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Lucas da Silva HF, Sarto MPM, de Abreu AP, Fernandes NDS, Santos IGMD, de Souza Trovo JV, da Silva AF, Souza-Kaneshima AM, Comar JF, Toledo MJDO. Impact of gastrointestinal inoculation and benznidazole treatment on infection by Trypanosoma cruzi (Y strain, DTU TcII) in Swiss mice. Exp Parasitol 2024; 265:108810. [PMID: 39134115 DOI: 10.1016/j.exppara.2024.108810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/08/2024] [Accepted: 08/05/2024] [Indexed: 08/23/2024]
Abstract
In Brazil, where Chagas disease is endemic, the most frequent form of transmission of the parasite is the oral route, associated with greater severity and worse response to benznidazole (BZ), the drug used in its treatment. This study aimed to evaluate the impact of gastrointestinal infection (GI) and BZ treatment on the parasitological and histopathological parameters in mice inoculated with a strain of T. cruzi II. Swiss mice were inoculated by GI and intraperitoneal (IP) routes with 2x106 culture-derived metacyclic trypomastigotes of the Y strain (TcII) of T. cruzi and were treated with BZ in the acute phase of the infection. Fresh blood examination, qPCR, histopathological and biochemical evaluations (enzymatic dosages and oxidative stress-OS) were performed. BZ treatment of uninfected animals caused changes in the liver, increased the activity of aspartate aminotransferase and alanine aminotransferase enzymes and OS, showing that the drug alone affects this organ. Inflammation and necrosis in the cardiac tissue were less intense and deaths occurred later in animals inoculated via the GI route than the animals inoculated via the IP route. BZ reduced the intensity of tissue lesions and avoided lethality in animals inoculated via the GI route, and decreased parasitemia and OS in those inoculated via both routes. Although BZ alone caused liver damage, it was less intense than that caused by both routes of inoculation. Infection with the Y strain of T. cruzi II via the GI route proved to be less virulent and pathogenic and responded better to treatment than the infection acquired via the IP route.
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Affiliation(s)
| | - Marcella Paula Mansano Sarto
- Postgraduate Program in Health Sciences, Health Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | - Ana Paula de Abreu
- Postgraduate Program in Health Sciences, Health Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | - Nilma de Souza Fernandes
- Postgraduate Program in Biological Sciences, Biological Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | | | - João Vitor de Souza Trovo
- Postgraduate Program in Health Sciences, Health Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | - Aline Francieli da Silva
- Postgraduate Program in Biological Sciences, Biological Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | - Alice Maria Souza-Kaneshima
- Department of Basic Health Sciences, Health Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | - Jurandir Fernando Comar
- Postgraduate Program in Biological Sciences, Biological Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
| | - Max Jean de Ornelas Toledo
- Postgraduate Program in Health Sciences, Health Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil; Postgraduate Program in Biological Sciences, Biological Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil; Department of Basic Health Sciences, Health Sciences Center, State University of Maringá, Maringá, 87.020.900, Brazil.
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Mazzeti AL, Gonçalves KR, Boasquívis PF, Barbosa J, Pereira BG, Soeiro MDNC, Mosqueira VCF, Bahia MT. Poly-ε-Caprolactone Implants for Benznidazole Prolonged Release: An Alternative to Chagas Disease Oral Treatment. Pharmaceutics 2023; 15:pharmaceutics15041126. [PMID: 37111612 PMCID: PMC10147077 DOI: 10.3390/pharmaceutics15041126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 03/20/2023] [Accepted: 03/24/2023] [Indexed: 04/05/2023] Open
Abstract
Benznidazole (BZ) tablets are the currently prescribed treatment for Chagas disease. However, BZ presents limited efficacy and a prolonged treatment regimen with dose-dependent side effects. The design and development of new BZ subcutaneous (SC) implants based on the biodegradable poly-ɛ-caprolactone (PCL) is proposed in this study for a controlled release of BZ and to improve patient compliance. The BZ–PCL implants were characterized by X-ray diffraction, differential scanning calorimetry, and scanning electron microscopy, which indicated that BZ remains in its crystalline state dispersed in the polymer matrix with no polymorphic transitions. BZ–PCL implants, even at the highest doses, induce no alteration of the levels of hepatic enzymes in treated animals. BZ release from implants to blood was monitored in plasma during and after treatment in healthy and infected animals. Implants at equivalent oral doses increase the body’s exposure to BZ in the first days compared with oral therapy, exhibiting a safe profile and allowing sustained BZ concentrations in plasma to induce a cure of all mice in the experimental model of acute infection by the Y strain of T. cruzi. BZ–PCL implants have the same efficacy as 40 daily oral doses of BZ. Biodegradable BZ implants are a promising option to reduce failures related to poor adherence to treatment, with more comfort for patients, and with sustained BZ plasma concentration in the blood. These results are relevant for optimizing human Chagas disease treatment regimens.
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Affiliation(s)
- Ana Lia Mazzeti
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro 21040-360, RJ, Brazil
- Laboratório de Parasitologia Básica e Aplicada, Universidade do Estado de Minas Gerais, Unidade Acadêmica de Passos, Passos 37900-106, MG, Brazil
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto 35400-000, MG, Brazil
| | - Karolina R. Gonçalves
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto 35400-000, MG, Brazil
| | | | - Jamile Barbosa
- Diretoria Industrial, Fundação Ezequiel Dias, Belo Horizonte 30510-010, MG, Brazil
| | - Bruno G. Pereira
- Diretoria Industrial, Fundação Ezequiel Dias, Belo Horizonte 30510-010, MG, Brazil
| | | | - Vanessa Carla Furtado Mosqueira
- Laboratory of Pharmaceutics and Nanotechnology (LDGNano), School of Pharmacy, Federal University of Ouro Preto, Ouro Preto 35400-000, MG, Brazil
| | - Maria Terezinha Bahia
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto 35400-000, MG, Brazil
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San Francisco J, Astudillo C, Vega JL, Catalán A, Gutiérrez B, Araya JE, Zailberger A, Marina A, García C, Sanchez N, Osuna A, Vilchez S, Ramírez MI, Macedo J, Feijoli VS, Palmisano G, González J. Trypanosoma cruzi pathogenicity involves virulence factor expression and upregulation of bioenergetic and biosynthetic pathways. Virulence 2022; 13:1827-1848. [PMID: 36284085 PMCID: PMC9601562 DOI: 10.1080/21505594.2022.2132776] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
The molecular repertoire of Trypanosoma cruzi effects its virulence and impacts the clinical course of the resulting Chagas disease. This study aimed to determine the mechanism underlying the pathogenicity of T. cruzi. Two T. cruzi cell lines (C8C3hvir and C8C3lvir), obtained from the clone H510 C8C3 and exhibiting different virulence phenotypes, were used to evaluate the parasite's infectivity in mice. The organ parasite load was analysed by qPCR. The proteomes of both T. cruzi cell lines were compared using nLC-MS/MS. Cruzipain (Czp), complement regulatory protein (CRP), trans-sialidase (TS), Tc-85, and sialylated epitope expression levels were evaluated by immunoblotting. High-virulence C8C3hvir was highly infectious in mice and demonstrated three to five times higher infectivity in mouse myocardial cells than low-virulence C8C3lvir. qPCR revealed higher parasite loads in organs of acute as well as chronically C8C3hvir-infected mice than in those of C8C3lvir-infected mice. Comparative quantitative proteomics revealed that 390 of 1547 identified proteins were differentially regulated in C8C3hvir with respect to C8C3lvir. Amongst these, 174 proteins were upregulated in C8C3hvir and 216 were downregulated in C8C3lvir. The upregulated proteins in C8C3hvir were associated with the tricarboxylic acid cycle, ribosomal proteins, and redoxins. Higher levels of Czp, CRP, TS, Tc-85, and sialylated epitopes were expressed in C8C3hvir than in C8C3lvir. Thus, T. cruzi virulence may be related to virulence factor expression as well as upregulation of bioenergetic and biosynthetic pathways proteins.
