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1.
Parasitol Res ; 121(2): 775-780, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35048211

RESUMO

Characterized as an acute and chronic parasitic disease, schistosomiasis mansoni has as its central pathology the formation of hepatic granulomas in response to the parasite's eggs trapped in the host's liver. In recent years, research on propolis has grown; however, there is little anthelmintic work on this bee product. In the propolis scenario, Brazilian ones receive attention, with green and red propolis standing out. This study aims to evaluate in vivo the standardized extract of Brazilian green propolis (Pex) against Schistosoma mansoni. The in vivo antiparasitic activity of Pex was conducted in female BALB/c mice infected with S. mansoni and of the three groups treated with Pex (300 mg/kg); G2 (35th to 42nd dpi) reduced the total worm burden by 55.32%, followed by G3 (42nd to 49th dpi) and G4 (49th to 56th dpi), with about 46%. Furthermore, G2 significantly reduced the total egg load in the ileum (59.33%) and showed an increase in the dead eggs. Similarly, histological analysis of the livers showed a significant reduction in the number and diameter of the granulomas. Based on these results, there is an interesting schistosomicidal activity of Pex and its potential against the formation of hepatic granulomas, paving the way for more detailed studies of propolis in the animal model of schistosomiasis mansoni.


Assuntos
Própole , Esquistossomose mansoni , Animais , Modelos Animais de Doenças , Feminino , Granuloma/tratamento farmacológico , Fígado , Camundongos , Camundongos Endogâmicos BALB C , Schistosoma mansoni , Esquistossomose mansoni/tratamento farmacológico
2.
Nat Prod Res ; : 1-7, 2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-34963393

RESUMO

Lignan dinitrohinokinin displays important biological activities, which led to the preparation of its poly-ε-caprolactone nanoparticles. Kinetics analysis revealed initially slow drug release followed by a prolonged, moderate release 6 h later due to DNHK diffusion through the polymeric matrix. Molecular dynamics simulations show that DNHK molecules that interact stronger with other DNHK molecules near the PCL/DNHK surface are more difficult to dissociate from the nanoparticle. The smaller diameter nanocapsules with negative surface charge conferred good colloidal stability. The formulations showed a size distribution with monodisperse systems formation. In vivo evaluation of schistosomicidal activity against Schistosoma mansoni showed that DNHK, when incorporated into nanoparticles, caused egg number reduction of 4.2% and 28.1% at 40 mg/kg and 94.2% and 84.4% at 400 mg/kg in the liver and the spleen, respectively. The PCL nanoparticles were stable in aqueous dispersion and could be optimized to be used as a promising lignan release agent.

3.
Nat Prod Res ; : 1-8, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34736364

RESUMO

This work aimed to synthesize poly (D, L-lactic-co-glycolic acid) (PLGA) microparticles containing hinokinin (HNK) and to evaluate their cytotoxic activity against tumoral SiHa cells and non-tumoral HaCaT cells. Hinokinin was incorporated into PLGA (PLGA-HNK) with an encapsulation efficiency of 84.18 ± 2.32%. PLGA and PLGA-HNK were characterized by SEM microscopy and showed spherical morphology with an average size of ∼3.33. Encapsulation efficiency was determined by a calibration curve using UV-vis spectroscopy. PLGA-HNK more active inhibiting proliferation of SiHa cells (IC50 = 14.68 µM) than free HNK (IC50 = 225.5 µM). In relation to HaCaT cells, PLGA-HNK showed no significant difference compared to the negative control. These results led to an increase in HNK bioavailability and thereby, biological activity. In silico prediction analysis suggests that HNK is cytotoxic against SiHa cells with E6 and MDM2 inhibition as possible main mechanism of action.

4.
Nat Prod Res ; : 1-4, 2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34647494

RESUMO

bicyclic [3.2.1] octane neolignans have garnered increasing interest, because of their unique structural features and biological activities. This study describes the isolation and identification of a new bicyclic octane neolignan 1 obtained through fractionation of the crude extract of the stem of Aniba firmula (Lauraceae family). The structure of bicyclic octane neolignan 1 was determined through NMR analysis and mass spectrometry data.

