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1.
Food Chem ; 304: 125448, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491713

RESUMO

Blood, from slaughterhouses, is an inevitable part of meat production, causing environmental problems due to the large volumes recovered and its low valorization. However, the α137-141 peptide, a natural antimicrobial peptide, can be obtained after hydrolysis of hemoglobin, the main constituent of blood red part. To recover it at a sufficient concentration for antimicrobial applications, a new sustainable technology, called electrodialysis with ultrafiltration membrane (EDUF), was investigated. The α137-141 concentration was increased about 4-fold at a feed peptide concentration of 8% with an enrichment factor above 24-fold. This feed peptide concentration also needed the lowest relative energy consumption. Moreover, this peptide fraction protected meat against microbial growth, as well as rancidity, during 14 days under refrigeration. This peptide fraction was validated as a natural preservative and substitute for synthetic additives against food spoilage. Finally, producing antimicrobial/antioxidant peptide from wastes by EDUF fits perfectly with the concept of circular economy.

2.
Pharmacol Ther ; 203: 107396, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31356908

RESUMO

Ursodeoxycholic acid (UDCA) is a secondary bile acid issued from the transformation of (cheno)deoxycholic acid by intestinal bacteria, acting as a key regulator of the intestinal barrier integrity and essential for lipid metabolism. UDCA is also a long-established drug, largely used for the dissolution of cholesterol gallstones, the treatment of primary biliary cholangitis and other hepatobiliary disorders. The history of UDCA is briefly retraced here as well as its multifactorial mechanism of action, based on its anti-inflammatory, antioxidant and cytoprotective activities. The present review is centred around the anticancer properties of UDCA and synthetic antitumor derivatives designed over the past 20 years. Paradoxically, depending on the conditions, UDCA exhibits both pro- and anti-apoptotic properties toward different cell types. In particular, the UDCA drug can protect epithelial cells from damages and apoptosis while inducing inhibition of proliferation and apoptotic and/or autophagic death of cancer cells. The effects of UDCA on cancer cell migration, cancer stem cells and drug-induced dysbiosis are also evoked. The drug has revealed modest activities against colon and gastric cancers but may be useful to improve treatments of hepatocellular carcinoma, notably in combination with other drugs such as sorafenib. UDCA can also protect from damages induced by cancer chemotherapeutic agents. The potential of UDCA in cancer, as a chemo-protecting or chemotherapeutic agent, is highlighted here as well as the design of tumour-active derivatives, including UDCA-drug conjugates. A repurposing of UDCA in oncology should be further considered.

3.
Exp Physiol ; 104(2): 254-263, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30561141

RESUMO

NEW FINDINGS: What is the central question of this study? Is there an association of plasma concentration of asymmetric dimethylarginine, which is related to exercise capacity in patients with cardiovascular diseases, with oxygen delivery and subsequently exercise capacity in healthy subjects in the absence of the potentially confounding influence of inflammation and oxidative stress? What is the main finding and its importance? Plasma asymmetric dimethylarginine concentrations are not related to exercise capacity in healthy subjects, while O2 delivery in the working skeletal muscle during the maximal graded-exercise test is not associated with any of the l-arginine analogues. ADMA alone does not play a crucial role in local muscle perfusion and in maintaining exercise capacity. ABSTRACT: Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) synthesis that could limit oxygen (O2 ) delivery in the working skeletal muscles by altering endothelium-dependent vasodilatation. Exercise capacity is associated with plasma ADMA concentrations in patients with cardiovascular diseases, but this issue has still not been investigated in healthy subjects. We aimed to determine whether plasma ADMA concentrations were negatively associated with exercise capacity in young healthy male subjects. Ten men with maximal oxygen uptake ( V ̇ O 2 max ) > 65 mL kg-1  min-1 were included in the high exercise capacity group (HI-FIT), and 10 men with V ̇ O 2 max  < 45 mL kg-1  min-1 were included in the low exercise capacity group (LO-FIT). Plasma ADMA and other l-arginine analogue concentrations were measured before and after a maximal graded-exercise test by liquid chromatography-tandem mass spectrometry. Microvascular O2 delivery during exercise was estimated through the pattern from the sigmoid model of muscle deoxygenation in the vastus lateralis measured by near infrared spectroscopy. V ̇ O 2 max was 60% higher in the HI-FIT group (median: 70.2 mL kg-1  min-1 ; IQR: 68.0-71.9 mL kg-1  min-1 ) than in the LO-FIT group (median: 43.8 mL kg-1  min-1 ; IQR: 34.8-45.3 mL kg-1  min-1 ). Plasma ADMA concentrations did not differ between the LO-FIT and HI-FIT groups before (0.50 ± 0.06 vs. 0.54 ± 0.07 µmol L-1 , respectively) and after the maximal incremental exercise test (0.49 ± 0.08 vs. 0.55 ± 0.03 µmol L-1 , respectively). There was no significant association of plasma ADMA concentrations with the pattern of local muscle deoxygenation and exercise capacity. Exercise capacity and microvascular O2 delivery are not related to plasma ADMA concentrations in young healthy male subjects. Our findings show that ADMA does not play a crucial role in local muscle perfusion and in maintaining exercise capacity without pathological conditions.


