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1.
Sci Rep ; 9(1): 9343, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249327

RESUMO

A joint metabolomic and lipidomic workflow is used to account for a potential effect of millimeter waves (MMW) around 60 GHz on biological tissues. For this purpose, HaCaT human keratinocytes were exposed at 60.4 GHz with an incident power density of 20 mW/cm², this value corresponding to the upper local exposure limit for general public in the context of a wide scale deployment of MMW technologies and devices. After a 24h-exposure, endo- and extracellular extracts were recovered to be submitted to an integrative UPLC-Q-Exactive metabolomic and lipidomic workflow. R-XCMS data processing and subsequent statistical treatment led to emphasize a limited number of altered features in lipidomic sequences and in intracellular metabolomic analyses, whatever the ionization mode (i.e 0 to 6 dysregulated features). Conversely, important dysregulations could be reported in extracellular metabolomic profiles with 111 and 99 frames being altered upon MMW exposure in positive and negative polarities, respectively. This unexpected extent of modifications can hardly stem from the mild changes that could be reported throughout transcriptomics studies, leading us to hypothesize that MMW might alter the permeability of cell membranes, as reported elsewhere.


Assuntos
Permeabilidade da Membrana Celular/efeitos da radiação , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Metaboloma , Metabolômica , Ondas de Rádio , Biomarcadores , Biologia Computacional/métodos , Humanos , Lipidômica , Metabolômica/métodos , Técnicas de Diagnóstico Molecular , Ondas de Rádio/efeitos adversos , Reprodutibilidade dos Testes
2.
Artigo em Inglês | MEDLINE | ID: mdl-29660668

RESUMO

To assess the presence of prohibited anabolic substances used to promote growth in livestock, calf urine is the most relevant matrix. However, the sample preparation methods (required to remove unwanted matrix components and fractionate isobaric species that may be unresolved by gas chromatography- mass spectrometry GC/MS) are long and complex. In this context, semi-preparative supercritical fluid chromatography (SFC) was considered to possibly simplify the sample preparation in reducing the number of procedures. Fifteen stationary phases were screened with SFC combined with UV and evaporative light-scattering detection (ELSD), among which two columns (Cosmosil π-NAP and Princeton DIOL) were retained for their ability to isolate steroid hormones from other matrix components and, for the second column, for the additional possibility to fractionate steroid hormones into different families (estrogens, mono-hydroxylated and di-hydroxylated androgens). The fractions were further analysed with GC/MS showing the benefit of class fractionation. The final method allows for significant time, solvent and money savings compared to the previously widely used method (solid-phase extraction combined with semi-preparative high-performance liquid chromatography).


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Congêneres da Testosterona/urina , Drogas Veterinárias/urina , Animais , Bovinos
3.
J Proteome Res ; 17(3): 1146-1157, 2018 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-29430917

RESUMO

The glucose analogue 2-deoxyglucose (2-DG) impedes cancer progression in animal models and is currently being assessed as an anticancer therapy, yet the mode of action of this drug of high clinical significance has not been fully delineated. In an attempt to better characterize its pharmacodynamics, an integrative UPLC-Q-Exactive-based joint metabolomic and lipidomic approach was undertaken to evaluate the metabolic perturbations induced by this drug in human HaCaT keratinocyte cells. R-XCMS data processing and subsequent multivariate pattern recognition, metabolites identification, and pathway analyses identified eight metabolites that were most significantly changed upon a 3 h 2-DG exposure. Most of these dysregulated features were emphasized in the course of lipidomic profiling and could be identified as ceramide and glucosylceramide derivatives, consistently with their involvement in cell death programming. Even though metabolomic analyses did not generally afford such clear-cut dysregulations, some alterations in phosphatidylcholine and phosphatidylethanolamine derivatives could be highlighted as well. Overall, these results support the adequacy of the proposed analytical workflow and might contribute to a better understanding of the mechanisms underlying the promising effects of 2-DG.


