AÇÃO DE FÁRMACOS SELECIONADOS IN SILICO SOBRE ALVOS FUNCIONAIS EM FORMAS EPIMASTIGOTAS DE​ Trypanosoma cruzi

Abstract

Chagas disease (CD) is an infection caused by the protozoan Trypanosoma cruzi, which is transmitted predominantly through contact with the waste of insect vectors known as "barbers". Although this disease represents a major challenge for public health, currently in Brazil there is only one drug for treating the disease, benznidazole, which has low efficacy in the chronic phase and severe adverse effects. The search for new drugs that can act more safely and efficiently throughout the infection is therefore justified. To this end, this study investigated potential functional targets such as replication, plasma membrane integrity, cell cycle, mitochondrial membrane potential, complexity and cell size of T. cruzi epimastigotes treated with the 50% Inhibitory Concentration (IC50) of the previously selected drugs in silico, oxiconazole nitrate and lansoprazole. This is an experimental study, carried out with in vitro assays, using a clonal population of Trypanosoma cruzi strain Dm28c, maintained under periodic repiques in Liver Infusion Tryptose (LIT) medium. The epimastigote form of the parasite was used for the experiments, which were subjected to treatment with different concentrations of drugs for 24 hours to determine the IC50/24h. For the flow cytometry tests, the parasites were treated with the IC50 of each drug for 24 hours. The effect of the drugs (IC50) on parasite replication was also assessed over 120 hours. Microsoft Excel 2020 and GraphPadPrism 7.04 were used to analyze the treatment time and drug variables; and FACSDIVA and FlowJo were used to analyze the cytometry data. As for the statistical analysis, the experiments were carried out in triplicate and the differences between the percentage of parasite viability were compared between the times and for each drug using analysis of variance (ANOVA) with Tukey's post-test. p-values equal to or less than 0.05 were considered significant. Among the findings of this study, it was observed that oxiconazole nitrate affected the replication of the parasite, in addition to its ability to permeabilize the cytoplasmic membrane and interfere with its cell cycle; lansoprazole in turn showed similar results to the untreated control. Therefore, oxiconazole nitrate is a promising candidate as an active drug against T. cruzi. Further analysis is suggested to better understand the possible mechanism of action of lansoprazole on the microorganism.