Assuntos
Arginina/análogos & derivados , Exercício/fisiologia , Oxigênio/metabolismo , Resistência Física/fisiologia , Adulto , Arginina/sangue , Arginina/metabolismo , Treino Aeróbico/métodos , Teste de Esforço , Humanos , Masculino , Músculos/metabolismo , Óxido Nítrico/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-29692758

RESUMO

A qualitative study is presented, where the main question was whether food-derived hemorphins, i.e., originating from digested alimentary hemoglobin, could pass the intestinal barrier and/or the blood-brain barrier (BBB). Once absorbed, hemorphins are opioid receptor (OR) ligands that may interact with peripheral and central OR and have effects on food intake and energy balance regulation. LLVV-YPWT (LLVV-H4), LVV-H4, VV-H4, VV-YPWTQRF (VV-H7), and VV-H7 hemorphins that were previously identified in the 120 min digest resulting from the simulated gastrointestinal digestion of hemoglobin have been synthesized to be tested in in vitro models of passage of IB and BBB. LC-MS/MS analyses yielded that all hemorphins, except the LLVV-H4 sequence, were able to cross intact the human intestinal epithelium model with Caco-2 cells within 5-60 min when applied at 5 mM. Moreover, all hemorphins crossed intact the human BBB model with brain-like endothelial cells (BLEC) within 30 min when applied at 100 µM. Fragments of these hemorphins were also detected, especially the YPWT common tetrapeptide that retains OR-binding capacity. A cAMP assay performed in Caco-2 cells indicates that tested hemorphins behave as OR agonists in these cells by reducing cAMP production. We further provide preliminary results regarding the effects of hemorphins on tight junction proteins, specifically here the claudin-4 that is involved in paracellular permeability. All hemorphins at 100 µM, except the LLVV-H4 peptide, significantly decreased claudin-4 mRNA levels in the Caco-2 intestinal model. This in vitro study is a first step toward demonstrating food-derived hemorphins bioavailability which is in line with the growing body of evidence supporting physiological functions for food-derived peptides.

