Retrospective study of triatomines in an endemic region for Chagas disease in the state of Bahia, Brazil / Estudo retrospectivo de triatomíneos em região endêmica para a doença de Chagas no estado da Bahia, Brasil

Chagas disease is caused by Trypanosoma cruzi, which has several forms of transmission. Among them, the vector route requires the constant action of the Health Surveillance in the control of triatomines. Our objective is to describe the diversity of triatomines and the rate of natural infection by T. cruzi in these insects, as well as to analyse entomological indicators, through secondary data generated by the Health Surveillance of the municipality of Barra, in the period from 2009 to 2019. The secondary data were subjected to descriptive analysis and the entomological indicators calculated. Williams' G test and Fisher's exact test were used to analyse the categorical data. A total of 10,913 triatomines of the genera Rhodnius sp., Panstrongylus sp., Eratyrus sp. and Triatoma sp. were captured, represented by 12 species. Triatoma sordida was the most prevalent 98.66% (10,767/10,913), reflected in the overall infestation index 7.61% (2,555/33,544) and triatomine density 0.24 (8,247/33,544). While the overall infection rate was 0.81% (41/5,048) and remained low during all years. There was significant association for T. sordida in relation to "T. cruzi infection index" and "Developmental stage" and "Capture site". It is concluded that the municipality of Barra has a high occurrence of triatomines of various species, with T. sordida being the most prevalent species and responsible for the rates of infestation and infection by T. cruzi. The presence of these insects in households is a risk for the domestic cycle of the parasite, and thus can transmit T. cruzi to various domestic animals, including humans.(AU)

doença de Chagas é causada pelo Trypanosoma cruzi, que possui diversas formas de transmissão. Dentre elas, a via vetorial, requer a atuação constante da Vigilância em Saúde no controle dos triatomíneos. Nosso objetivo é descrever a diversidade de triatomíneos e o índice de infecção natural por T. cruzi nestes insetos, bem como analisar os indicadores ento-mológicos, por meio de dados secundários gerados pela Vigilância em Saúde do município de Barra, no período de 2009 a 2019. Os dados secundários foram submetidos a análise descritiva e os indicadores entomológicos calculados. Os testes G de Williams e exato de Fisher foram utilizados para a análise dos dados categóricos. Foram capturados 10.913 triatomíneos, dos gêneros Rhodnius sp., Panstrongylus sp., Eratyrus sp. e Triatoma sp., representados por 12 espécies. Triatoma sordida foi a mais prevalente 98,66% (10.767/10.913), refletindo no índice de infestação geral 7,61% (2.555/33.544) e densidade triatomínea 0,24 (8.247/33.544). Enquanto que o índice de infecção geral foi de 0,81% (41/5.048) e manteve-se baixo durante todos os anos. Houve associação significativa para T. sordida em relação ao "Índice de infecção por T. cruzi" e "Estágio de desenvolvi-mento" e "Local de captura". Conclui-se que o município de Barra apresenta uma alta ocorrência de triatomíneos de diversas espécies, sendo T. sordida a espécie mais prevalente e responsável pelos índices de infestação e infecção por T. cruzi. A presença desses insetos nos domicílios é um risco para o ciclo doméstico do parasito, podendo assim transmitir o T. cruzi para diversos animais domésticos, inclusive humanos.(AU)

Molecular detection and phylogenetic analysis of Trypanosoma spp. in Neotropical primates from Rio de Janeiro State, Brazil / Detecção molecular e análise filogenética de Trypanosoma spp. em primatas neotropicais do estado do Rio de Janeiro, Brasil

Trypanosoma spp. infection is a problem in many tropical countries, infecting several animal species, including humans. The aim of the present study was to identify the Trypanosoma species in Neotropical primates from Rio de Janeiro state and compare the results with other reports both phylogenetically and geographically. Molecular detection was based on the 18 SSU gene. The sequences obtained in the PCR were sequenced and compared with others previously deposited in GenBank. These sequences were used to perform phylogenetic analysis and make a distribution map of primate species infected by Trypanosoma species in Brazil. Among 34 monkeys, five capuchin monkeys (Sapajus spp.) and one marmoset (Callithrix spp.) showed Trypanosoma spp. sequences in the same clade of Trypanosoma minasense and three capuchin monkeys' sequences were in the same clade of Trypanosoma cruzi. The Atlantic Forest and the Brazilian Amazon are the regions with the highest frequency of studies about Trypanosoma spp. and variety of Neotropical primate hosts. These are areas that deserve attention regarding the conservation of biodiversity, but it also makes evident the lack of studies with Neotropical primates in other regions of the country, as well as multidisciplinary studies to better understand the host pathogen relationships.