Assuntos
Antineoplásicos/farmacologia , Ceramidas/metabolismo , Desoxiglucose/farmacologia , Glucosilceramidas/metabolismo , Queratinócitos/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Transformada , Ceramidas/análise , Cromatografia Líquida de Alta Pressão , Galactolipídeos/análise , Galactolipídeos/metabolismo , Glucosilceramidas/análise , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Espectrometria de Massas , Metabolômica/métodos , Fosfatidilcolinas/análise , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/análise , Fosfatidiletanolaminas/metabolismo
4.
Anal Bioanal Chem ; 407(15): 4473-84, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25736246

RESUMO

Profiling conjugated urinary steroids to detect anabolic-steroid misuse is recognized as an efficient analytical strategy in both chemical-food-safety and anti-doping fields. The relevance and robustness of such profiling rely on the analysis of glucuronide and sulfate steroids, which is expected to have properties including accuracy, specificity, sensitivity, and, if possible, rapidity. In this context, the ability of ultra-high-performance supercritical-fluid chromatography (UHPSFC) hyphenated tandem mass spectrometry (MS-MS) to provide reliable and accurate phase II analysis of steroids was assessed. Four stationary phases with sub-2 µm particles (BEH, BEH 2-ethyl-pyridine, HSS C18 SB, and CSH fluorophenyl) were screened for their capacity to separate several conjugated steroid isomers. Analytical conditions including stationary phase, modifier composition and percentage, back pressure, column temperature, and composition and flow rate of make-up solvent were investigated to improve the separation and/or the sensitivity. Thus, an analytical procedure enabling the analysis of eight glucuronide and 12 sulfate steroids by two different methods in 12 and 15 min, respectively, was optimized. The two procedures were evaluated, and UHPSFC-MS-MS analysis revealed its ability to provide sensitive (limits of quantification: 0.1 ng mL(-1) and 0.5 ng mL(-1) for sulfate and glucuronide steroids, respectively) and reliable quantitative performance (R(2) > 0.995, RSD < 20%, and bias < 30%) through the use of suitable labeled internal standards. Comparison with UHPLC-MS-MS was performed, and UHPSFC-MS-MS obtained better performance in terms of sensitivity. Finally, as a proof of concept, this so-called green technology was used in a chemical-food-safety context to profile steroid conjugates in urine samples from bovines treated with estradiol. Graphical Abstract Glucuronide and sulfate steroids analysis in urine by ultra-high performance supercritical fluid chromatography hyphenated tandem mass spectrometry.


Assuntos
Anabolizantes/urina , Bovinos/urina , Cromatografia Líquida de Alta Pressão/métodos , Estradiol/urina , Glucuronídeos/urina , Esteroides/urina , Espectrometria de Massas em Tandem/métodos , Animais , Limite de Detecção , Sulfatos/urina
5.
Anal Bioanal Chem ; 407(15): 4343-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25716468

RESUMO

Recombinant bovine somatotrophin (rbST) is widely used in some countries to increase milk production. Since 1994, both marketing and use of this substance have been prohibited within the European Union. In this context, the targeted plasma biochemical and hormonal profiling was assessed as a potential screening strategy to highlight rbST (ab)use in cattle. Twenty-one routinely measured clinical blood parameters, representative of main biological profiles (energetic, proteic, etc.), were measured in the plasma of six lactating cows before and after rbST treatment throughout a 23-day study period. Appropriate multivariate statistical analyses [principal component analysis (PCA) and orthogonal partial least square (OPLS)] enabled discriminating animal samples before and after treatment (days 0 vs. 2 to 9, P = 2.10(-9)) and highlighted the five most relevant blood parameters in this discrimination. Based on each five-analyte contribution, a simple mathematically weighted equation was suggested to predict the status of samples. A suspicious threshold was proposed, and the model was further tested with the status prediction of the supplementary samples from untreated (n = 20) and treated cows (n = 22). The calculated false-positive (10%) and false-negative (4.5%) rates were in accordance with the EU requirements for screening methods. Although the model needs to be further validated with additional samples, such targeted plasma biochemical and hormonal profiling already appears as a potential promising screening strategy to highlight rbST (ab)use in cattle.


Assuntos
Bovinos/sangue , Hormônio do Crescimento/sangue , Detecção do Abuso de Substâncias , Animais , Feminino , Lactação , Leite/metabolismo , Modelos Estatísticos , Análise Multivariada
6.
Drug Test Anal ; 7(7): 603-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25262809

RESUMO

High throughput screening is essential for doping, forensic, and food safety laboratories. While hyphenated chromatography-mass spectrometry (MS) remains the approach of choice, recent ambient MS techniques, such as direct analysis in real time (DART), offer more rapid and more versatile strategies and thus gain in popularity. In this study, the potential of DART hyphenated with Orbitrap-MS for fast identification and quantification of 21 anabolic steroid esters has been evaluated. Direct analysis in high resolution scan mode allowed steroid esters screening by accurate mass measurement (Resolution = 60 000 and mass error < 3 ppm). Steroid esters identification was further supported by collision-induced dissociation (CID) experiments through the generation of two additional ions. Moreover, the use of labelled internal standards allowed quantitative data to be recovered based on isotopic dilution approach. Linearity (R(2) > 0.99), dynamic range (from 1 to 1000 ng mL(-1) ), bias (<10%), sensitivity (1 ng mL(-1) ), repeatability and reproducibility (RSD < 20%) were evaluated as similar to those obtained with hyphenated chromatography-mass spectrometry techniques. This innovative high throughput approach was successfully applied for the characterization of oily commercial preparations, and thus fits the needs of the competent authorities in the fight against forbidden or counterfeited substances.


