The repositioned drugs disulfiram/diethyldithiocarbamate combined to benznidazole: Searching for Chagas disease selective therapy, preventing toxicity and drug resistance

Chagas disease (CD) affects at least 6 million people in 21 South American countries besides several thousand in other nations all over the world. It is estimated that at least 14,000 people die every year of CD. Since vaccines are not available, chemotherapy remains of pivotal relevance. About 30% of the treated patients cannot complete the therapy because of severe adverse reactions. Thus, the search for novel drugs is required. Here we tested the benznidazole (BZ) combination with the repositioned drug disulfiram (DSF) and its derivative diethyldithiocarbamate (DETC) upon Trypanosoma cruzi in vitro and in vivo. DETC-BZ combination was synergistic diminishing epimastigote proliferation and enhancing selective indexes up to over 10-fold. DETC was effective upon amastigotes of the BZ- partially resistant Y and the BZ-resistant Colombiana strains. The combination reduced proliferation even using low concentrations (e.g., 2.5 µM). Scanning electron microscopy revealed membrane discontinuities and cell body volume reduction. Transmission electron microscopy revealed remarkable enlargement of endoplasmic reticulum cisternae besides, dilated mitochondria with decreased electron density and disorganized kinetoplast DNA. At advanced stages, the cytoplasm vacuolation apparently impaired compartmentation. The fluorescent probe H2-DCFDA indicates the increased production of reactive oxygen species associated with enhanced lipid peroxidation in parasites incubated with DETC. The biochemical measurement indicates the downmodulation of thiol expression. DETC inhibited superoxide dismutase activity on parasites was more pronounced than in infected mice. In order to approach the DETC effects on intracellular infection, peritoneal macrophages were infected with Colombiana trypomastigotes. DETC addition diminished parasite numbers and the DETC-BZ combination was effective, despite the low concentrations used. In the murine infection, the combination significantly enhanced animal survival, decreasing parasitemia over BZ. Histopathology revealed that low doses of BZ-treated animals presented myocardial amastigote, not observed in combination-treated animals. The picrosirius collagen staining showed reduced myocardial fibrosis. Aminotransferase de aspartate, Aminotransferase de alanine, Creatine kinase, and urea plasma levels demonstrated that the combination was non-toxic. As DSF and DETC can reduce the toxicity of other drugs and resistance phenotypes, such a combination may be safe and effective

Enteroparasitosis in Public Schools in Bahia: Parasitology Learning

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2018-06-08T12:40:32Z No. of bitstreams: 1 Fontes AMS Enteroparasitoses...pdf: 573458 bytes, checksum: 1130750bfb57df7a7934f89923aff125 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2018-06-08T12:47:14Z (GMT) No. of bitstreams: 1 Fontes AMS Enteroparasitoses...pdf: 573458 bytes, checksum: 1130750bfb57df7a7934f89923aff125 (MD5)Made available in DSpace on 2018-06-08T12:47:14Z (GMT). No. of bitstreams: 1 Fontes AMS Enteroparasitoses...pdf: 573458 bytes, checksum: 1130750bfb57df7a7934f89923aff125 (MD5) Previous issue date: 2017CNPq, Capes, FAPESB, INCT and PRONEXFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilParasitic diseases hamper progress in underdeveloped nations, compromising child physical and cognitive development. In order to control intestinal parasites, the popularization of science may enable prophylactic measures. Questionnaires were used to assess the students’ knowledge, attitudes and practices. Health fairs were held as an educational tool and subsequently questionnaires on parasitic diseases and prevention were administered. Stool examinations were performed and infected students were treated. Prevalence of Entamoeba histolytica/ dispar, Ascaris lumbricoides, Trichuris trichiura was 7.1%, 5% and 3.5% respectively in the Anísio Teixeira Institute students and 7.2%, 8%, 3.6% in the Raymundo Matta School students in a suburb. The students at both schools displayed limited knowledge on parasitic disease prevention. The school participation in the prophylaxis of parasitic diseases, was not acknowledged by the students. Reviewing curricula is required, addressing themes related to health, possibly establishing partnerships with health services, universities and/or research centers with the effective involvement of the community performing articulated actions in different health districts, so that education will lead to community empowerment in regard to quotidian issues and improving public health conditions