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Affiliation(s)
- Juan San Francisco
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile
| | - Constanza Astudillo
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile
| | - José Luis Vega
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile,Laboratory of Gap Junction Proteins and Parasitic Disease, Instituto Antofagasta, Universidad de Antofagasta, Antofagasta, Chile,Research Center in Immunology and Biomedical Biotechnology of Antofagasta, Antofagasta, Chile
| | - Alejandro Catalán
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile
| | - Bessy Gutiérrez
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile
| | - Jorge E Araya
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile
| | | | - Anabel Marina
- Centro de Biología Molecular Severo Ochoa Universidad Autonoma de Madrid, Madrid, Spain
| | - Carlos García
- Centro de Biología Molecular Severo Ochoa Universidad Autonoma de Madrid, Madrid, Spain
| | - Nuria Sanchez
- Centro de Biología Molecular Severo Ochoa Universidad Autonoma de Madrid, Madrid, Spain
| | - Antonio Osuna
- Institute of Biotechnology, University of Granada, Granada, Spain
| | - Susana Vilchez
- Institute of Biotechnology, University of Granada, Granada, Spain
| | - Marcel I Ramírez
- Laboratório de Biologia Molecular e Sistemática de Trypanosomatides, Instituto Carlos Chagas, Fiocruz, Parana, Brazil
| | - Janaina Macedo
- Department of Parasitology, University of Sao Paulo, Sao Paulo, Brazil
| | | | | | - Jorge González
- Molecular Parasitology Unit, Medical Technology Department, University of Antofagasta, Antofagasta, Chile,Research Center in Immunology and Biomedical Biotechnology of Antofagasta, Antofagasta, Chile,Laboratório de Biologia Molecular e Sistemática de Trypanosomatides, Millennium Institute on Immunology and Immunotherapy, Antofagasta, Chile,CONTACT Jorge González
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Martín-Escolano R, Rosales MJ, Marín C. Biological characteristics of the Trypanosoma cruzi Arequipa strain make it a good model for Chagas disease drug discovery. Acta Trop 2022; 236:106679. [PMID: 36096184 DOI: 10.1016/j.actatropica.2022.106679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 09/04/2022] [Accepted: 09/05/2022] [Indexed: 11/18/2022]
Abstract
Trypanosoma cruzi, the causative agent of Chagas disease (CD), is a genuine parasite with tremendous genetic diversity and a complex life cycle. Scientists have studied this disease for more than 100 years, and CD drug discovery has been a mainstay due to the absence of an effective treatment. Technical advances in several areas have contributed to a better understanding of the complex biology and life cycle of this parasite, with the aim of designing the ideal profile of both drug and therapeutic options to treat CD. Here, we present the T. cruzi Arequipa strain (MHOM/Pe/2011/Arequipa) as an interesting model for CD drug discovery. We characterized acute-phase parasitaemia and chronic-phase tropism in BALB/c mice and determined the in vitro and in vivo benznidazole susceptibility profile of the different morphological forms of this strain. The tropism of this strain makes it an interesting model for the screening of new compounds with a potential anti-Chagas profile for the treatment of this disease.
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Affiliation(s)
- Rubén Martín-Escolano
- Laboratory of Molecular & Evolutionary Parasitology, RAPID Group, School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK.
| | - María José Rosales
- Department of Parasitology, University of Granada, Severo Ochoa s/n, Granada 18071, Spain
| | - Clotilde Marín
- Department of Parasitology, University of Granada, Severo Ochoa s/n, Granada 18071, Spain.
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Mazzeti AL, Gonçalves KR, Mota SLA, Pereira DE, Diniz LDF, Bahia MT. Combination therapy using nitro compounds improves the efficacy of experimental Chagas disease treatment. Parasitology 2021; 148:1320-1327. [PMID: 34247670 PMCID: PMC11010181 DOI: 10.1017/s0031182021001001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 06/15/2021] [Indexed: 11/08/2022]
Abstract
Drug combinations have been evaluated for Chagas disease in an attempt to improve efficacy and safety. In this line, the objective of this work is to assess the effects of treatment with nitro drugs combinations using benznidazole (BZ) or nifurtimox (NFX) plus the sulfone metabolite of fexinidazole (fex-SFN) in vitro and in vivo on Trypanosoma cruzi infection. The in vitro interaction of fex-SFN and BZ or NFX against infected H9c2 cells by the Y strain was classified as an additive (0.5⩾ΣFIC<4), suggesting the possibility of a dose reduction in the in vivo T. cruzi infection. Next, the effect of combining suboptimal doses was assessed in an acute model of murine T. cruzi infection. Drug combinations led to a faster suppression of parasitemia than monotherapies. Also, the associations led to higher cure levels than those in the reference treatment BZ 100 mg day−1 (57.1%) (i.e. 83.3% with BZ/fex-SFN and 75% with NFX/fex-SFN). Importantly, toxic effects resulting from the associations were not observed, according to weight gain and hepatic enzyme levels in the serum of experimental animals. Taken together, this study is a starting point to explore the potential effects of nitro drugs combinations in preclinical models of kinetoplastid-related infections.
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Affiliation(s)
- Ana Lia Mazzeti
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG35400-000, Brazil
- Laboratório de Biologia Celular, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ21040-360, Brazil
| | - Karolina R. Gonçalves
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG35400-000, Brazil
| | - Suianne L. A. Mota
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG35400-000, Brazil
| | - Dário Elias Pereira
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG35400-000, Brazil
| | - Lívia de F. Diniz
- Laboratório de Parasitologia Básica, Departamento de Patologia e Parasitologia, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Alfenas, MG37130-001, Brazil
| | - Maria Terezinha Bahia
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário Morro do Cruzeiro, Ouro Preto, MG35400-000, Brazil
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6
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Higher oral efficacy of ravuconazole in self-nanoemulsifying systems in shorter treatment in experimental chagas disease. Exp Parasitol 2021; 228:108142. [PMID: 34375652 DOI: 10.1016/j.exppara.2021.108142] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 06/24/2021] [Accepted: 08/06/2021] [Indexed: 11/23/2022]
Abstract
We investigated the in vitro activity and selectivity, and in vivo efficacy of ravuconazole (RAV) in self-nanoemulsifying delivery system (SNEDDS) against Trypanosoma cruzi. Novel formulations of this poorly soluble C14-α-demethylase inhibitor may improve its efficacy in the experimental treatment. In vitro activity was determined in infected cardiomyocytes and efficacy in vivo evaluated in terms of parasitological cure induced in Y and Colombian strains of T. cruzi-infected mice. In vitro RAV-SNEDDS exhibited significantly higher potency of 1.9-fold at the IC50 level and 2-fold at IC90 level than free-RAV. No difference in activity with Colombian strain was observed in vitro. Oral treatment with a daily dose of 20 mg/kg for 30 days resulted in 70% of cure for RAV-SNEDDS versus 40% for free-RAV and 50% for 100 mg/kg benznidazole in acute infection (T. cruzi Y strain). Long-term treatment efficacy (40 days) was able to cure 100% of Y strain-infected animals with both RAV preparations. Longer treatment time was also efficient to increase the cure rate with benznidazole (Y and Colombian strains). RAV-SNEDDS shows greater efficacy in a shorter time treatment regimen, it is safe and could be a promising formulation to be evaluated in other pre-clinical models to treat T. cruzi and fungi infections.
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Nielebock MAP, de Freitas Campos Miranda L, Americano do Brasil PEA, de Jesus S Pereira TO, da Silva AF, Hasslocher-Moreno AM, Sangenis LHC, Saraiva RM. Blood culture positivity rate for Trypanosoma cruzi in patients with chronic Chagas disease differs among different clinical forms. Trans R Soc Trop Med Hyg 2021; 115:720-725. [PMID: 33150435 DOI: 10.1093/trstmh/traa121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 09/04/2020] [Accepted: 10/18/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The purpose of this research was to compare the clinical and epidemiological characteristics of patients with chronic Chagas disease with and without positive blood cultures for Trypanosoma cruzi. METHODS This was a retrospective longitudinal study that included 139 patients with chronic Chagas disease who underwent blood culture for T. cruzi. Blood cultures were performed using Novy-MacNeal-Nicolle medium enriched with Schneider's medium. Multivariate Cox proportional hazards regression analysis adjusting for age and sex was performed to identify if positive blood culture for T. cruzi was associated with all-cause mortality. RESULTS The blood culture positivity rate was 30.9%. Most patients were born in the Northeast and Southeast regions of Brazil. Patients with positive blood cultures were older (52±13 vs 45±13 y; p=0.0009) and more frequently women (72.1% vs. 53.1%; p=0.03) than patients with negative blood cultures. The frequency of patients with cardiac or cardiodigestive forms was higher among patients with positive vs negative blood cultures (74.4% vs 54.1%; p=0.02). A total of 28 patients died during a mean follow-up time of 6.6±4.1 y. A positive blood culture was associated with all-cause mortality (hazard ratio 2.26 [95% confidence interval 1.02 to 5.01], p=0.045). CONCLUSIONS We found a higher proportion of patients with Chagas heart disease among patients with T. cruzi-positive blood cultures. A positive blood culture was associated with an increased risk of all-cause mortality. Therefore T. cruzi persistence may influence Chagas disease pathogenesis and prognosis.
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Affiliation(s)
- Marco Antonio Prates Nielebock
- Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Av. Brasil 4365, Rio de Janeiro, Brazil 21040-900
| | - Luciana de Freitas Campos Miranda
- Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Av. Brasil 4365, Rio de Janeiro, Brazil 21040-900
| | | | | | - Aline Fagundes da Silva
- Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Av. Brasil 4365, Rio de Janeiro, Brazil 21040-900
| | | | - Luiz Henrique Conde Sangenis
- Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Av. Brasil 4365, Rio de Janeiro, Brazil 21040-900
| | - Roberto Magalhães Saraiva
- Evandro Chagas National Institute of Infectious Diseases, Oswaldo Cruz Foundation, Av. Brasil 4365, Rio de Janeiro, Brazil 21040-900
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Fonseca KDS, Perin L, de Paiva NCN, da Silva BC, Duarte THC, Marques FDS, Costa GDP, Molina I, Correa-Oliveira R, Vieira PMDA, Carneiro CM. Benznidazole Treatment: Time- and Dose-Dependence Varies with the Trypanosoma cruzi Strain. Pathogens 2021; 10:729. [PMID: 34207764 PMCID: PMC8229751 DOI: 10.3390/pathogens10060729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 12/02/2022] Open
Abstract
As the development of new drugs for Chagas disease is not a priority due to its neglected disease status, an option for increasing treatment adherence is to explore alternative treatment regimens, which may decrease the incidence of side effects. Therefore, we evaluated the efficacy of different therapeutic schemes with benznidazole (BNZ) on the acute and chronic phases of the disease, using mice infected with strains that have different BNZ susceptibilities. Our results show that the groups of animals infected by VL-10 strain, when treated in the chronic phase with a lower dose of BNZ for a longer period of time (40 mg/kg/day for 40 days) presented better treatment efficacy than with the standard protocol (100 mg/kg/day for 20 days) although the best result in the treatment of the animals infected by the VL-10 strain was with100 mg/kg/day for 40 days. In the acute infection by the Y and VL-10 strains of T. cruzi, the treatment with a standard dose, but with a longer time of treatment (100 mg/kg/day for 40 days) presented the best results. Given these data, our results indicate that for BNZ, the theory of dose and time proportionality does not apply to the phases of infection.
