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1.
Anal Sci ; 40(1): 85-91, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37843729

RESUMO

Rapid and effective separation of nucleotides (NTs) and their derivatives is crucial for studying their physiological functions. In this work, we comprehensively evaluated the separation ability of a zwitterionic hydrophilic monolith, i.e., poly(N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl)ammonium betaine-co-N,N'-methylenebisacrylamide) (poly(SPP-co-MBA)) for NTs analysis, including its selectivity, chemical stability under extremely basic condition and compatibility with hydrophilic interaction liquid chromatography (HILIC) coupled with mass spectrometry (HILIC-MS). The poly(SPP-co-MBA) monolith exhibited excellent chemical stability, as evidenced by the low relative standard deviation of retention time (0.16-1.05%) after 4000 consecutive injections over one month under strong alkaline elution condition (pH 10). After optimizing the separation conditions, including buffer pH and concentration, organic solvent content and column temperature, four nucleoside triphosphates, five nucleoside diphosphates and five nucleoside monophosphates were baseline separated within 7 min. Additionally, the mixtures containing one nucleoside and its corresponding mono-, di-, and triphosphates were baseline separated within only 3 min, respectively. It is good HILIC-MS compatibility was also confirmed by the satisfactory peak shape and high response of nine NTs. Overall, the proposed poly(SPP-co-MBA) monolith exhibited good mechanical stability and compatibility of HILIC-MS, making it a promising technique for NTs analysis.


Assuntos
Nucleosídeos , Nucleotídeos , Nucleotídeos/análise , Nucleosídeos/análise , Nucleosídeos/química , Cromatografia Líquida/métodos , Betaína/química , Interações Hidrofóbicas e Hidrofílicas
2.
Food Res Int ; 158: 111461, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35840193

RESUMO

The biochemical properties and microstructural changes of freeze-dried Japanese scallop (Patinopecten yessoensis) striated muscle during room temperature storage and rehydration were investigated. The results showed that the content of ATP in freeze-dried scallop muscle remained stable with no significant difference (p > 0.05). However, ATP was rapidly decomposed and AMP accumulated within 1.5 min of rehydration, and HxR and Hx were gradually produced from AMP decomposition with the extension of rehydration time. Besides, the results of chymotryptic digestion patterns demonstrated that the rod of myosin was unstable after dehydration, reflecting lower salt solubility than that of frozen-thawed scallop. In contrast, the myosin subfragment-1 (S-1) was stable, as indicated by the constant of Ca2+-ATPase activity of freeze-dried scallops throughout the storage and rehydration (p > 0.05). Furthermore, the microstructural analysis revealed that the Z line of the freeze-dried scallop was broken after dehydration process. This study might be useful for developing high-quality dehydrated scallops in the future.


Assuntos
Músculo Estriado , Pectinidae , Monofosfato de Adenosina/análise , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/metabolismo , Animais , Desidratação/metabolismo , Hidratação , Músculo Esquelético/química , Nucleotídeos/análise , Pectinidae/química , Proteínas/análise
3.
Biochim Biophys Acta Mol Cell Res ; 1869(5): 119237, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35150807

RESUMO

Nucleotides are released from all cells through regulated pathways or as a result of plasma membrane damage or cell death. Outside the cell, nucleotides act as signalling molecules triggering multiple responses via specific plasma membrane receptors of the P2 family. In the nervous system, purinergic signalling has a key function in neurotransmission. Outside the nervous system, purinergic signalling is one of the major modulators of basal tissue homeostasis, while its dysregulation contributes to the pathogenesis of various disease, including inflammation and cancer. Pre-clinical and clinical evidence shows that selective P2 agonists or antagonists are effective treatments for many pathologies, thus highlighting the relevance of extracellular nucleotides and P2 receptors as therapeutic targets.


Assuntos
Nucleotídeos/metabolismo , Transdução de Sinais , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Membrana Celular/metabolismo , Humanos , Pneumopatias/metabolismo , Pneumopatias/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Nucleotídeos/análise , Receptores Purinérgicos P2X/metabolismo , Receptores Purinérgicos P2Y/metabolismo
4.
Sci Total Environ ; 817: 152510, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-34968603

RESUMO

Nucleotides, as the basic building blocks of nucleic acids, widely exist in aqueous environment. In this study, we developed a solid phase extraction-high performance liquid chromatography-tandem mass spectrometry (SPE-UPLC-MS/MS) method for the analysis of 5'-adenosine monophosphate (AMP), 5'-uridine monophosphate (UMP), 5'-cytidine monophosphate (CMP) and 5'-guanosine monophosphate (GMP). The method achieved limits of detection (LODs) of 0.1-1.0 ng/L, and recoveries of 85-95% for the four tested nucleotides. The occurrence and concentrations of the four nucleotides in water from eight representative drinking water treatment and distribution systems in China were determined using this method. All four nucleotides were detectable in water treatment plant (WTP) influent and effluent, at concentrations of up to 30 ng/L and with occurrence frequency of around 90%. The concentrations of identified nucleotides increased 3-10 times after 10 km of water age in the water distribution system. Biological filters and coagulation increased the concentrations of nucleotides, conversely, active carbon, ozonation, and ultrafiltration membrane removed nucleotides in water. The effects of active carbon and coagulation were further confirmed using laboratory-controlled experiment. In addition, monochlorinated nucleotides were identified as the chlorination products of nucleotides.


