Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Magn Reson Chem ; 62(5): 328-336, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37736944

RESUMO

Omega-3 fatty acid supplements, such as fish oil and plant-based oils, have gained popularity because of their potential health benefits. However, the quality and composition of these supplements can vary widely, particularly in terms of the two main forms of omega-3 fatty acids: triacylglycerols (TAGs) and ethyl esters (EEs). TAGs are the natural form found in fish oil but are prone to oxidation, whereas EEs are more stable but less well absorbed by the body. Differentiating between these forms is crucial for assessing the efficacy and tolerance of omega-3 supplements. This article describes a novel approach to differentiate between TAG and EE forms of omega-3 fatty acids in dietary supplements, utilizing a 60-MHz benchtop nuclear magnetic resonance (NMR) spectrometer. The proposed method using 1H and 1H-1H COSY NMR provides a quick and accurate approach to screen the forms of omega-3 fatty acids and evaluate their ratios. The presence of diacylglycerol (DAGs) in some supplements was also highlighted by this method and adds some information about the process used (i.e., esterification/enrichment). The affordability and user-friendliness of benchtop NMR equipment make this method feasible for food processing companies or quality control laboratories. In this study, 24 oil supplements were analyzed using NMR analysis in order to demonstrate the potential of this method for the differentiation of TAG and EE forms in omega-3 supplements.


Assuntos
Ácidos Graxos Ômega-3 , Ácidos Graxos , Ácidos Graxos Ômega-3/química , Óleos de Peixe/química , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética
2.
Molecules ; 29(9)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38731577

RESUMO

Recently, benchtop nuclear magnetic resonance (NMR) spectrometers utilizing permanent magnets have emerged as versatile tools with applications across various fields, including food and pharmaceuticals. Their efficacy is further enhanced when coupled with chemometric methods. This study presents an innovative approach to leveraging a compact benchtop NMR spectrometer coupled with chemometrics for screening honey-based food supplements adulterated with active pharmaceutical ingredients. Initially, fifty samples seized by French customs were analyzed using a 60 MHz benchtop spectrometer. The investigation unveiled the presence of tadalafil in 37 samples, sildenafil in 5 samples, and a combination of flibanserin with tadalafil in 1 sample. After conducting comprehensive qualitative and quantitative characterization of the samples, we propose a chemometric workflow to provide an efficient screening of honey samples using the NMR dataset. This pipeline, utilizing partial least squares discriminant analysis (PLS-DA) models, enables the classification of samples as either adulterated or non-adulterated, as well as the identification of the presence of tadalafil or sildenafil. Additionally, PLS regression models are employed to predict the quantitative content of these adulterants. Through blind analysis, this workflow allows for the detection and quantification of adulterants in these honey supplements.


Assuntos
Suplementos Nutricionais , Mel , Espectroscopia de Ressonância Magnética , Mel/análise , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética/métodos , Citrato de Sildenafila/análise , Fluxo de Trabalho , Quimiometria/métodos , Tadalafila/análise , Análise dos Mínimos Quadrados , Contaminação de Medicamentos/prevenção & controle , Análise Discriminante
3.
Electrophoresis ; 44(3-4): 431-441, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36398472

RESUMO

Ammonium perfluorooctanoate (APFOA) was used as a surfactant for the separation of free unsaturated C18 fatty acids by micellar electrokinetic chromatography. A simple background electrolyte of 50 mM APFOA water/methanol (90:10, v/v) at pH = 10 enabled the repeatable separation of oleic acid, elaidic acid, linoleic acid, and alpha-linolenic acid in less than 20 min. Separation conditions were optimized regarding various parameters (organic solvent, counterion, APFOA concentration, and pH). Because the repulsive interactions between fluorocarbon chains and hydrogenated chains are known to lead to segregation and phase separation, the choice of perfluorinated micelles to separate such perhydrogenated long-chain acids could appear astonishing. Therefore, the critical micelle concentration, the charge density, and the mobility of the micelles have been determined, resulting in a first description of the separation process.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Micelas , Cromatografia Capilar Eletrocinética Micelar/métodos , Tensoativos/química , Caprilatos
4.
Macromol Rapid Commun ; 44(4): e2200729, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36443826