5.
Gut ; 67(2): 271-283, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28377388

RESUMO

OBJECTIVE: To investigate the beneficial role of prebiotics on endothelial dysfunction, an early key marker of cardiovascular diseases, in an original mouse model linking steatosis and endothelial dysfunction. DESIGN: We examined the contribution of the gut microbiota to vascular dysfunction observed in apolipoprotein E knockout (Apoe-/-) mice fed an n-3 polyunsaturated fatty acid (PUFA)-depleted diet for 12 weeks with or without inulin-type fructans (ITFs) supplementation for the last 15 days. Mesenteric and carotid arteries were isolated to evaluate endothelium-dependent relaxation ex vivo. Caecal microbiota composition (Illumina Sequencing of the 16S rRNA gene) and key pathways/mediators involved in the control of vascular function, including bile acid (BA) profiling, gut and liver key gene expression, nitric oxide and gut hormones production were also assessed. RESULTS: ITF supplementation totally reverses endothelial dysfunction in mesenteric and carotid arteries of n-3 PUFA-depleted Apoe-/- mice via activation of the nitric oxide (NO) synthase/NO pathway. Gut microbiota changes induced by prebiotic treatment consist in increased NO-producing bacteria, replenishment of abundance in Akkermansia and decreased abundance in bacterial taxa involved in secondary BA synthesis. Changes in gut and liver gene expression also occur upon ITFs suggesting increased glucagon-like peptide 1 production and BA turnover as drivers of endothelium function preservation. CONCLUSIONS: We demonstrate for the first time that ITF improve endothelial dysfunction, implicating a short-term adaptation of both gut microbiota and key gut peptides. If confirmed in humans, prebiotics could be proposed as a novel approach in the prevention of metabolic disorders-related cardiovascular diseases.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Frutanos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Prebióticos , Aminopeptidases/genética , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Bactérias/efeitos dos fármacos , Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/sangue , Artérias Carótidas/fisiologia , Ceco/microbiologia , Suplementos Nutricionais , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/deficiência , Expressão Gênica/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/biossíntese , Masculino , Artérias Mesentéricas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Neurotensina/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Proglucagon/genética , Simportadores/genética , Vasodilatação
6.
J Anal Toxicol ; 41(8): 670-678, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28985322

RESUMO

Electronic cigarette use has raised concern worldwide regarding potential health risks and its position in tobacco cessation strategies. As part of any toxicity assessment, the chemical characterization of e-liquids and their related vapors are among fundamental data to be determined. Considering the lack of available reference methods, we developed and validated several analytical procedures in order to conduct a multicomponent analysis of six e-liquid refills and their resultant vapor emissions (generated by a smoking machine), and compared them with tobacco smoke. We combined several techniques including gas-chromatography, high and ultra-performance liquid chromatography and inductively coupled plasma with mass spectrometry or ultraviolet and flame ionization detection in order to identify the main e-liquid constituents (propylene glycol, glycerol and nicotine), as well as multiple potentially harmful components (trace elements, polycyclic aromatic hydrocarbons (PAHs), pesticides and carbonyl compounds). Regarding propylene glycol, glycerol and nicotine concentrations, the six tested e-liquids comply with the advertised composition and contain only traces of pollutants. Noticeable lower concentrations of trace elements (≤3.4 pg/mL puff), pesticides (

Assuntos
Aerossóis/análise , Sistemas Eletrônicos de Liberação de Nicotina , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Substâncias Perigosas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Propilenoglicol/análise
7.
Sci Total Environ ; 609: 982-991, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-28783915

RESUMO

The relevance of Polar Organic Chemical Integrative Samplers (POCIS) was evaluated for the assessment of concentrations of 46 pesticides and 19 pharmaceuticals in a small, peri-urban river with multi-origin inputs. Throughout the period of POCIS deployment, 24h-average water samples were collected automatically, and showed the rapid temporal evolution of concentrations of several micropollutants, as well as permitting the calculation of average concentrations in the water phase for comparison with those estimated from POCIS passive samplers. In the daily water samples, cyproconazol, epoxyconazol and imidacloprid showed high temporal variations with concentrations ranging from under the limit of detection up to several hundreds of ngL-1. Erythromycin, cyprofloxacin and iopromide also increased rapidly up to tens of ngL-1 within a few days. Conversely, atrazine, caffeine, diclofenac, and to a lesser extent carbamazepine and sucralose, were systematically present in the water samples and showed limited variation in concentrations. For most of the substances studied here, the passive samplers gave reliable average concentrations between the minimal and maximal daily concentrations during the time of deployment. For pesticides, a relatively good correlation was clearly established (R2=0.89) between the concentrations obtained by POCIS and those gained from average water samples. A slight underestimation of the concentration by POCIS can be attributed to inappropriate sampling rates extracted from the literature and for our system, and new values are proposed. Considering the all data set, 75% of the results indicate a relatively good agreement between the POCIS and the average water samples concentration (values of the ratio ranging between 0,33 and 3). Note further that this agreement between these concentrations remains valid considering different sampling rates extracted from the literature.

