Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Food Funct ; 13(14): 7591-7613, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35731546

RESUMO

The therapeutic virtues of honey no longer need to be proven. Honey, which is rich in nutrients, is an excellent nutritional food because of its many properties; however, honey has been diverted from this primary function and used in clinical research. Evidence has shown that honey still possesses unknown properties and some of these aspects have never been addressed. In this work, two bioactive compounds found in honey (methylglyoxal and antimicrobial peptides) were evaluated for their anti-Bacillus subtilis activity with particular attention to their dilution factor. Although this bacterial strain does not possess an indigenous virulence factor gene, it becomes virulent by transferring plasmids with B. thuringiensis or expression of toxins from Bordetella pertussis. As is known, methylglyoxal is a toxic electrophile present in many eukaryotic and prokaryotic cells, which is generated by enzymatic and non-enzymatic reactions. Its overexpression successfully kills bacteria by inducing membrane disruption. Also, AMPs show potent inhibitory action against Gram-positive bacteria. Because of the lack of information concerning the main ingredients of honey, the microencapsulation process was used. Both methylglyoxal (MGO) and peptide-loaded liposomes were synthesized, characterized and compared to their free forms. The liposomal formulations contained a mixture of eggPC, cholesterol, and octadecylamine and their particle sizes were measured and their encapsulation efficacy calculated. The results revealed that Algerian multifloral white honey contained higher levels of MGO compared to manuka honey, which prevented bacterial growth and free MGO was relatively less effective. In fact, MGO killed BS in the loaded form with the same bacteriostatic and bactericidal index. However, the action of AMPs was different. Indeed, the investigation into the reactivity of MGO in the solvent indicated that regardless of the level of water added, honey is active at a fixed dilution. This data introduces the notion of dilution and abolishes the concept of concentration. Moreover, the synergistic antibacterial effect of the compounds in honey was diminished by the matrix effect. The degree of liposome-bacteria-fusion and the delay effect observed could be explain by both the composition and nature of the lipids used. Finally, this study reinforces the idea that under certain conditions, the metalloproteinases in honey produce AMPs.


Assuntos
Mel , Antibacterianos/farmacologia , Bacillus subtilis , Lipossomos , Óxido de Magnésio , Peptídeos , Aldeído Pirúvico/química
2.
Chem Biol Interact ; 345: 109511, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-33989593

RESUMO

Methylglyoxal is a dicarbonyl compound recruited as a potential cytotoxic marker, initially presents in cells and considered as a metabolite of the glycolytic pathway. Our aim is to demonstrate the inhibitory effect of 3, 3'-[3-(5-chloro-2-hydroxyphenyl)-3-oxopropane-1, 1-diyl] Bis (4-hydroxycoumarin) on the glyoxalase system, and indirectly its anticancer activity. The docking of OT-55 was conducted by using Flexible docking protocol, ChiFlex and libdock tools inside the active site of Glo-I indicated that both hydrogen bonding and hydrophobic interactions contributed significantly in establishing potent binding with the active site which is selected as a strong inhibitor with high scoring values and maximum Gibbs free energy. Coumarin-liposome formulation was characterized and evaluated in vivo against chemically induced hepatocarcinoma in Wistar rats. After Diethylnitrosamine (DEN) induction, microscopic assessment was realized; precancerous lesions were developed showing an increase of both tumor-associated lymphocyte and multiple tumor acini supported by the blood investigation. Our finding also suggested a preferential uptake of liposomes respectively in liver, kidney, lung, brain and spleen in the DEN-treated animals. OT-55 has also been shown to inhibit the activity of Glo-I in vitro as well as in DEN-treated rats. An abnormal high level of MGO of up to 50% was recorded followed by a reduction in glucose consumption and lactate dehydrogenase production validated in the positive control. MGO generates apoptosis as depicted by focal hepatic lesions. Also, no deleterious effects in the control group were observed after testing our coumarin but rather a vascular reorganization leading to nodular regenerative hyperplasia. Involved in the detoxification process, liver GSH is restored in intoxicated rats, while no changes are seen between controls. At the endothelial cell, OT-55 appears to modulate the release of NO only in the DEN-treated group. OT-55 would behave both as an anticancer agent but also as an angiogenic factor regarding results obtained.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Espaço Intracelular/efeitos dos fármacos , Lactoilglutationa Liase/antagonistas & inibidores , Neoplasias Hepáticas/patologia , Modelos Moleculares , Aldeído Pirúvico/metabolismo , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transporte Biológico , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Espaço Intracelular/metabolismo , Lactoilglutationa Liase/química , Lactoilglutationa Liase/metabolismo , Lipossomos/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Terapia de Alvo Molecular , Conformação Proteica , Ratos , Ratos Wistar , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Biochimie ; 168: 169-184, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707099