Assuntos
Água Potável , Poluentes Químicos da Água , Purificação da Água , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Água Potável/análise , Nucleotídeos/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise
5.
Food Chem ; 362: 130192, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34090042

RESUMO

Seven enzyme groups were applied to hydrolyze broken fruiting bodies of morel mushroom (Morchella sextelata) to extract umami substances. Physical-chemical properties, as well as compositions and concentrations of quintessential umami compounds of morel hydrolysates were analyzed. Electronic tongue and electronic nose were used to evaluate the sensory characteristics. The results suggested that peptides below 3 kDa showed the highest correlation with umami taste. Morel hydrolysate obtained from Neutrase-Flavourzyme (NF) combination contained the most contents of small peptides (<3 kDa), free amino acids (224.83 ± 0.87 mg/g), as well as flavor 5'-nucleotides (4.84 ± 0.32 mg/g), giving the best overall flavor properties. The reaction conditions of NF were optimized by response surface methodology (RSM). The highest degree of hydrolysis (DH) was up to 36.64%. An enzymatic hydrolysis approach was established to develop novel flavor products with high umami and low bitter taste from morel mushroom.


Assuntos
Ascomicetos/química , Enzimas/química , Aromatizantes/química , Paladar , Aminoácidos/análise , Nariz Eletrônico , Proteínas Fúngicas/química , Hidrólise , Nucleotídeos/análise , Nucleotídeos/química , Peptídeos/análise , Peptídeos/química , Hidrolisados de Proteína/química
6.
Food Chem ; 343: 128409, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33218856

RESUMO

We investigated the effect of temporary rearing in brackish water on the taste quality in meat of crab cooked. The main salinity-responsive factors included 5'-nucleotides and free amino acids (FAAs) in crab meat that were identified using tri-step infrared spectroscopy. Compared to the fresh water group, the contents of 5'-adenosine monophosphate and 5'-inosine monophosphate in the brackish water group significantly increased in the 2nd week and decreased in the 6th week, respectively. The contribution ratio of umami FAAs increased from 8.1 to 13.5% in the 4th week in the brackish water group, showing maximum value of equivalent umami concentration. Moreover, Ca2+ and Cl- contents significantly increased in the 4th and 6th weeks, respectively (P < 0.05). Infrared spectroscopy was an effective method to identify the taste components. With respect to the taste quality, four weeks were determined as the best period for temporary rearing of the crab in brackish water.


Assuntos
Aquicultura/métodos , Braquiúros , Águas Salinas/química , Frutos do Mar , Paladar , Monofosfato de Adenosina/análise , Aminoácidos/análise , Animais , Culinária/métodos , Inosina Monofosfato/análise , Masculino , Nucleotídeos/análise , Espectrofotometria Infravermelho
7.
J Hosp Infect ; 106(2): 348-356, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32768608

RESUMO

BACKGROUND: Adenosine triphosphate (ATP) test based on one nucleotide has been applied as point-of-care testing (POCT) for bacterial contamination in the medical and food industries. Hypothetically, testing three adenylate nucleotides (A3) may provide better detection of duodenoscope bacterial contamination than ATP test. AIM: To evaluate performance characteristics and optimal cut-off value of A3 and ATP tests in predicting bacterial contamination of duodenoscopes. METHODS: Four hundred duodenoscope samples obtained after 100 endoscopic retrograde cholangiopancreatography procedures were randomized into group A (A3 test) or B (ATP test). Samples were collected from the elevator at the four-step cleaning process of duodenoscope. We defined the new cut-off value of the test for reaching 100% negative predictive value (NPV) from our receiver operating characteristic (ROC). FINDINGS: Using the cultures from the four-step cleaning process as the reference, the areas under ROC (AUROC) were 0.83 and 0.84 for group A (N = 200) and group B (N = 200), respectively. Using the cultures from post-high-level disinfection (HLD) as the reference, the AUROC were 0.35 and 0.74 for group A (N = 50) and group B (N = 50), respectively. We investigated ATP as a POCT after HLD with a new cut-off value of 40 RLU. However, this threshold did not allow detection of low numbers of bacteria. CONCLUSION: A3 and ATP tests provide good performances in predicting bacterial contamination of duodenoscopes for the four-step cleaning process. The ATP <40 RLU is helpful as a POCT after HLD; however, the limitation of this cut-off value is its inability to detect low numbers of bacteria.