RESUMO

Photo-iniferter reversible addition-fragmentation chain transfer (PI-RAFT) polymerization of N-vinylformamide (NVF) is demonstrated by using purple light. PNVFs with predetermined molar masses and narrow molar mass distributions are obtained. High RAFT chain-end fidelity is confirmed by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) and electrospray-ionization time-of-flight mass spectrometry (ESI-TOF-MS), and chain extension experiment. To demonstrate the potential of this approach, an original poly(N-vinylpyrrolidone)-b-poly(N-vinylformamide) (PVP-b-PNVF) diblock copolymer is synthesized and characterized by aqueous size-exclusion chromatography (SEC), asymmetric flow field-flow fractionation (A4F), and 1 H diffusion-ordered spectroscopy nuclear magnetic resonance (1 H DOSY NMR). Finally, selective hydrolysis of PNVF block to corresponding pH-responsive poly(N-vinylpyrrolidone)-b-poly(N-vinylformamide) (PVP-b-PVAm) is performed.


Assuntos
Polivinil , Polimerização , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
5.
FASEB J ; 35(11): e21931, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34653285

RESUMO

Energetic metabolism controls key steps of kidney development, homeostasis, and epithelial repair following acute kidney injury (AKI). Hepatocyte nuclear factor-1ß (HNF-1ß) is a master transcription factor that controls mitochondrial function in proximal tubule (PT) cells. Patients with HNF1B pathogenic variant display a wide range of kidney developmental abnormalities and progressive kidney fibrosis. Characterizing the metabolic changes in PT cells with HNF-1ß deficiency may help to identify new targetable molecular hubs involved in HNF1B-related kidney phenotypes and AKI. Here, we combined 1 H-NMR-based metabolomic analysis in a murine PT cell line with CrispR/Cas9-induced Hnf1b invalidation (Hnf1b-/- ), clustering analysis, targeted metabolic assays, and datamining of published RNA-seq and ChIP-seq dataset to identify the role of HNF-1ß in metabolism. Hnf1b-/- cells grown in normoxic conditions display intracellular ATP depletion, increased cytosolic lactate concentration, increased lipid droplet content, failure to use pyruvate for energetic purposes, increased levels of tricarboxylic acid (TCA) cycle intermediates and oxidized glutathione, and a reduction of TCA cycle byproducts, all features consistent with mitochondrial dysfunction and an irreversible switch toward glycolysis. Unsupervised clustering analysis showed that Hnf1b-/- cells mimic a hypoxic signature and that they cannot furthermore increase glycolysis-dependent energetic supply during hypoxic challenge. Metabolome analysis also showed alteration of phospholipid biosynthesis in Hnf1b-/- cells leading to the identification of Chka, the gene coding for choline kinase α, as a new putative target of HNF-1ß. HNF-1ß shapes the energetic metabolism of PT cells and HNF1B deficiency in patients could lead to a hypoxia-like metabolic state precluding further adaptation to ATP depletion following AKI.


Assuntos
Células Epiteliais/metabolismo , Deleção de Genes , Glicólise/genética , Fator 1-beta Nuclear de Hepatócito/metabolismo , Homeostase/genética , Túbulos Renais Proximais/citologia , Transdução de Sinais/genética , Injúria Renal Aguda/metabolismo , Animais , Sistemas CRISPR-Cas , Hipóxia Celular/genética , Linhagem Celular , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação da Expressão Gênica , Técnicas de Inativação de Genes/métodos , Fator 1-beta Nuclear de Hepatócito/genética , Humanos , Metaboloma , Camundongos , Transcriptoma
6.
Molecules ; 25(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155779

RESUMO

The recent introduction of compact or low-field (LF) NMR spectrometers that use permanent magnets, giving rise to proton (1H) NMR frequencies between 40 and 80 MHz, have opened up new areas of application. The two main limitations of the technique are its insensitivity and poor spectral resolution. However, this study demonstrates that the chemometric treatment of LF 1H NMR spectral data is suitable for unveiling medicines as adulterants of slimming dietary supplements (DS). To this aim, 66 DS were analyzed with LF 1H NMR after quick and easy sample preparation. A first PLS-DA model built with the LF 1H NMR spectra from forty DS belonging to two classes of weight-loss DS (non-adulterated, and sibutramine or phenolphthalein-adulterated) led to the classification of 13 newly purchased test samples as natural, adulterated or borderline. This classification was further refined when the model was made from the same 40 DS now considered as representing three classes of DS (non-adulterated, sibutramine-adulterated, and phenolphthalein-adulterated). The adulterant (sibutramine or phenolphthalein) was correctly predicted as confirmed by the examination of the 1H NMR spectra. A limitation of the chemometric approach is discussed with the example of two atypical weight-loss DS containing fluoxetine or raspberry ketone.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Espectroscopia de Prótons por Ressonância Magnética , Suplementos Nutricionais/normas , Espectroscopia de Prótons por Ressonância Magnética/métodos
7.
Molecules ; 25(2)2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31941089