8.
J Pharm Biomed Anal ; 137: 113-122, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28110167

RESUMO

The aim of this study was to develop a method combining chiral separation and biophysical techniques to evaluate the enantioselective affinity of original sulfonamide derivatives towards their therapeutic target, the human carbonic anhydrase II (hACII). The first step consisted in the preparation of the enantiomers by chromatographic separation. The performances of HPLC and Supercritical Fluid Chromatography (SFC) were studied at the analytical scale by optimization of various experimental conditions using adsorbed polysaccharide chiral stationary phases (amylose AD-H and cellulose OD-H). Since SFC allowed obtaining higher enantioresolutions per time unit, it was selected for the semi-preparative scale and successfully used to isolate each enantiomer with a satisfactory enantiomeric purity (>98%). Secondly, microscale thermophoresis (MST) method and surface plasmon resonance (SPR) used as reference method were developed to measure potential enantioselective affinities of these enantiomers towards the hACII. The optimizations of both methods were performed using a reference compound, i.e. acetazolamide, which affinity for hCAII has previously been demonstrated. For all compounds, KD values obtained using MST and SPR were in good agreement, leading to similar affinity scales despite both approaches totally differ (labeling for MST versus immobilization of the protein for SPR). The equilibrium dissociation constants of our original compounds for the hCAII were in the range 100-1000nM and an enantioselectivity was observed using the MST and SPR methods for the diarylpyrazole 2. Finally, by comparing the MST and SPR techniques, MST appears especially adapted for further screening of a series of sulfonamide derivatives due to the lower time required to estimate a binding constant while consuming as little hCAII as SPR.


Assuntos
Anidrase Carbônica II/química , Sulfonamidas/química , Acetazolamida/química , Amilose/química , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Humanos , Polissacarídeos/química , Estereoisomerismo , Ressonância de Plasmônio de Superfície/métodos
9.
Mol Neurobiol ; 54(7): 5361-5374, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27590138

RESUMO

In amyotrophic lateral sclerosis (ALS), motor neuron degeneration is associated with systemic metabolic impairment. However, the evolution of metabolism alteration is partially unknown and its link with disease progression has never been described. For the first time, we ran a study focused on (1) the evolution of metabolism disturbance during disease progression through omics approaches and (2) the relation between metabolome profile and clinical evolution. SOD1-G93A (mSOD1) transgenic mice (n = 11) and wild-type (WT) littermates (n = 17) were studied during 20 weeks. Metabolomic profile of muscle and cerebral cortex was analysed at week 20, and plasma samples were assessed at four time points over 20 weeks. The relevant metabolic pathways highlighted by metabolomic analysis were explored by a targeted transcriptomic approach in mice. Plasma metabolomics were also performed in 24 ALS patients and 24 gender- and age-matched controls. Metabolomic analysis of muscle and cerebral cortex enabled an excellent discrimination between mSOD1 and WT mice (p < 0.001). These alterations included especially tryptophan, arginine, and proline metabolism pathways (including polyamines) as also revealed by transcriptomic analysis and findings in ALS patients. Multivariate models performed to explain clinical findings in ALS mice, and patients were excellent (p < 0.01) and highlighted three main metabolic pathways: arginine and proline, tryptophan, and branched amino acid metabolism. This work is the first longitudinal study that evaluates metabolism alteration in ALS, including the analysis of different tissues and using a combination of omics methods. We particularly identified arginine and proline metabolism. This pathway is also associated with disease progression and may open new perspectives of therapeutic targets.


Assuntos
Esclerose Amiotrófica Lateral/metabolismo , Arginina/metabolismo , Neurônios Motores/metabolismo , Prolina/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Humanos , Estudos Longitudinais , Masculino , Metabolômica/métodos , Camundongos Transgênicos , Superóxido Dismutase/genética , Triptofano/metabolismo
10.
Anal Biochem ; 511: 42-51, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27485269

RESUMO

This work was dedicated to the development of a reliable SPR method allowing the simultaneous and quick determination of the affinity and selectivity of designed sulfonamide derivatives for hCAIX and hCAXII versus hCAII, in order to provide an efficient tool to discover drugs for anticancer therapy of solid tumors. We performed for the first time a comparison of two immobilization approaches of hCA isoforms. First one relies on the use of an amine coupling strategy, using a CM7 chip to obtain higher immobilization levels than with a CM5 chip and consequently the affinity with an higher precision (CV% < 10%). The second corresponds to a capture of proteins on a streptavidin chip, named CAP chip, after optimization of biotinylation conditions (amine versus carboxyl coupling, biotin to protein ratio). Thanks to the amine coupling approach, only hCAII and hCAXII isoforms were efficiently biotinylated to reach relevant immobilization (3000 RU and 2700 RU, respectively) to perform affinity studies. For hCAIX, despite a successful biotinylation, capture on the CAP chip was a failure. Finally, concordance between affinities obtained for the three derivatives to CAs isozymes on both chips has allowed to valid the approaches for a further screening of new derivatives.