RESUMO

Two analytical methods; high performance liquid chromatography and gas chromatography were used to determine the content of 2-methylquinoxaline, a methylglyoxal-derived agent in sera from cattle with fascioliasis. Methylglyoxal is a highly mutagenic and cytotoxic reactive dicarbonyl compound formed by non-enzymatic fragmentation of triose phosphate GAP and DHAP during glycolysis which regularly contributes to repositioning the energetic balance between physiological and pathological situations. The aim of this study was to propose the MGO as a new biomarker in the bovine fasciolosis. Strongly infected animals showed a correlation between the relatively high levels of Fasciola hepatica anti-f2 antibody and methylglyoxal compared to unharmed animals. Also, an acute hyperglycemia was recorded and closely related to hepatic parenchyma hyperplasia, inflammation, bile ducts obstruction and scléro-fibrous foci formation.Unlike HPLC, which has shown analytical flaws and irregularities, GC-MS remains an excellent diagnostic tool for detecting and quantifying methylglyoxal in biological fluids. The developed method has been validated under FDA guidelines. A full scan-range was set from m/z 39 to 144/999 and the molecular weight of the 2-methylquinoxaline was identified according to NIST Database and ES. Methylglyoxal was the only analyte successfully quantified in a relatively short run time. It was linear over a concentration range of 0.057-5.7  µg.ml-1with mean recoveries and RSD of 118% and 3.63% respectively. The intra and inter-day assays were satisfying and not exceed 3.00%. Results reflect the degree of precision of our method and indicate that MGO was an important contributor to understand the hepatic failure independently of other serum markers.


Assuntos
Biomarcadores/sangue , Fasciolíase/diagnóstico , Fasciolíase/veterinária , Cromatografia Gasosa-Espectrometria de Massas/métodos , Aldeído Pirúvico/sangue , Animais , Bovinos , Cromatografia Líquida de Alta Pressão/métodos , Fasciola hepatica/isolamento & purificação , Feminino , Masculino
4.
Acta Parasitol ; 64(1): 112-128, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30689191

RESUMO

PURPOSE: The aim of our study is to establish the presence of Fasciola hepatica on farms in northeastern Algeria. METHODS: 143 blood and coprological samples of 15 males and 128 females of different breeds and ages were analysed. RESULTS: Our study indicates a heterogeneous level of the anti-f2 antibodies to Fasciola hepatica in response to the infection. The overall seroprevalence was about 22.37%, and 9 out of 13 investigated farms were infected, with rates varying from 5.88% to 70%. To explain the intrinsic variability of the infection, we identified age, sex and breed as potential risk factors. Based on this, we collected information about their relevance. There was a significant difference for age (p = 0.018) and coprology (p < 0.0001). Independently, sex and breed had no impact on the infection, although males were more infected (27%) than females (22%). Of the five investigated breeds, Holstein cattle (31.11%) were most affected, followed by Montbeliard (20.27%) and crossed breed (13.64%). Multivariate comparisons showed that the presence of faecal eggs reflects the active infectious status of cattle (p < 0.0001), while age (p = 0.011) and sex (p = 0.040) significantly impact the chance of acquiring the infection. To evaluate liver parenchyma integrity and its functionality, hepatic enzymes were examined and showed relatively low levels of aminotransferases, excluding cytolisis. Although sensitive to distomatosis, γGT and PAL values were inconsistent with the infection rate. The relatively high levels of proteins and albumin eliminate hepatic insufficiency. CONCLUSION: Our results suggest a chronic fasciolosis, confirmed by histology and SEM.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Fasciola hepatica/isolamento & purificação , Fasciolíase/veterinária , Argélia/epidemiologia , Animais , Anticorpos Anti-Helmínticos/sangue , Sangue/imunologia , Bovinos , Enzimas/análise , Fasciolíase/epidemiologia , Fasciolíase/parasitologia , Fezes/parasitologia , Fígado/patologia , Microscopia Eletrônica de Varredura , Contagem de Ovos de Parasitas , Fatores de Risco , Estudos Soroepidemiológicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA