Browsing by Author "Castro, Renata Alves de Oliveira e"

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    Association of liposome-encapsulated trivalent antimonial with ascorbic acid: an effective and safe strategy in the treatment of experimental visceral. leishmaniasis.
    (2014) Castro, Renata Alves de Oliveira e; Barcellos, Neila Marcia Silva; Licio, Carolina Souza Andrade; Souza, Janine Braga de; Testasicca, Miriam Conceição de Souza; Ferreira, Flávia Monteiro; Batista, Maurício Azevedo; Lemos, Denise da Silveira; Moura, Sandra Aparecida Lima de; Frezard, Frederic Jean Georges; Rezende, Simone Aparecida
    Visceral leishmaniasis (VL) is a chronic debilitating disease endemic in tropical and subtropical areas, caused by protozoan parasites of the genus Leishmania. Annually, it is estimated the occurrence of 0.2 to 0.4 million new cases of the disease worldwide. Considering the lack of an effective vaccine the afflicted population must rely on both, an accurate diagnosis and successful treatment to combat the disease. Here we propose to evaluate the efficacy of trivalent antimonial encapsulated in conventional liposomes, in association with ascorbic acid, by monitoring its toxicity and efficacy in BALB/c mice infected with Leishmania infantum. Methodology/Principal Findings:: Infected mice were subjected to single-dose treatments consisting in the administration of either free or liposome-encapsulated trivalent antimony (SbIII), in association or not with ascorbic acid. Parasite burden was assessed in the liver, spleen and bone marrow using the serial limiting dilution technique. After treatment, tissue alterations were examined by histopathology of liver, heart and kidney and confirmed by serum levels of classic biomarkers. The phenotypic profile of splenocytes was also investigated by flow cytometry. Treatment with liposome-encapsulated SbIII significantly reduced the parasite burden in the liver, spleen and bone marrow. Co-administration of ascorbic acid, with either free SbIII or its liposomal form, did not interfere with its leishmanicidal activity and promoted reduced toxicity particularly to the kidney and liver tissues. Conclusions/Significance:: Among the evaluated posological regimens treatment of L. infantum-infected mice with liposomal SbIII, in association with ascorbic acid, represented the best alternative as judged by its high leishmanicidal activity and absence of detectable toxic effects. Of particular importance, reduction of parasite burden in the bone marrow attested to the ability of SbIII-carrying liposomes to efficiently reach this body compartment.
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    Association of water extract of green propolis and liposomal meglumine antimoniate in the treatment of experimental visceral leishmaniasis.
    (2014) Ferreira, Flávia Monteiro; Castro, Renata Alves de Oliveira e; Batista, Maurício Azevedo; Rossi, Fernanda Mendes de Oliveira; Lemos, Denise da Silveira; Frezard, Frederic Jean Georges; Moura, Sandra Aparecida Lima de; Rezende, Simone Aparecida
    This work investigated the use of water extract of green propolis (WEP) and its association with free or liposomal meglumine antimoniate (MA) for the treatment of murine visceral leishmaniasis. Mice infected with Leishmania infantum were treated with oral doses of WEP associated or not with a single dose of liposomal MA by intraperitoneal route. Parasite burden was assessed in the liver and spleen by limiting dilution assay, and alterations in the spleen cellular phenotype were evaluated by flow cytometry. Tissue damage was assessed by determination of biochemical markers of the liver, heart, and kidney function and histopathological analysis of the liver and spleen. Our data showed that treatmentwith WEP was able to reduce parasite load in the liver but not in the spleen. On the other hand, liposomal MA reduced parasite load in both organs. Unexpectedly, there was no synergism with the combination of WEP and liposomal MA in reducing the parasite load. The histopathological analysis showed that administration of WEP, liposomal MA, or their association was able to protect the liver and spleen fromlesions caused by infection. No alteration in the profile of spleen cells by flow cytometry or in the liver, heart, and kidney functions by biochemical markers due to any of the treatments was observed. These results demonstrate that althoughWEP was able to significantly reduce the liver parasite load, its association with liposomalMA did not lead to significant improvement in reducing parasite load. On the other hand, treatment with WEP and/or liposomal MA protected the liver and spleen from lesions caused by the infection.
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    Avaliação da atividade leishmanicida do antimônio trivalente livre ou em formulação lipossomal convencional, associado ou não ao ácido ascórbico, em camundongos BALB/c infectados com Leishmania infantum.
    (2013) Castro, Renata Alves de Oliveira e; Rezende, Simone Aparecida
    O presente estudo avaliou a utilização de lipossomas convencionais como veículos vetores do antimônio trivalente, na forma de tártaro emético, bem como sua associação ao ácido ascórbico, para o tratamento da leishmaniose visceral no modelo murino. Lipossomas constituídos por distearoilfosfatidilcolina/colesterol (5:4) foram obtidos pela metodologia de congelamento/descongelamento. A caracterização da formulação mostrou tamanho aproximado de 222,5 nm, índice de polidispersão de 0,214, eficiência de encapsulação de 15%, concentração final de 4 mg SbIII/mL e cinética de liberação bifásica avaliada in vitro. Lipossomas vazios, igualmente obtidos e hidratados com tampão fosfato serviram como controle. Camundongos BALB/c com idade entre 6 e 8 semanas foram inoculados com 1 x 107 promastigotas de Leishmania (Leishmania) infantum (cepa C43) por via endovenosa. Após seis semanas de infecção, os animais foram divididos em sete grupos (n=8) e tratados por via intraperitoneal, em dose única com: (1) tampão fosfato, (2) antimônio trivalente (SbIII) - 9 mgSb/Kg, (3) lipossomas vazios, (4) lipossomas de SbIII (9 mgSb/Kg), (5) ácido ascórbico (AA) - 300 mg/kg; (6) associação do AA (300 mg/kg) ao SbIII (9 mgSb/kg) e (7) associação de AA (300 mg/kg) aos lipossomas de SbIII (9 mgSb/kg). Dez dias após o tratamento, os animais foram eutanasiados e avaliou-se: a carga parasitária no fígado, baço e medula óssea pelo método de diluição limitante; o padrão de células do baço por citometria de fluxo; a função renal, hepática e cardíaca por análises bioquímicas e o padrão histopatológico do fígado, rins e coração. Observou-se redução significativa na carga parasitária após tratamento com antimônio trivalente lipossomal no fígado, baço e medula óssea de 47%, 33% e 47%, respectivamente, indicando a capacidade do sistema de vetorização de direcionar o medicamento para esses compartimentos. A administração concomitante do AA e SbIII livre ou em formulação lipossomal não interferiu na atividade leishmanicida do SbIII. Não foi observada diminuição na carga parasitária após tratamento com antimônio trivalente livre em nenhum dos órgãos avaliados. Os resultados mostraram nenhuma alteração no padrão fenotípico de células do baço por citometria de fluxo ou nas funções hepática, cardíaca e renal por análises bioquímicas. As análises histopatológicas mostraram que a coadministração dos lipossomas de SbIII e AA foi capaz de preservar os tecidos hepático e renal quando comparados os diferentes grupos experimentais. Os resultados desse trabalho permitiram concluir que a referida preparação lipossomal representa uma alternativa terapêutica capaz de reduzir a carga parasitária nos diferentes órgãos alvo, com potencial para a eliminação do parasito na medula óssea. A coadministração do AA aos lipossomas de SbIII acarretou redução na toxicidade do SbIII. Em conjunto, nossos dados apontam os benefícios do encapsulamento do SbIII em lipossomas unilamelares demonstrados pela redução das alterações histopatológicas para fígado e rins, particularmente em combinação com AA. Acreditamos que nosso trabalho será útil para a proposição de novos regimes terapêuticos para o tratamento da leishmaniose visceral, garantindo a adesão do paciente à terapia devido à redução dos efeitos colaterais.
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    Multicomponent LBSap vaccine displays immunological and parasitological profiles similar to those of Leish-Tec® and Leishmune® vaccines against visceral leishmaniasis.
