Veterinary Parasitology 186 (2012) 261–269 Contents lists available at SciVerse ScienceDirect Veterinary Parasitology jo u rn al hom epa ge : www.elsevier.com/locate/vetpar A new type of pterocarpanquinone that affects Toxoplasma gondii tachyzoites in vitro Juliana de Araujo Portes a , Chaquip Daher Netto b , Alcides José Monteiro da Silva c , Paulo Roberto Ribeiro Costa c , Renato Augusto DaMatta d , Thiago Alves Teixeira dos Santos a , Wanderley De Souza e , Sergio Henrique Seabra a,∗ a Laboratório de Tecnologia em Cultura de Células, Centro Universitário Estadual da Zona Oeste (UEZO) – Av. Manuel Caldeira de Alvarenga, 1203, Campo Grande, Rio de Janeiro, RJ, CEP: 23070-200, Brazil b Laboratório Integrado Multiusuário II, Instituto Macaé de Metrologia e Tecnologia, Universidade Federal do Rio de Janeiro, Campus Macaé, Brazil c Laboratório de Química Bioorgânica, Núcleo de Pesquisas de Produtos Naturais, Centro de Ciências da Saúde, Bloco H, Universidade Federal do Rio de Janeiro, RJ, CEP: 21941-590, Brazil d Laboratório de Biologia Celular e Tecidual, Centro de Biociências e Biotecnologia, Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ, Brazil e Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil a r t i c l e i n f o Article history: Received 5 May 2011 Received in revised form 5 September 2011 Accepted 1 November 2011 Keywords: Chemotherapy Toxoplasma gondii Ultrastructure New pterocarpanquinone derivative Anti-proliferative activity a b s t r a c t Toxoplasma gondii, the agent of Toxoplasmosis, is an obligate intracellular protozoan able to infect a wide range of vertebrate cells, including nonprofessional and professional phago- cytes. Therefore, drugs must have intracellular activities in order to control this parasite. The most common therapy for Toxoplasmosis is the combination of sulfadiazine and pyrimethamine. This treatment is associated with adverse reactions, thus, the develop- ment of new drugs is necessary. In previous studies, naphthoquinone derivatives showed anti-cancer activity functioning as agents capable of acting on groups of DNA, preventing cancer cells duplication. These derivatives also display anti-parasitic activity against Plas- modium falciparum and Leishmania amazonensis. The derivative pterocarpanquinone tested in this work resulted from the molecular hybridization between pterocarpans and naphto- quinone that presents anti-tumoral and anti-parasitic activities of lapachol. The aim of this work was to determine if this derivative is able to change T. gondii growth within LLC-MK2 cells. The drug did not arrest host cell growth, but was able to decrease the infection index of T. gondii with an IC 50 of 2.5 M. Scanning and transmission electron microscopy analy- sis showed morphological changes of parasites including membrane damage. The parasite that survived tended to encyst as seen by Dolichos biflorus lectin staining and Bag-1 expres- sion. These results suggest that pterocarpanquinones are drugs potentially important for the killing and encystment of T. gondii. © 2011 Elsevier B.V. All rights reserved. ∗ Corresponding author. Tel.: +55 21 2332 7535; fax: +55 21 2332 7535. E-mail addresses: julianaportes@yahoo.com.br (J.d.A. Portes), alcides@nppn.ufrj.br (A.J.M. da Silva), prrcosta@ism.com.br (P.R.R. Costa), renato@uenf.br (R.A. DaMatta), wsouza@biof.ufrj.br (W. De Souza), seabra@pq.cnpq.br (S.H. Seabra). 1. Introduction Toxoplasma gondii is an intracellular parasitic proto- zoan with worldwide distribution in warm blood animals, including humans, which causes toxoplasmosis (Levine et al., 1980; Lyons and Johnson, 1995). In immunocompe- tent organisms the infection by T. gondii is rarely severe, 0304-4017/$ – see front matter © 2011 Elsevier B.V. All rights reserved. doi:10.1016/j.vetpar.2011.11.008