In vitro and in vivo antimalarial activity of the volatile oil of Cyperus articulatus (Cyperaceae)

ABSTRACT Malaria is a disease of global tropical distribution, being endemic in more than 90 countries and responsible for about 212 million cases worldwide in 2016. To date, the strategies used to eradicate this disease have been ineffective, without specific preventive measures such as vaccines. Currently, the existing therapeutic arsenal is limited and has become ineffective against the expansion of artemisinin-resistant Plasmodium, demonstrating the need for studies that would allow the development of new compounds against this disease. In this context, we studied the volatile oil obtained from rhizomes of Cyperus articulatus (VOCA), a plant species commonly found in the Amazon region and popularly used as a therapeutic alternative for the treatment of malaria, in order to confirm its potential as an antimalarial agent by in vitro and in vivo assays. We cultured Plasmodium falciparum W2 (chloroquine-resistant) and 3D7 (chloroquine-sensitive) strains in erythrocytes and exposed them to VOCA at different concentrations in 96-well microplates. In vivo antimalarial activity was tested in BALB/c mice inoculated with approximately 106 erythrocytes infected with Plasmodium berghei. VOCA showed a high antimalarial potential against the two P. falciparum strains, with IC50 = 1.21 μg mL-1 for W2 and 2.30 μg mL-1 for 3D7. VOCA also significantly reduced the parasitemia and anemia induced by P. berghei in mice. Our results confirmed the antimalarial potential of the volatile oil of Cyperus articulatus. RESUMO A malária é uma doença de distribuição tropical, sendo endêmica em mais de 90 países, responsável por cerca de 212 milhões de casos reportados ao redor do mundo em 2016. As estratégias de erradicação dessa doença são ineficazes até o presente, sem medidas de prevenção específica, como vacinas. Atualmente, o arsenal terapêutico existente é limitado e vem se tornando ineficaz frente à expansão de plasmódios resistentes a artemisinina, evidenciando a necessidade de estudos que viabilizem o desenvolvimento de novos compostos contra a doença. Nesse contexto, estudamos o óleo essencial obtido de rizomas de Cyperus articulatus (VOCA), uma espécie vegetal comumente encontrada na região amazônica, utilizada popularmente como alternativa terapêutica para o tratamento de malária. Visamos confirmar o potencial antimalárico da planta através de testes in vitro e in vivo. Utilizamos cepas de Plasmodium falciparum W2 (cloroquina-resistente) e 3D7 (cloroquina-sensível) culti