    (2016) Mendonça, Ludmila Zanandreis de; Resende, Lucilene Aparecida; Lanna, Mariana Ferreira; Soares, Rodrigo Dian de Oliveira Aguiar; Roatt, Bruno Mendes; Castro, Renata Alves de Oliveira e; Batista, Maurício Azevedo; Lemos, Denise da Silveira; Estanislau, Juliana de Assis Silva Gomes; Fujiwara, Ricardo Toshio; Rezende, Simone Aparecida; Martins Filho, Olindo Assis; Oliveira, Rodrigo Corrêa de; Dutra, Walderez Ornelas; Reis, Alexandre Barbosa; Giunchetti, Rodolfo Cordeiro
    Background: In past years, many researchers have sought canine visceral leishmaniasis (CVL) prevention through the characterization of Leishmania antigens as vaccine candidates. Despite these efforts, there is still no efficient vaccine for CVL control. Methods: In the present study, we performed a pre-clinical vaccine trial using BALB/c mice to compare the effects of the multicomponent LBSap vaccine with those of Leish-Tec® and Leishmune®. Blood was collected to determine the frequency of peripheral blood cells and to evaluate hematologic and immunophenotypic parameters. Liver and spleen samples were collected for parasitological quantification, and spleen samples were used to access the cytokine profile. Results: When measuring total IgG and IgG1 anti-Leishmania levels after the third vaccination and L. infantum challenge, it was evident that all vaccines were able to induce humoral immune response. Regarding the innate immune response, increased levels of NK CD3-CD49+ cells were the hallmark of all vaccinated groups, whereas only the Leish-Tec® group displayed a high frequency of CD14+ monocytes after L. infantum challenge. Moreover, CD3+CD4+ T cells were the main circulating lymphocytes induced after L. infantum challenge with all evaluated vaccines. Importantly, after L. infantum challenge, splenocytes from the Leishmune® vaccine produced high levels of IL-2, whereas a prominent type 1 immune response was the hallmark of the LBSap vaccine, which presented high levels of IL-2, IL-6, TNF-α, and IFN-γ. The efficacy analysis using real-time polymerase chain reaction demonstrated a reduction in the parasitism in the spleen (Leishmune®: 64 %; LBSap: 42 %; and Leish-Tec®: 36 %) and liver (Leishmune®: 71 %; LBSap: 62 %; and Leish-Tec®: 48 %). Conclusions: The dataset led to the conclusion that the LBSap vaccination was able to induce immune and efficacy profiles comparable with those of commercial vaccines, thus demonstrating its potential as a promising vaccine candidate for visceral leishmaniasis control.
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    População leucocitária e expressão de CD39 e CD73 durante o curso da infecção por Leishmania amazonensis.
    (2019) Castro, Renata Alves de Oliveira e; Afonso, Luís Carlos Crocco; Afonso, Luís Carlos Crocco; Roatt, Bruno Mendes; Carneiro, Cláudia Martins; Gomes, Daniel Cláudio de Oliveira; Gonçalves, Ricardo
    O ATP extracelular induz uma resposta inflamatória regulada por sua hidrólise à adenosina pela ação sequencial de CD39 e CD73. A adenosina, por outro lado, induz uma resposta anti- inflamatória. O objetivo deste estudo foi avaliar a cinética de migração celular, a expressão de CD39 e CD73 e a produção de citocinas em linfonodos que drenam uma infecção na orelha por L. amazonensis (103 metacíclicas), no modelo murino. A análise de citocinas (IFN- e IL-10) produzidas por cultura de células de linfonodo drenante nos tempos analisados demonstra um balanço, pró e anti-inflamatório, tanto nos tempos iniciais (baixas em 3 e 1 semana) quanto nos tempos tardios (alta em 7 e 10 semanas). Fotomicrografias das lesões de orelha evidenciam um atraso na formação do processo inflamatório e, a partir de 7 semanas, presença de infiltrado inflamatório misto. A análise por citometria de fluxo mostra aumento da população CD45+ e ectonucleotidases na orelha e linfonodo drenante em 7 e 10 semanas de infecção. Em 3 dias ocorre aumento da população CD45+ e expressão de CD39+ /CD73+ na orelha, independente do grupo analisado, provavelmente devido ao inóculo. No linfonodo, as APCs têm um aumento em 7 e 10 semanas e CD39 e CD73 estão em alta expressão. Na orelha, a população de macrófagos aumenta em 10 semanas de infecção com alta expressão de CD39 ou CD73. Os monócitos inflamatórios aumentam na orelha e linfonodo em 10 semanas com alta de ectonucleotidases. Os neutrófilos aumentam em 7 e 10 semanas no linfonodo e orelha, respectivamente e, têm aumento da expressão das enzimas. Os linfócitos TCD4+ aumentam no linfonodo em 7 semanas e regridem em 10 semanas, enquanto na orelha estão presentes apenas em 10 semanas com aumento da expressão de CD39. No linfonodo a população Treg, tem aumento em 7 e 10 semanas. Tanto na orelha quanto no linfonodo a população CD8+ /CD39+ está aumentada em 10 semanas, em um padrão de exaustão. As células NK estão aumentadas em 7 e 10 semanas no linfonodo e orelha com aumento de ectonucleotidases. Nossos resultados nos permitem concluir que existe correlação entre o aumento da população celular no infiltrado inflamatório da lesão e a expressão de ectonucleotidases durante o curso da infecção por L. amazonensis. Este padrão de enzimas exerce uma regulação importante que suplanta a ação das citocinas. As alterações celulares em linfócitos parecem apontar para uma similaridade entre o local de infecção por este parasito e o ambiente tumoral causada pela modulação do sistema imune por ectonucleotidases.