RESUMO

Red yeast rice dietary supplements (RYR DS) are largely sold in Western countries for their cholesterol-lowering/regulating effect due to monacolins, mainly monacolin K (MK), which is, in fact, lovastatin, the first statin drug on the market. 1H-NMR was used as an easy, rapid and accurate method to establish the chemical profiles of 31 RYR DS and to quantify their monacolin contents. Among all the 1H resonances of the monacolins found in RYR, only those of the ethylenic protons of the hexahydronaphthalenic ring at 5.84 and 5.56 ppm are suitable for quantification because they show no overlap with the matrix signals. The total content in monacolins per capsule or tablet determined in 28 DS (the content in 3 DS being below the limit of quantification of the method, ≈ 0.25 mg per unit dose) was close to that measured by UHPLC, as shown by the good linear correlation between the two sets of values (slope 1.00, y-intercept 0.113, r2 0.986). Thirteen of the 31 RYR DS analyzed (i.e., 42%) did not provide label information on the concentration of monacolins and only nine of the 18 formulations with an indication (i.e., 50%) actually contained the declared amount of monacolins.


Assuntos
Produtos Biológicos/análise , Suplementos Nutricionais/análise , Naftalenos/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular
8.
Molecules ; 24(6)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30889921

RESUMO

Origin and quality identification in dairy products is an important issue and also an extremely challenging and complex experimental procedure. The objective of the present work was to compare the metabolite profile of the lipid fraction of organic and conventional bovine milk using NMR metabolomics analysis. ¹H-NMR and 1D TOCSY NMR methods of analysis were performed on extracted lipid fraction of lyophilized milk. For this purpose, 14 organic and 16 conventional retail milk samples were collected monthly, and 64 bulk-tank (58 conventional and 6 organics) milk samples were collected over a 14-month longitudinal study in Cyprus. Data were treated with multivariate methods (PCA, PLS-DA). Minor components were identified and quantified, and modification of the currently used equations is proposed. A significantly increased % content of conjugated (9-cis, 11-trans)18:2 linoleic acid (CLA), α-linolenic acid, linoleic acid, allylic protons and total unsaturated fatty acids (UFA) and decreased % content for caproleic acid were observed in the organic samples compared to the conventional ones. The present work confirms that lipid profile is affected by contrasting management system (organic vs. conventional), and supports the potential of NMR-based metabolomics for the rapid analysis and authentication of the milk from its lipid profile.


Assuntos
Alimentos Orgânicos/análise , Lipídeos/química , Espectroscopia de Ressonância Magnética , Metabolômica/métodos , Leite/metabolismo , Animais , Bovinos , Análise Discriminante , Análise dos Mínimos Quadrados , Metaboloma , Leite/química , Valor Nutritivo , Análise de Componente Principal
9.
J Neurochem ; 140(6): 919-940, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28072448

RESUMO

Tissue non-specific alkaline phosphatase (TNAP) is a key player of bone mineralization and TNAP gene (ALPL) mutations in human are responsible for hypophosphatasia (HPP), a rare heritable disease affecting the mineralization of bones and teeth. Moreover, TNAP is also expressed by brain cells and the severe forms of HPP are associated with neurological disorders, including epilepsy and brain morphological anomalies. However, TNAP's role in the nervous system remains poorly understood. To investigate its neuronal functions, we aimed to identify without any a priori the metabolites regulated by TNAP in the nervous tissue. For this purpose we used 1 H- and 31 P NMR to analyze the brain metabolome of Alpl (Akp2) mice null for TNAP function, a well-described model of infantile HPP. Among 39 metabolites identified in brain extracts of 1-week-old animals, eight displayed significantly different concentration in Akp2-/- compared to Akp2+/+ and Akp2+/- mice: cystathionine, adenosine, GABA, methionine, histidine, 3-methylhistidine, N-acetylaspartate (NAA), and N-acetyl-aspartyl-glutamate, with cystathionine and adenosine levels displaying the strongest alteration. These metabolites identify several biochemical processes that directly or indirectly involve TNAP function, in particular through the regulation of ecto-nucleotide levels and of pyridoxal phosphate-dependent enzymes. Some of these metabolites are involved in neurotransmission (GABA, adenosine), in myelin synthesis (NAA, NAAG), and in the methionine cycle and transsulfuration pathway (cystathionine, methionine). Their disturbances may contribute to the neurodevelopmental and neurological phenotype of HPP.