A infecção por Trypanosoma spp. é um problema em muitos países tropicais, infectando várias espécies animais, incluindo humanos. O objetivo do presente estudo foi identificar as espécies de Trypanosoma em primatas neotropicais no estado Rio de Janeiro e comparar os resultados com outros relatos, tanto filogeneticamente quando geograficamente. A detecção molecular foi baseada no gene SSU 18. As sequências obtidas na PCR foram sequenciadas e comparadas com outras previamente depositadas no GenBank. Essas sequências foram utilizadas para análises filogenéticas e confeccionar um mapa de distribuição de espécies de primatas infectadas por espécies de Trypanosoma no Brasil. Entre 34 macacos, cinco macacos-prego (Sapajus spp.) e um sagui (Callithrix spp.) apresentaram sequências de Trypanosoma spp. no mesmo clado de Trypanosoma minasense e três sequências de macacos-prego estavam no mesmo clado de Trypanosoma cruzi. A Mata Atlântica e a Amazônia brasileira são as regiões com maior frequência de estudos sobre Trypanosoma spp. e variedade de primatas neotropicais hospedeiros. São áreas que merecem atenção no que se refere à conservação da biodiversidade, mas também evidencia a carência de estudos com PNH em outras regiões do país e de estudos multidisciplinares para melhor compreender as relações do patógeno hospedeiro.

Validation of a documentary on Chagas disease by a population living in an endemic area / Validação de um documentário sobre a doença de Chagas por uma população de área endêmica

Educational interventions may trigger actions that contribute to prevent parasitic diseases, such as Chagas disease (CD). This study aimed at investigating the impact of an instructional video named Documentary on Chagas Disease on knowledge about CD and its vectors displayed by a population that lives in an endemic area in Brazil, so as to validate it as an educational tool. The video was shown to 226 subjects, divided into two groups. Group 1 was composed of users of Basic Health Units (BHU) in Pelotas and Pinheiro Machado, cities located in Rio Grande do Sul (RS) state, Brazil, where CD is endemic. Group 2 consisted of students who attend three public schools located in the rural area in Pinheiro Machado, RS. Two questionnaires with questions about their knowledge about triatomines and CD were applied, before and after the documentary was shown. After the video was shown, there was significant increase in individuals knowledge (in both groups) about kissing bugs, their notification, the disease and its prevention. Besides, watchers considered that the quality of the material was satisfactory. Since the Documentary on CD can be easily accessed on the internet and was effective in teaching the population that lives in endemic areas, its use should be encouraged in places and meetings connected to health that aim at fighting against triatominae and at exposing an updated view of CD.(AU)

Intervenções educacionais podem desencadear ações que contribuam para a prevenção de doenças parasitárias, como a doença de Chagas (DC). Este estudo teve como objetivo investigar o impacto de um vídeo instrucional denominado Documentário Doença de Chagas no conhecimento sobre DC e seus vetores exibidos a uma população que vive em área endêmica no Brasil, para validá-lo como uma ferramenta educacional. O vídeo foi exibido para 226 indivíduos, divididos em dois grupos. O grupo 1 foi composto por usuários das Unidades Básicas de Saúde (UBS) de Pelotas e Pinheiro Machado, cidades do estado do Rio Grande do Sul (RS), Brasil, onde a DC é endêmica. O grupo 2 foi formado por estudantes que frequentam três escolas públicas localizadas na zona rural de Pinheiro Machado, RS. Dois questionários com perguntas sobre conhecimentos sobre triatomíneos e DC foram aplicados, antes e depois da exibição do documentário. Após a exibição do vídeo, houve um aumento significativo no conhecimento dos indivíduos (em ambos os grupos) sobre triatomíneos, sua notificação, a doença e sua prevenção. Além disso, os observadores consideraram que a qualidade do material era satisfatória. Como o Documentário DC pode ser facilmente acessado na Internet e ser eficaz no ensino à população que vive em áreas endêmicas, seu uso deve ser incentivado em locais e reuniões relacionadas à saúde, que visam combater os triatomíneos e exibir uma informação atualizada sobre a DC.(AU)

Ocorrência de triatomíneos no Estado do Ceará, Brasil / Occurrence of triatomines in the state of Ceará, Brazil

Esta revisão integrativa tem como objetivo analisar as publicações científicas nos últimos doze anos sobre triatomíneos encontrados no Estado do Ceará. Para tal, nos bancos de dados da Biblioteca Virtual em Saúde (BVS) foi realizada uma busca com associação dos descritores “Doença de Chagas”, “Triatomíneos” e “Brasil”. Após aplicação dos critérios de inclusão, exclusão e da análise dos seus conteúdos, oito artigos realizados no Estado do Ceará foram selecionados para a análise do estudo. Algumas espécies de triatomíneos encontradas no Nordeste são de extrema importância epidemiológica para o homem, pois estão associadas com domicílios humanos. As espécies mais predominantes com maior importância epidemiológica, com distribuição ampla no Ceará e presente no ambiente peridoméstico foram: Triatoma brasiliensis, Triatoma pseudomaculata, Panstrogylus megistus, Panstrogylus lutzi e Rhodnius nasutus. Várias espécies de triatomíneos tem a capacidade de transmitir Trypanosoma cruzi e de se adaptar com o ambiente peridoméstico e doméstico tornando o homem mais suscetível a infecção, sendo assim necessário estratégias de vigilância e controle do vetor.