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Affiliation(s)
- Kátia da Silva Fonseca
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
| | - Luísa Perin
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
| | - Nívia Carolina Nogueira de Paiva
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
| | - Beatriz Cristiane da Silva
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
| | - Thays Helena Chaves Duarte
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (T.H.C.D.); (F.d.S.M.)
| | - Flávia de Souza Marques
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (T.H.C.D.); (F.d.S.M.)
| | - Guilherme de Paula Costa
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
| | - Israel Molina
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
- Tropical Medicine and International Health Unit, Department of Infectious Diseases, Vall d’Hebron University Hospital, Universitat Autònoma de Barcelona, PROSICS Barcelona, 08035 Barcelona, Spain
| | - Rodrigo Correa-Oliveira
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
- Laboratory of Cellular and Molecular Immunology, René Rachou Research Center, Oswaldo Cruz Foundation, Belo Horizonte 30190-002, Brazil
| | - Paula Melo de Abreu Vieira
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
- Laboratory of Morphopathology, Department of Biological Sciences, Nucleus of Biological Sciences Research, Institute of Exact and Biological Sciences, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (T.H.C.D.); (F.d.S.M.)
| | - Cláudia Martins Carneiro
- Laboratory of Immunopathology, Nucleus of Biological Sciences Research, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil; (K.d.S.F.); (L.P.); (N.C.N.d.P.); (B.C.d.S.); (G.d.P.C.); (I.M.); (R.C.-O.); (P.M.d.A.V.)
- Department of Clinical Analysis, School of Pharmacy, Federal University of Ouro Preto, Ouro Preto 35400-000, Brazil
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Amlodipine Increases the Therapeutic Potential of Ravuconazole upon Trypanosoma cruzi Infection. Antimicrob Agents Chemother 2020; 64:AAC.02497-19. [PMID: 32423960 DOI: 10.1128/aac.02497-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 05/05/2020] [Indexed: 12/14/2022] Open
Abstract
Mining existing agents that enhance the therapeutic potential of ergosterol biosynthesis inhibitors (EBI) is a promising approach to improve Chagas disease chemotherapy. In this study, we evaluated the effect of ravuconazole, an EBI, combined with amlodipine, a calcium channel blocker, upon Trypanosoma cruzi experimental infection. In vitro assays confirmed the trypanocidal activity of both compounds in monotherapy and demonstrated an additive effect (sum of the fractional inhibitory concentration [ΣFIC] > 0.5) of the combined treatment without additional toxicity to host cells. In vivo experiments, using a murine model of the T. cruzi Y strain in a short-term protocol, demonstrated that amlodipine, although lacking trypanocidal activity, dramatically increased the antiparasitic activity of underdosing ravuconazole regimens. Additional analysis using long-term treatment (20 days) showed that parasitemia relapse until 60 days after treatment was significatively lower in mice treated with the combination (4 out of 14 mice) than ravuconazole monotherapy (10 out of 14 mice), even in the presence of immunosuppressant pressure. Furthermore, the combined therapy was well tolerated and protected the mice from mortality. The treatments also impacted on the cellular and humoral immune response of infected animals, inducing a reduction of serum cytokine levels in all ravuconazole-treated mice. Our findings demonstrate that amlodipine is efficacious in enhancing the antiparasitic activity of ravuconazole in an experimental model of T. cruzi infection and indicates a potential strategy to be explored in Chagas disease treatment.
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10
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Benznidazole self-emulsifying delivery system: A novel alternative dosage form for Chagas disease treatment. Eur J Pharm Sci 2020; 145:105234. [PMID: 31978590 DOI: 10.1016/j.ejps.2020.105234] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 01/09/2020] [Accepted: 01/21/2020] [Indexed: 12/14/2022]
Abstract
Benznidazole (BZ) tablets are a unique form of treatment available for treating Chagas disease. Development of a liquid formulation containing BZ easy to administer orally for the treatment of paediatric patients, particularly for newborns is urgently required, with the same efficacy, safety and suitable biopharmaceutical properties as BZ tablets. Self-emulsifying drug delivery systems (SEDDS) may improve bioavailability of drugs such as BZ, which have poor water solubility and low permeability. In this context, the aim of this work was to develop a liquid BZ-SEDDS formulation as an alternative to tablets and to evaluate its cytotoxicity in different host cell lines and its efficacy in experimental Trypanosoma cruzi infection in mice. The optimized SEDDS formulation (25 mg/ml of BZ) induced no cytotoxicity in H9c2, HepG2 and Caco2 cells in vitro at 25 μM level. BZ-SEDDS and free-BZ showed similar in vitro trypanocidal activity in H9c2 cells infected by T. cruzi Y strain, with IC50 values of 2.10 ± 0.41 μM and 1.29 ± 0.01 μM for BZ and BZ-SEDDS, respectively. A follow up of efficacy in an acute model of infected mice resulted in the same percentage of cure (57%) for both free-BZ and BZ-SEDDS- groups according to established parameters. Furthermore, no additional in vivo toxicity was observed in animals treated with BZ-SEDDS. Taken together, in vitro and in vivo data of BZ-SEDDS showed that the incorporation of BZ into SEDDS does not alter its potency, efficacy and safety. Thus, BZ-SEDDS can be a more practical and personalized orally administered liquid dosage form compared to suspension of crushed BZ-tablets to treat newborn and young children by emulsifying SEDDS in different aqueous liquids with advantage of dosing flexibility.
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11
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Sesquiterpene lactone potentiates the immunomodulatory, antiparasitic and cardioprotective effects on anti-Trypanosoma cruzi specific chemotherapy. Int Immunopharmacol 2019; 77:105961. [DOI: 10.1016/j.intimp.2019.105961] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 10/01/2019] [Accepted: 10/02/2019] [Indexed: 01/19/2023]
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12
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Mendonça AA, Gonçalves RV, Souza-Silva TG, Maldonado IR, Talvani A, Natali AJ, Novaes RD. Concomitant exercise training attenuates the cardioprotective effects of pharmacological therapy in a murine model of acute infectious myocarditis. Life Sci 2019; 230:141-149. [DOI: 10.1016/j.lfs.2019.05.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/20/2019] [Accepted: 05/22/2019] [Indexed: 02/06/2023]
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13
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Synergic Effect of Allopurinol in Combination with Nitroheterocyclic Compounds against Trypanosoma cruzi. Antimicrob Agents Chemother 2019; 63:AAC.02264-18. [PMID: 30962342 PMCID: PMC6535576 DOI: 10.1128/aac.02264-18] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 02/24/2019] [Indexed: 11/20/2022] Open
Abstract
Combination therapy has gained attention as a possible strategy for overcoming the limitations of the present therapeutic arsenal for Chagas disease. The aim of this study was to evaluate the effect of allopurinol in association with nitroheterocyclic compounds on infection with the Y strain of Trypanosoma cruzi The in vitro effect of allopurinol plus benznidazole or nifurtimox on intracellular amastigotes in infected H9c2 cells was assessed in a 72-h assay. The interactions were classified as synergic for both allopurinol-nifurtimox (sums of fractional inhibitory concentrations [∑FICs] = 0.49 ± 0.08) and allopurinol-benznidazole (∑FICs = 0.48 ± 0.09). In the next step, infected Swiss mice were treated with allopurinol at 30, 60, and 90 mg/kg of body weight and with benznidazole at 25, 50, and 75 mg/kg in monotherapy and in combination at the same doses; as a reference treatment, another group of animals received benznidazole at 100 mg/kg. Allopurinol in monotherapy led to a smaller or nil effect in the reduction of parasite load and mortality rate. Treatment with benznidazole at suboptimal doses induced a transient suppression of parasitaemia with subsequent relapse in all animals treated with 25 and 50 mg/kg and in 80% of those that received 75 mg/kg. Administration of the drugs in combination significantly increased the cure rate to 60 to 100% among mice treated with benznidazole at 75 mg/kg plus 30, 60, or 90 mg/kg of allopurinol. These results show a positive interaction between allopurinol and benznidazole, and since both drugs are commercially available, their use in combination may be considered for the assessment in the treatment of Chagas disease patients.
