Browsing by Author "Milagre, Matheus Marques"

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    Activity of the sesquiterpene lactone goyazensolide against Trypanosoma cruzi in vitro and in vivo.
    (2020) Milagre, Matheus Marques; Branquinho, Renata Tupinambá; Gonçalves, Maíra Fonseca; Assis, Gabriela Maíra Pereira de; Oliveira, Maykon Tavares de; Reis, Levi Eduardo Soares; Guimarães, Dênia Antunes Saúde; Lana, Marta de
    Background: The current drugs for Chagas disease treatment present several limitations Methods: The sesquiterpene lactone goyazensolide (GZL) was evaluated regarding to cytotoxicity and trypanocidal activity against amastigotes, selectivity index (SI) in vitro, acute toxicity and anti-Trypanosoma cruzi activity in vivo. Results: The in vitro cytotoxicity in H9c2 cells was observed at doses >250 ng mL−1 of GZL and the SI were of 52.82 and 4.85 (24 h) and of 915.00 and 41.00 (48 h) for GZL and BZ, respectively. Nephrotoxicity and hepatotoxicity were not verified. Treatment with GZL of mice infected with CL strain led to a significant decrease of parasitaemia and total survival at doses of 1 and 3 mg kg−1 day−1 by oral and IV, respectively. This last group cured 12.5% of the animals (negativation of HC, PCR, qPCR and ELISA). Animals infected with Y strain showed significant decrease of parasitaemia and higher negativation in all parasitological tests in comparison to BZ and control groups, but were ELISA reactive, as well as the BZ group, but mice treated with 5.0 mg kg−1 day−1 by oral were negative in parasitological tests and survived. Conclusion: GZL was more active against T. cruzi than benznidazole in vitro and presented important therapeutic activity in vivo in both T. cruzi strains.
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    Avaliação anti-Trypanosoma cruzi in vitro e in vivo de lactona sesquiterpênica isolada de Lychnophora passerina.
    (2018) Milagre, Matheus Marques; Lana, Marta de; Guimarães, Dênia Antunes Saúde; Alves, Tânia Maria Almeida; Vieira Filho, Sidney Augusto; Lana, Marta de
    Atualmente, a única droga disponível para tratar a DCh no Brasil é o benznidazol (BZ), que apresenta várias limitações e efeitos adversos, dessa forma estimulando a busca por novas opções terapêuticas. Assim, este projeto visa o uso em solução da lactona sesquiterpênica goyazensolida (GZL), previamente ativa contra o Trypanosoma cruzi in vitro, com os seguintes objetivos: (1) Determinar o limiar de citotoxicidade in vitro sobre células de mamíferos (H9c2) e avaliar sua atividade tripanocida contra amastigotas, estabelecendo seu índice de seletividade; (2) Avaliar os sinais de toxicidade aguda in vivo e sua atividade frente à infecção experimental de T. cruzi em modelo murino. Para avaliar a citotoxicidade foram realizados os testes MTT e Vermelho Neutro (VN) e, para verificar a atividade da GZL contra o T. cruzi, células H9c2 foram infectadas com um isolado resistente da cepa Y de T. cruzi e tratadas durante 24 e 48h. Na avaliação da toxicidade aguda in vivo, foi determinada a dose máxima tolerada, feito o hemograma e dosagem de parâmetros bioquímicos para avaliação da toxicidade hepática e renal. Para avaliar a atividade terapêutica da GZL, camundongos Swiss infectados com as cepas Y e CL de T. cruzi foram tratados pelas vias oral e intravenosa (IV) por 20 dias consecutivos nas doses de 1, 5 e 25 mg/kg/dia [via oral e IV, cepa Y (isolado resistente ao BZ) e CL (sensível ao BZ)] e 1, 3 e 9 mg/kg/dia IV (cepa CL), paralelamente a grupos controles BZ 100mg/kg/dia e infectado não tratados (INT). A parasitemia dos animais foi avaliada diariamente até consistente negativação. A ação do tratamento foi avaliada ainda por exames parasitológicos (hemocultura e PCR) e sorológico (ELISA). Os resultados obtidos revelaram a citotoxicidade in vitro da GZL em concentrações