Assuntos
Fosfatase Alcalina/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Hipofosfatasia/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Fosfatase Alcalina/deficiência , Animais , Feminino , Hipofosfatasia/genética , Masculino , Camundongos , Camundongos Knockout
10.
J Phys Chem A ; 119(24): 6215-22, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-25919339

RESUMO

We have investigated the removal of bortezomib, an anticancer drug prescribed in multiple myeloma, using the photochemical advanced oxidation process of V-UV/UV (185/254 nm). We used two complementary analytical techniques to follow the removal rate of bortezomib. Nuclear magnetic resonance (NMR) is a nonselective method requiring no prior knowledge of the structures of the byproducts and permits us to provide a spectral signature (fingerprinting approach). This untargeted method provides clues to the molecular structure changes and information on the degradation of the parent drug during the irradiation process. This holistic NMR approach could provide information for monitoring aromaticity evolution. We use liquid chromatography, coupled with high-resolution mass spectrometry (LC-MS), to correlate results obtained by (1)H NMR and for accurate identification of the byproducts, in order to understand the mechanistic degradation pathways of bortezomib. The results show that primary byproducts come from photoassisted deboronation of bortezomib at 254 nm. A secondary byproduct of pyrazinecarboxamide was also identified. We obtained a reliable correlation between these two analytical techniques.


Assuntos
Bortezomib/química , Espectroscopia de Ressonância Magnética/métodos , Processos Fotoquímicos , Antineoplásicos/química , Bortezomib/efeitos da radiação , Cromatografia Líquida , Espectrometria de Massas por Ionização por Electrospray , Raios Ultravioleta , Poluentes Químicos da Água/química
11.
BMC Complement Altern Med ; 14: 99, 2014 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-24621275

RESUMO

BACKGROUND: Salvia africana-lutea L., an important medicinal sage used in the Western Cape (South Africa), can be termed a 'broad-spectrum remedy' suggesting the presence of a multiplicity of bioactive metabolites. This study aimed at assessing wild S. africana-lutea populations for chemotypic variation and anti-Fusarium properties. METHODS: Samples were collected from four wild growing population sites (Yzerfontein, Silwerstroomstrand, Koeberg and Brackenfell) and one garden growing location in Stellenbosch. Their antifungal activities against Fusarium verticillioides (strains: MRC 826 and MRC 8267) and F. proliferatum (strains: MRC 6908 and MRC 7140) that are aggressive mycotoxigenic phytopathogens were compared using an in vitro microdilution assay. To correlate antifungal activity to chemical profiles, three techniques viz. Gas chromatography-mass spectrometry (GC-MS); Liquid chromatography-mass spectrometry (LC-MS) and 1H Nuclear Magnetic Resonance (NMR) were employed. Principal Component Analysis (PCA) was applied to the NMR data. The partial least squares-discriminant analysis (PLS-DA) was used to integrate LC-MS and NMR data sets. All statistics were performed with the SIMCA-P+12.0 software. RESULTS: The dichloromethane:methanol (1:1; v/v) extracts of the plant species collected from Stellenbosch demonstrated the strongest inhibition of F. verticillioides and F. proliferatum with minimum inhibitory concentration (MIC) values of 0.031 mg ml(-1) and 0.063 mg ml(-1) respectively. GC-MS showed four compounds which were unique to the Stellenbosch extracts. By integrating LC-MS and 1H NMR analyses, large chemotype differences leading to samples grouping by site when a multivariate analysis was performed, suggested strong plant-environment interactions as factors influencing metabolite composition. Signals distinguishing the Stellenbosch profile were in the aromatic part of the 1H NMR spectra. CONCLUSIONS: This study shows the potential of chemotypes of Salvia africana-lutea in controlling fungal growth and consequently mycotoxin production. Products for use in the agricultural sector may be developed from such chemotypes.