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14
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Outcome of E1224-Benznidazole Combination Treatment for Infection with a Multidrug-Resistant Trypanosoma cruzi Strain in Mice. Antimicrob Agents Chemother 2018; 62:AAC.00401-18. [PMID: 29555633 PMCID: PMC5971593 DOI: 10.1128/aac.00401-18] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 03/01/2018] [Indexed: 12/17/2022] Open
Abstract
Combination therapy has been proposed as an alternative therapeutic approach for the treatment of Chagas disease. In this study, we evaluated the effect of treatment with benznidazole combined with E1224 (ravuconazole prodrug) in an experimental murine model of acute infection. The first set of experiments assessed the range of E1224 doses required to induce parasitological cure using Trypanosoma cruzi strains with different susceptibilities to benznidazole (Y and Colombian). All E1224 doses were effective in suppressing the parasitemia and preventing death; however, parasitological cure was observed only in mice infected with Y strain. Considering these results, we evaluated the effect of combined treatment against Colombian, a multidrug-resistant T. cruzi strain. After exclusion of antagonistic effects using in vitro assays, infected mice were treated with E1224 and benznidazole in monotherapy or in combination at day 4 or 10 postinoculation. All treatments were well tolerated and effective in suppressing parasitemia; however, parasitological and PCR assays indicated no cure among mice treated with monotherapies. Intriguingly, the outcome of combination therapy was dependent on treatment onset. Early treatment using optimal doses of E1224-benznidazole induced a 100% cure rate, but this association could not eliminate a well-established infection. The beneficial effect of combination therapy was evidenced by further reductions of the patent parasitemia period in the group receiving combined therapy compared with monotherapies. Our results demonstrated a positive interaction between E1224 and benznidazole against murine T. cruzi infection using a multidrug-resistant strain and highlighted the importance of a stringent experimental model in the evaluation of new therapies.
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15
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Time and dose-dependence evaluation of nitroheterocyclic drugs for improving efficacy following Trypanosoma cruzi infection: A pre-clinical study. Biochem Pharmacol 2018; 148:213-221. [DOI: 10.1016/j.bcp.2018.01.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 01/03/2018] [Indexed: 10/18/2022]
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16
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Moreno-Viguri E, Jiménez-Montes C, Martín-Escolano R, Santivañez-Veliz M, Martin-Montes A, Azqueta A, Jimenez-Lopez M, Zamora Ledesma S, Cirauqui N, López de Ceráin A, Marín C, Sánchez-Moreno M, Pérez-Silanes S. In Vitro and in Vivo Anti-Trypanosoma cruzi Activity of New Arylamine Mannich Base-Type Derivatives. J Med Chem 2016; 59:10929-10945. [DOI: 10.1021/acs.jmedchem.6b00784] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Elsa Moreno-Viguri
- Department
of Organic and Pharmaceutical Chemistry, Institute of Tropical Health, Universidad de Navarra, Pamplona 31008, Spain
| | - Carmen Jiménez-Montes
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Rubén Martín-Escolano
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Mery Santivañez-Veliz
- Department
of Organic and Pharmaceutical Chemistry, Institute of Tropical Health, Universidad de Navarra, Pamplona 31008, Spain
| | - Alvaro Martin-Montes
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Amaya Azqueta
- Department
of Pharmacology and Toxicology, Universidad de Navarra, Pamplona 31008, Spain
- IdiSNA, Navarra
Institute for Health Research, Recinto de Complejo Hospitalario de
Navarra, Pamplona 31008, Spain
| | - Marina Jimenez-Lopez
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Salvador Zamora Ledesma
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Nuria Cirauqui
- Department
of Pharmaceutical Sciences, Federal University of Rio de Janeiro, Rio de
Janeiro 21949-900, Brazil
| | - Adela López de Ceráin
- Department
of Pharmacology and Toxicology, Universidad de Navarra, Pamplona 31008, Spain
- IdiSNA, Navarra
Institute for Health Research, Recinto de Complejo Hospitalario de
Navarra, Pamplona 31008, Spain
| | - Clotilde Marín
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Manuel Sánchez-Moreno
- Departamento
de Parasitología, Instituto de Investigación Biosanitaria
(ibs.GRANADA), Hospitales Universitarios de Granada/Universidad de Granada, Granada 18014, Spain
| | - Silvia Pérez-Silanes
- Department
of Organic and Pharmaceutical Chemistry, Institute of Tropical Health, Universidad de Navarra, Pamplona 31008, Spain
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Santos FM, Mazzeti AL, Caldas S, Gonçalves KR, Lima WG, Torres RM, Bahia MT. Chagas cardiomyopathy: The potential effect of benznidazole treatment on diastolic dysfunction and cardiac damage in dogs chronically infected with Trypanosoma cruzi. Acta Trop 2016; 161:44-54. [PMID: 27215760 DOI: 10.1016/j.actatropica.2016.05.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 04/24/2016] [Accepted: 05/15/2016] [Indexed: 10/21/2022]
Abstract
Cardiac involvement represents the main cause of mortality among patients with Chagas disease, and the relevance of trypanocidal treatment to improving diastolic dysfunction is still doubtful. In the present study, we used a canine model infected with the benznidazole-sensitive Berenice-78 Trypanosoma cruzi strain to verify the efficacy of an etiologic treatment in reducing the parasite load and ameliorating cardiac muscle tissue damage and left ventricular diastolic dysfunction in the chronic phase of the infection. The effect of the treatment on reducing the parasite load was monitored by blood PCR and blood culture assays, and the effect of the treatment on the outcome of heart tissue damage and on diastolic function was evaluated by histopathology and echo Doppler cardiogram. The benefit of the benznidazole-treatment in reducing the parasite burden was demonstrated by a marked decrease in positive blood culture and PCR assay results until 30days post-treatment. At this time, the PCR and blood culture assays yielded negative results for 82% of the treated animals, compared with only 36% of the untreated dogs. However, a progressive increase in the parasite load could be detected in the peripheral blood for one year post-treatment, as evidenced by a progressive increase in positive results for both the PCR and the blood culture assays at follow-up. The parasite load reduction induced by treatment was compatible with the lower degree of tissue damage among animals euthanized in the first month after treatment and with the increased cardiac damage after this period, reaching levels similar to those in untreated animals at the one-year follow-up. The two infected groups also presented similar, significantly smaller values for early tissue septal velocity (E' SIV) than the non-infected dogs did at this later time. Moreover, in the treated animals, an increase in the E/E' septal tissue filling pressure ratio was observed when compared with basal values as well as with values in non-infected dogs. These findings strongly suggest that the temporary reduction in the parasite load that was induced by benznidazole treatment was not able to prevent myocardial lesions and diastolic dysfunction for long after treatment.
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18
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Curcumin Enhances the Anti-Trypanosoma cruzi Activity of Benznidazole-Based Chemotherapy in Acute Experimental Chagas Disease. Antimicrob Agents Chemother 2016; 60:3355-64. [PMID: 27001816 DOI: 10.1128/aac.00343-16] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 03/10/2016] [Indexed: 12/20/2022] Open
Abstract
Although curcumin can increase the effectiveness of drugs against malaria, combination therapies using the molecule have never been investigated in Chagas disease (ChD). Therefore, we evaluated the efficacy of curcumin as a complementary strategy to benznidazole (Bz)-based chemotherapy in mice acutely infected with Trypanosoma cruzi Eighty-four 12-week-old Swiss mice were equally randomized into seven groups: uninfected (NI), T. cruzi infected and untreated (INF), infected and treated with 100 mg/kg of body weight Bz (B100), 50 mg/kg Bz (B50), 100 mg/kg curcumin (C100), 100 mg/kg Bz plus 100 mg/kg curcumin (B100 plus C100), and 50 mg/kg Bz plus 100 mg/kg curcumin (B50 plus C100). After microscopic identification of blood trypomastigotes (4 days after inoculation), both drugs were administered by gavage once a day for 20 days. Curcumin showed limited antiparasitic, anti-inflammatory, and antioxidant effects when administered alone. When curcumin and Bz were combined, there was a drastic reduction in parasitemia, parasite load, mortality, anti-T. cruzi IgG reactivity, circulating levels of cytokines (gamma interferon [IFN-γ], interleukin 4 [IL-4], and MIP1-α), myocardial inflammation, and morphological and oxidative cardiac injury; these results exceeded the isolated effects of Bz. The combination of Bz and curcumin was also effective at mitigating liver toxicity triggered by Bz, increasing the parasitological cure rate, and preventing infection recrudescence in noncured animals, even when the animals were treated with 50% of the recommended therapeutic dose of Bz. By limiting the toxic effects of Bz and enhancing its antiparasitic efficiency, the combination of the drug with curcumin may be a relevant therapeutic strategy that is possibly better tolerated in ChD treatment than Bz-based monotherapy.
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Olmo F, Gómez-Contreras F, Navarro P, Marín C, Yunta MJ, Cano C, Campayo L, Martín-Oliva D, Rosales MJ, Sánchez-Moreno M. Synthesis and evaluation of in vitro and in vivo trypanocidal properties of a new imidazole-containing nitrophthalazine derivative. Eur J Med Chem 2015; 106:106-19. [DOI: 10.1016/j.ejmech.2015.10.034] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 10/18/2015] [Accepted: 10/20/2015] [Indexed: 11/30/2022]
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20
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Revisiting the Posttherapeutic Cure Criterion in Chagas Disease: Time for New Methods, More Questions, Doubts, and Polemics or Time to Change Old Concepts? BIOMED RESEARCH INTERNATIONAL 2015; 2015:652985. [PMID: 26583124 PMCID: PMC4637035 DOI: 10.1155/2015/652985] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 08/10/2015] [Indexed: 01/17/2023]
Abstract
One of the most relevant issues beyond the effectiveness of etiological treatment of Chagas disease is the lack of consensual/feasible tools to identify and certify the definitive parasitological cure. Several methods of distinct natures (parasitological, serological, and molecular) have been continuously proposed and novel perspectives are currently under investigation. Although the simultaneous use of distinct tests may offer better contributions and advances, it also leads to controversies of interpretation, with lack of mutual consent of cure criterion amongst researchers and physicians. In fact, when distinct host compartments (blood/tissues) are evaluated and explored, novel questions may arise due to the nature and sensitivity limit of each test. This short analytical review intends to present a chronological and critical overview and discuss the state-of-the-art distinct devices available for posttherapeutic cure assessment in Chagas disease, their contributions, meanings, and interpretation, aiming to point out the major gaps and propose novel insight for future perspectives of posttherapeutic management of Chagas disease patients.