Assuntos
Anabolizantes/análise , Sistemas Computacionais , Dopagem Esportivo , Esteroides/análise , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida de Alta Pressão/métodos , Ésteres/análise , Detecção do Abuso de Substâncias/instrumentação
7.
Anal Chem ; 86(12): 5649-55, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24796942

RESUMO

Recent developments in ambient mass spectrometry (AMS), such as atmospheric solids analysis probe (ASAP) mass spectrometry, open a whole new range of possibilities to screen for drug preparations. In this study, the potential of ASAP for the rapid identification and quantification of anabolic steroid esters has been evaluated. These compounds are known to be used both in human and in food producing animals to enhance performances and to improve the rate of growth, respectively. Using a triple quadrupole (QqQ) MS instrument, mechanism of ionization and fragmentation in both positive and negative mode were studied for a range of 21 selected steroid esters (based on testosterone, estradiol, nandrolone, and boldenone) which highlighted common neutral mass loss of 96.1, thus allowing rapid screening in minutes to reveal steroid ester presence with minimal sample preparation. Ester identification is further achieved through an efficient 2 min workflow on a QqQ MS instrument. Moreover, the use of isotope labeled internal standards permitted the quantification of the corresponding steroid esters in selected reaction monitoring (SRM) mode, for the first time in ASAP. This approach was successfully applied for characterization of oily commercial preparations. These results open new perspectives in hormone (and drug) rapid analysis by ASAP-MS in the near future.


Assuntos
Anabolizantes/análise , Ensaios de Triagem em Larga Escala , Preparações Farmacêuticas/química , Esteroides/análise , Ésteres , Temperatura Alta
8.
J Chromatogr A ; 1270: 51-61, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23195708

RESUMO

The use of anabolic substances to promote growth in livestock is prohibited within the European Union as laid down in Directive 96/22/EC. Nowadays, efficient methods such as steroid profiling or isotopic deviation measurements allow to control natural steroid hormones abuse. In both cases, urine is often selected as the most relevant matrix and, due to its relatively high content of potential interferents, its preparation before analysis is considered as a key step. In this context, the use of a selective sorbent such as molecularly imprinted polymer (MIP) was investigated. A MIP was synthesized based on 17ß-estradiol, methacrylic acid and acetonitrile as template, monomer and porogen, respectively. Two approaches were then tested for non-conjugated (aglycons and glucuronides deconjugated) steroid purification: (i) molecularly imprinted solid phase extraction (MISPE) and (ii) semi-preparative supercritical fluid chromatography with a commercial MIP as stationary phase (SFC-MIP). Parameters for both approaches were optimized based on the main bovine metabolites of testosterone, estradiol, nandrolone and boldenone. The MISPE protocol developed for screening purposes allowed satisfactory recoveries (upper 65% for the 12 target steroids) with sufficient purification for gas chromatography-mass spectrometry (GC-MS) analysis. For confirmatory purposes, the use of isotopic ratio mass spectrometry (IRMS) requires a higher degree of purity of the target compounds, which can be reached by the SFC-MIP protocol with three steps less compared to the official and current method. Purity, concentration and absence of isotopic fractionation of target steroids extracted from urine of treated cattle (treated with testosterone, estradiol, androstenedione, and boldenone) allowed the measurement of (13)C/(12)C isotopic ratios of corresponding metabolites and endogenous reference compounds (ERC) and proved the relevance of the strategy.


Assuntos
Criação de Animais Domésticos/normas , Impressão Molecular/métodos , Esteroides/urina , Drogas Veterinárias/urina , Acetonitrilas/química , Animais , Bovinos , Cromatografia com Fluido Supercrítico/métodos , Inocuidade dos Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Metanol/química , Polímeros/química , Extração em Fase Sólida/métodos , Esteroides/isolamento & purificação , Drogas Veterinárias/isolamento & purificação
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