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    The schistosomiasis spleenOME : unveiling the proteomic landscape of splenomegaly using label-free mass spectrometry.
    (2019) Cosenza Contreras, Miguel de Jesus; Castro, Renata Alves de Oliveira e; Mattei, Bruno; Campos, Jonatan Marques; Silva, Gustavo Gonçalves; Paiva, Nívia Carolina Nogueira de; Soares, Rodrigo Dian de Oliveira Aguiar; Carneiro, Cláudia Martins; Afonso, Luís Carlos Crocco; Borges, William de Castro
    Schistosomiasis is a neglected parasitic disease that affects millions of people worldwide and is caused by helminth parasites from the genus Schistosoma. When caused by S. mansoni, it is associated with the development of a hepatosplenic disease caused by an intense immune response to the important antigenic contribution of adult worms and to the presence of eggs trapped in liver tissue. Although the importance of the spleen for the establishment of immune pathology is widely accepted, it has received little attention in terms of the molecular mechanisms operating in response to the infection. Here, we interrogated the spleen proteome using a label-free shotgun approach for the potential discovery of molecular mechanisms associated to the peak of the acute phase of inflammation and the development of splenomegaly in the murine model. Over fifteen hundred proteins were identified in both infected and control individuals and 325 of those proteins were differentially expressed. Two hundred and forty-two proteins were found upregulated in infected individuals while 83 were downregulated. Functional enrichment analyses for differentially expressed proteins showed that most of them were categorized within pathways of innate and adaptive immunity, DNA replication, vesicle transport and catabolic metabolism. There was an important contribution of granulocyte proteins and antigen processing and presentation pathways were augmented, with the increased expression of MHC class II molecules but the negative regulation of cysteine and serine proteases. Several proteins related to RNA processing were upregulated, including splicing factors. We also found indications of metabolic reprogramming in spleen cells with downregulation of proteins related to mitochondrial metabolism. Ex-vivo imunophenotyping of spleen cells allowed us to attribute the higher abundance of MHC II detected by mass spectrometry to increased number of macrophages (F4/80+/MHC II+ cells) in the infected condition. We believe these findings add novel insights for the understanding of the immune mechanisms associated with the establishment of schistosomiasis and the processes of immune modulation implied in the host-parasite interactions.
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    Understanding global changes of the liver proteome during murine schistosomiasis using a label-free shotgun approach.
    (2016) Campos, Jonatan Marques; Neves, Leandro Xavier; Paiva, Nívia Carolina Nogueira de; Castro, Renata Alves de Oliveira e; Casé, Ana Helena; Carneiro, Cláudia Martins; Andrade, Milton Hércules Guerra de; Borges, William de Castro
    Schistosomiasis is an endemic disease affecting over 207million people worldwide caused by helminth parasites of the genus Schistosoma. In Brazil the disease is responsible for the loss of up to 800 lives annually, resulting from the desabilitating effects of this chronic condition. In this study, we infected Balb/c mice with Schistosoma mansoni and analysed global changes in the proteomic profile of soluble liver proteins. Our shotgun analyses revealed predominance of up-regulation of proteins at 5weeks of infection, coincidingwith the onset of egg laying, and a remarkable down-regulation of liver constituents at 7 weeks, when severe tissue damage is installed. Representatives of glycolytic enzymes and stress response (in particular at the endoplasmic reticulum)were among the most differentially expressed molecules found in the infected liver. Collectively, our data contribute over 70 molecules not previously reported to be found at altered levels in murine schistosomiasis to further exploration of their potential as biomarkers of the disease.Moreover, understanding their intricate interaction using bioinformatics approach can potentially bring clarity to unknownmechanisms linked to the establishment of this condition in the vertebrate host. Significance: To our knowledge, this study refers to the first shotgun proteomic analysis to provide an inventory of the global changes in the liver soluble proteome caused by Schistosomamansoni in the Balb/cmodel. It also innovates by yielding data on quantification of the identified molecules as a manner to clarify and give insights into the underlying mechanisms for establishment of Schistosomiasis, a neglected tropical disease with historical prevalence in Brazil.