectively. Evaluation of the activity against trypomastigote forms of the parasite, which constitutesthe predominant form in the acute phase of the disease, is currently in progress.