Unlocking the in vitro anti-Trypanosoma cruzi activity of halophyte plants from the southern Portugal

Objective: To evaluate the in vitro anti-Trypanosoma cruzi (T. cruzi) activity of organic extracts prepared from halophyte species collected in the southern coast of Portugal (Algarve), and chemically characterize the most active samples.Methods: Acetone, dichloromethane and methanol extracts were prepared from 31 halophyte species and tested in vitro against trypomastigotes and intracellular amastigotes of the Tulahuen strain of T. cruzi. The most active extract was fractionated by preparative HPLC-DAD, affording 11 fractions. The most selective fraction was fully characterized by H-1 NMR.Results: From 94 samples tested, one was active, namely the root dichloromethane extract of Juncus acutus (IC50 < 20 mu g/mL). This extract was fractionated by HPLC, affording 11 fractions, one of them containing only a pure compound (juncunol), and tested for anti-parasitic activity. Fraction 8 (IC50 = 4.1 mu g/mL) was the most active, and was further characterized by H-1 NMR. The major compounds were phenanthrenes, 9,10-dihydrophenanthrenes and benzocoumarins.Conclusion: Our results suggest that the compounds identified in fraction 8 are likely responsible for the observed anti parasitic activity. Further research is in progress aiming to isolate and identify the specific active molecules. To the best of our knowledge, this is the first report on the in vitro anti T. cruzi activity of halophyte species.PROEP/CNPq/FIOCRUZ 401988/2012-0; FCT/CAPES 2358, 2014/201

Experimental and Clinical Treatment of Chagas Disease : A Review

Altres ajuts: This study was supported by the European Comission under the Health Innovation Work Program of the 7th Framework Program and by CAPES/Brasil, Programa Ciencia Sem Fronteiras and Professor ˆ Visitante Nacional Senior. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have no conflict of interests.Chagas disease (CD) is caused by the protozoan parasite Trypanosoma cruzi that infects a broad range of triatomines and mammalian species, including man. It afflicts 8 million people in Latin America, and its incidence is increasing in nonendemic countries owing to rising international immigration and nonvectorial transmission routes such as blood donation. Since the 1960s, the only drugs available for the clinical treatment of this infection have been benznidazole (BZ) and nifurtimox (NFX). Treatment with these trypanocidal drugs is recommended in both the acute and chronic phases of CD. These drugs have low cure rates mainly during the chronic phase, in addition both drugs present side effects that may result in the interruption of the treatment. Thus, more efficient and better-tolerated new drugs or pharmaceutical formulations containing BZ or NFX are urgently needed. Here, we review the drugs currently used for CD chemotherapy, ongoing clinical assays, and most-promising new experimental drugs. In addition, the mechanism of action of the commercially available drugs, NFX and BZ, the biodistribution of the latter, and the potential for novel formulations of BZ based on nanotechnology are discussed. Taken together, the literature emphasizes the urgent need for new therapies for acute and chronic CD

Vaccination Using Recombinants Influenza and Adenoviruses Encoding Amastigote Surface Protein-2 Are Highly Effective on Protection against Trypanosoma cruzi Infection