5.
Nat Prod Res ; : 1-6, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34498969

RESUMO

Cholinesterase (ChE) inhibitors are currently the main drugs used to treat the cognitive symptoms of Alzheimer's disease (AD). Dual cholinesterase inhibitors, that is, compounds capable of inhibiting both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), are considered a new potential approach for the long-term treatment of patients with AD. We evaluated the ethyl acetate extract of Phomopsis sp., grown in liquid medium malt extract and potato dextrose (PDB), an endophyte isolated from the Brazilian medicinal plant Hancornia speciosa. The anticholinesterase (AChE) and butyrylcholinesterase (BuChE) activities were evaluated. The extracts exhibited dual action against AChE and BuChE. The compounds isolated from these extracts, nectriapyrone (1) and tryptophol (2), showed inhibitory action on BuChE (IC50 = 29.05 and 34.15 µM respectively), being selective towards BuChE. The discovery of selective BuChE inhibitors is extremely important for the development of drugs that can be used in the treatment of patients diagnosed with AD.

6.
Chem Biodivers ; 18(9): e2100310, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34231306

RESUMO

Propolis is a bee product that has been used in medicine since ancient times. Although its anti-inflammatory, antioxidant, antimicrobial, antitumor, and immunomodulatory activities have been investigated, its anti-parasitic properties remain poorly explored, especially regarding helminths. This review surveys the results obtained with propolis around the world against human parasites. Regarding protozoa, studies carried out with the protozoa Trypanosoma spp. and Leishmania spp. have demonstrated promising results in vitro and in vivo. However, there are fewer studies for Plasmodium spp., the etiological agent of malaria and less so for helminths, particularly for Fasciola spp. and Schistosoma spp. Despite the favorable in vitro results with propolis, helminth assays need to be further investigated. However, propolis has shown itself to be an excellent natural product for parasitology, thus opening new paths and approaches in its activity against protozoa and helminths.


Assuntos
Antiparasitários/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Própole/química , Animais , Antiparasitários/química , Antiparasitários/isolamento & purificação , Brasil , Helmintos/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plasmodium/efeitos dos fármacos , Trypanosoma/efeitos dos fármacos
7.
Bioorg Chem ; 105: 104402, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33130347

RESUMO

ATP-Binding Cassette (ABC) transporters are the main class of transmembrane transporters involved in pathogenic fungal resistance against chemotherapeutic agents. Herein we report results which show that batzelladine D (1) and norbatzelladine L (2) reverse the fluconazole resistance phenotype mediated by Pdr5p transporter on Saccharomyces cerevisiae. Both alkaloids were able to chemosensitize the Pdr5p-overexpressing strain by synergistic interaction with fluconazole. Both compounds also showed an inhibitory effect on the catalytic activity and on the intracellular accumulation of rhodamine 6G, and did not show significant in vitro mammalian cells toxicity.


Assuntos
Alcaloides/farmacologia , Fluconazol/farmacologia , Poríferos/química , Pirimidinas/farmacologia , Rodaminas/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/metabolismo , Alcaloides/química , Alcaloides/isolamento & purificação , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Camundongos , Estrutura Molecular , Pirimidinas/química , Pirimidinas/isolamento & purificação , Rodaminas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Relação Estrutura-Atividade
8.
Chem Biodivers ; 17(9): e2000277, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32578329

RESUMO

The chemotherapy of schistosomiasis remains centered in the use of praziquantel, however, there has been growing resistant parasites to this drug. Thus, the aim of this work was to evaluate in vitro schistosomicidal activity of the hexanes/dichloromethane 1 : 1 extract of Brazilian green propolis (Pex), as well as its major isolated compounds artepillin C, caffeic acid, coumaric acid and drupanin against Schistosoma mansoni. The Pex was active by displaying an IC50 value of 36.60 (26.26-51.13) µg mL-1 at 72 h against adult worms of S. mansoni. The major isolated compounds were inactive with IC50 values >100 µM, however, the combination of the isolated compounds (CM) in the same range found in the extract was active with an IC50 value of 41.17 (39.89-42.46) µg mL-1 at 72 h. Pex and CM induced alteration in the tegument of S. mansoni, and caffeic acid caused alteration in egg's maturation. Pex displayed in vitro activity against adult worms' and eggs' viability of S. mansoni, which opens new perspectives to better understand the synergistic and/or additive effects promoted by both Pex extract and CM against schistosomiasis features.