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Antitrypanosomal Treatment with Benznidazole Is Superior to Posaconazole Regimens in Mouse Models of Chagas Disease. Antimicrob Agents Chemother 2015; 59:6385-94. [PMID: 26239982 DOI: 10.1128/aac.00689-15] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/19/2015] [Indexed: 11/20/2022] Open
Abstract
Two CYP51 inhibitors, posaconazole and the ravuconazole prodrug E1224, were recently tested in clinical trials for efficacy in indeterminate Chagas disease. The results from these studies show that both drugs cleared parasites from the blood of infected patients at the end of the treatment but that parasitemia rebounded over the following months. In the current study, we sought to identify a dosing regimen of posaconazole that could permanently clear Trypanosoma cruzi from mice with experimental Chagas disease. Infected mice were treated with posaconazole or benznidazole, an established Chagas disease drug, and parasitological cure was defined as an absence of parasitemia recrudescence after immunosuppression. Twenty-day therapy with benznidazole (10 to 100 mg/kg of body weight/day) resulted in a dose-dependent increase in antiparasitic activity, and the 100-mg/kg regimen effected parasitological cure in all treated mice. In contrast, all mice remained infected after a 25-day treatment with posaconazole at all tested doses (10 to 100 mg/kg/day). Further extension of posaconazole therapy to 40 days resulted in only a marginal improvement of treatment outcome. We also observed similar differences in antiparasitic activity between benznidazole and posaconazole in acute T. cruzi heart infections. While benznidazole induced rapid, dose-dependent reductions in heart parasite burdens, the antiparasitic activity of posaconazole plateaued at low doses (3 to 10 mg/kg/day) despite increasing drug exposure in plasma. These observations are in good agreement with the outcomes of recent phase 2 trials with posaconazole and suggest that the efficacy models combined with the pharmacokinetic analysis employed here will be useful in predicting clinical outcomes of new drug candidates.
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Assíria Fontes Martins T, de Figueiredo Diniz L, Mazzeti AL, da Silva do Nascimento ÁF, Caldas S, Caldas IS, de Andrade IM, Ribeiro I, Bahia MT. Benznidazole/Itraconazole Combination Treatment Enhances Anti-Trypanosoma cruzi Activity in Experimental Chagas Disease. PLoS One 2015; 10:e0128707. [PMID: 26076455 PMCID: PMC4468053 DOI: 10.1371/journal.pone.0128707] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 04/29/2015] [Indexed: 11/29/2022] Open
Abstract
The nitroheterocyclic drugs nifurtimox and benznidazole are first-line drugs available to treat Chagas disease; however, they have limitations, including long treatment courses and toxicity. Strategies to overcome these limitations include the identification of new drugs with specific target profiles, re-dosing regimens for the current drugs, drug repositioning and combination therapy. In this work, we evaluated combination therapy as an approach for optimization of the current therapeutic regimen for Chagas disease. The curative action of benznidazole/itraconazole combinations was explored in an established infection of the mice model with the T. cruzi Y strain. The activities of the benznidazole/itraconazole combinations were compared with the results from those receiving the same dosage of each individual drug. The administration of benznidazole/itraconazole in combination eliminated parasites from the blood more efficiently than each drug alone. Here, there was a significant reduction of the number of treatment days (number of doses) necessary to induce parasitemia suppression with the benznidazole/itraconazole combination, as compared to each compound administered alone. These results clearly indicate the enhanced effects of these drugs in combination, particularly at the dose of 75 mg/kg, as the effects observed with the drug combinations were four times more effective than those of each drug used alone. Moreover, benznidazole/itraconazole treatment was shown to prevent or decrease the typical lesions associated with chronic experimental Chagas disease, as illustrated by similar levels of inflammatory cells and fibrosis in the cardiac muscle tissue of healthy and treated mice. These results emphasize the importance of exploring the potential of combination treatments with currently available compounds to specifically treat Chagas disease.
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Affiliation(s)
- Tassiane Assíria Fontes Martins
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
| | - Lívia de Figueiredo Diniz
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
- Departamento de Patologia e Parasitologia, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Alfenas, Minas Gerais, Brazil
| | - Ana Lia Mazzeti
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
| | - Álvaro Fernando da Silva do Nascimento
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
| | - Sérgio Caldas
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
- Fundação Ezequiel Dias, Belo Horizonte, Minas Gerais, Brazil
| | - Ivo Santana Caldas
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
- Departamento de Patologia e Parasitologia, Instituto de Ciências Biomédicas, Universidade Federal de Alfenas, Alfenas, Minas Gerais, Brazil
| | - Isabel Mayer de Andrade
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
| | - Isabela Ribeiro
- Drugs for Neglected Disease initiative (DNDi), 1202 Geneva, Switzerland
| | - Maria Terezinha Bahia
- Laboratório de Doenças Parasitárias, Escola de Medicina & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil
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23
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Gruendling AP, Massago M, Teston APM, Monteiro WM, Kaneshima EN, Araújo SM, Gomes ML, Barbosa MDGV, Toledo MJO. Impact of benznidazole on infection course in mice experimentally infected with Trypanosoma cruzi I, II, and IV. Am J Trop Med Hyg 2015; 92:1178-89. [PMID: 25940197 DOI: 10.4269/ajtmh.13-0690] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 11/01/2014] [Indexed: 11/07/2022] Open
Abstract
American trypanosomiasis is an emerging zoonosis in the Brazilian Amazon. Studies on benznidazole (BZ) chemotherapy with Trypanosoma cruzi from this region have great relevance, given the different discrete typing units (DTUs) that infect humans in the Amazon and other regions of Brazil. We performed a parasitological, histopathological, and molecular analysis of mice inoculated with strains of T. cruzi I, II, and IV that were BZ-treated during the acute phase of infection. Groups of Swiss mice were inoculated; 13 received oral BZ, whereas the other 13 comprised the untreated controls. Unlike parasitemia, the infectivity and mortality did not vary among the DTUs. Trypanosoma cruzi DNA was detected in all tissues analyzed and the proportion of organs parasitized varied with the parasite DTU. The BZ treatment reduced the most parasitological parameters, tissue parasitism and the inflammatory processes at all infection stages and for all DTUs. However, the number of significant reductions varied according to the DTU and infection phase.
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Affiliation(s)
- Ana Paula Gruendling
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Miyoko Massago
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Ana Paula M Teston
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Wuelton M Monteiro
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Edilson N Kaneshima
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Silvana M Araújo
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Mônica L Gomes
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Maria das Graças V Barbosa
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
| | - Max Jean O Toledo
- Post-Graduate Program in Health Sciences (Programa de Pós-graduação em Ciências da Saúde), Maringá State University (Universidade Estadual de Maringá, UEM), Maringá, Paraná, Brazil; Department of Basic Health Sciences, Health Sciences Center, (Departamento de Ciências Básicas da Saúde, Centro de Ciências da Saúde), UEM, Maringá, Paraná, Brazil; Post-Graduate Program in Tropical Medicine (Programa de Pós-Graduação em Medicina Tropical), Dr. Heitor Vieira Dourado Foundation for Tropical Medicine (Fundação de Medicina Tropical Dr. Heitor Vieira Dourado)/Amazonas State University (Universidade do Estado do Amazonas), Manaus, Amazonas, Brazil
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Antitrypanosomal activity of fexinidazole metabolites, potential new drug candidates for Chagas disease. Antimicrob Agents Chemother 2014; 58:4362-70. [PMID: 24841257 DOI: 10.1128/aac.02754-13] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study was designed to verify the in vivo efficacy of sulfoxide and sulfone fexinidazole metabolites following oral administration in a murine model of Chagas disease. Female Swiss mice infected with the Y strain of Trypanosoma cruzi were treated orally once per day with each metabolite at doses of 10 to 100 mg/kg of body weight for a period of 20 days. Parasitemia was monitored throughout, and cures were detected by parasitological and PCR assays. The results were compared with those achieved with benznidazole treatment at the same doses. Fexinidazole metabolites were effective in reducing the numbers of circulating parasites and protecting mice against death, compared with untreated mice, but without providing cures at daily doses of 10 and 25 mg/kg. Both metabolites were effective in curing mice at 50 mg/kg/day (30% to 40%) and 100 mg/kg/day (100%). In the benznidazole-treated group, parasitological cure was detected only in animals treated with the higher dose of 100 mg/kg/day (80%). Single-dose pharmacokinetic parameters for each metabolite were obtained from a parallel group of uninfected mice and were used to estimate the profiles following repeated doses. Pharmacokinetic data suggested that biological efficacy most likely resides with the sulfone metabolite (or subsequent reactive metabolites formed following reduction of the nitro group) following administration of either the sulfoxide or the sulfone and that prolonged plasma exposure over the 24-h dosing window is required to achieve high cure rates. Fexinidazole metabolites were effective in treating T. cruzi in a mouse model of acute infection, with cure rates superior to those achieved with either fexinidazole itself or benznidazole.
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Scorpiand-like azamacrocycles prevent the chronic establishment of Trypanosoma cruzi in a murine model. Eur J Med Chem 2013; 70:189-98. [DOI: 10.1016/j.ejmech.2013.09.048] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Revised: 09/27/2013] [Accepted: 09/29/2013] [Indexed: 12/20/2022]
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Diniz LDF, Urbina JA, de Andrade IM, Mazzeti AL, Martins TAF, Caldas IS, Talvani A, Ribeiro I, Bahia MT. Benznidazole and posaconazole in experimental Chagas disease: positive interaction in concomitant and sequential treatments. PLoS Negl Trop Dis 2013; 7:e2367. [PMID: 23967360 PMCID: PMC3744424 DOI: 10.1371/journal.pntd.0002367] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 07/02/2013] [Indexed: 01/12/2023] Open
Abstract
Background Current chemotherapy for Chagas disease is unsatisfactory due to its limited efficacy, particularly in the chronic phase, with frequent side effects that can lead to treatment discontinuation. Combined therapy is envisioned as an ideal approach since it may improve treatment efficacy whilst decreasing toxicity and the likelihood of resistance development. We evaluated the efficacy of posaconazole in combination with benznidazole on Trypanosoma cruzi infection in vivo. Methods and Findings Benznidazole and posaconazole were administered individually or in combination in an experimental acute murine infection model. Using a rapid treatment protocol for 7 days, the combined treatments were more efficacious in reducing parasitemia levels than the drugs given alone, with the effects most evident in combinations of sub-optimal doses of the drugs. Subsequently, the curative action of these drug combinations was investigated, using the same infection model and 25, 50, 75 or 100 mg/kg/day (mpk) of benznidazole in combination with 5, 10 or 20 mpk of posaconazole, given alone or concomitantly for 20 days. The effects of the combination treatments on parasitological cures were higher than the sum of such effects when the drugs were administered separately at the same doses, indicating synergistic activity. Finally, sequential therapy experiments were carried out with benznidazole or posaconazole over a short interval (10 days), followed by the second drug administered for the same period of time. It was found that the sequence of benznidazole (100 mpk) followed by posaconazole (20 mpk) provided cure rates comparable to those obtained with the full (20 days) treatments with either drug alone, and no cure was observed for the short treatments with drugs given alone. Conclusions Our data demonstrate the importance of investigating the potential beneficial effects of combination treatments with marketed compounds, and showed that combinations of benznidazole with posaconazole have a positive interaction in murine models of Chagas disease. In this study, we investigated the efficacy of posaconazole in combination with benznidazole against Trypanosoma cruzi acute infections in mice, to support the potential clinical evaluation of such combination therapy for Chagas disease. The curative action of benznidazole/posaconazole combinations was explored in an established acute infection model with the Y strain in which benznidazole and posaconazole treatments induced a 70% and 80% cure rate, respectively, when administered alone at optimal doses. When tested in combination, a 80% to 90% cure rate was detected in mice receiving 25, 50 or 75 mpk of benznidazole, plus 5 or 10 mpk of posaconazole, while treatment with the sub-optimal doses of the drugs given alone induced only 0–43% cures, indicating synergistic effects. Finally, sequential short (10 days) treatments with benznidazole (100 mpk) followed by posaconazole (20 mpk) led to an 80% cure rate, comparable with full-length treatments with either drug given alone, while no cures were observed for short treatments with single drugs. Our results demonstrate that it is possible to achieve the same or better therapeutic effect using lower dosages of posaconazole and benznidazole in combination, decreasing treatment costs and potential toxicity.
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Affiliation(s)
- Lívia de Figueiredo Diniz
- Laboratório de Doença de Chagas, Departamento de Ciências Biológicas & Núcleo de Pesquisas em Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil.
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Bustamante JM, Craft JM, Crowe BD, Ketchie SA, Tarleton RL. New, combined, and reduced dosing treatment protocols cure Trypanosoma cruzi infection in mice. J Infect Dis 2013; 209:150-62. [PMID: 23945371 DOI: 10.1093/infdis/jit420] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The development of treatment protocols with reduced toxicity and equivalent or improved efficacy for Trypanosoma cruzi infection is a priority. We tested the effectiveness of benznidazole (BZ), nifurtimox (NFX), other prospective drugs in intermittent and combined treatment protocols to cure T. cruzi infection initiated with susceptible and drug-resistant parasite strains. A 40-day course of BZ, NFX, or the oxaborale AN4169 cured 100% of mice, whereas posaconazole (POS), and NTLA-1 (a nitro-triazole) cured approximately 90% and 20% of mice, respectively. Reducing the overall dosage of BZ or NFX by using an intermittent (once every 5 days) schedule or combining 5 daily doses of POS with 7 intermittent doses of BZ also provided approximately 100% cure. T. cruzi strains resistant to BZ were also found to be resistant to other drugs (POS), and extending the time of treatment or combining drugs did not increase cure rates with these isolates. Thus, dosing schedules for anti-T. cruzi compounds should be determined empirically, and compounds targeting different pathways may be combined to yield effective therapies with reduced toxicity. This work also suggests that standard treatment protocols using BZ and NFX may be significantly overdosing patients, perhaps contributing to the adverse events.
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Teston APM, Monteiro WM, Reis D, Bossolani GDP, Gomes ML, de Araújo SM, Bahia MT, Barbosa MGV, Toledo MJO. In vivo susceptibility to benznidazole of Trypanosoma cruzi strains from the western Brazilian Amazon. Trop Med Int Health 2012; 18:85-95. [PMID: 23130989 DOI: 10.1111/tmi.12014] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To assess the susceptibility of Trypanosoma cruzi strains from Amazon to benznidazole. METHODS We studied 23 strains of T. cruzi obtained from humans in the acute phase of Chagas disease, triatomines and marsupials in the state of Amazonas and from chronic patients and triatomines in the state of Paraná, Brazil. The strains were classified as TcI (6), TcII (4) and TcIV (13). For each strain, 20 Swiss mice were inoculated: 10 were treated orally with benznidazole 100 mg/kg/day (TBZ group) for 20 consecutive days and 10 comprised the untreated control group (NT). Fresh blood examination, haemoculture (HC), PCR, and ELISA were used to monitor the cure. RESULTS The overall cure rate was 60.5% (109/180 mice) and varied widely among strains. The strains were classified as resistant, partially resistant or susceptible to benznidazole, irrespective of discrete typing units (DTUs), geographical origin or host. However, the TcI strains from Amazonas were significantly (P = 0.028) more sensitive to benznidazole than the TcI strains from Paraná. The number of parasitological, molecular and serological parameters that were significantly reduced by benznidazole treatment also varied among the DTUs; the TBZ group of mice inoculated with TcIV strains showed more reductions (8/9) than those with TcI and TcII strains. CONCLUSIONS Benznidazole resistance was observed among natural populations of the parasite in the Amazon, even in those never exposed to the drug.
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Affiliation(s)
- Ana P M Teston
- Post-Graduation Program in Health Sciences, State University of Maringá, Paraná, Brazil
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Fexinidazole: a potential new drug candidate for Chagas disease. PLoS Negl Trop Dis 2012; 6:e1870. [PMID: 23133682 PMCID: PMC3486905 DOI: 10.1371/journal.pntd.0001870] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 09/05/2012] [Indexed: 12/02/2022] Open
Abstract
Background New safe and effective treatments for Chagas disease (CD) are urgently needed. Current chemotherapy options for CD have significant limitations, including failure to uniformly achieve parasitological cure or prevent the chronic phase of CD, and safety and tolerability concerns. Fexinidazole, a 2-subsituted 5-nitroimidazole drug candidate rediscovered following extensive compound mining by the Drugs for Neglected Diseases initiative and currently in Phase I clinical study for the treatment of human African trypanosomiasis, was evaluated in experimental models of acute and chronic CD caused by different strains of Trypanosoma cruzi. Methods and Findings We investigated the in vivo activity of fexinidazole against T. cruzi, using mice as hosts. The T. cruzi strains used in the study were previously characterized in murine models as susceptible (CL strain), partially resistant (Y strain), and resistant (Colombian and VL-10 strains) to the drugs currently in clinical use, benznidazole and nifurtimox. Our results demonstrated that fexinidazole was effective in suppressing parasitemia and preventing death in infected animals for all strains tested. In addition, assessment of definitive parasite clearance (cure) through parasitological, PCR, and serological methods showed cure rates of 80.0% against CL and Y strains, 88.9% against VL-10 strain, and 77.8% against Colombian strain among animals treated during acute phase, and 70% (VL-10 strain) in those treated in chronic phase. Benznidazole had a similar effect against susceptible and partially resistant T. cruzi strains. Fexinidazole treatment was also shown to reduce myocarditis in all animals infected with VL-10 or Colombian resistant T. cruzi strains, although parasite eradication was not achieved in all treated animals at the tested doses. Conclusions Fexinidazole is an effective oral treatment of acute and chronic experimental CD caused by benznidazole-susceptible, partially resistant, and resistant T. cruzi. These findings illustrate the potential of fexinidazole as a drug candidate for the treatment of human CD. This study describes the in vivo activity of fexinidazole against Trypanosoma cruzi, the protozoan parasite causing Chagas disease, using mice infected with parasite strains with varying susceptibility to benznidazole, the standard treatment for Chagas. Fexinidazole and benznidazole were shown to have similar activity against benznidazolesusceptible and partially resistant T. cruzi strains (CL and Y), but fexinidazole had potent activity against benznidazole-resistant strains (VL-10 and Colombian). Fexinidazole treatment resulted in parasitological cure during acute disease phase in 88.9% of mice infected with the VL-10 strain and 78% with Colombian strain; benznidazole treatment did not result in cure in animals infected with these strains. Fexinidazole treatment was also shown to reduce myocarditis in all VL-10- and Colombian-infected animals, although parasite eradication was not achieved in all treated animals. These data demonstrate that it is possible to achieved better cure rates with fexinidazole in these experimental infection models than what is achieved with the standard benznidazole at the doses tested in this animal study benznidazole treatment regimen.