Assuntos
Biotina/química , Anidrases Carbônicas/química , Enzimas Imobilizadas/química , Sulfonamidas/química , Biotinilação , Humanos , Isoenzimas/química
11.
Neurotherapeutics ; 13(4): 905-917, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27444617

RESUMO

In amyotrophic lateral sclerosis (ALS), motor neuron degeneration occurs simultaneously with systemic metabolic impairment and neuroinflammation. Playing an important role in the regulation of both phenomena, interleukin (IL)-6, a major cytokine of the inflammatory response has been proposed as a target for management of ALS. Although a pilot clinical trial provided promising results in humans, another recent preclinical study showed that knocking out the IL-6 gene in mice carrying ALS did not improve clinical outcome. In this study, we aimed to determine the relevance of the IL-6 pathway blockade in a mouse model of ALS by using a pharmacological antagonist of IL-6, a murine surrogate of tocilizumab, namely MR16-1. We analyzed the immunological and metabolic effects of IL-6 blockade by cytokine measurement, blood cell immunophenotyping, targeted metabolomics, and transcriptomics. A deleterious clinical effect of MR16-1 was revealed, with a speeding up of weight loss (p = 0.0041) and decreasing body weight (p < 0.05). A significant increase in regulatory T-cell count (p = 0.0268) and a decrease in C-X-C ligand-1 concentrations in plasma (p = 0.0479) were observed. Metabolomic and transcriptomic analyses revealed that MR16-1 mainly affected branched-chain amino acid, lipid, arginine, and proline metabolism. IL-6 blockade negatively affected body weight, despite a moderated anti-inflammatory effect. Metabolic effects of IL-6 were mild compared with metabolic disturbances observed in ALS, but a modification of lipid metabolism by therapy was identified. These results indicate that IL-6 blockade did not improve clinical outcome of a mutant superoxide dismutase 1 mouse model of ALS.


Assuntos
Esclerose Amiotrófica Lateral/tratamento farmacológico , Esclerose Amiotrófica Lateral/metabolismo , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Interleucina-6/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Esclerose Amiotrófica Lateral/genética , Animais , Peso Corporal/genética , Citocinas/sangue , Avaliação da Deficiência , Modelos Animais de Doenças , Seguimentos , Redes Reguladoras de Genes , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Interleucina-6/genética , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos
12.
J Chromatogr A ; 1455: 163-171, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27286645

RESUMO

The performances of three neutral static coatings (hydroxypropyl cellulose, polyethylene oxide and poly(N,N-dimethylacrylamide) have been evaluated in order to determine the binding constants of the complexes formed between four polycationic compounds (piperazine derivatives) and four cyclodextrins of pharmaceutical interest (ß-CD, HP-ß-CD, Me-ß-CD and sulfobutyl ether-ß-CD) by affinity capillary electrophoresis. The physically-adsorbed poly(N,N-dimethylacrylamide) coating proves to be the more efficient to mask the silanol groups of the capillary wall since the lowest electroosmotic flow was measured for this coating. Moreover, it drastically reduces the adsorption of the compounds since it allows a correct repeatability of their migration time, higher efficiencies of the peaks and no baseline shift. Then, it was verified for four complexes that this coating allows a correct determination of the binding constants avoiding the CD adsorption which is responsible of an undervaluation of binding constants. The highest binding constants are obtained using the anionic sulfobutyl ether-ß-CD (SBE-ß-CD). The structure of the complex formed between the tacrine derivative and the SBE-ß-CD was further investigated through 2D ROESY NMR experiments and structure-binding constant relationships. Results suggest that the inclusion in the SBE-ß-CD cavity occurs through the aliphatic ring portion of the tacrine moiety.


