DEFAR - Departamento de Farmácia

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530

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2015 - 201922020 - 20221

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Autor: search.filters.author.Vale, Valdicley VieiraTem arquivos: Sim

Resultados da Pesquisa

Agora exibindo 1 - 3 de 3
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    Activity of alkaloids from Aspidosperma nitidum against Leishmania (Leishmania) amazonensis.
    (2022) Veiga, Andreza do Socorro Silva da; Silveira, Fernando Tobias; Silva, Edilene Oliveira da; Diniz Júnior, José Antônio Picanço; Araújo, Sanderson Corrêa; Campos, Marliane Batista; Marinho, Andrey Moacir do Rosário; Brandão, Geraldo Célio; Vale, Valdicley Vieira; Percário, Sandro; Dolabela, Maria Fâni
    This study evaluated the morphological changes caused by fractions and subfractions, obtained from barks of Aspidosperna nitidum, against L. (L.) amazonensis promastigotes. The ethanolic extract (EE) obtained through the maceration of trunk barks was subjected to an acid–base partition, resulting the neutral (FN) and the alkaloid (FA) fractions, and fractionation under refux, yielded hexane (FrHEX), dichloromethane (FrDCL), ethyl acetate (FrACoET), and methanol (FrMEOH) fractions. The FA was fractionated and three subfractions (SF5-6, SF8, and SF9) were obtained and analyzed by HPLC–DAD and 1 H NMR. The antipromastigote activity of all samples was evaluated by MTT, after that, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for the active fractions were performed. Chromatographic analyzes suggest the presence of alkaloids in EE, FN, FA, and FrDCL. The fractionation of FA led to the isolation of the indole alkaloid dihydrocorynantheol (SF8 fractions). The SF5-6, dihydrocorynantheol and SF-9 samples were active against promastigotes, while FrDCL was moderately active. The SEM analysis revealed cell rounding and changes in the fagellum of the parasites. In the TEM analysis, the treated promastigotes showed changes in fagellar pocket and kinetoplast, and presence of lipid inclusions. These results suggest that alkaloids isolated from A. nitidum are promising as leishmanicidal.
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    Himatanthus bracteatus stem extracts present antiflavivirus activity while an isolated sesquiterpene glucoside present only anti-Zika virus activity in vitro.
    (2019) Silva, Marlene Lourenço da; Stehmann, João Renato; Serafim, Mateus Sá Magalhães; Vale, Valdicley Vieira; Gontijo, Douglas da Costa; Brandão, Geraldo Célio; Kroon, Erna Geessien; Oliveira, Alaíde Braga de
    The hexane and ethanol extracts from Himatanthus bracteatus (Apocynaceae) stems were evaluated for antiviral activity against Zika virus, yellow fever virus and dengue virus 2 and for cytotoxicity in Vero cells by MTT assay. The ethanol extract showed good antiviral activity against the three viruses with selective indexes (SI) > 10 and its fractionation led to the isolation of the known plumieride that was active only against Zika virus (SI of 15.97).
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    Anti-malarial activity and toxicity assessment of Himatanthus articulatus, a plant used to treat malaria in the Brazilian Amazon.
    (2015) Vale, Valdicley Vieira; Vilhena, Thyago da Costa; Trindade, Rafaela Cabral dos Santos; Ferreira, Marlia Regina Coelho; Percário, Sandro; Soares, Luciana Ferreira; Pereira, Washington Luiz Assunção; Brandão, Geraldo Célio; Oliveira, Alaíde Braga de; Dolabela, Maria Fâni; Vasconcelos, Flávio de
    Background: Plasmodium falciparum has become resistant to some of the available drugs. Several plant species are used for the treatment of malaria, such as Himatanthus articulatus in parts of Brazil. The present paper reports the phyto-chemistry, the anti-plasmodial and anti-malarial activity, as well as the toxicity of H. articulatus. Methods: Ethanol and dichloromethane extracts were obtained from the powder of stem barks of H. articulates and later fractionated and analysed. The anti-plasmodial activity was assessed against a chloroquine resistant strain P. falciparum (W2) in vitro, whilst in vivo anti-malarial activity against Plasmodium berghei (ANKA strain) was tested in mice, evaluating the role of oxidative stress (total antioxidant capacity - TEAC; lipid peroxidation – TBARS, and nitrites and nitrates - NN). In addition, cytotoxicity was evaluated using the HepG2 A16 cell-line. The acute oral and sub-chronic toxicity of the ethanol extract were evaluated in both male and female mice. Results: Plumieride was isolated from the ethyl acetate fraction of ethanol extract, Only the dichloromethane extract was active against clone W2. Nevertheless, both extracts reduced parasitaemia in P. berghei-infected mice. Besides, a significant reduction in pulmonary and cerebral levels of NN (nitrites and nitrates) was found, as well as in pulmonary TBARS, indicating a reduced oxidative damage to these organs. The ethanol extract showed low cytotoxicity to HepG2 A16 cells in the concentrations used. No significant changes were observed in the in vivo toxicity studies. Conclusions: The ethanol extract of H. articulatus proved to be promising as anti-malarial medicine and showed low toxicity.