In the present study we evaluated the protection raised by immunization with recombinant influenza viruses carrying sequences coding for polypeptides corresponding to medial and carboxi-terminal moieties of Trypanosoma cruzis amastigote surface protein 2 (ASP2). Those viruses were used in sequential immunization with recombinant adenovirus (heterologous prime-boost immunization protocol) encoding the complete sequence of ASP2 (Ad-ASP2) in two mouse strains (C57BL/6 and C3H/He). the CD8 effector response elicited by this protocol was comparable to that observed in mice immunized twice with Ad-ASP2 and more robust than that observed in mice that were immunized once with Ad-ASP2. Whereas a single immunization with Ad-ASP2 sufficed to completely protect C57BL/6 mice, a higher survival rate was observed in C3H/He mice that were primed with recombinant influenza virus and boosted with Ad-ASP2 after being challenged with T. cruzi. Analyzing the phenotype of CD8+ T cells obtained from spleen of vaccinated C3H/He mice we observed that heterologous prime-boost immunization protocol elicited more CD8+ T cells specific for the immunodominant epitope as well as a higher number of CD8+ T cells producing TNF-alpha and IFN-gamma and a higher mobilization of surface marker CD107a. Taken together, our results suggest that immunodominant subpopulations of CD8+ T elicited after immunization could be directly related to degree of protection achieved by different immunization protocols using different viral vectors. Overall, these results demonstrated the usefulness of recombinant influenza viruses in immunization protocols against Chagas Disease.FIOCRUZ/PDTIS-VacinasConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG)Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Bioquim & Imunol, Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Microbiol, Belo Horizonte, MG, BrazilUniv Fed Minas Gerais, Inst Ciencias Biol, Dept Morfol, Belo Horizonte, MG, BrazilFiocruz MS, Ctr Pesquisas Rene Rachou, Belo Horizonte, MG, BrazilUniversidade Federal de São Paulo, Escola Paulista Med, Ctr Terapia Celular & Mol CTCMol, São Paulo, BrazilUniv Massachusetts, Sch Med, Dept Med, Div Infect Dis & Immunol, Worcester, MA USAUniversidade Federal de São Paulo, Escola Paulista Med, Ctr Terapia Celular & Mol CTCMol, São Paulo, BrazilCNPq: 015/2008CNPq: 064/2008Web of Scienc

Utilization of biodegradable PLGA microspheres as a delivery system for synthetic vaccine SBm7462 on control of the Boophilus microplus (Canestrini, 1887): experimental model in mice

Foi avaliada a resposta imunológica do peptídeo sintético SBm7462 emulsificado com o adjuvante saponina ou encapsulado em microesferas biodegradáveis PLGA; bem como, a do peptídeo sintético SPf66 encapsulado no referido sistema de liberação. O estudo foi realizado com camundongos Balb/c, fêmeas, utilizando-se uma dose de 100 mg de peptídeo por animal. Os camundongos foram separados em seis grupos de vinte: grupo I: animais em que foram inoculados 75mg de saponina; grupo II: inoculados com 100 mL de água milli Q; grupo III: imunizados com o peptídeo SBm7462 emulsificado com o adjuvante saponina (75mg de saponina para 100mg de peptídeo); grupo IV: inoculados com as microesferas vazias; grupo V: imunizados com o peptídeo SBm7462 encapsulado nas microesferas PLGA; grupo VI: imunizados com o peptídeo sintético SPf66 encapsulado nas microesferas PLGA. As três inoculações foram efetuadas no dia zero e depois a cada três semanas. Os camundongos foram sangrados antes da primeira imunização e a intervalos periódicos (a cada sete dias) até 21ª semana, sendo o soro utilizado para a realização de ELISA indireto para detecção de IgGs anti-SBm7462, como também para a realização de testes de função hepática. O peptídeo sintético SBm7462 mostrou uma melhor resposta humoral quando emulsificado com o adjuvante saponina. Já o SPf66 mostrou uma resposta similar à encontrada por outros autores quando encapsulado em microesferas PLGA e utilizado em camundongos. Os testes de função hepática foram realizados em equipamento multiparamétrico de bioquímica Alisé e, não se observou evidências de efeitos hepatotóxicos quando foram avaliados parâmetros como proteínas totais, albumina, AST e ALT. Foram também coletados baços de camundongos para verificação das alterações histológicas pós-imunização, para cada tratamento, no dia zero, três, seis e nove dias após a segunda e dois, quatro e seis dias após a terceira inoculação. Os resultados obtidos revelam que a saponina potencializa uma melhor resposta imune do peptídeo SBm7462, tendo sido também esta resposta mais precoce e que, as microesferas PLGA mostram-se viáveis a serem utilizadas como sistema de liberação para este peptídeo, necessitando-se, porém, de estudos adicionais para promoção de uma melhor eficácia de encapsulação.Was evaluated the immunological response of synthetic peptide SBm7462 emulsified with the adjuvant saponin or encapsulated in biodegradable PLGA microspheres; as well as, the response of synthetic peptide SPf66 encapsulated on cited delivery system. Mice Balb/c, female, were utilized on study, with a dose of 100mg of peptide for each animal. The mice were separated in six groups of twenty: group I: animals inoculated with 75mg of saponin; group II: inoculated with 100mL of water milliQ; group III: immunized with the peptide SBm7462 emulsified on saponin, 75mg of saponin for 100mg of peptide; group IV: inoculated with empty microspheres; group V: immunized with the peptide SBm7462 enclausured in PLGA microspheres; group VI: immunized with the synthetic peptide SPf66 enclausured in PLGA microspheres. The three inoculations was executed on day zero and latter on third and sixth weeks after the first inoculation. The mice were bled prior of first immunisation and at periodic intervals (of seven days) until week 21. The serum was assayed by indirect ELISA for detection of specific IgGs anti-SBm7462, and for realization of tests of hepatic function. The synthetic peptide SBm7462 showed a better immune response emulsified with saponin adjuvant. The peptide SPf66 showed a similar response when compared with the obtained for others authors when encapsulated in PLGA microspheres and utilized in mice. The tests of hepatic function were realized in equipament multiparametric of bioquimic Alisé, and no evidence of hepatotoxic effects was viewed, when was evaluated the parameters: total proteins, albumin, AST and ALT. In order to verification of histologic alterations post-immunization, were colleted spleen of mice, for each treatment, on day zero, three, six and nine days post the second inoculation and two, four and six days post the third inoculation. The results obtained showed the saponin potentiate a better immune response of peptide SBm7462, and this response was more precoce than the obtained with the PLGA microspheres. This delivery system show itself as a good approach for utilization with the synthetic peptide SBm7462, nevertheless more studies are necessary for promotion of a better efficacy of encapsulation.Fundação Oswaldo Cru