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Sánchez-Moreno M, Gómez-Contreras F, Navarro P, Marín C, Olmo F, Yunta MJR, Sanz AM, Rosales MJ, Cano C, Campayo L. Phthalazine derivatives containing imidazole rings behave as Fe-SOD inhibitors and show remarkable anti-T. cruzi activity in immunodeficient-mouse mode of infection. J Med Chem 2012; 55:9900-13. [PMID: 23043291 DOI: 10.1021/jm3011004] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of new phthalazine derivatives 1-4 containing imidazole rings were prepared. The monoalkylamino substituted derivatives 2 and 4 were more active in vitro against T. cruzi and less toxic against Vero cells than both their disubstituted analogues and the reference drug benznidazole. Compounds 2 and 4 highly inhibited the antioxidant parasite enzyme Fe-SOD, and molecular modeling suggested that they interact with the H-bonding system of the iron atom moiety. In vivo tests on the acute phase of Chagas disease gave parasitemia inhibition values twice those of benznidazole, and a remarkable decrease in the reactivation of parasitemia was found in the chronic phase for immunodeficient mice. Glucose metabolism studies showed that compounds 1-4 did not affect the succinate pathway but originated important changes in the excretion of pyruvate metabolites. The morphological alterations found in epimastigotes treated with 1-4 confirmed extensive cytoplasm damage and a high mortality rate of parasites.
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Affiliation(s)
- Manuel Sánchez-Moreno
- Departamento de Parasitología, Facultad de Ciencias, Universidad de Granada, E-18071 Granada, Spain.
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Pharmacological characterization, structural studies, and in vivo activities of anti-Chagas disease lead compounds derived from tipifarnib. Antimicrob Agents Chemother 2012; 56:4914-21. [PMID: 22777048 DOI: 10.1128/aac.06244-11] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Chagas disease, caused by the protozoan pathogen Trypanosoma cruzi, remains a challenging infection due to the unavailability of safe and efficacious drugs. Inhibitors of the trypanosome sterol 14α-demethylase enzyme (CYP51), including azole antifungal drugs, are promising candidates for development as anti-Chagas disease drugs. Posaconazole is under clinical investigation for Chagas disease, although the high cost of this drug may limit its widespread use. We have previously reported that the human protein farnesyltransferase (PFT) inhibitor tipifarnib has potent anti-T. cruzi activity by inhibiting the CYP51 enzyme. Furthermore, we have developed analogs that minimize the PFT-inhibitory activity and enhance the CYP51 inhibition. In this paper, we describe the efficacy of the lead tipifarnib analog compared to that of posaconazole in a murine model of T. cruzi infection. The plasma exposure profiles for each compound following a single oral dose in mice and estimated exposure parameters after repeated twice-daily dosing for 20 days are also presented. The lead tipifarnib analog had potent suppressive activity on parasitemia in mice but was unsuccessful at curing mice, whereas posaconazole as well as benznidazole cured 3 of 5 and 4 of 6 mice, respectively. The efficacy results are consistent with posaconazole having substantially higher predicted exposure than that of the tipifarnib analog after repeat twice-daily administration. Further changes to the tipifarnib analogs to reduce plasma clearance are therefore likely to be important. A crystal structure of a trypanosomal CYP51 bound to a tipifarnib analog is reported here and provides new insights to guide structure-based drug design for further optimized compounds.
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Veloso VM, Guedes PMDM, de Lana M, Martins HR, Carneiro CM, da Câmara ACJ, D'Ávila DA, Caldas IS, Galvão LMDC, Chiari E, Bahia MT. Genetic modulation in Be-78 and Y Trypanosoma cruzi strains after long-term infection in Beagle dogs revealed by molecular markers. INFECTION GENETICS AND EVOLUTION 2012; 12:1128-35. [PMID: 22554652 DOI: 10.1016/j.meegid.2012.03.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2011] [Revised: 03/13/2012] [Accepted: 03/20/2012] [Indexed: 11/26/2022]
Abstract
The genetic profile of Trypanosoma cruzi was evaluated in parasite populations isolated from Beagle dogs experimentally infected with Be-78 and Y strains that present distinct biological and genetic characteristics. Molecular characterization of the isolates obtained 30days and 2years after infection was carried out. For typing MLEE, sequence polymorphisms of the mitochondrial cytochrome oxidase subunit II gene (COII) and RAPD profiles were used. The profiles of MLEE were the same for the parental Be-78 strains as their respective isolates. However, changes of MLEE profile were observed in two T. cruzi isolates from dogs inoculated with Y strain. Changes in the mitochondrial DNA (COII) and RAPD profiles of the Y strain were also observed. The dendogram constructed by UPGMA with RAPD results indicated two major branches. Global data show that the genetic modulation in polyclonal strains during the long-term infection occurred and was strain-dependent. This study still suggests that each host (here each dog) harbors a determinate T. cruzi population that may change or be modulated throughout long-term infection. This might to hinder the observation of correlation between the genetics of T. cruzi and their biological properties and behavior in different host species due to the complexity of the parasite-host interaction in which probably the genetic background of both should be considered.
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Affiliation(s)
- Vanja Maria Veloso
- Departamento de Farmácia, Escola de Farmácia, Universidade Federal de Ouro Preto, Rua Costa Sena 171, Centro, CEP 35400-000 Ouro Preto, MG, Brazil.
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Pereira AC, Magalhães LG, Gonçalves UO, Luz PP, Moraes ACG, Rodrigues V, da Matta Guedes PM, da Silva Filho AA, Cunha WR, Bastos JK, Nanayakkara NPD, e Silva MLA. Schistosomicidal and trypanocidal structure-activity relationships for (±)-licarin A and its (-)- and (+)-enantiomers. PHYTOCHEMISTRY 2011; 72:1424-1430. [PMID: 21570099 DOI: 10.1016/j.phytochem.2011.04.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 04/08/2011] [Accepted: 04/13/2011] [Indexed: 05/30/2023]
Abstract
(±)-Licarin A (1) was obtained by oxidative coupling, and its enantiomers, (-)-licarin A (2) and (+)-licarin A (3), were resolved by chiral HPLC. Schistosomicidal and trypanocidal activities of these compounds were evaluated in vitro against Schistosoma mansoni adult worms and trypomastigote forms of Trypanosoma cruzi. The racemic mixture (1) displayed significant schistosomicidal activity with an LC₅₀ value of 53.57 μM and moderate trypanocidal activity with an IC₅₀ value of 127.17 μM. On the other hand, the (-)-enantiomer (2), displaying a LC₅₀ value of 91.71 μM, was more active against S. mansoni than the (+)-enantiomer (3), which did not show activity. For the trypanocidal assay, enantiomer 2 showed more significant activity (IC₅₀ of 23.46 μM) than enantiomer 3, which showed an IC₅₀ value of 87.73 μM. Therefore, these results suggest that (±)-licarin A (1) and (-)-licarin A (2) are promising compounds that could be used for the development of schistosomicidal and trypanocidal agents.
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Affiliation(s)
- A C Pereira
- Grupo de Pesquisas em Produtos Naturais, Núcleo de Ciências Exatas e Tecnológicas, Universidade de Franca, Avenida Dr. Armando Salles de Oliveira 2001, 14404-600 Franca, SP, Brazil
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Maximiano FP, Costa GHY, de Sá Barreto LCL, Bahia MT, Cunha-Filho MSS. Development of effervescent tablets containing benznidazole complexed with cyclodextrin. J Pharm Pharmacol 2011; 63:786-93. [DOI: 10.1111/j.2042-7158.2011.01284.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Abstract
Objectives
Benznidazole (BNZ), the primary chemotherapy agent used to treat Chagas disease, has poor aqueous solubility, which results in low bioavailability. The purpose of this work was to develop stable effervescent tablets using an inclusion complex of BNZ with cyclodextrin (CD).
Method
In the first phase, different CDs were evaluated according to their ability to improve the aqueous solubility of BNZ. Then, inclusion complexes of BNZ in the solid state were produced by the kneading method and the complexes were evaluated using several physical–chemical assays. Finally, effervescent tablets were prepared according to a complete 32 factorial design. The effects of the concentration of CD and effervescent mixture on the dissolution rate and physical stability of tablets were evaluated.
