Trypanocidal Activity of Smallanthus sonchifolius. Identification of Active Sesquiterpene Lactones by Bioassay-Guided Fractionation.

FERNANDA M. FRANK; ULLOA J; CAZORLA SI; MARAVILLA G; MALCHIODI, EMILIO L.; GRAU A; MARTINO, VIRGINIA; CATALAN, C; MUSCHIETTI, LILIANA

EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE

OXFORD UNIV PRESS

Lugar: Oxford; Año: 2013 vol. 6278 p. 1 - 10

1741-427X

In search for new plant-derived biologically active compounds against Trypanosoma cruzi we report the isolation of three known sesquiterpene lactones by bioassay-guided fractionation from the dichloromethane extract of Smallanthus sonchifolius. The compounds were identified by means of spectroscopic techniques as enhydrin (1), uvedalin (2) and polymatin B (3). These compounds showed a significant trypanocidal activity against the epimastigote forms of the parasite with IC50 of 0.84 M, 1.09 M and 4.90 M, respectively. Moreover, after 24 h of treatment with 10 µg/ml of enhydrin and uvedalin, the parasites could not recover their replication rate. Against T. cruzi trypomastigotes, 1 and 2 showed IC50 of 33.4 M and 25.0 M, respectively, while polymatin B was not active. Interestingly, when the three compounds were tested against the intracellular forms of T. cruzi they were able to inhibit amastigote replication with IC50 of 5.17 M, 3.34 M and 9.02 M for 1, 2 and 3 respectively. The cytotoxicity of the compounds was evaluated in Vero cells with CC50 of 46.5 M (1), 46.8 M (2) and 147.3 M (3) and compared along with the activity against amastigote forms. According to the results obtained enhydrin and uvedalin may be potential agents for Chagas therapy and could serve as templates for developing new drugs.