Role of Polyamines in Parasite Cell Architecture and Function

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2018-05-30T16:24:43Z No. of bitstreams: 1 Santos MAV Role of polyamine....pdf: 5363930 bytes, checksum: 4eb56499ef9056fa0a37582a44752a58 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2018-05-30T16:32:25Z (GMT) No. of bitstreams: 1 Santos MAV Role of polyamine....pdf: 5363930 bytes, checksum: 4eb56499ef9056fa0a37582a44752a58 (MD5)Made available in DSpace on 2018-05-30T16:32:25Z (GMT). No. of bitstreams: 1 Santos MAV Role of polyamine....pdf: 5363930 bytes, checksum: 4eb56499ef9056fa0a37582a44752a58 (MD5) Previous issue date: 2017FAPESB, PROEP/CNPq, PP-SUS and CAPES. MAVS is a CNPq research fellowFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Toxoplasmose e outras Protozooses. Rio de Janeiro RJ, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Laboratório de Toxoplasmose e outras Protozooses. Rio de Janeiro RJ, BrasilIn the absence of accessible, effective vaccines, the fight against parasitic disease relies mostly on chemotherapy. Nevertheless, the considerable side effects, high costs and growing number of refractory cases comprise substantial drawbacks. Thus, the search for new antiparasitic compounds remains a high priority. The polyamine biosynthesis, conversion and transport pathways offer different targets for selective chemotherapy. Polyamine analogues and other antagonists may provide tools in the search for new lead compounds. Light and electron microscopy techniques may encompass valuable approaches to elucidate the possible mechanisms of action of different antiparasitic compounds, allowing the identification of subcellular target compartments, presumably establishing the basis for a more rational drug design and/or planning of therapeutic strategies

Effects of a novel β-lapachone derivative on Trypanosoma cruzi: Parasite death involving apoptosis, autophagy and necrosis

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2017-03-16T17:23:37Z No. of bitstreams: 1 Anjos, DO Effect of a novel-B.pdf: 2604687 bytes, checksum: a792de2bdfe64e9fd85f69eada3276f8 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2017-03-16T17:40:58Z (GMT) No. of bitstreams: 1 Anjos, DO Effect of a novel-B.pdf: 2604687 bytes, checksum: a792de2bdfe64e9fd85f69eada3276f8 (MD5)Made available in DSpace on 2017-03-16T17:40:58Z (GMT). No. of bitstreams: 1 Anjos, DO Effect of a novel-B.pdf: 2604687 bytes, checksum: a792de2bdfe64e9fd85f69eada3276f8 (MD5) Previous issue date: 2016-12CNPq, PROCAD/Capes PP-SUS, PROEP, INCTINPeTAm, FAPESB, PRONEX/MCT.Fundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, Brasil / Universidade Estadual de Santa Cruz UESC. Departamento de Ciências Biológicas. Ilhéus, BA, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilUniversidade Federal Rural do Rio de Janeiro. UFRRJ. Instituto de Química. Rio de Janeiro, RJ, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilUniversidade Federal Rural do Rio de Janeiro. UFRRJ. Instituto de Química. Rio de Janeiro, RJ, BrasilUniversidade Federal de Mato Grosso. UFMT. Faculdade de Medicina. Cuiabá, MG, BrasilFundação Oswaldo Cruz. Instituto Gonçalo Moniz. Laboratório de Biologia Parasitária. Salvador, BA, BrasilNatural products comprise valuable sources for new antiparasitic drugs. Here we tested the effects of a novel β-lapachone derivative on Trypanosoma cruzi parasite survival and proliferation and used microscopy and cytometry techniques to approach the mechanism(s) underlying parasite death. The selectivity index determination indicate that the compound trypanocidal activity was over ten-fold more cytotoxic to epimastigotes than to macrophages or splenocytes. Scanning electron microscopy analysis revealed that the R72 β-lapachone derivative affected the T. cruzi morphology and surface topography. General plasma membrane waving and blebbing particularly on the cytostome region were observed in the R72-treated parasites. Transmission electron microscopy observations confirmed the surface damage at the cytostome opening vicinity. We also observed ultrastructural evidence of the autophagic mechanism termed macroautophagy. Some of the autophagosomes involved large portions of the parasite cytoplasm and their fusion/confluence may lead to necrotic parasite death. The remarkably enhanced frequency of autophagy triggering was confirmed by quantitating monodansylcadaverine labeling. Some cells displayed evidence of chromatin pycnosis and nuclear fragmentation were detected. This latter phenomenon was also indicated by DAPI staining of R72-treated cells. The apoptotis induction was suggested to take place in circa one-third of the parasites assessed by annexin V labeling measured by flow cytometry. TUNEL staining corroborated the apoptosis induction. Propidium iodide labeling indicate that at least 10% of the R72-treated parasites suffered necrosis within 24 h. The present data indicate that the β-lapachone derivative R72 selectively triggers T. cruzi cell death, involving both apoptosis and autophagy-induced necrosis