This integrative review aims to analyze the scientific publications in the last twelve years on triatomines found at Ceará State. For this, a search was performed in the Biblioteca Virtual em Saúde (BVS) databases with association of the descriptors “Chagas Disease”, “Triatomines” and “Brazil”. After applying the inclusion, exclusion criteria and analysis of their content, eight articles were selected for the analysis and discussion. Some species of triatomines found in the Northeast region are of extreme epidemiological importance since they are associated with human households. The most prevalent species with epidemiological importance due to their large distribution in Ceará and presence in the peridomestic environment are: Triatoma brasiliensis, Triatoma pseudomaculata, Panstrogylus megistus, Panstrogylus lutzi and Rhodnius nasutus. Several species of triatomines have the capacity to transmit T. cruzi and the ability to adapt to the peridomestic and domestic environment turning humans more susceptible to infection, thus requiring surveillance and vector control strategies.

Validation of a documentary on Chagas disease by a population living in an endemic area

Abstract Educational interventions may trigger actions that contribute to prevent parasitic diseases, such as Chagas disease (CD). This study aimed at investigating the impact of an instructional video named Documentary on Chagas Disease on knowledge about CD and its vectors displayed by a population that lives in an endemic area in Brazil, so as to validate it as an educational tool. The video was shown to 226 subjects, divided into two groups. Group 1 was composed of users of Basic Health Units (BHU) in Pelotas and Pinheiro Machado, cities located in Rio Grande do Sul (RS) state, Brazil, where CD is endemic. Group 2 consisted of students who attend three public schools located in the rural area in Pinheiro Machado, RS. Two questionnaires with questions about their knowledge about triatomines and CD were applied, before and after the documentary was shown. After the video was shown, there was significant increase in individuals knowledge (in both groups) about kissing bugs, their notification, the disease and its prevention. Besides, watchers considered that the quality of the material was satisfactory. Since the Documentary on CD can be easily accessed on the internet and was effective in teaching the population that lives in endemic areas, its use should be encouraged in places and meetings connected to health that aim at fighting against triatominae and at exposing an updated view of CD.

Resumo Intervenções educacionais podem desencadear ações que contribuam para a prevenção de doenças parasitárias, como a doença de Chagas (DC). Este estudo teve como objetivo investigar o impacto de um vídeo instrucional denominado Documentário Doença de Chagas no conhecimento sobre DC e seus vetores exibidos a uma população que vive em área endêmica no Brasil, para validá-lo como uma ferramenta educacional. O vídeo foi exibido para 226 indivíduos, divididos em dois grupos. O grupo 1 foi composto por usuários das Unidades Básicas de Saúde (UBS) de Pelotas e Pinheiro Machado, cidades do estado do Rio Grande do Sul (RS), Brasil, onde a DC é endêmica. O grupo 2 foi formado por estudantes que frequentam três escolas públicas localizadas na zona rural de Pinheiro Machado, RS. Dois questionários com perguntas sobre conhecimentos sobre triatomíneos e DC foram aplicados, antes e depois da exibição do documentário. Após a exibição do vídeo, houve um aumento significativo no conhecimento dos indivíduos (em ambos os grupos) sobre triatomíneos, sua notificação, a doença e sua prevenção. Além disso, os observadores consideraram que a qualidade do material era satisfatória. Como o Documentário DC pode ser facilmente acessado na Internet e ser eficaz no ensino à população que vive em áreas endêmicas, seu uso deve ser incentivado em locais e reuniões relacionadas à saúde, que visam combater os triatomíneos e exibir uma informação atualizada sobre a DC.

Ocorrência de triatomíneos no Estado do Ceará, Brasil / Occurrence of triatomines in the state of Ceará, Brazil

Esta revisão integrativa tem como objetivo analisar as publicações científicas nos últimos doze anos sobre triatomíneos encontrados no Estado do Ceará. Para tal, nos bancos de dados da Biblioteca Virtual em Saúde (BVS) foi realizada uma busca com associação dos descritores “Doença de Chagas”, “Triatomíneos” e “Brasil”. Após aplicação dos critérios de inclusão, exclusão e da análise dos seus conteúdos, oito artigos realizados no Estado do Ceará foram selecionados para a análise do estudo. Algumas espécies de triatomíneos encontradas no Nordeste são de extrema importância epidemiológica para o homem, pois estão associadas com domicílios humanos. As espécies mais predominantes com maior importância epidemiológica, com distribuição ampla no Ceará e presente no ambiente peridoméstico foram: Triatoma brasiliensis, Triatoma pseudomaculata, Panstrogylus megistus, Panstrogylus lutzi e Rhodnius nasutus. Várias espécies de triatomíneos tem a capacidade de transmitir Trypanosoma cruzi e de se adaptar com o ambiente peridoméstico e doméstico tornando o homem mais suscetível a infecção, sendo assim necessário estratégias de vigilância e controle do vetor.(AU)

