DEFAR - Departamento de Farmácia
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/530
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Resultados da Pesquisa
Item Virucidal antiviral activity of Maytenus quadrangulata extract against Mayaro virus : evidence for the presence of catechins.(2023) Nunes, Damiana Antônia de Fátima; Lopes, Gabriela Francine Martins; Nizer, Waleska Stephanie da Cruz; Aguilar, Mariana Guerra de; Santos, Felipe Rocha da Silva; Sousa, Grasiely Faria de; Ferraz, Ariane Coelho; Duarte, Lucienir Pains; Brandão, Geraldo Célio; Vieira Filho, Sidney Augusto; Magalhães, Cíntia Lopes de Brito; Ferreira, Jaqueline Maria Siqueira; Magalhães, José Carlos deEthnopharmacological relevance: Mayaro virus (MAYV) is an arbovirus endemic to the Amazon region, which comprises the states of the North and Midwest region of Brazil and encompasses the largest tropical forest in the world, the Amazon Forest. The confirmation of its potential transmission by Aedes aegypti and recent cases in Brazil, mainly in large centers in the northern region, led to the classification of Mayaro fever as an emerging disease. Traditional medicine is commonly used to treat various diseases, mainly by local riverside populations. Some species of the genus Maytenus, which have similar morphologies, are popularly used to treat infections and inflammations. In this context, our research group has studied and confirmed the antiviral activity of several plant-derived compounds. However, several species of this same genus have not been studied and therefore deserve attention. Aim of the study: This study aimed to demonstrate the effects of ethyl acetate extracts of leaves (LAE) and branches (TAE) of Maytenus quadrangulata against MAYV. Materials and methods: Mammalian cells (Vero cells) were used to evaluate the cytotoxicity of the extracts. After cell infection by MAYV and the treatment with the extracts, we evaluated the selectivity index (SI), the virucidal effect, viral adsorption and internalization, and the effect on viral gene expression. The antiviral action was confirmed by quantifying the viral genome using RT-qPCR and by analyzing the effect on virus yield in infected cells. The treatment was performed based on the effective concentration protective for 50% of the infected cells (EC50). Results: The leaves (LAE; EC50 12.0 μg/mL) and branches (TAE; EC50 101.0 μg/mL) extracts showed significative selectivity against the virus, with SI values of 79.21 and 9.91, respectively, which were considered safe. Phytochemical analysis revealed that the antiviral action was associated with the presence of catechins, mainly in LAE. This extract was chosen for the subsequent studies since it reduced the viral cytopathic effect and virus production, even at high viral loads [MOI (multiplicity of infection) 1 and 5]. The effects of LAE resulted in a marked reduction in viral gene expression. The viral title was drastically reduced when LAE was added to the virus before infection or during replication stages, reducing virus production up to 5-log units compared to infected and untreated cells.Item Efficacy of nanoemulsion with Pterodon emarginatus Vogel oleoresin for topical treatment of cutaneous leishmaniasis.(2021) Kawakami, Monique Yoko Martins; Zamora, Lisset Ortiz; Araújo, Raquel Silva; Fernandes, Caio Pinho; Ricotta, Tiago Queiroga Nery; Oliveira, Leandro G. de; Queiroz Júnior, Celso Martins; Fernandes, Ana Paula Salles Moura; Conceição, Edemilson Cardoso da; Ferreira, Lucas Antônio Miranda; Barros, André Luís Branco de; Aguiar, Marta Marques Gontijo de; Oliveira, Anna Eliza Maciel de Faria MotaCutaneous leishmaniasis (CL) is a neglected tropical skin disease caused by the protozoan genus Leishmania. The treatment is restricted to a handful number of drugs that exhibit toxic effects, limited efficacy, and drug resis- tance. Additionally, developing an effective topical treatment is still an enormous unmet medical challenge. Natural oils, e.g. the oleoresin from P. emarginatus fruits (SO), contain various bioactive molecules, especially terpenoid compounds such as diterpenes and sesquiterpenes. However, its use in topical formulations can be impaired due to the natural barrier of the skin for low water solubility compounds. Nanoemulsions (NE) are drug delivery systems able to increase penetration of lipophilic compounds throughout the skin, improving their topical effect. In this context, we propose the use of SO-containing NE (SO-NE) for CL treatment. The SO-NE was produced by a low energy method and presented suitable physicochemical characteristic: average diameter and polydispersity index lower than 180 nm and 0.2, respectively. Leishmania (Leishmania) amazonensis-infected BALB/c mice were given topical doses of SO or SO-NE. The topical use of a combination of SO-NE and intra- peritoneal meglumine antimoniate reduced lesion size by 41 % and tissue regeneration was proven by histo- pathological analyses. In addition, a reduction in the parasitic load and decreased in the level of IFN-γ in the lesion may be associated, as well as a lower level of the cytokine IL-10 may be associated with a less intense inflammatory process. The present study suggests that SO-NE in combination meglumine antimoniate represents a promising alternative for the topical treatment of CL caused by L. (L.) amazonensis.Item Validation of a colorimetric assay for the in vitro screening of inhibitors of angiotensin-converting enzyme (ACE) from plant extracts.(2005) Serra, Carla Penido; Côrtes, Steyner de França; Lombardi, Júlio Antônio; Oliveira, Alaíde Braga de; Braga, Fernão CastroAnew method for the in vitro screening of plant extracts with potential angiotensin-converting enzyme (ACE) inhibitory activity is proposed. The method is based on the cleavage of the substrate hippuryl-glycyl-glycine by ACE and subsequent reaction with trinitrobenzenesulfonic acid to form 2,4,6-trinitrophenyl-glycyl-glycine, whose absorbance is determined at 415nm in a microtitre plate reader. Rabbit lung dehydrated by acetone was employed as an enzyme source. Validation of the method showed satisfactory intra-day (CV ¼ 7.63%) and inter-day precision (CV ¼ 13.61%), recovery (97–102.1%), sensitivity (IC50 ¼ 14.1 nmol/l) and linearity in the range 7.5–120 mmol/l of glycyl-glycine (r2 ¼ 0:9921). Besides, the method showed good correlation with a HPLC assay already established for the screening of ACE inhibitors (r ¼ 0:9935 and 0:9034; respectively, for captopril solutions and for plant extracts). The method involves only inexpensive reagents and apparatus.