Altered cardiomyocyte function and trypanosoma cruzi persistence in chagas disease

Chagas disease, caused by the triatominae Trypanosoma cruzi, is one of the leading causes of heart malfunctioning in Latin America. The cardiac phenotype is observed in 20-30% of infected people 10-40 years after their primary infection. The cardiac complications during Chagas disease range from cardiac arrhythmias to heart failure, with important involvement of the right ventricle. Interestingly, no studies have evaluated the electrical properties of right ventricle myocytes during Chagas disease and correlated them to parasite persistence. Taking advantage of a murine model of Chagas disease, we studied the histological and electrical properties of right ventricle in acute (30 days postinfection [dpi]) and chronic phases (90 dpi) of infected mice with the Colombian strain of T. cruzi and their correlation to parasite persistence. We observed an increase in collagen deposition and inflammatory infiltrate at both 30 and 90 dpi. Furthermore, using reverse transcriptase polymerase chain reaction, we detected parasites at 90 dpi in right and left ventricles. In addition, we observed action potential prolongation and reduced transient outward K+ current and L-type Ca2+ current at 30 and 90 dpi. Taking together, our results demonstrate that T. cruzi infection leads to important modifications in electrical properties associated with inflammatory infiltrate and parasite persistence in mice right ventricle, suggesting a causal role between inflammation, parasite persistence, and altered cardiomyocyte function in Chagas disease. Thus, arrhythmias observed in Chagas disease may be partially related to altered electrical function in right ventricle.CNPq [404353/2012-6]FAPESP [2014/09861-1]Universidade Federal de Minas Gerais, Inst Ciencias Biol, Dept Bioquim & Imunol, Belo Horizonte, Minas Gerais, BrazilCentro de Pesquisas René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Lab Parasitol Celular & Mol, Belo Horizonte, Minas Gerais, BrazilEscola Paulista de Medicina, Universidade Federal de São Paulo, Departamento de Biofisica, São Paulo, BrazilUniversidade Federal de Minas Gerais, Inst Ciencias Biol, Dept Patol Geral, Belo Horizonte, Minas Gerais, BrazilDepartamento de Biofisica, Escola Paulista de Medicina, Universidade Federal de São Paulo, Rua Botucatu 862, Vila Clementino, São Paulo, São Paulo, Brazil, CEP 04023062CNPq: 404353/2012-6FAPESP: 2014/09861-1Web of Scienc

