Peptidylarginine Deiminase Inhibition Abolishes the Production of Large Extracellular Vesicles From

is a microaerophilic protozoan that is an important etiologic agent of diarrhea worldwide. There is evidence that under diverse conditions, the parasite is capable of shedding extracellular vesicles (EVs) which modulate the physiopathology of giardiasis. Here we describe new features of EV production, revealing its capacity to shed two different enriched EV populations: large (LEV) and small extracellular vesicles (SEV) and identified relevant adhesion functions associated with the larger population. Proteomic analysis revealed differences in proteins relevant for virulence and host-pathogen interactions between the two EV subsets, such as cytoskeletal and anti-oxidative stress response proteins in LEVS. We assessed the effect of two recently identified inhibitors of EV release in mammalian cells, namely peptidylarginine deiminase (PAD) inhibitor and cannabidiol (CBD), on EV release from . The compounds were both able to effectively reduce EV shedding, the PAD-inhibitor specifically affecting the release of LEVs and reducing parasite attachment to host cells . Our results suggest that LEVs and SEVs have a different role in host-pathogen interaction, and that treatment with EV-inhibitors may be a novel treatment strategy for recurrent giardiasis. [Abstract copyright: Copyright © 2020 Gavinho, Sabatke, Feijoli, Rossi, da Silva, Evans-Osses, Palmisano, Lange and Ramirez.

An induced population of Trypanosoma cruzi epimastigotes more resistant to complement lysis promotes a phenotype with greater differentiation, invasiveness, and release of extracellular vesicles

IntroductionChagas disease is a neglected tropical disease caused by Trypanosoma cruzi, which uses blood-feeding triatomine bugs as a vector to finally infect mammalian hosts. Upon entering the host, the parasite needs to effectively evade the attack of the complement system and quickly invade cells to guarantee an infection. In order to accomplish this, T. cruzi expresses different molecules on its surface and releases extracellular vesicles (EVs).MethodsHere, we have selected a population of epimastigotes (a replicative form) from T. cruzi through two rounds of exposure to normal human serum (NHS), to reach 30% survival (2R population). This 2R population was characterized in several aspects and compared to Wild type population.ResultsThe 2R population had a favored metacyclogenesis compared with wild-type (WT) parasites. 2R metacyclic trypomastigotes had a two-fold increase in resistance to complementmediated lysis and were at least three times more infective to eukaryotic cells, probably due to a higher GP82 expression in the resistant population. Moreover, we have shown that EVs from resistant parasites can transfer the invasive phenotype to the WT population. In addition, we showed that the virulence phenotype of the selected population remains in the trypomastigote form derived from cell culture, which is more infective and also has a higher rate of release of trypomastigotes from infected cells.ConclusionsAltogether, these data indicate that it is possible to select parasites after exposure to a particular stress factor and that the phenotype of epimastigotes remained in the infective stage. Importantly, EVs seem to be an important virulence fator increasing mechanism in this context of survival and persistence in the host

A correlação entre a ludicidade e os diferentes gêneros literários para aplicação nas séries iniciais da educação infantil

A educação infantil é um período que propicia à criança um mundo de descobertas, (re)significações culturais, comunicação, leitura de mundo e o consequente desenvolvimento omnilateral desses estudantes. A partir disso, somam-se estratégias de ensino: a ludicidade aliada aos conceitos de diferentes gêneros literários, de forma especial a contação de histórias, a poesia, a literatura de cordel e a literatura popular, como saberes a serem trabalhados em sala de aula. Com isso, esse estudo tem como objetivo descrever a correlação entre a ludicidade e os diferentes gêneros textuais trabalhados nas séries iniciais da educação infantil, respondendo à pergunta: qual é a correlação estabelecida entre os gêneros literários e a ludicidade? A metodologia utilizada para a pesquisa foi bibliográfica, com abordagem qualitativa, de natureza básica. Encontrou-se que a aplicação de diferentes gêneros literários, através da ludicidade, pode otimizar de forma divertida, leve e inovadora a criatividade, a imaginação, a lateralidade e a autonomia, potencialidades que estão em pleno desenvolvimento nas crianças. Palavras-chave: gêneros literários; ludicidade; educação infantil. Abstract Early childhood education is a period that provides children with a world of discoveries, cultural (re)meanings, communication, reading the world and the consequent omnilateral development of these students. From this, teaching strategies are added: playfulness combined with concepts from different literary genres, especially storytelling, poetry, cordel literature and popular literature, are the knowledge to be worked on the classroom. Therefore, this study aims to describe the correlation between playfulness and the different textual genres worked in the initial grades of early childhood education, answering the question: what is the correlation established between literary genres and playfulness? The methodology used for the research was bibliographic, with a qualitative approach, of a basic nature. It was found that approaching different literary genres through play, can optimize creativity, imagination, laterality and autonomy in a fun, light and innovative way, potentialities that are in full development in children. Keywords: literary genres; playfulness; child education. Resumen La educación infantil es un periodo que proporciona a niño un mundo de descubiertas, (re)significaciones culturales, comunicación, lectura de mundo y el consecuente desarrollo omnilateral de esos estudiantes. A partir de eso, se suman estrategias de enseñanza: lo lúdico junto a los conceptos de distintos géneros literarios, de forma especial la narración de historias, la poesía, la literatura de cordel y la literatura popular, como saberes a trabajar en aula. Con ello, ese estudio tiene como objetivo describir la correlación entre lo lúdico y los distintos géneros textuales trabajados en las series iniciales de la educación infantil, respondiendo a la pregunta: ¿cuál es la correlación establecida entre os géneros literarios y lo lúdico? Se empleó la metodología bibliográfica para la investigación, con enfoque cualitativo, de naturaleza básica. Se comprobó que la aplicación de distintos géneros literarios, mediante lo lúdico, puede maximizar, de forma divertida, leve e innovadora, la creatividad, la imaginación, la lateralidad y la autonomía, potencialidades que están en pleno desarrollo en los niños. Palabras clave: géneros literarios; lúdico; educación infantil