This integrative review aims to analyze the scientific publications in the last twelve years on triatomines found at Ceará State. For this, a search was performed in the Biblioteca Virtual em Saúde (BVS) databases with association of the descriptors “Chagas Disease”, “Triatomines” and “Brazil”. After applying the inclusion, exclusion criteria and analysis of their content, eight articles were selected for the analysis and discussion. Some species of triatomines found in the Northeast region are of extreme epidemiological importance since they are associated with human households. The most prevalent species with epidemiological importance due to their large distribution in Ceará and presence in the peridomestic environment are: Triatoma brasiliensis, Triatoma pseudomaculata, Panstrogylus megistus, Panstrogylus lutzi and Rhodnius nasutus. Several species of triatomines have the capacity to transmit T. cruzi and the ability to adapt to the peridomestic and domestic environment turning humans more susceptible to infection, thus requiring surveillance and vector control strategies.(AU)

Using prodigiosin against some gram-positive and gram-negative bacteria and Trypanosoma cruzi

This work aimed to explore the action of natural prodigiosin on both bacterial organisms and Trypanosoma cruzi cells. Methods: Natural prodigiosin pigment was extracted and purified from cultures of Serratia marcescens. Two media, peanut broth and peptone glycerol broth, both recommended in the literature for prodigiosin production, were compared. The prodigiosin obtained was employed to explore its antimicrobial properties against both bacteria and Trypanosoma cruzi cells. Results: Peanut broth yielded four times more prodigiosin. The prodigiosin showed remarkable activity (minimal inhibitory concentrations in the range of 2-8 µM for bacteria and half maximal inhibitory concentration of 0.6 µM for Trypanosoma cruzi). In fact, the prodigiosin concentration required to inhibit parasite growth was as low as 0.25 mg/l versus 4.9 mg/l of benznidazole required. Furthermore, atomic force microscopy revealed marked morphological alterations in treated epimastigote forms, although no pore-formation activity was detected in protein-free environments. Conclusions: This work demonstrates the potential usefulness of prodigiosin against some gram-positive and gram-negative bacteria and Trypanosoma cruzi although further studies must be done in order to assess its value as a candidate molecule.(AU)

Using prodigiosin against some gram-positive and gram-negative bacteria and Trypanosoma cruzi

Background:This work aimed to explore the action of natural prodigiosin on both bacterial organisms and Trypanosoma cruzi cells.Methods:Natural prodigiosin pigment was extracted and purified from cultures of Serratia marcescens. Two media, peanut broth and peptone glycerol broth, both recommended in the literature for prodigiosin production, were compared. The prodigiosin obtained was employed to explore its antimicrobial properties against both bacteria and Trypanosoma cruzi cells.Results:Peanut broth yielded four times more prodigiosin. The prodigiosin showed remarkable activity (minimal inhibitory concentrations in the range of 2-8 µM for bacteria and half maximal inhibitory concentration of 0.6 µM for Trypanosoma cruzi). In fact, the prodigiosin concentration required to inhibit parasite growth was as low as 0.25 mg/l versus 4.9 mg/l of benznidazole required. Furthermore, atomic force microscopy revealed marked morphological alterations in treated epimastigote forms, although no pore-formation activity was detected in protein-free environments.Conclusions:This work demonstrates the potential usefulness of prodigiosin against some gram-positive and gram-negative bacteria and Trypanosoma cruzi although further studies must be done in order to assess its value as a candidate molecule.(AU)

Morphobiological, morphometric and ultrastructural characterization of sylvatic Trypanosoma cruzi isolates from Rio de Janeiro state, Brazil / Caracterização morfobiológica, morfométrica e ultraestrutural de isolados silvestres de Trypanosoma cruzi do estado do Rio de Janeiro, Brasil

Triatoma vitticeps is a triatomine with geographic distribution restrict to Brazil, which exhibits high prevalence of Trypanosoma cruzi natural infection. Of special epidemiologic concern, this species often invades households in the states of Rio de Janeiro, Minas Gerais and Espírito Santo. The objective of this study was to evaluate morphological and ultrastructural parameters on three T. cruzi isolates obtained from wild T. vitticeps specimens. The growth and cell differentiation of the parasite was evaluated through epimastigote and trypomastigote forms obtained in the growth curves for three distinct isolates. The maximum growth showed differences at the 20th day of the curve. Our in vitro results show a heterogeneity, regarding these features for samples cultivated under the same conditions. Morphometric analyzes based on the shape of epimastigotes and trypomastigotes corroborated such differentiation. These results highlight the need of better understanding the meaning of this diversity under an eco-epidemiological perspective.(AU)

Triatoma vitticeps é um triatomíneo com distribuição geográfica restrita ao território brasileiro, apresentando alta prevalência de infecção natural pelo Trypanosoma cruzi. Esta espécie é relevante sob o ponto de vista epidemiológico por invadir domicílios com frequência nos estados do Rio de Janeiro, Minas Gerais e Espírito Santo. O objetivo deste estudo foi avaliar parâmetros morfológicos e ultraestruturais, em três isolados de T. cruzi obtidos a partir de triatomíneos silvestres. O crescimento e a diferenciação celular do parasita foi avaliado através das formas epimastigotas e tripomastigotas obtidas nas curvas de crescimento para os três isolados. O crescimento máximo mostrou diferenças no 20º dia da curva. Nossos resultados in vitro mostram uma heterogeneidade, em relação a essas características para amostras cultivadas nas mesmas condições. As análises morfométricas baseadas na conformação de epimastigotas e trypomastigotes corroboraram essa diferenciação. Estes resultados ressaltam a necessidade de uma melhor compreensão do significado desta diversidade sob uma perspectiva eco-epidemiológica.(AU)