Experimental and Clinical Treatment of Chagas Disease : A Review

Altres ajuts: This study was supported by the European Comission under the Health Innovation Work Program of the 7th Framework Program and by CAPES/Brasil, Programa Ciencia Sem Fronteiras and Professor ˆ Visitante Nacional Senior. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The authors have no conflict of interests.Chagas disease (CD) is caused by the protozoan parasite Trypanosoma cruzi that infects a broad range of triatomines and mammalian species, including man. It afflicts 8 million people in Latin America, and its incidence is increasing in nonendemic countries owing to rising international immigration and nonvectorial transmission routes such as blood donation. Since the 1960s, the only drugs available for the clinical treatment of this infection have been benznidazole (BZ) and nifurtimox (NFX). Treatment with these trypanocidal drugs is recommended in both the acute and chronic phases of CD. These drugs have low cure rates mainly during the chronic phase, in addition both drugs present side effects that may result in the interruption of the treatment. Thus, more efficient and better-tolerated new drugs or pharmaceutical formulations containing BZ or NFX are urgently needed. Here, we review the drugs currently used for CD chemotherapy, ongoing clinical assays, and most-promising new experimental drugs. In addition, the mechanism of action of the commercially available drugs, NFX and BZ, the biodistribution of the latter, and the potential for novel formulations of BZ based on nanotechnology are discussed. Taken together, the literature emphasizes the urgent need for new therapies for acute and chronic CD

Evaluation of the bactericidal and trypanocidal activities of triterpenes isolated from the leaves, stems, and flowers of Lychnophora pinaster

Submitted by Nuzia Santos ([email protected]) on 2014-07-23T12:47:48Z No. of bitstreams: 1 Evaluation of the bactericidal and trypanocidal activities of triterpenes isolated from the leaves.pdf: 1241066 bytes, checksum: aed870035171b21bf40d1e1d14ad9ed1 (MD5)Made available in DSpace on 2014-07-23T12:47:49Z (GMT). No. of bitstreams: 1 Evaluation of the bactericidal and trypanocidal activities of triterpenes isolated from the leaves.pdf: 1241066 bytes, checksum: aed870035171b21bf40d1e1d14ad9ed1 (MD5) Previous issue date: 2011Universidade Federal de Minas Gerais. Instituto de Ciências Exatas. Departamento de Química. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Exatas. Departamento de Química. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Exatas. Departamento de Química. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Exatas. Departamento de Química. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Parasitologia Celular e Molecular. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Parasitologia Celular e Molecular. Belo Horizonte, MG, BrasilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Laboratório de Parasitologia Celular e Molecular. Belo Horizonte, MG, BrasilUniversidade Federal de Minas Gerais. Instituto de Ciências Exatas. Departamento de Química. Belo Horizonte, MG, BrasilThe phytochemical investigation on the aereal parts of Lychnophora pinaster Mart., Asteraceae, was carried to isolation of triterpenes. 3-O-Acetyl-lupeol (1), 3-O-acetyl-pseudotaraxasterol (2), and 3-O-acetyl-α-amyrin (3) were isolated from hexanic extract and 4,4-dimethyl-cholesta-22,24-dien-5-ol (4), α-amyrin (5), and lupeol (6) were isolated from hexanic/dichlorometanic extract of the leaves. Compounds Δ7-bauerenyl acetate (7), friedelin (8), stigmasterol (9), and sitosterol (10) were isolated from the hexanic/dichlorometanic extract of the stems. The steroids 9 and 10 were also isolated from the hexanic/dichlorometanic extract of the flowers. Triterpenes 1, 3, 4, and 7 are described for the first time in the genus Lychnophora. The apolar fractions of the leaf and stem extracts and some isolated triterpenes showed low trypanocidal activity. Moreover, apolar fractions of the leaf and stem extracts and 5 showed antibacterial action against Staphylococcus aureus

Synthesis of Xylitan Derivatives and Preliminary Evaluation of in Vitro Trypanocidal Activity.