Assuntos
Ciclodextrinas/química , Eletroforese Capilar , Piperazinas/química , Acrilamidas/química , Celulose/análogos & derivados , Celulose/química , Espectroscopia de Ressonância Magnética , Piperazinas/isolamento & purificação , Polietilenoglicóis/química , Viscosidade
13.
Electrophoresis ; 37(13): 1814-22, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26990205

RESUMO

Consumers and governments have become aware how the daily diet may affect the human health. All proteins from both plant and animal origins are potential sources of a wide range of bioactive peptides and the large majority of those display health-promoting effects. In the meat production food chain, the slaughterhouse blood is an inevitable co-product and, today, the blood proteins remain underexploited despite their bioactive potentiality. Through a comparative food peptidomics approach we illustrate the impact of resolving power, accuracy, sensitivity, and acquisition speed of low-resolution (LR)- and high-resolution (HR)-LC-ESI-MS/MS on the obtained peptide mappings and discuss the limitations of MS-based peptidomics. From in vitro gastrointestinal digestions of partially purified bovine hemoglobin, we have established the peptide maps of each hemoglobin chain. LR technique (normal bore C18 LC-LR-ESI-MS/MS) allows us to identify without ambiguity 75 unique peptides while the HR approach (nano bore C18 LC-HR-ESI-MS/MS) unambiguously identify more than 950 unique peptides (post-translational modifications included). Herein, the food peptidomics approach using the most performant separation methods and mass spectrometers with high-resolution capabilities appears as a promising source of information to assess the health potentiality of proteins.


Assuntos
Cromatografia Líquida/métodos , Digestão , Análise de Alimentos , Hemoglobinas/metabolismo , Peptídeos/metabolismo , Proteômica , Espectrometria de Massas em Tandem/métodos , Animais , Bovinos , Técnicas In Vitro , Mapeamento de Peptídeos
14.
Bioorg Med Chem ; 24(4): 651-60, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26740155

RESUMO

Three series of indeno[1,2-c]isoquinolines bearing a ferrocenyl entity were synthesized and evaluated for DNA interaction, topoisomerase I and II inhibition, and cytotoxicity against breast human cancer cell lines. In the first and second series, the ferrocenyl scaffold was inserted as a linker between the two nitrogen atoms. In the last series, it was introduced at the end of the carbon chain. The present study showed that the ferrocenyl entity enhanced the topoisomerase II inhibition. Most compounds showed a potent growth inhibitory effect on MDA-MB-231 cell line with the IC50 in µM range.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ligação a DNA/antagonistas & inibidores , Compostos Ferrosos/síntese química , Compostos Ferrosos/farmacologia , Isoquinolinas/síntese química , Isoquinolinas/farmacologia , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/farmacologia , Antígenos de Neoplasias/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Compostos Ferrosos/química , Humanos , Concentração Inibidora 50 , Isoquinolinas/química , Estrutura Molecular , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/química , Células Tumorais Cultivadas
15.
Food Res Int ; 89(Pt 1): 382-390, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28460928

RESUMO

Dietary proteins have been reported to induce a strong feeling of satiety that has been partially explained by gut hormone level increase. Up to date, various protein hydrolysates have demonstrated in vitro and in vivo their potential to stimulate gut hormone secretion related to food intake decrease and their mechanisms of action have just started to be resolved. In this context, this study aimed at identifying new peptide sequences involved in gut hormone secretion released by protein in vitro gastrointestinal digestion. Targeted gut hormones were Cholecystokinin (CCK) and Glucagon-Like Peptide 1 (GLP-1). The activity of DPP-IV was also considered as it strongly modulates GLP-1 action. In a previous study, simulated digestion of dietary protein has generated hydrolysates with enhancing effect on CCK and GLP-1 secretion in STC-1 cells as well as DPP-IV inhibitory properties. Successive purification steps were performed to isolate peptide fractions involved in these bioactivities whose sequence was determined by LC-MS-MS. Three peptide sequences ANVST, TKAVEH and KAAVT were pointed out for their stimulating effects on GLP-1 secretion. The sequence VAAA was isolated for its DPP-IV inhibitory properties. Two peptide groups were strongly involved in CCK release sharing a certain occurrence of aromatic amino acid residues.