An induced population of Trypanosoma cruzi epimastigotes more resistant to complement lysis promotes a phenotype with greater differentiation, invasiveness, and release of extracellular vesicles

Chagas disease is a neglected tropical disease caused by , which uses blood-feeding triatomine bugs as a vector to finally infect mammalian hosts. Upon entering the host, the parasite needs to effectively evade the attack of the complement system and quickly invade cells to guarantee an infection. In order to accomplish this, expresses different molecules on its surface and releases extracellular vesicles (EVs). Here, we have selected a population of epimastigotes (a replicative form) from through two rounds of exposure to normal human serum (NHS), to reach 30% survival (2R population). This 2R population was characterized in several aspects and compared to Wild type population. The 2R population had a favored metacyclogenesis compared with wild-type (WT) parasites. 2R metacyclic trypomastigotes had a two-fold increase in resistance to complementmediated lysis and were at least three times more infective to eukaryotic cells, probably due to a higher GP82 expression in the resistant population. Moreover, we have shown that EVs from resistant parasites can transfer the invasive phenotype to the WT population. In addition, we showed that the virulence phenotype of the selected population remains in the trypomastigote form derived from cell culture, which is more infective and also has a higher rate of release of trypomastigotes from infected cells. Altogether, these data indicate that it is possible to select parasites after exposure to a particular stress factor and that the phenotype of epimastigotes remained in the infective stage. Importantly, EVs seem to be an important virulence fator increasing mechanism in this context of survival and persistence in the host

Synergistic Effect of Polysaccharides from Chamomile Tea with Nitazoxanide Increases Treatment Efficacy against Giardia intestinalis

Giardia intestinalis (syn. G. lamblia, G. duodenalis) is a protozoa parasite that produces one of the most frequent waterborne causes of diarrhea worldwide. This protozoan infects most mammals, including humans, and colonizes the small intestine, adhering to intestinal cells. The mechanism by which G. intestinalis causes diarrhea is multifactorial, causing intestinal malabsorption. The treatment of giardiasis uses chemotherapeutic drugs such as nitroimidazoles, furazolidone, paromomycin, and benzimidazole compounds. However, they are toxic, refractory, and may generate resistance. To increase efficacy, a current treatment strategy is to combine these drugs with other compounds, such as polysaccharides. Several studies have shown that polysaccharides have gastroprotective effects. Polysaccharides are high-molecular weight polymers, and they differ in structure and functions, being widely extracted from vegetables and fruits. In the present study, we show that polysaccharides found in chamomile tea (called MRW), in contact with antiparasitic agents, potentially inhibit the adhesion of parasites to intestinal cells. Moreover, at 500 µg/mL, they act synergistically with nitazoxanide (NTZ), increasing its effectiveness and decreasing the drug dose needed for giardiasis treatment

Avaliação do efeito dos polissacarídeos na interação in vitro entre os trofozoítos de Giardia intestinalis e drogas antiparasitárias

Orientador: Prof. Dr. Marcel Ivan Ramirez ArayaDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e Molecular. Defesa : Curitiba, 10/05/2021Inclui referências: p. 62-72Resumo: Giardia intestinalis (sin. G. lamblia ou G. duodenalis) é um protozoário anaeróbio flagelado eucariótico. O parasita produz uma das mais frequentes diarreia de veiculação hídrica em todo o mundo, a giardíase. Giardia possui um ciclo monogênico e duas formas evolutivas: cistos e trofozoítos. Esse protozoário infecta a maioria dos mamíferos, incluindo o homem. Quando infecta o hospedeiro coloniza o intestinal delgado, aderindose as células intestinais. O mecanismo pelo qual Giardia intestinalis causa diarreia e má absorção intestinal é multifatorial. No entanto os mecanismos da patogenicidade permanecem desconhecidos. O tratamento convencional da doença é realizado com metronidazol ou albendazol, porém esses medicamentos são tóxicos para o organismo e apresentam diversos efeitos colaterais. Além disso, vários estudos têm reportado casos de resistência dos parasitas. Uma estratégia de tratamento atual é combinar drogas com polímeros, macromoléculas ou polissacarídeos. Aqui testamos o efeito do polissacarídeo extraído da camomila a qual possui ação anti-inflamatória e é popularmente usada para distúrbios gastrointestinais. Apresentamos aqui dados sobre a suscetibilidade de G. intestinalis aos dois fármacos albendazol (ABZ) e nitazoxanida (NTZ) na presença de polissacarídeo extraído da camomila. Vimos que a combinação de 250 ?g de camomila com albendazol ou nitazoxanida tornou a ação do medicamento mais eficaz. Além disso, observamos que a combinação das drogas com o polissacarídeo impediu os parasitas de se recuperarem e reestabelecerem uma nova curva de crescimento, gerando a possibilidade de tratamentos mais eficazes e menos tóxicos do que os atuais.Abstract: Giardia intestinalis (syn. G. lamblia or G. duodenalis) anaerobic eukaryotic flagellate protozoan. The parasite produces one of the most frequent waterborne diarrhea in the world, giardiasis. Giardia has a monogenic cycle and two evolutionary forms: cysts and trophozoites. This protozoan infects most mammals, including man. When it infects the host, it colonizes the small intestinal, adhering to the intestinal cells. The mechanism by which Giardia intestinalis causes diarrhea and intestinal malabsorption is multifactorial. However, the mechanisms of pathogenicity remain unknown. Conventional treatment of the disease is performed with metronidazole or albendazole, but these drugs are toxic to the body and have several side effects. Furthermore, several studies have reported cases of parasite resistance. A current treatment strategy is to combine drugs with polymers, macromolecules, or polysaccharides. Here we test the effect of polysaccharides extracted from chamomile, which has anti-inflammatory action and is popularly used for gastrointestinal disorders. We present here data on the susceptibility of G. intestinalis to the two drugs albendazole (ABZ) and nitazoxanide (NTZ) in the presence of polysaccharides extracted from chamomile. We saw that the combination of 250 ?g of chamomile with albendazole or nitazoxanide made the drug's action more effective. Furthermore, we observed that the combination of the drugs with the polysaccharide prevented the parasites from recovering and re-establishing a new growth curve, generating the possibility of more effective and less toxic treatments than the current ones

Unveiling the role of EVs in anaerobic parasitic protozoa

The anaerobic or microaerophilic protozoan parasites such as the enteric human pathogens Entamoeba histolytica, Giardia intestinalis, Cryptosporidium parvum, Blastocystis hominis and urogenital tract parasites Trichomonas vaginalis are able to survival in an environment with oxygen deprivation. Despite living in hostile environments these pathogens adopted different strategies to survive within the hosts. Among them, the release of extracellular vesicles (EVs) has become an active endeavor in the study of pathogenesis for these parasites. EVs are heterogenous, membrane-limited structures that have played important roles in cellular communication, transferring information through cargo and modulating the immune system of the host. In this review, we described several aspects of the recently characterized EVs of the anaerobic protozoa, including their role in adhesion, modulation of the immune response and omics analysis to understand the potential of these EVs in the pathogenesis of these diseases caused by anaerobic parasites.Fil: Sabatke, Bruna. Universidade Federal do Paraná; BrasilFil: Gavinho, Bruno. Universidade Federal do Paraná; BrasilFil: Cóceres, Verónica Mabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: de Miguel, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Ramirez, Marcel I.. Universidade Federal do Paraná; Brasil. Fundación Oswaldo Cruz; Brasi

Synergistic Effect of Polysaccharides from Chamomile Tea with Nitazoxanide Increases Treatment Efficacy against <i>Giardia intestinalis</i>

