Chagas disease is a severe infectious and parasitic disease caused by the protozoan Trypanosoma cruzi and considered a public health problem. Chemotherapeutics are still the main means of control and treatment of the disease, however with some limitations. As an alternative treatment, plants have been pointed out due to their proven pharmacological properties. Many studies carried out with Terminalia catappa have shown several biological activities, but its effect against T. cruzi is still unknown. The objective of this work is to evaluate the therapeutic potential of extracts and fractions obtained from T. catappa on the parasite T. cruzi, in addition to analyzing its antioxidant activity. T. catappa ethyl acetate fraction were produced and submitted the chemical characterization by Liquid Chromatography Coupled to Mass Spectrometry (LC-MS). From all T. catappa extracts and fractions evaluated, the ethyl acetate and the aqueous fraction displayed the best antioxidant activity by the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging method (IC50 of 7.77 ± 1.61 and 5.26 ± 1.26 µg/mL respectively), and by ferric ion reducing (FRAP) method (687.61 ± 0.26 and 1009.32 ± 0.13 µM of Trolox equivalent/mg extract, respectively). The ethyl acetate fraction showed remarkable T. cruzi inhibitory activity with IC50 of 8.86 ± 1.13, 24.91 ± 1.15 and 85.01 ± 1.21 µg/mL against epimastigotes, trypomastigotes and intracellular amastigotes, respectively, and showed no cytotoxicity for Vero cells (CC50 > 1000 µg/mL). The treatment of epimastigotes with the ethyl acetate fraction led to drastic ultrastructural changes such as the loss of cytoplasm organelles, cell disorganization, nucleus damage and the loss of integrity of the parasite. This effect could be due to secondary compounds present in this extract, such as luteolin, kaempferol, quercetin, ellagic acid and derivatives. The ethyl acetate fraction obtained from T. catappa leaves can be an effective alternative in the treatment and control of Chagas disease, and material for further investigations.
Keywords: Trypanosoma cruzi; alternative treatment; chagas disease; combretaceae; ellagic acid; parasite.