Extrato etanólico das folhas e oleorresina de Copaifera multijuga controlam a infecção por Toxoplasma gondii em células trofoblásticas humanas vilosas (BeWo), extravilosas (HTR8/SVneo) e em vilos coriônicos humanos de terceiro trimestre gestacional

Abstract

Conventional treatment of congenital toxoplasmosis has few effective options, but the most used are drugs based mainly on the combination of sulfadiazine and pyrimethamine. However, therapy with these drugs is associated with severe side effects and resistance, requiring the study of new therapeutic strategies. Currently, there are many studies with natural products, including Copaifera oil, showing action against some pathogens such as Trypanosoma cruzi and Leishmania. In the present study, we investigated the effects of ethanol extract from leaves and oleoresin of Copaifera multijuga against Toxoplasma gondii in human villous (BeWo) and extravillous (HTR8/SVneo) trophoblastic cells, as well as in third trimester human villous explants. For this purpose, both cells and villous explants were infected or not with T. gondii, treated with ethanol extract or oleoresin from C. multijuga and analyzed for cellular toxicity, parasite proliferation, cytokine and ROS production. In parallel, both cells were infected by tachyzoites pre-treated with ethanol extract or oleoresin, and adhesion, invasion and parasite replication were observed. Our results showed that the extract and oleoresin did not trigger toxicity at low concentrations and were able to reduce intracellular proliferation of T. gondii in previously infected cells. In addition, ethanol extract and oleoresin demonstrated irreversible antiparasitic action on BeWo and HTR8/SVneo cells. Then, T. gondii adhesion, invasion and replication were attenuated when BeWo or HTR8/SVneo cells were infected with pre-treated tachyzoites. Finally, infected and treated BeWo cells up-regulated IL-6 and down-modulated IL-8, while HTR8/SVneo cells did not significantly alter these cytokines when infected by the parasite. Finally, the ethanol extract and oleoresin reduced the proliferation of T. gondii in human villi explants, and this effect is probably a direct mechanism of action on the parasites. Thus, compounds from C. multijuga showed different antiparasitic activities in a trophoblastic population-dependent manner, with the direct action on tachyzoites being a common mechanism operating in both cells. Considering all these parameters, the ethanolic extract and the oleoresin from C. multijuga can be targets for the establishment of a new therapeutic strategy for congenital toxoplasmosis.