Assuntos
Antifúngicos/farmacologia , Fusarium/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Salvia/química , Salvia/metabolismo , Antifúngicos/química , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Metabolômica , Extratos Vegetais/química
12.
Biophys J ; 105(3): 667-78, 2013 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-23931315

RESUMO

In addition to their well-known DNA-binding properties, homeodomains have the ability to efficiently translocate across biological membranes through still poorly-characterized mechanisms. To date, most biophysical studies addressing the mechanisms of internalization have focused on small synthetic peptides rather than full-length globular homeodomains. In this work, we characterized the conformational properties of chicken Engrailed 2 homeodomain (En2HD) in aqueous solution and in membrane mimetic environments using circular dichroism, Trp fluorescence, and NMR spectroscopy. En2HD adopts a well-defined three-helical bundle fold in aqueous solution. The Trp-48 residue, which is critical for internalization, is fully buried in the hydrophobic core. Circular dichroism and fluorescence reveal that a conformational transition occurs in anionic lipid vesicles and in micelles. En2HD loses its native three-dimensional structure in micellar environments but, remarkably, near-native helical secondary structures are maintained. Long-range interactions could be detected using site-directed spin labels, indicating that the three helices do not adopt extended orientations. Noncovalent paramagnetic probes yielded information about helix positioning and unveiled the burial of critical aromatic and basic residues within the micelles. Our results suggest that electrostatic interactions with membranes may be determinant in inducing a conformational change enabling Trp-48 to insert into membranes.


Assuntos
Membrana Celular/metabolismo , Proteínas de Homeodomínio/química , Micelas , Proteínas do Tecido Nervoso/química , Sequência de Aminoácidos , Animais , Membrana Celular/química , Galinhas , Drosophila/química , Proteínas de Homeodomínio/metabolismo , Humanos , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/metabolismo , Estrutura Terciária de Proteína , Transporte Proteico
13.
J Pharm Biomed Anal ; 227: 115283, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36780864

RESUMO

Ten POWER dietary supplements, chronologically called tabs, pills then caps, and advertised as 100% natural aphrodisiacs, were analyzed by 1H NMR from 2007 to 2022. They were all tainted by PDE-5 inhibitors. Eight different adulterants were identified (sildenafil (1), sildenafil analogues (6), and vardenafil analogue (1)). Their amounts ranged from 15 to 145 mg/capsule. Four supplements contained at least 100 mg/capsule of PDE-5 inhibitor or analogue, the maximal recommended dose of sildenafil. The nature of the adulterant has changed over time, probably to evade its detection by regulatory agencies routine screening tests. Despite several warnings and/or seizures from several European food and/or health authorities, the dietary supplement POWER is still on sale on the Internet, thus demonstrating the impossibility of controlling this market. Faced with this situation, the consumer should be better informed by establishing at the European level a public database of tainted dietary supplements on the model of that of the US Food and Drug Administration. It should indicate the product name, its photo, the adulterant name, and be easily accessible to everyone.


Assuntos
Suplementos Nutricionais , Inibidores da Fosfodiesterase 5 , Suplementos Nutricionais/análise , Contaminação de Medicamentos/prevenção & controle , Espectroscopia de Ressonância Magnética , Inibidores da Fosfodiesterase 5/farmacologia , Citrato de Sildenafila , Dicloridrato de Vardenafila , Humanos
14.
J Pharm Biomed Anal ; 223: 115161, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36402125

RESUMO

Due to their health benefits, including regulating blood sugar and lowering cholesterol, berberine food supplements (FS) are widely used by consumers. This study aims to evaluate the quality of such products by proposing a new analytical methodology based on low-field NMR. Eighteen berberine FS were analyzed with both conventional (500 MHz) and benchtop (60 MHz) NMR spectrometers. Three quantitative 60 MHz 1H NMR methodologies were performed to determine berberine contents that were compared to those obtained at 500 MHz considered as reference measurements. To make the recording time of the spectra acquired at low field compatible with the requirements of a routine control, the quantification was carried out using a calibration curve established under conditions of incomplete relaxation of BrB protons. This methodology, applied to a test sample of 15 mg of FS, allowed to accurately measure a minimum quantity of berberine of ≈ 10 mg/capsule or tablet in 15 min. Regarding the FS, their labels are often unclear and/or incomplete for the consumer. Moreover, only 56 % of the FS analyzed actually contain the claimed quantity of berberine. The amounts of active they supply per day are extremely variable with only 39 % of the FS delivering a sufficient dose to achieve a hypoglycemic or hypolipidemic effect (1000-1500 mg/day based on literature data). These results show that health authorities should institute much stricter control and regulation over the production, labeling and marketing of berberine-based FS.


