RESUMO
OBJECTIVE: This study aimed to investigate the potential antitoxoplasma activities of extracts of the endemic plants Centaurea lydia and Phlomis nissolii in a fibroblast cell culture infected with T. gondii trophozoites. METHODS: WI-38 cell lines treated with plant extracts (55 µg/mL each) and an untreated control were infected with 5×105 T. gondii trophozoites, and the number of parasites in the medium was determined on days 7, 14, and 24. RESULTS: No cytotoxic effects of C. lydia and P. nissolii extracts were detected at concentrations of 0.86-55 µg/mL in the WI-38 cell line, and the absence of the cytotoxicity of these extracts on the fibroblast cell line was considered as a positive effect. C. lydia extract at 55 µg/mL had marked activity against T. gondii trophozoites. A 47.5-fold increase was observed in the number of trophozoites in the control group, while a 84-fold decrease was found in the C. lydia extract group. However, a 36-fold increase was detected in the P. nissolii extract group, indicating no antitoxoplasma activity. CONCLUSION: The extract of C. lydia, an endemic plant, was found to be a good drug candidate for treating toxoplasmosis. The in vitro activity of the extract of this endemic plant should be further investigated in animal models in vivo.