Impact of autologous whole blood administration upon experimental mouse models of acute Trypanosoma cruzi infection

Background: Autologous whole blood (AWB) administration is described as alternative/complementary medical practice widely employed in medical and veterinary therapy against infections, chronic pathologies and neoplasias. Our aim is to investigate in vivo biological effect of AWB using healthy murine models under the course of Trypanosoma cruzi acute infection. Methods: The first set of studies consisted of injecting different volumes of AWB and saline (SAL) into the posterior region of quadriceps muscle of healthy male Swiss mice under distinct therapeutic schemes evaluating: animal behavior, body and organ weight, hemogram, plasmatic biochemical markers for tissue damage and inflammatory cytokine levels and profile. To assess the impact on the experimental T. cruzi infection, different schemes (prior and post infection) and periods of AWB administration (from one up to 10 days) were conducted, also employing heterologous whole blood (HWB) and evaluating plasma cytokine profile. Results: No major adverse events were observed in healthy AWB-treated mice, except gait impairment in animals that received three doses of 20 L AWB in the same hind limb. AWB and SAL triggered an immediate polymorphonuclear response followed by mononuclear infiltrate. Although SAL triggered an inflammatory response, the kinetics and intensity of the histological profile and humoral mediator levels were different from AWB, the latter occurring earlier and more intensely with concomitant elevation of plasma IL-6. Inflammatory peak response of SAL, mainly composed of mononuclear cells with IL-10, was increased at 24 h. According to the mouse model of acute T. cruzi infection, only minor decreases ( 30%) in the parasitemia levels were produced by AWB and HWB given before and after infection, without protecting against mortality. Rises in IFN-gamma, TNF-alpha and...(AU)

Impact of autologous whole blood administration upon experimental mouse models of acute Trypanosoma cruzi infection

Background: Autologous whole blood (AWB) administration is described as alternative/complementary medical practice widely employed in medical and veterinary therapy against infections, chronic pathologies and neoplasias. Our aim is to investigate in vivo biological effect of AWB using healthy murine models under the course of Trypanosoma cruzi acute infection. Methods: The first set of studies consisted of injecting different volumes of AWB and saline (SAL) into the posterior region of quadriceps muscle of healthy male Swiss mice under distinct therapeutic schemes evaluating: animal behavior, body and organ weight, hemogram, plasmatic biochemical markers for tissue damage and inflammatory cytokine levels and profile. To assess the impact on the experimental T. cruzi infection, different schemes (prior and post infection) and periods of AWB administration (from one up to 10 days) were conducted, also employing heterologous whole blood (HWB) and evaluating plasma cytokine profile. Results: No major adverse events were observed in healthy AWB-treated mice, except gait impairment in animals that received three doses of 20 L AWB in the same hind limb. AWB and SAL triggered an immediate polymorphonuclear response followed by mononuclear infiltrate. Although SAL triggered an inflammatory response, the kinetics and intensity of the histological profile and humoral mediator levels were different from AWB, the latter occurring earlier and more intensely with concomitant elevation of plasma IL-6. Inflammatory peak response of SAL, mainly composed of mononuclear cells with IL-10, was increased at 24 h. According to the mouse model of acute T. cruzi infection, only minor decreases ( 30%) in the parasitemia levels were produced by AWB and HWB given before and after infection, without protecting against mortality. Rises in IFN-gamma, TNF-alpha and...

Efficacy of sertraline against Trypanosoma cruzi: an in vitro and in silico study

Background: Drug repurposing has been an interesting and cost-effective approach, especially for neglected diseases, such as Chagas disease. Methods: In this work, we studied the activity of the antidepressant drug sertraline against Trypanosoma cruzi trypomastigotes and intracellular amastigotes of the Y and Tulahuen strains, and investigated its action mode using cell biology and in silico approaches. Results: Sertraline demonstrated in vitro efficacy against intracellular amastigotes of both T. cruzi strains inside different host cells, including cardiomyocytes, with IC50 values between 1 to 10 M, and activity against bloodstream trypomastigotes, with IC50 of 14 M. Considering the mammalian cytotoxicity, the drug resulted in a selectivity index of 17.8. Sertraline induced a change in the mitochondrial integrity of T. cruzi, resulting in a decrease in ATP levels, but not affecting reactive oxygen levels or plasma membrane permeability. In silico approaches using chemogenomic target fishing, homology modeling and molecular docking suggested the enzyme isocitrate dehydrogenase 2 of T. cruzi (TcIDH2) as a potential target for sertraline. Conclusions: The present study demonstrated that sertraline had a lethal effect on different forms and strains of T. cruzi, by affecting the bioenergetic metabolism of the parasite. These findings provide a starting point for future experimental assays and may contribute to the development of new compounds.(AU)