Translational Research on Chagas Disease: Focusing on Drug Combination and Repositioning

Chagas disease, caused by the protozoan Trypanosoma cruzi, is a major neglected disease endemic to Latin America, associated to significant morbimortality comprising a remarkable socioeconomic problem mainly for low-income tropical populations. The present chapter focuses translational research on Chagas disease, approaching drug combinations and repositioning, particularly exploiting the parasite oxidative stress by prospecting prooxidant compounds combined with antagonists of antioxidant systems, for developing low-cost and safe therapies for this infection. The pertinent literature on protozoal parasitic diseases is reviewed as well as on repurposing disulfiram aiming the combination with the Chagas disease drug of choice benznidazole. Both disulfiram and its first derivative sodium diethyldithiocarbamate (DETC) are able not only to inhibit p-glycoprotein, possibly reverting resistance phenotypes, but also to reduce toxicity of numerous other drugs, heavy metals, etc. Therefore, this innovation, presently in clinical research, may furnish a novel therapeutic for T. cruzi infections overcoming the adverse effects and refractory cases that impair the effectiveness of Chagas disease treatment

A divulgação científica para prevenção de doenças endêmicas

Submitted by Martha Martínez Silveira ([email protected]) on 2015-03-31T16:41:50Z No. of bitstreams: 1 Artigo Marcos Vannier final 2 (1) (2).pdf: 4840804 bytes, checksum: a4d5cb5bb1f45f8803f5931b9f79052d (MD5)Approved for entry into archive by Martha Martínez Silveira ([email protected]) on 2015-03-31T17:05:42Z (GMT) No. of bitstreams: 1 Artigo Marcos Vannier final 2 (1) (2).pdf: 4840804 bytes, checksum: a4d5cb5bb1f45f8803f5931b9f79052d (MD5)Made available in DSpace on 2015-03-31T17:05:42Z (GMT). No. of bitstreams: 1 Artigo Marcos Vannier final 2 (1) (2).pdf: 4840804 bytes, checksum: a4d5cb5bb1f45f8803f5931b9f79052d (MD5) Previous issue date: 2010Fundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, Brasil / Conselho Nacional de Desenvolvimento Científico e Tecnológico. Instituto Nacional para Pesquisa Translacional em Saúde e Ambiente na Região Amazônica. BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, Brasil / Conselho Nacional de Desenvolvimento Científico e Tecnológico. Instituto Nacional para Pesquisa Translacional em Saúde e Ambiente na Região Amazônica. BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, Brasil / Conselho Nacional de Desenvolvimento Científico e Tecnológico. Instituto Nacional para Pesquisa Translacional em Saúde e Ambiente na Região Amazônica. BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisa Gonçalo Moniz. Laboratório de Biomorfologia Parasitária. Salvador, BA, Brasil / Conselho Nacional de Desenvolvimento Científico e Tecnológico. Instituto Nacional para Pesquisa Translacional em Saúde e Ambiente na Região Amazônica. BrasilO projeto “ciência na estrada: educação e cidadania” www.bahia.fiocruz.br/ciencianaestrada) é um programa itinerante de educação científica que difunde informações sobre saúde e prevenção de doenças, bem como sobre temas científicos gerais. As atividades do projeto são principalmente dirigidas à populações de baixa renda, onde as doenças infecciosas e parasitárias tendem a ser muito mais comuns, devido às condições sanitárias e de habitação inadequadas. A maioria das atividades vem sendo realizada na Bahia, mas, recentemente, também estamos participando de eventos e estudos na