Assuntos
Berberina , Prótons , Espectroscopia de Prótons por Ressonância Magnética , Imageamento por Ressonância Magnética , Suplementos Nutricionais
15.
Food Res Int ; 165: 112473, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869486

RESUMO

We investigated the possibility to use rapeseed as a main oil in ice cream formulations by changing its functionality when using different kinds of lipases. Through a 24 h-emulsification and a centrifugation, the modified oils were further used as functional ingredients. All lipolysis was first assessed as a function of time by 13C NMR, where triglycerides consumption and the formation of low-molecular polar lipids (LMPL: monoacylglycerol and free fatty acids, FFAs) were selectively identified and compared. The more the FFAs, the sooner the crystallization (from -55 to -10 °C) and the later the melting temperatures (from -17 to 6 °C) measured by differential scanning calorimetry. These modifications were exploited in ice cream formulations with a significant impact on overall hardness (range of 60-216 N) and flowing during defrosting (from 1.29 to 0.35g/min). The global behavior of products can be controlled by the composition of LMPL within oil.


Assuntos
Brassica napus , Sorvetes , Óleo de Brassica napus , Cristalização , Lipase , Ácidos Graxos não Esterificados
16.
Transl Res ; 251: 2-13, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35724933

RESUMO

Calcium accumulation in atherosclerotic plaques predicts cardiovascular mortality, but the mechanisms responsible for plaque calcification and how calcification impacts plaque stability remain debated. Tissue-nonspecific alkaline phosphatase (TNAP) recently emerged as a promising therapeutic target to block cardiovascular calcification. In this study, we sought to investigate the effect of the recently developed TNAP inhibitor SBI-425 on atherosclerosis plaque calcification and progression. TNAP levels were investigated in ApoE-deficient mice fed a high-fat diet from 10 weeks of age and in plaques from the human ECLAGEN biocollection (101 calcified and 14 non-calcified carotid plaques). TNAP was inhibited in mice using SBI-425 administered from 10 to 25 weeks of age, and in human vascular smooth muscle cells (VSMCs) with MLS-0038949. Plaque calcification was imaged in vivo with 18F-NaF-PET/CT, ex vivo with osteosense, and in vitro with alizarin red. Bone architecture was determined with µCT. TNAP activation preceded and predicted calcification in human and mouse plaques, and TNAP inhibition prevented calcification in human VSMCs and in ApoE-deficient mice. More unexpectedly, TNAP inhibition reduced the blood levels of cholesterol and triglycerides, and protected mice from atherosclerosis, without impacting the skeletal architecture. Metabolomics analysis of liver extracts identified phosphocholine as a substrate of liver TNAP, who's decreased dephosphorylation upon TNAP inhibition likely reduced the release of cholesterol and triglycerides into the blood. Systemic inhibition of TNAP protects from atherosclerosis, by ameliorating dyslipidemia, and preventing plaque calcification.


Assuntos
Aterosclerose , Calcinose , Dislipidemias , Placa Aterosclerótica , Camundongos , Humanos , Animais , Fosfatase Alcalina , Músculo Liso Vascular , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Aterosclerose/etiologia , Aterosclerose/prevenção & controle , Apolipoproteínas E , Triglicerídeos
17.
Anal Bioanal Chem ; 403(6): 1651-60, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22543712

RESUMO

Abdominal aortic aneurysm (AAA) is an important health problem, both because of AAA rupture and death and because of increased cardiovascular mortality. Identification of new biomarkers of AAA may suggest novel pathological mechanisms and targets for new medical treatments to slow AAA progression. Metabolic changes in AAA patients were mainly related to carbohydrate and lipid metabolism and many of these changes can be associated with a situation of insulin resistance (which can be related to metabolic syndrome) together with altered amino acid metabolism. For the first time, metabolites that can be associated with differential metabolism by the gut microflora of AAA patients have also been found. Moreover, aminomalonic acid in plasma has been shown to be the metabolite with the biggest difference between patients suffering from large aneurysm (>5 cm) and controls.