Giardia intestinalis (syn. G. lamblia, G. duodenalis) is a protozoa parasite that produces one of the most frequent waterborne causes of diarrhea worldwide. This protozoan infects most mammals, including humans, and colonizes the small intestine, adhering to intestinal cells. The mechanism by which G. intestinalis causes diarrhea is multifactorial, causing intestinal malabsorption. The treatment of giardiasis uses chemotherapeutic drugs such as nitroimidazoles, furazolidone, paromomycin, and benzimidazole compounds. However, they are toxic, refractory, and may generate resistance. To increase efficacy, a current treatment strategy is to combine these drugs with other compounds, such as polysaccharides. Several studies have shown that polysaccharides have gastroprotective effects. Polysaccharides are high-molecular weight polymers, and they differ in structure and functions, being widely extracted from vegetables and fruits. In the present study, we show that polysaccharides found in chamomile tea (called MRW), in contact with antiparasitic agents, potentially inhibit the adhesion of parasites to intestinal cells. Moreover, at 500 µg/mL, they act synergistically with nitazoxanide (NTZ), increasing its effectiveness and decreasing the drug dose needed for giardiasis treatment

Trypanosoma cruzi interaction with host tissues modulate the composition of large extracellular vesicles

Abstract Trypanosoma cruzi is the protozoan that causes Chagas disease (CD), an endemic parasitosis in Latin America distributed around the globe. If CD is not treated in acute phase, the parasite remains silent for years in the host's tissues in a chronic form, which may progress to cardiac, digestive or neurological manifestations. Recently, studies indicated that the gastrointestinal tract represents an important reservoir for T. cruzi in the chronic phase. During interaction T. cruzi and host cells release extracellular vesicles (EVs) that modulates the immune system and infection, but the dynamics of secretion of host and parasite molecules through these EVs is not understood. Now, we used two cell lines: mouse myoblast cell line C2C12, and human intestinal epithelial cell line Caco-2to simulate the environments found by the parasite in the host. We isolated large EVs (LEVs) from the interaction of T. cruzi CL Brener and Dm28c/C2C12 and Caco-2 cells upon 2 and 24 h of infection. Our data showed that at two hours there is a strong cellular response mediated by EVs, both in the number, variety and enrichment/targeting of proteins found in LEVs for diverse functions. Qualitative and quantitative analysis showed that proteins exported in LEVs of C2C12 and Caco-2 have different patterns. We found a predominance of host proteins at early infection. The parasite-host cell interaction induces a switch in the functionality of proteins carried by LEVs and a heterogeneous response depending on the tissues analyzed. Protein–protein interaction analysis showed that cytoplasmic and mitochondrial homologues of the same parasite protein, tryparedoxin peroxidase, were differentially packaged in LEVs, also impacting the interacting molecule of this protein in the host. These data provide new evidence that the interaction with T. cruzi leads to a rapid tissue response through the release of LEVs, reflecting the enrichment of some proteins that could modulate the infection environment

An induced population of Trypanosoma cruzi epimastigotes more resistant to complement lysis promotes a phenotype with greater differentiation, invasiveness, and release of extracellular vesicles

© 2022 Rossi, Nunes, Sabatke, Ribas, Winnischofer, Ramos, Inal and Ramirez. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). https://creativecommons.org/licenses/by/4.0/Introduction: Chagas disease is a neglected tropical disease caused by Trypanosoma cruzi, which uses blood-feeding triatomine bugs as a vector to finally infect mammalian hosts. Upon entering the host, the parasite needs to effectively evade the attack of the complement system and quickly invade cells to guarantee an infection. In order to accomplish this, T. cruzi expresses different molecules on its surface and releases extracellular vesicles (EVs). Methods: Here, we have selected a population of epimastigotes (a replicative form) from T. cruzi through two rounds of exposure to normal human serum (NHS), to reach 30% survival (2R population). This 2R population was characterized in several aspects and compared to Wild type population. Results: The 2R population had a favored metacyclogenesis compared with wild-type (WT) parasites. 2R metacyclic trypomastigotes had a two-fold increase in resistance to complementmediated lysis and were at least three times more infective to eukaryotic cells, probably due to a higher GP82 expression in the resistant population. Moreover, we have shown that EVs from resistant parasites can transfer the invasive phenotype to the WT population. In addition, we showed that the virulence phenotype of the selected population remains in the trypomastigote form derived from cell culture, which is more infective and also has a higher rate of release of trypomastigotes from infected cells. Conclusions: Altogether, these data indicate that it is possible to select parasites after exposure to a particular stress factor and that the phenotype of epimastigotes remained in the infective stage. Importantly, EVs seem to be an important virulence fator increasing mechanism in this context of survival and persistence in the host.Peer reviewe