Efficacy of sertraline against Trypanosoma cruzi: an in vitro and in silico study

Drug repurposing has been an interesting and cost-effective approach, especially for neglected diseases, such as Chagas disease. Methods: In this work, we studied the activity of the antidepressant drug sertraline against Trypanosoma cruzi trypomastigotes and intracellular amastigotes of the Y and Tulahuen strains, and investigated its action mode using cell biology and in silico approaches. Results: Sertraline demonstrated in vitro efficacy against intracellular amastigotes of both T. cruzi strains inside different host cells, including cardiomyocytes, with IC50 values between 1 to 10 µM, and activity against bloodstream trypomastigotes, with IC50 of 14 µM. Considering the mammalian cytotoxicity, the drug resulted in a selectivity index of 17.8. Sertraline induced a change in the mitochondrial integrity of T. cruzi, resulting in a decrease in ATP levels, but not affecting reactive oxygen levels or plasma membrane permeability. In silico approaches using chemogenomic target fishing, homology modeling and molecular docking suggested the enzyme isocitrate dehydrogenase 2 of T. cruzi (TcIDH2) as a potential target for sertraline. Conclusions: The present study demonstrated that sertraline had a lethal effect on different forms and strains of T. cruzi, by affecting the bioenergetic metabolism of the parasite. These findings provide a starting point for future experimental assays and may contribute to the development of new compounds.(AU)

Morphobiological, morphometric and ultrastructural characterization of sylvatic Trypanosoma cruzi isolates from Rio de Janeiro state, Brazil

Abstract Triatoma vitticeps is a triatomine with geographic distribution restrict to Brazil, which exhibits high prevalence of Trypanosoma cruzi natural infection. Of special epidemiologic concern, this species often invades households in the states of Rio de Janeiro, Minas Gerais and Espírito Santo. The objective of this study was to evaluate morphological and ultrastructural parameters on three T. cruzi isolates obtained from wild T. vitticeps specimens. The growth and cell differentiation of the parasite was evaluated through epimastigote and trypomastigote forms obtained in the growth curves for three distinct isolates. The maximum growth showed differences at the 20th day of the curve. Our in vitro results show a heterogeneity, regarding these features for samples cultivated under the same conditions. Morphometric analyzes based on the shape of epimastigotes and trypomastigotes corroborated such differentiation. These results highlight the need of better understanding the meaning of this diversity under an eco-epidemiological perspective.

Resumo Triatoma vitticeps é um triatomíneo com distribuição geográfica restrita ao território brasileiro, apresentando alta prevalência de infecção natural pelo Trypanosoma cruzi. Esta espécie é relevante sob o ponto de vista epidemiológico por invadir domicílios com frequência nos estados do Rio de Janeiro, Minas Gerais e Espírito Santo. O objetivo deste estudo foi avaliar parâmetros morfológicos e ultraestruturais, em três isolados de T. cruzi obtidos a partir de triatomíneos silvestres. O crescimento e a diferenciação celular do parasita foi avaliado através das formas epimastigotas e tripomastigotas obtidas nas curvas de crescimento para os três isolados. O crescimento máximo mostrou diferenças no 20º dia da curva. Nossos resultados in vitro mostram uma heterogeneidade, em relação a essas características para amostras cultivadas nas mesmas condições. As análises morfométricas baseadas na conformação de epimastigotas e trypomastigotes corroboraram essa diferenciação. Estes resultados ressaltam a necessidade de uma melhor compreensão do significado desta diversidade sob uma perspectiva eco-epidemiológica.

Antibodies anti-trypanosomatides in domestic cats in Paraná: who is at highest risk of infection? / Anticorpos anti-tripanossomatídeos em gatos domésticos no Paraná: quem está em maior risco de infecção?

The aim of this study were to detect antibodies anti-Leishmania spp. and anti-Trypanosoma cruzi in two different populations of domestic cats (Felis catus domesticus) from North Paraná referred for surgical castration and to determine which characteristics of the animals studied may be associated with seropositivity. Serum samples from 679 cats were analyzed using enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence antibody test (IFAT) in series. Associations between age, sex, race, year of care and animal group were verified using the simple logistic regression. Percentage of 8.5% (58/679) of cats were positive for Leishmania spp. and 7.6% (51/673) for T. cruzi by the tests ELISA and IFAT. Animals collected by non-governmental animal protection organizations presented more seropositivity for Leishmania spp. (p 0.0001). Results shown that Leishmania spp. and T. cruzi are present in domestic cats in the northern part of the state of Paraná, as well as, owners of non-governmental animal protection organizations may be more exposed to leishmaniasis when compared to other animal owners evaluated in the present study.(AU)