Assuntos
Aneurisma da Aorta Abdominal/sangue , Metabolômica , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética
18.
Phytochem Anal ; 23(4): 387-95, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22025447

RESUMO

INTRODUCTION: The quality control of Magnoliae officinalis Cortex, a commonly used traditional Chinese medicine, is currently based on the assay of the two active compounds, honokiol and magnolol, by TLC or HPLC. OBJECTIVE: To compare ¹H-NMR-based metabolomics with the HPLC method for controlling the quality of Magnoliae officinalis Cortex. To identify the metabolites contributing to the differences between the samples and to discriminate different medicinal parts and geographic origins of these samples by ¹H-NMR-based metabolomics. METHODOLOGY: ¹H-NMR and several multivariate analysis techniques were applied to analyse the extracts of 18 batches of Magnoliae officinalis Cortex commercial samples, and the contents of honokiol and magnolol in these samples were determined by HPLC. The correlation analysis between the data from ¹H-NMR and HPLC was performed with the mixOmics software based on an unsupervised method. RESULTS: Honokiol and magnolol were the main compounds responsible for the discrimination of samples from different batches, thus proving that the choice of these two compounds as markers for quality assessment by HPLC is relevant. The two sources of Magnoliae officinalis Cortex recorded in the Chinese Pharmacopoeia, Magnolia officinalis and Magnolia officinalis var. biloba, could be differentiated from ¹H-NMR data, but the pattern recognition analysis by PLS-DA was unsuccessful in discriminating samples from various geographical origins. CONCLUSION: The combination of ¹H-NMR that gives a comprehensive profile of the metabolites and HPLC that targets two biomarkers is an efficient means for a better quality control of Magnoliae officinalis Cortex.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Magnolia/química , Metabolômica/métodos , Software , Compostos de Bifenilo/química , China , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Ecossistema , Lignanas/química , Metaboloma , Análise Multivariada , Controle de Qualidade , Sensibilidade e Especificidade
19.
Food Chem ; 369: 130870, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34455323

RESUMO

Commercial oleogelators rich in monoglycerides (MGs) are complex mixtures of acylglycerides with variable gelling properties, depending on the oil used and their concentration. In this study we developed a chemometric approach to identify the key parameters involved in gelling process. Analytical parameters have been defined, using GC and NMR analysis to identify fatty acids and acylglycerides composing the mixtures. Specific acylglyceride families and compound ratios were calculated to streamline the analytical results. To determine the key analytical parameters, artificial neural networks were used in a QSPR study related to the gelling properties measured by rheology through oscillatory experiments. At low oleogelator concentrations, the MGs especially rich in C16:0 and the ratio of specific isomers both have a positive influence on G'. For high oleogelator concentrations, C18:0-rich acylglycerides and unsaturated/saturated fatty acid ratios have a positive influence on G'. Conversely, at low concentrations, C18:0-rich acylglycerides show a lesser effect on G'.


Assuntos
Ácidos Graxos Insaturados , Monoglicerídeos , Ácidos Graxos , Humanos , Óleo de Brassica napus , Reologia
20.
J Pharm Biomed Anal ; 212: 114631, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35231794

RESUMO

Due to the numerous potential health benefits of Curcuma, turmeric dietary supplements (DS) are among the top selling products. To assess the quality of these formulations, thirty Curcuma DS along with five standard Curcuma rhizomes were analyzed with UHPLC-MS and 1H NMR. The chemometric treatment of the UHPLC-MS spectra showed a significant variability of their chemical composition that was confirmed by 1H NMR which allowed the absolute quantification of the Curcuma major bioactive components, i.e. curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin), and turmerones (aryl-, α- and ß-) as well as piperine, a commonly associated curcumin bioavailability enhancer: respectively 3.5-556, 0-8.6, 0.18-8.1 mg/capsule or tablet. The comparison of the actual and claimed quantities of curcuminoids and piperine showed that 58% of the DS contained the expected amounts of actives.


Assuntos
Curcuma , Curcumina , Cromatografia Líquida , Curcuma/química , Curcumina/análise , Diarileptanoides , Suplementos Nutricionais/análise , Extratos Vegetais/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas em Tandem
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa