Search for antiprotozoal compounds in Gymnocoronis spilanthoides (asteraceae).

SELENER M; GUSTAVO GIBERTI; CAZORLA SI; AUGUSTO E BIVONA; VIRGINIA SUSANA MARTINO; VALERIA PATRICIA SULSEN; NATACHA CERNY; EMILIO L MALCHIODI; REDKO FLAVIA

Bogota

Congreso; 3rd Research Network Natural Products against Neglected Diseases ? ResNet NPND Scientific Meeting; 2016

American trypanosomiasis or Chagas´ disease is an endemic parasitic disease caused by Trypanosoma cruzi. This parasitosis affects 6-7 million people worldwide and it is distributed principally in Latin America but it is also found in developing countries such as United States, Canada and European countries [1]. In Argentina is estimated that approximately 1.5 million people are infected. Treatment with nifurtimox and benznidazole has limitations due to their host toxicity, side effects and low efficacy.Nature has provided useful drugs that are used nowadays to treat different pains. Asteraceae species have been a rich source of active compounds and have been attractive for drug discovey. In previous work we have demonstrated the trypanocidal activity of the dichcloromethane extract of Gymnocoronis spilanthoides (Asteraceae) [2]. Therefore, the aim of this investigation was to isolate the compounds responsable for its bioactivity.The dichcloromethane extract of G. spilanthoides was purified by liquid-liqud partion with hexane and fractionated by column chromatography with Silicagel and eluted with a gradient of CH2Cl2 and EtoAc. A compound (A) was isolated from fractions eluted with CH2Cl2:EtoAc (2:1). This compound was characterized by thin layer chromatography and infrared spectrum. The trypanocidal activity of A was evaluated on T. cruzi epimastigotes (RA) by the [3H]-thymidine uptake assay. The effect of this compound on mammalian cells was assessed by MTT assay using HEK-293 cells. The compound A showed trypanocidal activity (IC50= 1.6 µg/ml) with slow toxicity to mammalian cells (CC50> 200 µg/ml). This compound presented absorptions of carbonyls at 1727 and 1692 cm-1 in the infrared spectrum that could be related to the presence of ester and α,β-unsaturated ketone groups, respectively. A trypanocidal compound was isolated from G. spilanthoides. The evaluation of the effect of compound A on infective and intracellular forms of T. cruzi will be carried on. Besides, NMR and MS spectra will be done in order to elucidate its structure.Keywords: Chagas´ disease, Gymnocoronis spilanthoides, AsteraceaeAcknowledgements: This work was supported by grants from PICT 2011-1753 (The National Agency for Science and Technology Promotion), PIP 0324 (National Scientific and Technical Research Council), and UBACYT 20020130200270(University of Buenos Aires).References[1] World Health Organization 2016. Fact sheet Chagas disease (American trypanosomiasis). http://www.who.int/mediacentre/factsheets/fs340/en/. Accessed August 2016.[2] Selener M, et al., 2014. 14th International Congress of Ethnopharmacology. VIII Simposio Internacional de Química de Productos Naturales y sus Aplicaciones. Talca, Chile.