O objetivo desse estudo foi detectar a presença de anticorpos IgG anti-Leishmania spp. e anti-Trypanosoma cruzi em duas populações de gatos domésticos (Felis catus domesticus) do Norte do Paraná encaminhados para castração cirúrgica e determinar quais as características dos animais estudados que podem estar associadas à soropositividade. Amostras de soro de 679 gatos foram analisadas utilizando-se os testes imunoenzimático (ELISA) e a reação de imunofluorescência indireta (RIFI), em série. Associações entre idade, sexo, raça, ano de atendimento e grupo animal foram verificadas usando regressão logística simples. Um percentual de 8,5% (58/679) dos gatos apresentou positividade para Leishmania spp. e 7,6% (51/673) para T. cruzi pelos testes ELISA e RIFI. Gatos mantidos em organizações não governamentais de proteção animal apresentaram maior sororeatividade para Leishmania spp. (p 0.0001). As sorologias reativas para Leishmania spp. e Trypanosoma cruzi mostram que esses agentes estão presentes em gatos domésticos na parte norte do estado do Paraná, bem como, os proprietários de organizações não governamentais de proteção animal podem estar mais expostos à leishmaniose quando comparados com outros proprietários de animais avaliados no presente estudo.(AU)

Validation of a documentary on Chagas disease by a population living in an endemic area

Abstract Educational interventions may trigger actions that contribute to prevent parasitic diseases, such as Chagas disease (CD). This study aimed at investigating the impact of an instructional video named Documentary on Chagas Disease on knowledge about CD and its vectors displayed by a population that lives in an endemic area in Brazil, so as to validate it as an educational tool. The video was shown to 226 subjects, divided into two groups. Group 1 was composed of users of Basic Health Units (BHU) in Pelotas and Pinheiro Machado, cities located in Rio Grande do Sul (RS) state, Brazil, where CD is endemic. Group 2 consisted of students who attend three public schools located in the rural area in Pinheiro Machado, RS. Two questionnaires with questions about their knowledge about triatomines and CD were applied, before and after the documentary was shown. After the video was shown, there was significant increase in individuals knowledge (in both groups) about kissing bugs, their notification, the disease and its prevention. Besides, watchers considered that the quality of the material was satisfactory. Since the Documentary on CD can be easily accessed on the internet and was effective in teaching the population that lives in endemic areas, its use should be encouraged in places and meetings connected to health that aim at fighting against triatominae and at exposing an updated view of CD.

Resumo Intervenções educacionais podem desencadear ações que contribuam para a prevenção de doenças parasitárias, como a doença de Chagas (DC). Este estudo teve como objetivo investigar o impacto de um vídeo instrucional denominado Documentário Doença de Chagas no conhecimento sobre DC e seus vetores exibidos a uma população que vive em área endêmica no Brasil, para validá-lo como uma ferramenta educacional. O vídeo foi exibido para 226 indivíduos, divididos em dois grupos. O grupo 1 foi composto por usuários das Unidades Básicas de Saúde (UBS) de Pelotas e Pinheiro Machado, cidades do estado do Rio Grande do Sul (RS), Brasil, onde a DC é endêmica. O grupo 2 foi formado por estudantes que frequentam três escolas públicas localizadas na zona rural de Pinheiro Machado, RS. Dois questionários com perguntas sobre conhecimentos sobre triatomíneos e DC foram aplicados, antes e depois da exibição do documentário. Após a exibição do vídeo, houve um aumento significativo no conhecimento dos indivíduos (em ambos os grupos) sobre triatomíneos, sua notificação, a doença e sua prevenção. Além disso, os observadores consideraram que a qualidade do material era satisfatória. Como o Documentário DC pode ser facilmente acessado na Internet e ser eficaz no ensino à população que vive em áreas endêmicas, seu uso deve ser incentivado em locais e reuniões relacionadas à saúde, que visam combater os triatomíneos e exibir uma informação atualizada sobre a DC.

Benznidazole affects expression of Th1, Th17 and Treg cytokines during acute experimental Trypanosoma cruzi infection

Background The present study evaluated the effect of treatment with benznidazole on mRNA expression of IFN-γ, IL-17, IL-10, TGF-β and FoxP3 in spleen and heart tissue of BALB/c mice in the acute phase of an experimental infection with Trypanosoma cruzi, strains JLP or Y. Methods The mRNA expression of cytokines and parasite load were assessed by q-PCR. Dependent groups were compared using Student's paired t-test and independent groups were compared using Student's unpaired t-test. Results Infection with the JLP or Y strains increased expression of IFN-γ in the heart and of IL-10 and IL-17 in the spleen and heart compared to uninfected animals. Treatment increased the expression of IFN-γ and decreased the expression of IL-17, IL-10, TGF- β and Foxp3 in spleen and heart tissue compared to untreated infected animals. Conclusion Benznidazole can induce Th1 profile in the initial of the acute phase. The treatment decreased the parasite load in both organs, although the number of parasites in Y-strain-infected mice remained high. The data suggest that benznidazole may modulate cytokine expression in infection and can be dependent of the strain. However, treatment was not fully effective in the infection provoked by Y strain, probably due to the characteristics of the strain itself.(AU)

Ergosterol isolated from the basidiomycete Pleurotus salmoneostramineus affects Trypanosoma cruzi plasma membrane and mitochondria

Background Major drawbacks of the available treatment against Chagas disease (American trypanosomiasis) include its toxicity and therapeutic inefficiency in the chronic phase of the infection, which makes it a concern among neglected diseases. Therefore, the discovery of alternative drugs for treating chronic Chagas disease requires immediate action. In this work, we evaluated the mushroom Pleurotus salmoneostramineus in the search for potential antiparasitic compounds. Methods Fruit bodies of the basidiomycete Pleurotus salmoneostramineus were triturated and submitted to organic solvent extraction. After liquid-liquid partition of the crude extract, three fractions were obtained and the bioguided fractionation study was conducted to isolate the active metabolites. The elucidation of the chemical structure was performed using GC-MS and NMR techniques. The biological assays for antiparasitic activity were carried out using trypomastigotes of Trypanosoma cruzi and murine macrophages for mammalian cytotoxicity. The mechanism of action of the isolated compound used different fluorescent probes to evaluate the plasma membrane permeability, the potential of the mitochondrial membrane and the intracellular levels of reactive oxygen species (ROS). Results The most abundant fraction showing the antiparasitic activity was isolated and chemically elucidated, confirming the presence of ergosterol. It showed anti-Trypanosoma cruzi activity against trypomastigotes, with an IC50 value of 51.3 μg/mL. The compound demonstrated no cytotoxicity against mammalian cells to the maximal tested concentration of 200 μg/mL. The mechanism of action of ergosterol in Trypanosoma cruzi trypomastigotes resulted in permeabilization of the plasma membrane, as well as depolarization of mitochondrial membrane potential, leading to parasite death. Nevertheless, no increase in ROS levels could be observed, suggesting damages to plasma membrane rather than an induction of oxidative stress in the parasite. Conclusions The selection of naturally antiparasitic secondary metabolites in basidiomycetes, such as ergosterol, may provide potential scaffolds for drug design studies against neglected diseases.(AU)

Ergosterol isolated from the basidiomycete Pleurotus salmoneostramineus affects Trypanosoma cruzi plasma membrane and mitochondria

Background Major drawbacks of the available treatment against Chagas disease (American trypanosomiasis) include its toxicity and therapeutic inefficiency in the chronic phase of the infection, which makes it a concern among neglected diseases. Therefore, the discovery of alternative drugs for treating chronic Chagas disease requires immediate action. In this work, we evaluated the mushroom Pleurotus salmoneostramineus in the search for potential antiparasitic compounds. Methods Fruit bodies of the basidiomycete Pleurotus salmoneostramineus were triturated and submitted to organic solvent extraction. After liquid-liquid partition of the crude extract, three fractions were obtained and the bioguided fractionation study was conducted to isolate the active metabolites. The elucidation of the chemical structure was performed using GC-MS and NMR techniques. The biological assays for antiparasitic activity were carried out using trypomastigotes of Trypanosoma cruzi and murine macrophages for mammalian cytotoxicity. The mechanism of action of the isolated compound used different fluorescent probes to evaluate the plasma membrane permeability, the potential of the mitochondrial membrane and the intracellular levels of reactive oxygen species (ROS). Results The most abundant fraction showing the antiparasitic activity was isolated and chemically elucidated, confirming the presence of ergosterol. It showed anti-Trypanosoma cruzi activity against trypomastigotes, with an IC50 value of 51.3 μg/mL. The compound demonstrated no cytotoxicity against mammalian cells to the maximal tested concentration of 200 μg/mL. The mechanism of action of ergosterol in Trypanosoma cruzi trypomastigotes resulted in permeabilization of the plasma membrane, as well as depolarization of mitochondrial membrane potential, leading to parasite death. Nevertheless, no increase in ROS levels could be observed, suggesting damages to plasma membrane rather than an induction of oxidative stress in the parasite. Conclusions The selection of naturally antiparasitic secondary metabolites in basidiomycetes, such as ergosterol, may provide potential scaffolds for drug design studies against neglected diseases.(AU)

Benznidazole affects expression of Th1, Th17 and Treg cytokines during acute experimental Trypanosoma cruzi infection

Background The present study evaluated the effect of treatment with benznidazole on mRNA expression of IFN-γ, IL-17, IL-10, TGF-β and FoxP3 in spleen and heart tissue of BALB/c mice in the acute phase of an experimental infection with Trypanosoma cruzi, strains JLP or Y. Methods The mRNA expression of cytokines and parasite load were assessed by q-PCR. Dependent groups were compared using Student's paired t-test and independent groups were compared using Student's unpaired t-test. Results Infection with the JLP or Y strains increased expression of IFN-γ in the heart and of IL-10 and IL-17 in the spleen and heart compared to uninfected animals. Treatment increased the expression of IFN-γ and decreased the expression of IL-17, IL-10, TGF- β and Foxp3 in spleen and heart tissue compared to untreated infected animals. Conclusion Benznidazole can induce Th1 profile in the initial of the acute phase. The treatment decreased the parasite load in both organs, although the number of parasites in Y-strain-infected mice remained high. The data suggest that benznidazole may modulate cytokine expression in infection and can be dependent of the strain. However, treatment was not fully effective in the infection provoked by Y strain, probably due to the characteristics of the strain itself.(AU)