16.
Carbohydr Polym ; 115: 598-604, 2015 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-25439937

RESUMO

The complexes formed between six original chiral diaryl-pyrazole sulfonamide derivatives, displaying poor solubility, and various CDs (native α-, ß- and γ-CDs, hydroxypropylated HP-ß-CD, methylated Me-ß-CD or amino NH2-ß-CD) were studied by 1D and 2D (1)H NMR at physiological pH in order to determine their apparent binding constant, stoichiometry and structure of the supramolecular assembly. For some complexes, the spectra obtained for free racemic compound and for racemic compound in presence of CD indicate a splitting of signal(s). Additional experiments with pure enantiomer and enriched enantiomer allow us to attribute this behavior to chiral discrimination. The complexing ability of the native ß-CD towards our compounds appears the most promising since binding values around 7×10(2)M(-1) are obtained. The two-dimensional ROESY ((1)H-(1)H) experiments prove the inclusion of the aliphatic part of the compound in the CD cavity. It is noteworthy that this inclusion occurs via the smaller opening of the cavity.


Assuntos
Ciclodextrinas/química , Pirazóis/química , Sulfonamidas/química , Espectroscopia de Ressonância Magnética
17.
ScientificWorldJournal ; 2014: 583180, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25548785

RESUMO

A method for the simultaneous determination of free chlorogenic acids (CGA) and sesquiterpene lactones (STL) in chicory root and its dried (flour) and roasted (grain) forms is described. The method uses one extraction and one analysis for all chicory root products. Various solvents with low to high polarity, such as methanol, chloroform, or n-hexane, were tested alone, in combination in different proportions or with acidified or neutral aqueous solvent. The water/chloroform/methanol (30/30/40, v/v/v) mixture generated the best extraction yield, 21% higher than alcohol mixtures. The profiling of CGA and STL content was performed through a conventional HPLC-DAD method using a PFP core shell column in a fast single run. Good retention time and area repeatability (RDD mean % 0.46 and 5.6, resp.) and linearity (R2≥0.96) were obtained. The STL and chlorogenic acids levels determined were 254.7 and 100.2 µg/g of dry matter in the root, 792.5 and 1,547 µg/g in flour, and 160.4 and 822.5 µg/g in the roasted grains, respectively. With an average recovery of 106% and precision of 90%, this method is rapid, reproducible, and straightforward way to quantify the chlorogenic acids and STL in chicory raw material and end products.


Assuntos
Chicória/química , Ácido Clorogênico/análise , Análise de Alimentos/métodos , Lactonas/análise , Raízes de Plantas/química , Sesquiterpenos/análise , Ácido Clorogênico/química , Cromatografia Líquida de Alta Pressão , Farinha/análise , Lactonas/química , Limite de Detecção , Reprodutibilidade dos Testes , Sesquiterpenos/química , Fatores de Tempo
18.
Pharmacology ; 94(3-4): 170-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25342590

RESUMO

BACKGROUND/AIMS: The in vivo metabolic profile of a benzopyridooxathiazepine (BPT) derivative, a potent tubulin polymerization inhibitor with a promising in vitro activity, was investigated. METHODS: The quantification of the BPT derivative and the identification of metabolites in the plasma of Wistar rats after i.p. and oral administration of 10 mg/kg were performed by the HPLC-mass spectrometry method. RESULTS: Following a single i.p. dose of the BPT derivative, the plasma concentrations showed a biexponential decay (with a rapid decline) followed by a slow decay with a terminal half-life of 77.90 min. The area under the concentration-time curve from time 0 to infinity (AUC0-∞) was 18.90 µg/ml·min. After oral administration, the plasmatic concentrations reached a peak of 0.06 µg/ml at 35 min and then decayed with a half-life of 108 min. The AUC0-∞ was 10.25 µg/ml·min, representing 54.2% of the relative bioavailability. The compound was well distributed in the body, and its elimination seemed to be fast, regardless of the administration route. The major metabolic pathways were demethylation and hydroxylation reactions, both followed by conjugation with glucuronic acid. CONCLUSION: In rats, the BPT derivative is well distributed and undergoes extensive metabolism, leading to several metabolites. With promising in vitro activity and very good oral bioavailability, this compound seems to be an attractive candidate for further development as an anticancer agent.