acima de 250 ng/mL nos tratamentos de 24 e 48h avaliadas pelos testes MTT e VN, sendo o índice de seletividade em 24h de 351 calculado a partir da relação dos parâmetros de MTT e do teste de ação tripanocida da GZL in vitro. Houve discreta nefrotoxicidade revelada pelo aumento de creatinina observado nos animais tratados com GZL 25 mg/kg IV em relação ao grupo CNT. Na avaliação pós-tratamento em animais infectados pela cepa Y, foi observada uma diminuição significativa da parasitemia a partir do 5º dia de tratamento com GZL nas doses de 1,0 mg/kg/dia (IV e oral) e 5,0 mg/kg/dia, via oral e BZ 100 mg/kg/dia, quando comparados ao grupo controle INT. As taxas de sobrevivência dos camundongos tratados com GZL foram de 100% na dose de 5,0 mg/kg/dia oral, seguidos dos tratados com 1,0 mg/kg/dia IV e BZ 100 mg/kg/dia oral, que foram de 87,5%, enquanto o grupo controle INT apresentou 25% de sobrevida. Nenhum dos camundongos foram considerados curados segundo o critério de cura adotado (MS, 2016). Os animais infectados pela cepa CL e tratados com GZL demonstraram no 180º dia pós-tratamento uma diminuição significativa da parasitemia a partir do primeiro dia do PP em relação ao grupo INT, porém inferior ao observado no grupo tratado com BZ. A maioria dos grupos tratados não apresentou 100% de negatividade na HC e PCR simultaneamente, entretanto o grupo tratado com BZ apresentou 57,1% de cura com sobrevida de 87,5%, seguido por GZL 3 mg/kg/dia IV que curou 12,5% dos animais com sobrevida de 100%. Este resultado, em particular, aliado aos demais, representam uma boa perspectiva do uso da GZL para o tratamento da DCh a ser explorada.
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    Efficacy of Lychnopholide polymeric nanocapsules after oral and intravenous administration in murine experimental Chagas disease.
    (2016) Mello, Carlos Geraldo Campos de; Branquinho, Renata Tupinambá; Oliveira, Maykon Tavares de; Milagre, Matheus Marques; Guimarães, Dênia Antunes Saúde; Mosqueira, Vanessa Carla Furtado; Lana, Marta de
    The etiological treatment of Chagas disease remains neglected. The compounds available show several limitations, mainly during the chronic phase. Lychnopholide encapsulated in polymeric nanocapsules (LYC-NC) was efficacious in mice infected with Trypanosoma cruzi and treated by intravenous administration during the acute phase (AP). As the oral route is preferred for treatment of chronic infections, such as Chagas disease, this study evaluated the use of oral LYC-NC in the AP and also compared it with LYC-NC administered to mice by the oral and intravenous routes during the chronic phase (CP). The therapeutic efficacy was evaluated by fresh blood examination, hemoculture, PCR, and enzyme-linked immunosorbent assay (ELISA). The cure rates in the AP and CP were 62.5% and 55.6%, respectively, upon oral administration of LYC–poly(D,L-lactide)–polyethylene glycol nanocapsules (LYC-PLA-PEG-NC) and 57.0% and 30.0%, respectively, with LYC–poly- -caprolactone nanocapsules (LYC-PCL-NC). These cure rates were significantly higher than that of free LYC, which did not cure any animals. LYC-NC formulations administered orally during the AP showed cure rates similar to that of benznidazole, but only LYC-NC cured mice in the CP. Similar results were achieved with intravenous treatment during the CP. The higher cure rates obtained with LYC loaded in PLA-PEG-NC may be due to the smaller particle size of these NC and the presence of PEG, which influence tissue diffusion and the controlled release of LYC. Furthermore, PLA-PEG-NC may improve the stability of the drug in the gastrointestinal tract. This work is the first report of cure of experimental Chagas disease via oral administration during the CP. These findings represent a new and important perspective for oral treatment of Chagas disease.