Submitted by Nuzia Santos ([email protected]) on 2017-02-14T17:42:02Z No. of bitstreams: 1 ve_Elias_Paula_Synthesis_CPqRR_2016.pdf: 449032 bytes, checksum: 2f8e06eeec6cee1a51be86183a80c8d1 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2017-02-14T17:48:24Z (GMT) No. of bitstreams: 1 ve_Elias_Paula_Synthesis_CPqRR_2016.pdf: 449032 bytes, checksum: 2f8e06eeec6cee1a51be86183a80c8d1 (MD5)Made available in DSpace on 2017-02-14T17:48:24Z (GMT). No. of bitstreams: 1 ve_Elias_Paula_Synthesis_CPqRR_2016.pdf: 449032 bytes, checksum: 2f8e06eeec6cee1a51be86183a80c8d1 (MD5) Previous issue date: 2016Universidade Federal de Ouro Preto. Instituto de Ciências Exatas e Biológicas. Departamento de Quimica. Ouro Preto, MG, BrazilUniversidade Federal de Ouro Preto. Instituto de Ciências Exatas e Biológicas. Departamento de Quimica. Ouro Preto, MG, BrazilUniversidade Federal de Ouro Preto. Instituto de Ciências Exatas e Biológicas. Departamento de Quimica. Ouro Preto, MG, Brazil/Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilUniversidade Federal de Ouro Preto. Núcleo de Pesquisas em Ciências Biológicas. Laboratorio de Imunopatologia. Ouro Preto, MG, BrazilUniversidade Estadual de Campinas. Instituto de Química. Campinas, SP, BrazilUniversidade Federal de Ouro Preto. Instituto de Ciências Exatas e Biológicas. Departamento de Quimica. Ouro Preto, MG, BrazilUniversidade Federal de Ouro Preto. Instituto de Ciências Exatas e Biológicas. Departamento de Quimica. Ouro Preto, MG, BrazilA series of novel xylitan derivatives derived from xylitol were synthesized using operationally simple procedures. A xylitan acetonide was the key intermediate used to prepare benzoate, arylsulfonate esters and 1,2,3-triazole derivatives of xylitan. These compounds were evaluated for their in vitro anti-Trypanosoma cruzi activity against trypomastigote and amastigote forms of the parasite in T. cruzi-infected cell lineages. Benznidazole was used as positive control against T. cruzi and cytotoxicity was determined in mammalian L929 cells. The arylsulfonate xylitan derivative bearing a nitro group displayed the best activity of all the compounds tested, and was slightly more potent than the reference drug benznidazole. The importance of the isopropylidene ketal moiety was established and the greater lipophilicity of these compounds suggests enhancement in cell penetration

Vaccination Using Recombinants Influenza and Adenoviruses Encoding Amastigote Surface Protein-2 Are Highly Effective on Protection against Trypanosoma cruzi Infection

In the present study we evaluated the protection raised by immunization with recombinant influenza viruses carrying sequences coding for polypeptides corresponding to medial and carboxi-terminal moieties of Trypanosoma cruzi ´s amastigote surface protein 2 (ASP2). Those viruses were used in sequential immunization with recombinant adenovirus (heterologous prime-boost immunization protocol) encoding the complete sequence of ASP2 (Ad-ASP2) in two mouse strains (C57BL/6 and C3H/He). The CD8 effector response elicited by this protocol was comparable to that observed in mice immunized twice with Ad-ASP2 and more robust than that observed in mice that were immunized once with Ad-ASP2. Whereas a single immunization with Ad-ASP2 sufficed to completely protect C57BL/6 mice, a higher survival rate was observed in C3H/He mice that were primed with recombinant influenza virus and boosted with Ad-ASP2 after being challenged with T. cruzi. Analyzing the phenotype of CD8+ T cells obtained from spleen of vaccinated C3H/He mice we observed that heterologous prime-boost immunization protocol elicited more CD8+ T cells specific for the immunodominant epitope as well as a higher number of CD8+ T cells producing TNF-α and IFN-γ and a higher mobilization of surface marker CD107a. Taken together, our results suggest that immunodominant subpopulations of CD8+ T elicited after immunization could be directly related to degree of protection achieved by different immunization protocols using different viral vectors. Overall, these results demonstrated the usefulness of recombinant influenza viruses in immunization protocols against Chagas Disease.status: publishe