Região Amazônica através do INCT–INPeTAm, CNPq/MCT. Nossa equipe conta com um laboratório itinerante construído dentro de um ônibus equipado com microscópios, câmeras, computadores etc. A intervenção inclui palestras, minicursos e debates sobre doenças parasitárias e sexualmente transmissíveis, entre outras infecções e hábitos de higiene. São empregados cartazes, cartilhas, jogos eletrônicos educativos, vídeos, modelos em resina de parasitos, micróbios, células e incrustações exibindo vetores de doenças parasitárias. Performances teatrais e atividades lúdicas são freqüentemente usadas para esclarecer o público sobre saúde e ciência. Eventualmente exames parasitológicos de fezes, aferição de pressão arterial e testes de grupos sanguíneos são realizados não apenas como serviços para a população, mas também para melhor entender a saúde da comunidade, permitindo o planejamento de uma abordagem mais efetiva de nossas ações. As piores condições de saúde pública foram observadas na periferia e subúrbios das grandes cidades, que a falta de conhecimento científico e saúde foi encontrado principalmente nas áreas rurais. Os alunos abordados em comunidades revisitados apresentaram compreensão de saúde consideravelmente promovida e os pais e professores relataram melhores hábitos de higiene. Estas observações reforçam a idéia de que iniciativas de promoção da saúde e de educação científica itinerantes podem melhorar a saúde pública, apoiando a inclusão social em regiões pobresThe “Science on the Road: education and citizenship” (‘Ciência na Estrada: educação e cidadania’, www.bahia.fiocruz.br/ciencianaestrada) project is an itinerant science education program bringing information on health and disease prevention as well as on general scientific topics. The project activities are mainly directed to low-income populations where parasitic and infectious diseases tend to be much more prevalent, due to inadequate sanitary and housing conditions. Most of the activities were held in Bahia state, but recently we are also taking part in events and studies in the Amazon region via the National Institute for Translational Research on Health and Environment in the Amazon Region, INCT-INPeTAm, CNPq/MCT. Our team counts on an itinerant laboratory built within a bus equipped with microscopes, cameras, computers etc. The intervention includes lectures, short courses and debates on parasitic and sexually-transmitted diseases, among other infections and hygiene habits. We employ posters, booklets, educative electronic games, videos, resin-made models of parasites, microbes and cells and incrustations displaying parasitic disease vectors. Theatrical performances and ludic activities are often used to enlighten the public about health and science. Eventually parasitological stool examinations, blood pressure measurement and blood group tests are performed not only as services for the population, but also to better understand the community health, enabling the planning of a more effective approach for our actions. The worst public health conditions were observed in the suburban periphery of the larger cities, whereas lack of scientific and health knowledge was mainly found in the rural areas. The students approached in communities revisited presented considerably enhanced health understanding and parents/teachers reported better hygienic habits. These observations reinforce the idea that health promotion and science education itinerant initiatives may improve public health, supporting social inclusion in poor region