Assuntos
Antineoplásicos/farmacocinética , Tiazepinas/farmacocinética , Animais , Antineoplásicos/sangue , Antineoplásicos/toxicidade , Disponibilidade Biológica , Feminino , Ratos Wistar , Tiazepinas/sangue , Tiazepinas/toxicidade
19.
Electrophoresis ; 35(19): 2765-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24723380

RESUMO

A CE method using dual cationic and neutral cyclodextrins (CD) was optimized for the enantiomeric separation of a compound presenting a diaryl sulfonamide group. Preliminary studies were made to select the optimal CDs and pH of the BGE. Two CDs (amino-ß-CD and ß-CD) were selected to separate the enantiomers in a 67 mM phosphate buffer at pH 7.4. However, the repeatability of the analyses obtained on bare-fused silica capillary was not acceptable owing to the adsorption of the amino-ß-CD to the capillary. To prevent this, a dynamic coating of the capillary was used employing five layers of ionic-polymer (poly(diallyldimethylammonium) chloride (PDADMAC) and poly(sodium 4-styrenesulfonate). The efficiency of the coating was assessed by measuring the EOF stability. Repeatability of the injections was obtained when intermediate coating with PDADMAC was performed between each run. Secondly, this enantioseparation method was optimized using a central composite circumscribed design including three factors: amino-ß-CD and ß-CD concentrations and the percentage of methanol. Under the optimal conditions (i.e. 16.6 mM of amino-ß-CD, 2.6 mM of ß-CD, 0% MeOH in 67 mM phosphate buffer (pH 7.4) as BGE, cathodic injection 0.5 psi, 5 s, separation voltage 15 kV and a temperature of 15°C), complete enantioresolution of the analyte was obtained. It is worth mentioning that the design of experiments (DOE) protocol employed showed a significant interaction between CDs, highlighting the utility of DOE in method development. Finally, small variations in the ionic-polymer concentrations did not significantly influence the EOF, confirming the robustness of the coating method.


Assuntos
Eletroforese Capilar/instrumentação , Eletroforese Capilar/métodos , Sulfonamidas/química , Sulfonamidas/isolamento & purificação , beta-Ciclodextrinas/química , Polímeros , Reprodutibilidade dos Testes , Projetos de Pesquisa , Estereoisomerismo
20.
J Mol Recognit ; 27(1): 46-56, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24375583

RESUMO

This work describes the development of biophysical unbiased methods to study the interactions between new designed compounds and carbonic anhydrase II (CAII) enzyme. These methods have to permit both a screening of a series of sulfonamide derivatives and the identification of a lead compound after a thorough study of the most promising molecules. Interactions data were collected using surface plasmon resonance (SPR) and thermal shift assay (TSA). In the first step, experiments were performed with bovine CAII isoform and were extended to human CAII. Isothermal titration calorimetry (ITC) experiments were also conducted to obtain thermodynamics parameters necessary for the processing of the TSA data. Results obtained with this reference methodology demonstrate the effectiveness of SPR and TSA. KD values obtained from SPR data were in perfect accordance with ITC. For TSA, despite the fact that the absolute values of KD were quite different, the same affinity scale was obtained for all compounds. The binding affinities of the analytes studied vary by more than 50 orders of magnitude; for example, the KD value determined by SPR were 6 ± 4 and 299 ± 25 nM for compounds 1 and 3, respectively. This paper discusses some of the theoretical and experimental aspects of the affinity-based methods and evaluates the protein consumption to develop methods for the screening of further new compounds. The double interest of SPR, that is, for screening and for the quick thorough study of the interactions parameters (ka , kd , and KD ), leads us to choose this methodology for the study of new potential inhibitors.


Assuntos
Calorimetria , Anidrase Carbônica II/metabolismo , Inibidores da Anidrase Carbônica/farmacologia , Fluorescência , Ressonância de Plasmônio de Superfície , Termodinâmica , Animais , Bovinos , Humanos , Cinética , Ligação Proteica
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