Search for antiprotozoal compounds in Gymnocoronis spilanthoides (Asteraceae

SELENER M; CERNY N; BIVONA A; GIBERTI G; MACHIODI EL; MARTINO V; CAZORLA SI; REDKO F; SULSEN V

Congreso; ResNet NPND Scientific Meeting; 2016

American trypanosomiasis or Chagas' disease is an endemic parasitic disease caused by Trypanosoma cruzi. This parasitosisaffects 6-7 million people worldwide and it is distributed principally in LatinAmerica but it is also found in developing countries such as United States,Canada and European countries [1]. In Argentina is estimated that approximately 1.5million people are infected. Treatment with nifurtimox and benznidazole haslimitations due to their host toxicity, side effects and low efficacy.Nature has provided useful drugs that are used nowadays to treat differentpains. Asteraceae species have been a rich source of active compounds and havebeen attractive for drug discovey. In previous work we have demonstrated the trypanocidalactivity of the dichcloromethane extract of Gymnocoronisspilanthoides (Asteraceae) [2]. Therefore, the aim of this investigation was to isolatethe compounds responsable for its bioactivity.Thedichcloromethane extract of G.spilanthoides was purified by liquid-liqud partion with hexane and fractionatedby column chromatography with Silicagel and eluted with a gradient of CH2Cl2and EtoAc. A compound (A) was isolatedfrom fractions eluted with CH2Cl2:EtoAc (2:1). This compound wascharacterized by thin layer chromatography and infrared spectrum. Thetrypanocidal activity of A was evaluated on T.cruzi epimastigotes (RA) by the [3H]-thymidineuptake assay. The effect of this compound on mammalian cells was assessed byMTT assay using HEK-293 cells. The compound A showedtrypanocidal activity (IC50= 1.6 µg/ml)with slow toxicity to mammalian cells (CC50> 200 µg/ml). This compoundpresented absorptions of carbonyls at 1727 and 1692 cm-1 in the infraredspectrum that could be related to the presence of ester and α,β-unsaturated ketone groups, respectively. A trypanocidal compound wasisolated from G. spilanthoides. Theevaluation of the effect of compound A on infective and intracellular forms of T. cruzi will be carried on. Besides, NMRand MS spectra will be done in order to elucidate its structure.