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    Evaluation of the anti-Trypanosoma cruzi activity in vitro and in vivo of silibinin and silibinin in association to benznidazole.
    (2020) Torchelsen, Fernanda Karoline Vieira da Silva; Silva, Thaila Martins; Milagre, Matheus Marques; Silva, Rafael Rodrigues; Reis, Levi Eduardo Soares; Branquinho, Renata Tupinambá; Silva, Glenda Nicioli da; Lana, Marta de
    Chagas disease (CD) is endemic in Latin America. Drugs available for its treatment are benznidazole (BZ)/nifurtimox (NF), both with low efficacy in the late infection and responsible for several side effects. Studies of new drugs for CD among natural products, and using drug combinations with BZ/NF are recommended. Silibinin (SLB) is a natural compound that inhibits the efflux pump (Pgp) of drugs in host cell membranes, causes death of trypanosomatids, has anti-inflammatory activity, and was never assayed against T. cruzi. Here, in vitro and in vivo activities of SLB, SLB+BZ, and BZ against T. cruzi Y strain were evaluated. Cytotoxicity of SLB in VERO cells by the MTT method revealed IC50 of 250.22 μM. The trypanocidal activity evaluated by resazurin method in epimastigotes showed that SLB 25 μM inhibited parasite growth. SLB IC50 and selectivity index (SI) for amastigote were 79.81 μM and 3.13, respectively. SLB100+BZ10 showed higher parasite inhibition (91.44%) than SLB or BZ. Swiss mice infected with Y strain were treated with SLB, SLB+BZ, and BZ. Parasitemia was evaluated daily and 90, 180, and 240 days after treatment in surviving animals by hemoculture, blood qPCR, and after euthanasia, by qPCR in heart tissue. SLB monotherapy was not able to control the parasitemia/mortality of the animals. Parasitological negativation of 85.7– 100% was observed in the experimental groups treated with SLB+BZ. Although SLB had shown activity against T. cruzi in vitro, it was not active in mice. Thus, the results of the therapeutic effect observed with SLB+BZ may be interpreted as a result from BZ action.
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    Increased body exposure to new anti-trypanosomal through nanoencapsulation.
    (2017) Branquinho, Renata Tupinambá; Lana, Gwenaelle Elza Nathalie Pound; Milagre, Matheus Marques; Guimarães, Dênia Antunes Saúde; Vilela, José Mário Carneiro; Andrade, Margareth Spangler; Lana, Marta de; Mosqueira, Vanessa Carla Furtado
    Lychnopholide, a lipophilic sesquiterpene lactone, is efficacious in mice at the acute and chronic phases of Chagas disease. Conventional poly-ε-caprolactone (PCL) and long-circulating poly(D,L-lactide)-block-polyethylene glycol (PLA-PEG) nanocapsules containing lychnopholide were developed and characterized. Lychnopholide presented high association efficiency (>90%) with the nanocapsules. A new, fast and simple HPLC-UV-based bioanalytical method was developed, validated in mouse plasma and applied to lychnopholide quantification in in vitro release kinetics and pharmacokinetics. The nanocapsules had mean hydrodynamic diameters in the range of 100–250 nm, negative zeta potentials (−30 mV to −57 mV), with good physical stability under storage. Atomic force microscopy morphological analysis revealed spherical monodispersed particles and the absence of lychnopholide crystallization or aggregation. Association of lychnopholide to PLA-PEG nanocapsules resulted in a 16-fold increase in body exposure, a 26-fold increase in plasma half-life and a dramatic reduction of the lychnopholide plasma clearance (17-fold) in comparison with free lychnopholide. The improved pharmacokinetic profile of lychnopholide in long-circulating nanocapsules is in agreement with the previously reported improved efficacy observed in Trypanosoma cruzi-infected mice. The present lychnopholide intravenous dosage form showed great potential for further pre-clinical and clinical studies in Chagas disease and cancer therapies.