Key findings
Hydroxypropyl-β-cyclodextrin produced the greatest improvement in the aqueous solubility of BNZ, almost 20-times greater than the water system. Solid systems produced with BNZ and CD showed physical–chemical interactions and increased the drug dissolution rate, suggesting the formation of a true solid inclusion complex. Moreover, the effervescent matrix of the tablets was effective in improving the dissolution behaviour of BNZ complexed with CD.
Conclusions
Effervescent tablets produced using an inclusion complex of BNZ with CD suggest a possible improvement in the bioavailability of BNZ, and this could represent a relevant advance in Chagas therapy.
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Affiliation(s)
- Flávia Pires Maximiano
- Escola de Farmácia, Universidade Federal de Ouro Preto, Rua Costa Sena, Centro, Ouro Preto-MG, Brazil
| | | | - Lívia Cristina Lira de Sá Barreto
- Instituto de Ciências da Saúde, Campus Universitário de Sinop, Universidade Federal do Mato Grosso, Avenida Alexandre Ferronato, Setor Industrial, Sinop-MT, Brazil
| | - Maria Terezinha Bahia
- Instituto de Ciências Exatas e Biológicas, Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, ICEB, Bauxita, Ouro Preto-MG, Brazil
| | - Marcílio S S Cunha-Filho
- Instituto de Ciências da Saúde, Campus Universitário de Sinop, Universidade Federal do Mato Grosso, Avenida Alexandre Ferronato, Setor Industrial, Sinop-MT, Brazil
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Romanha AJ, Castro SLD, Soeiro MDNC, Lannes-Vieira J, Ribeiro I, Talvani A, Bourdin B, Blum B, Olivieri B, Zani C, Spadafora C, Chiari E, Chatelain E, Chaves G, Calzada JE, Bustamante JM, Freitas-Junior LH, Romero LI, Bahia MT, Lotrowska M, Soares M, Andrade SG, Armstrong T, Degrave W, Andrade ZDA. In vitro and in vivo experimental models for drug screening and development for Chagas disease. Mem Inst Oswaldo Cruz 2010; 105:233-8. [PMID: 20428688 DOI: 10.1590/s0074-02762010000200022] [Citation(s) in RCA: 271] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2009] [Accepted: 01/26/2010] [Indexed: 11/22/2022] Open
Abstract
Chagas disease, a neglected illness, affects nearly 12-14 million people in endemic areas of Latin America. Although the occurrence of acute cases sharply has declined due to Southern Cone Initiative efforts to control vector transmission, there still remain serious challenges, including the maintenance of sustainable public policies for Chagas disease control and the urgent need for better drugs to treat chagasic patients. Since the introduction of benznidazole and nifurtimox approximately 40 years ago, many natural and synthetic compounds have been assayed against Trypanosoma cruzi, yet only a few compounds have advanced to clinical trials. This reflects, at least in part, the lack of consensus regarding appropriate in vitro and in vivo screening protocols as well as the lack of biomarkers for treating parasitaemia. The development of more effective drugs requires (i) the identification and validation of parasite targets, (ii) compounds to be screened against the targets or the whole parasite and (iii) a panel of minimum standardised procedures to advance leading compounds to clinical trials. This third aim was the topic of the workshop entitled Experimental Models in Drug Screening and Development for Chagas Disease, held in Rio de Janeiro, Brazil, on the 25th and 26th of November 2008 by the Fiocruz Program for Research and Technological Development on Chagas Disease and Drugs for Neglected Diseases Initiative. During the meeting, the minimum steps, requirements and decision gates for the determination of the efficacy of novel drugs for T. cruzi control were evaluated by interdisciplinary experts and an in vitro and in vivo flowchart was designed to serve as a general and standardised protocol for screening potential drugs for the treatment of Chagas disease.
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Affiliation(s)
- Alvaro José Romanha
- Programa Integrado de Doença de Chagas, Fiocruz, Rio de Janeiro, RJ, Brasil.
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Santos DM, Martins TA, Caldas IS, Diniz LF, Machado-Coelho GL, Carneiro CM, Oliveira RDP, Talvani A, Lana M, Bahia MT. Benznidazole alters the pattern of Cyclophosphamide-induced reactivation in experimental Trypanosoma cruzi-dependent lineage infection. Acta Trop 2010; 113:134-8. [PMID: 19854145 DOI: 10.1016/j.actatropica.2009.10.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 10/14/2009] [Accepted: 10/15/2009] [Indexed: 10/20/2022]
Abstract
The factors involved in the reactivation of chronic Chagas disease infection are not clear enough and may be related to host immune unbalance and/or parasite genetic diversity. To evaluate the role of the Trypanosoma cruzi genetic background in the Chagas disease reactivation, we inoculated Cyclophosphamide-immunosupressed (CyI) Swiss mice with clonal stocks from T. cruzi I (Cuica cl1, P209 cl1, Gamba cl1, SP104 cl1), T. cruzi II (IVV cl4, MVB cl8) and T. cruzi (Bug2148 cl1, MN cl2) lineages. We used the parasitemia as the parameter for Chagas disease reactivation and observed that CyI animals infected with T. cruzi stocks showed no reactivation and those infected with T. cruzi II stocks showed only 5% of reactivation. In contrast, immunosuppressed mice infected with stocks from T. cruzi I lineage showed 77.5 and 51.25% reactivation of the infection when Cyclophosphamide treatment was performed 60 and 180 days after inoculation, respectively. Next, we evaluated the efficacy of the Benznidazole (Bz) pre-treatment in reducing or preventing the recurrence of the infection in these CyI animals. In general, the percentage of the parasite recurrence was not altered among the CyI mice that received the Bz pre-treatment during the acute phase of the infection. Interestingly, when pre-Bz treatment was performed during the chronic phase, we observed two different patterns of response: (i) an increased protection among the animals inoculated with the SP104 cl1 (genotype 19) and Cuica cl1 (genotype 20) stocks; (ii) an increased percentage of parasitemia reactivation among mice inoculated with Gamba cl1 (genotype 19) and P209 cl1 (genotype 20) T. cruzi stocks. Our results corroborate our hypothesis by showing that the T. cruzi genetic background in combination with specific Bz treatment has an important role in the Chagas disease reactivation in immunosuppressed animals.
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Masumu J, Akoda K, Van den Bossche P. Transmissibility, by Glossina morsitans morsitans, of Trypanosoma congolense strains during the acute and chronic phases of infection. Acta Trop 2010; 113:195-8. [PMID: 19765543 DOI: 10.1016/j.actatropica.2009.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 08/31/2009] [Accepted: 09/08/2009] [Indexed: 10/20/2022]
Abstract
In order to verify whether chronic trypanosomal infections can affect the transmissibility of Trypanosoma congolense by tsetse flies, batches of Glossina morsitans morsitans were fed on mice infected with the same level of parasitemia (10(8.1)trypanosomes/ml of blood) of two cloned low virulent T. congolense strains during the acute and the chronic phases of infection. Results showed that the proportions of procyclic infections in flies that were fed during the acute phase (32.6% and 45.4% for isolates 1 and 2, respectively) were significantly higher (chi(2)=4.7, P<0.05 and chi(2)=23.7, P<0.0001, respectively) compared to the proportions of procyclic infections of flies fed during the chronic phase of infection (18.8% and 14.9% for isolates 1 and 2, respectively). Similarly the proportions of metacyclic infections in flies fed during the acute phase (32.6% and 45.4% for isolates 1 and 2, respectively) were significantly higher (chi(2)=6.3, P<0.05 and chi(2)=23.7, P<0.0001, respectively) compared to the proportions of metacyclic infections in flies fed during the chronic phase of infection (16.8% and 14.9% for isolates 1 and 2, respectively). No significant difference was found in the maturation rate of both strains during the acute phase compared to the chronic phase of infection (P>0.05). The results of this study suggest that T. congolense loses part of its transmissiblity by tsetse flies during the chronic phase of infection.
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Trypanosoma cruzi: in vitro activity of Epoxy-α-Lap, a derivative of α-lapachone, on trypomastigote and amastigote forms. Exp Parasitol 2009; 122:91-6. [DOI: 10.1016/j.exppara.2009.03.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2008] [Revised: 01/10/2009] [Accepted: 03/02/2009] [Indexed: 11/21/2022]
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Trypanosoma cruzi: Induction of benznidazole resistance in vivo and its modulation by in vitro culturing and mice infection. Exp Parasitol 2008; 120:385-90. [DOI: 10.1016/j.exppara.2008.09.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Revised: 08/14/2008] [Accepted: 09/08/2008] [Indexed: 11/21/2022]
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Boiani L, Aguirre G, González M, Cerecetto H, Chidichimo A, Cazzulo JJ, Bertinaria M, Guglielmo S. Furoxan-, alkylnitrate-derivatives and related compounds as anti-trypanosomatid agents: Mechanism of action studies. Bioorg Med Chem 2008; 16:7900-7. [DOI: 10.1016/j.bmc.2008.07.077] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 07/24/2008] [Accepted: 07/25/2008] [Indexed: 10/21/2022]
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Benznidazole therapy during acute phase of Chagas disease reduces parasite load but does not prevent chronic cardiac lesions. Parasitol Res 2008; 103:413-21. [DOI: 10.1007/s00436-008-0992-6] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Accepted: 04/04/2008] [Indexed: 11/26/2022]
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