Synergistic effect and ultrastructural changes in Trypanosoma cruzicaused by isoobtusilactone A in short exposure of time.

Júlio Menta De Almeida,Inês Aparecida Tozetti,Lia Carolina Soares Medeiros,Felipe Oliveira Nunes,Tabata D’Maiella Freitas Klimeck,Fernanda Rodrigues Garcez,Alda Maria Teixeira Ferreira,Beatriz Santana Borges,Lígia Fernanda Ceole,Letícia Alves Da Cruz,Danilo Tófoli,Walmir Silva Garcez,Muhammad Aamer Mehmood

doi:10.1371/journal.pone.0245882

Júlio Menta De Almeida, Inês Aparecida Tozetti + Show 11 more

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https://doi.org/10.1371/journal.pone.0245882

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Abstract

Butanolides have shown a variety of biological effects including anti-inflammatory, antibacterial, and antiprotozoal effects against certain strains of Trypanosoma cruzi. Considering the lack of an effective drug to treat T. cruzi infections and the prominent results obtained in literature with this class of lactones, we investigated the anti-T. cruzi activity of five butanolides isolated from two species of Lauraceae, Aiouea trinervis and Mezilaurus crassiramea. Initially, the activity of these compounds was evaluated on epimastigote forms of the parasite, after a treatment period of 4 h, followed by testing on amastigotes, trypomastigotes, and mammalian cells. Next, the synergistic effect of active butanolides against amastigotes was evaluated. Further, metacyclogenesis inhibition and infectivity assays were performed for the most active compound, followed by ultrastructural analysis of the treated amastigotes and trypomastigotes. Among the five butanolides studied, majoranolide and isoobtusilactone A were active against all forms of the parasite, with good selectivity indexes in Vero cells. Both butanolides were more active than the control drug against trypomastigote and epimastigote forms and also had a synergic effect on amastigotes. The most active compound, isoobtusilactone A, which showed activity against all tested strains inhibited metacyclogenesis and infection of new host cells. In addition, ultrastructural analysis revealed that this butanolide caused extensive damage to the mitochondria of both amastigotes and trypomastigotes, resulting in severe morphological changes in the infective forms of the parasite. Altogether, our results highlight the potential of butanolides against the etiologic agent of Chagas disease and the relevance of isoobtusilactone A as a strong anti-T. cruzi drug, affecting different events of the life cycle and all evolutionary forms of parasite after a short period of exposure.

Highlights

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is still a major public health concern worldwide, and is associated with many secondary diseases, disability, early retirement, and extensive treatment costs [1].Considering the lack of an appropriate drug for treatment of T. cruzi infection during the chronic phase of the disease, the development of a new and more effective anti-T. cruzi drug could mitigate the economic, social, and health problems related to this disease [2].Worsening this scenario, oral infection has exceeded the classic transmission, and has become the foremost common infection in recent years in Brazil
Considering that few studies have reported the antitrypanosomal potential of this class of secondary metabolites, we evaluated the activity of five butanolides previously isolated by our group [10,11,12] from two lauraceous species, namely, Aiouea trinervis and Mezilaurus crassiramea (Lauraceae), against epimastigote forms of different strains as well as other evolutive forms of T. cruzi, after a treatment period of 4 h
We evaluated the synergistic effect of active butanolides and studied the capacity of the most active butanolide to inhibit important mechanisms in the parasite’s life cycle in both vertebrate and invertebrate hosts, emphasizing the ultrastructural study of the parasitic forms found in the vertebrate and the process of host cell infection

Summary

Introduction

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is still a major public health concern worldwide, and is associated with many secondary diseases, disability, early retirement, and extensive treatment costs [1]. Considering the lack of an appropriate drug for treatment of T. cruzi infection during the chronic phase of the disease, the development of a new and more effective anti-T. cruzi drug could mitigate the economic, social, and health problems related to this disease [2] Worsening this scenario, oral infection has exceeded the classic transmission, and has become the foremost common infection in recent years in Brazil. Considering that few studies have reported the antitrypanosomal potential of this class of secondary metabolites, we evaluated the activity of five butanolides previously isolated by our group [10,11,12] from two lauraceous species, namely, Aiouea trinervis and Mezilaurus crassiramea (Lauraceae), against epimastigote forms of different strains as well as other evolutive forms of T. cruzi, after a treatment period of 4 h. We evaluated the synergistic effect of active butanolides and studied the capacity of the most active butanolide to inhibit important mechanisms in the parasite’s life cycle in both vertebrate and invertebrate hosts, emphasizing the ultrastructural study of the parasitic forms found in the vertebrate and the process of host cell infection

Materials and methods

Findings

Discussion