Phytomedicine 22 (2015) 969–974 Contents lists available at ScienceDirect Phytomedicine journal homepage: www.elsevier.com/locate/phymed In vitro and in vivo antiparasitic activity of Physalis angulata L. concentrated ethanolic extract against Trypanosoma cruzi Cássio Santana Meira a , Elisalva Teixeira Guimarães a,b , Jamyle Andrade Ferreira dos Santos a,b , Diogo Rodrigo Magalhães Moreira a , Renata Campos Nogueira a , Therezinha Coelho Barbosa Tomassini c , Ivone Maria Ribeiro c , Claudia Valeria Campos de Souza c , Ricardo Ribeiro dos Santos d , Milena Botelho Pereira Soares a,d,∗ a Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil b Universidade do Estado da Bahia, Salvador, Bahia, Brazil c Laboratório de Química de Produtos Naturais-PN2-Extração, Isolamento e Purificação, Farmanguinhos-Fiocruz, Rio de Janeiro, RJ, Brazil d Centro de Biotecnologia e Terapia Celular, Hospital São Rafael, Salvador, BA, Brazil article info Article history: Received 23 March 2015 Revised 3 July 2015 Accepted 6 July 2015 Keywords: Chagas disease Trypanosoma cruzi Physalis angulata Plant extract Drug combination abstract Background: The current treatment of Chagas disease, endemic in Latin America and emerging in several countries, is limited by the frequent side effects and variable efficacy of benznidazole. Natural products are an important source for the search for new drugs. Aim/hypothesis: Considering the great potential of natural products as antiparasitic agents, we investigated the anti-Trypanosoma cruzi activity of a concentrated ethanolic extract of Physalis angulata (EEPA). Methods: Cytotoxicity to mammalian cells was determined using mouse peritoneal macrophages. The an- tiparasitic activity was evaluated against axenic epimastigote and bloodstream trypomastigote forms of T. cruzi, and against amastigote forms using T. cruzi-infected macrophages. Cell death mechanism was de- termined in trypomastigotes by flow cytometry analysis after annexin V and propidium iodide staining. The efficacy of EEPA was examined in vivo in an acute model of infection by monitoring blood parasitaemia and survival rate 30 days after treatment. The effect against trypomastigotes of EEPA and benznidazole acting in combination was evaluated. Results: EEPA effectively inhibits the epimastigote growth (IC 50 2.9 ± 0.1 μM) and reduces bloodstream try- pomastigote viability (EC 50 1.7 ± 0.5 μM). It causes parasite cell death by necrosis. EEPA impairs parasite infectivity as well as amastigote development in concentrations noncytotoxic to mammalian cells. In mice acutely-infected with T. cruzi, EEPA reduced the blood parasitaemia in 72.7%. When combined with benznida- zole, EEPA showed a synergistic anti-T. cruzi activity, displaying CI values of 0.8 ± 0.07 at EC 50 and 0.83 ± 0.1 at EC 90 . Conclusion: EEPA has antiparasitic activity against T. cruzi, causing cell death by necrosis and showing syner- gistic activity with benznidazole. These findings were reinforced by the observed efficacy of EEPA in reducing parasite load in T. cruzi-mice. Therefore, this represents an important source of antiparasitic natural products. © 2015 Elsevier GmbH. All rights reserved. Abbreviations: EEPA, ethanolic extract from P. angulata; DMSO, dimethyl sulfoxide; DTU, discrete typing unit; LIT, liver infusion tryptose; FBS, fetal bovine serum; RPMI, Roswell park memorial institute; PI, propidium iodide; CC 50 , cytotoxicity concentra- tion of 50%; IC 50 , inhibitory concentration of 50%; EC 50 , effective concentration at 50%; ANOVA, analysis of variance; EC 90 , effective concentration of 90%; CI, combination in- dex; GV, gentian violet; BDZ, benznidazole; SEM, standard error of the mean; SD, stan- dard deviation; DPI, days post-infection. ∗ Corresponding author at: Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz. 121, Rua Waldemar Falcão, Candeal, Salvador 40296-710, Bahia, Brazil. Tel.: +55 71 3176 2260; fax: +55 71 3176 2272. E-mail address: milenabpsoares@gmail.com, milena@bahia.fiocruz.br (M.B.P. Soares). Introduction Chagas disease, a zoonosis caused by the hemoflagellate proto- zoan Trypanosoma cruzi, remains a serious health problem in many Latin American countries, where it is an endemic disease that affects approximately 10 million people (Rassi et al. 2010). It is estimated that over 400.000 individuals are infected in non-endemic areas, mainly in the USA and in European countries (Coura and Viñas 2010). Once the individual has been infected by T. cruzi, there is no effective treatment and the development of a vaccine is still in experimental stage (Gupta et al. 2013; Maya et al. 2007). The current treatment is based on the 2-nitroimidazole benznidazole (LAFEPE, Brazil), which http://dx.doi.org/10.1016/j.phymed.2015.07.004 0944-7113/© 2015 Elsevier GmbH. All rights reserved.