Assuntos
Própole/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Brasil , Relação Dose-Resposta a Droga , Estrutura Molecular , Fenótipo , Própole/química , Própole/isolamento & purificação , Relação Estrutura-Atividade
9.
Molecules ; 24(23)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795429

RESUMO

Metabolomics approaches have become fundamental strategies for the analysis of complex mixtures, guiding the isolation of target compounds by focusing on unpublished or promising pharmacological properties. The discovery of novel anti-inflammatory agents is important due to several limitations regarding their potency, efficacy, and adverse effects. Thus, novel anti-inflammatory candidates are essential, aiming to find agents with better mechanisms of action. In this context, extracts from Poincianella pluviosa var. peltophoroides demonstrated significant in vivo anti-inflammatory potential. Thus, metabolomics analysis based on UHPLC-UV-HRFTMS data was performed for the identification of biomarkers with anti-inflammatory properties. Metabolomics-guided chromatographic process led to the isolation of novel compounds 4‴-methoxycaesalpinioflavone and 7-methoxycaesalpinioflavone, as well as known derivatives rhuschalcone VI and caesalpinioflavone. Isolated compounds caused edema inhibition and neutrophil recruitment. Two of them showed better efficacy than reference drugs (indomethacin and dexamethasone). Results of in vivo experiments corroborated those obtained through metabolomics and statistical analyses guiding the isolation of substances of interest.


Assuntos
Anti-Inflamatórios/farmacologia , Edema/tratamento farmacológico , Fabaceae/química , Metabolômica , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Edema/imunologia , Edema/patologia , Masculino , Camundongos , Neutrófilos/patologia , Extratos Vegetais/química
10.
J Nat Prod ; 80(3): 720-725, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28191951

RESUMO

Marine sponges are a rich source of terpenoids with rearranged spongian carbon skeletons. Investigation of extracts from the sponge Darwinella cf. oxeata yielded four new rearranged diterpenoids, oxeatine (2) and oxeatamides H-J (3-5), as well as the known metabolites oxeatamide A (6), oxeatamide A methyl ester (7), and membranolide (1). Oxeatine (2) has a new heterocyclic skeleton, while oxeatamide J (5) has an N-methyl urea group included in a γ-lactam moiety. UPLC-QTOF analysis of the extract obtained from the mantle of the nudibranch Felimida grahami indicated the presence of 1 and 4.


Assuntos
Diterpenos/química , Diterpenos/isolamento & purificação , Gastrópodes/química , Poríferos/química , Terpenos/química , Terpenos/isolamento & purificação , Animais , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
11.
J Nat Prod ; 79(6): 1668-78, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27227682

RESUMO

Application of a refined procedure of experimental design and chemometric analysis to improve the production of curvularin-related polyketides by a marine-derived Penicillium sp. DRF2 resulted in the isolation and identification of cyclothiocurvularins 6-8 and cyclosulfoxicurvularins 10 and 11, novel curvularins condensed with a mercaptolactate residue. Two additional new curvularins, 3 and 4, are also reported. The structures of the sulfur-bearing curvularins were unambiguously established by analysis of spectroscopic data and by X-ray diffraction analysis. Analysis of stable isotope feeding experiments with [U-(13)C3(15)N]-l-cysteine confirmed the presence of the 2-hydroxy-3-mercaptopropanoic acid residue in 6-8 and the oxidized sulfoxide in 10 and 11. Cyclothiocurvularins A (6) and B (7) are formed by spontaneous reaction between 10,11-dehydrocurvularin (2) and mercaptopyruvate (12) obtained by transamination of cysteine. High ratios of [U-(13)C3(15)N]-l-cysteine incorporation into cyclothiocurvularin B (7), the isolation of two diastereomers of cyclothiocurvularins, the lack of cytotoxicity of cyclothiocurvularin B (7) and its methyl ester (8), and the spontaneous formation of cyclothiocurvularins from 10,11-dehydrocurvularin and mercaptopyruvate provide evidence that the formation of cyclothiocurvularins may well correspond to a 10,11-dehydrocurvularin detoxification process by Penicillium sp. DRF2.


Assuntos
Penicillium/química , Policetídeos/isolamento & purificação , Cristalografia por Raios X , Cisteína , Ensaios de Seleção de Medicamentos Antitumorais , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Policetídeos/química , Policetídeos/farmacologia , Estereoisomerismo , Zearalenona/análogos & derivados , Zearalenona/química
12.
Org Lett ; 17(21): 5152-5, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26444492

RESUMO

The structure of the fungal metabolite roussoellatide (1) has been established by spectroscopic and X-ray diffraction analyses. Results from feeding experiments with [1-(13)C]acetate, [2-(13)C]acetate, and [1,2-(13)C]acetate were consistent with a biosynthetic pathway to the unprecedented skeleton of 1 involving Favorskii rearrangements in separate pentaketides, subsequently joined via an intermolecular Diels-Alder reaction.


Assuntos
Ascomicetos/química , Hidrocarbonetos Clorados/síntese química , Policetídeos/síntese química , Cristalografia por Raios X , Reação de Cicloadição , Hidrocarbonetos Clorados/química , Biologia Marinha , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Policetídeos/química
13.
J Nat Prod ; 78(5): 1101-12, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25924111

RESUMO

HPLC-UV-ELSD-MS-guided fractionation of the anti-parasitic extract obtained from the marine sponge Monanchora arbuscula, collected off the southeastern coast of Brazil, led to the isolation of a series of guanidine and pyrimidine alkaloids. The pyrimidines monalidine A (1) and arbusculidine A (7), as well as the guanidine alkaloids batzellamide A (8) and hemibatzelladines 9-11, represent new minor constituents that were identified by analysis of spectroscopic data. The total synthesis of monalidine A confirmed its structure. Arbusculidine A (7), related to the ptilocaulin/mirabilin/netamine family of tricyclic guanidine alkaloids, is the first in this family to possess a benzene ring. Batzellamide A (8) and hemibatzelladines 9-11 represent new carbon skeletons that are related to the batzelladines. Evaluation of the anti-parasitic activity of the major known metabolites, batzelladines D (12), F (13), L (14), and nor-L (15), as well as of synthetic monalidine A (1), against Trypanosoma cruzi and Leishmania infantum is also reported, along with a detailed investigation of parasite cell-death pathways promoted by batzelladine L (14) and norbatzelladine L (15).


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Guanidinas/isolamento & purificação , Guanidinas/farmacologia , Poríferos/química , Pirimidinas/isolamento & purificação , Pirimidinas/farmacologia , Alcaloides/química , Animais , Brasil , Guanidinas/química , Leishmania infantum/efeitos dos fármacos , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Testes de Sensibilidade Parasitária , Pirimidinas/química , Trypanosoma cruzi/efeitos dos fármacos
14.
Nat Prod Commun ; 9(1): 33-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24660456

RESUMO

Contamination of preharvest and stored peanuts (Arachis hypogaea L.) by aflatoxigenic strains of Aspergillus flavus is an important economical and food safety problem in many tropical and subtropical areas of the world. The present investigation reports the antifungal activity of a halitoxins/amphitoxins enriched extract obtained from the sponge Amphimedon sp. (HAEEAsp), and of batzelladine L isolated from the sponge Monanchora arbuscula on Aspergillus flavus isolated from stored peanuts. A PCR system directed against the ITS region and aflatoxin biosynthetic pathway genes of A. flavus was applied for identification of aflatoxin producing strains. The HAEEAsp extract and batzelladine L showed minimal inhibitory concentration (MIC) in the range between 1.9 to 15.6 microg/mL and between 1.9 to 7.8 microg/mL, respectively. The minimal fungicide concentration (MFC) of HAEEAsp extract and batzelladine L was in the range between 3.9 to 31.3 microg/mL and 3.9 to 15.6 microg/mL, respectively. These results indicate that these marine alkaloids may be further explored for the development of potential lead compounds active against aflatoxigenic fungi.


Assuntos
Antifúngicos/análise , Aspergillus flavus/efeitos dos fármacos , Poríferos/química , Animais , Antifúngicos/farmacologia , Arachis/microbiologia , Testes de Sensibilidade Microbiana , Poríferos/metabolismo
15.
Nat Prod Rep ; 29(12): 1382-406, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22991131

RESUMO

The chemistry and biology of organic natural guanidines are reviewed, including the isolation, structure determination, synthesis, biosynthesis and biological activities of alkaloids, non-ribosomal peptides, guanidine-bearing terpenes, polyketides and shikimic acid derivatives from natural sources.


Assuntos
Produtos Biológicos , Guanidinas , Animais , Bactérias/química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Guanidinas/química , Guanidinas/isolamento & purificação , Guanidinas/farmacologia , Invertebrados/química , Estrutura Molecular , Plantas Medicinais/química , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/farmacologia , Terpenos/química , Terpenos/isolamento & purificação , Terpenos/farmacologia
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