Assuntos
Trifosfato de Adenosina/análise , Bactérias/isolamento & purificação , Desinfecção/normas , Duodenoscópios/normas , Nucleotídeos/análise , Testes Imediatos , Bactérias/classificação , Infecção Hospitalar/prevenção & controle , Desinfecção/métodos , Duodenoscópios/microbiologia , Contaminação de Equipamentos/prevenção & controle , Reutilização de Equipamento , Humanos
8.
Artigo em Inglês | MEDLINE | ID: mdl-32446186

RESUMO

Purinergic signalling is involved in physiological processes, particularly during ischemia-reperfusion injuries for which it has a protective effect. The purpose of this work was to develop a method for simultaneous quantification of eight nucleotides and adenosine in biological matrices by liquid chromatography coupled with high-resolution mass spectrometry. A method was developed that was sufficiently robust to quantify the targeted analytes in 20 min with good sensitivity. Analysis of extracellular media from cultured endothelial cells detected the release of nucleotides and adenosine during 2 h of hypoxia. The quantification of cylic adenosine monophosphate (cAMP) allowed to establish a dose-response curve after receptor stimulation. Therefore, our method allows us to study the involvement of nucleotides in various processes in both the intracellular and extracellular compartment.


Assuntos
Adenosina/análise , Cromatografia Líquida de Alta Pressão/métodos , Meios de Cultura/química , Espectrometria de Massas/métodos , Nucleotídeos/análise , Animais , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Cinética , Limite de Detecção , Ratos , Reprodutibilidade dos Testes
9.
Food Chem ; 320: 126656, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32224424

RESUMO

The influence of temperature-time combinations on non-volatile compound and taste traits of beef semitendinosus muscles tested by the electronic tongue was studied. Single-stage sous-vide at 60 and 70 °C (6 and 12 h), and two-stage sous-vide that sequentially cooked at 45 °C (3 h) and 60 °C (either 3 or 9 h) were compared with traditional cooking at 70 °C (30 min). Umami was better explained in the given model of partial least squares regression than astringency, sourness, saltiness, bitterness, and richness. Sous-vide at 70 °C for 12 h characterized the most umami, likely adenosine-5'-monophosphate (AMP) and guanosine-5'-monophosphate (GMP) as significant contributors. Two-stage sous-vide projected higher histidine, leucine, inosine, and hypoxanthine with the astringent and sour taste significant after 6 and 12 h cooking, respectively. Equivalent umami concentration (EUC) between umami amino acids and umami nucleotides showed a strong relationship to umami taste assessed by the electronic tongue.


Assuntos
Nariz Eletrônico , Análise de Alimentos/métodos , Carne Vermelha , Paladar , Monofosfato de Adenosina/análise , Aminoácidos/análise , Animais , Bovinos , Temperatura Baixa , Culinária , Guanosina Monofosfato/análise , Calefação , Hipoxantina/análise , Masculino , Nucleotídeos/análise , Carne Vermelha/análise , Temperatura , Compostos Orgânicos Voláteis/análise
10.
Nucleic Acids Res ; 48(9): e53, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32187374

RESUMO

Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is used to identify genome-wide DNA regions bound by proteins. Given one ChIP-seq experiment with replicates, binding sites not observed in all the replicates will usually be interpreted as noise and discarded. However, the recent discovery of high-occupancy target (HOT) regions suggests that there are regions where binding of multiple transcription factors can be identified. To investigate ChIP-seq variability, we developed a reproducibility score and a method that identifies cell-specific variable regions in ChIP-seq data by integrating replicated ChIP-seq experiments for multiple protein targets on a particular cell type. Using our method, we found variable regions in human cell lines K562, GM12878, HepG2, MCF-7 and in mouse embryonic stem cells (mESCs). These variable-occupancy target regions (VOTs) are CG dinucleotide rich, and show enrichment at promoters and R-loops. They overlap significantly with HOT regions, but are not blacklisted regions producing non-specific binding ChIP-seq peaks. Furthermore, in mESCs, VOTs are conserved among placental species suggesting that they could have a function important for this taxon. Our method can be useful to point to such regions along the genome in a given cell type of interest, to improve the downstream interpretative analysis before follow-up experiments.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Linhagem Celular Tumoral , Cromatina/metabolismo , Células-Tronco Embrionárias/metabolismo , Evolução Molecular , Variação Genética , Genômica/métodos , Humanos , Células K562 , Células MCF-7 , Camundongos , Nucleotídeos/análise , Análise de Componente Principal , Regiões Promotoras Genéticas , Estruturas R-Loop
11.
Artigo em Inglês | MEDLINE | ID: mdl-32222674

RESUMO

The pyridine nucleotides nicotineamide adenine dinucleotide (NAD) and nicotineamide adenine dinucleotide phosphate (NADP) are conserved coenzymes across all domains of life, and are involved in more than 200 different hydride transfer reactions supporting essential catabolic and anabolic functions. The intracellular levels of these metabolites, and the ratio of their oxidized to reduced forms regulate an extensive network of reactions ranging beyond metabolism. Hence, monitoring their intracellular levels provides information about, but not limited to, the metabolic state of a cell or tissue. Interconversion between oxidized and reduced forms, varying pH liability and varying intracellular concentrations of the different species leaves absolute quantification of the pyridine nucleotides analytically challenging. These polar metabolites are poorly retained on conventional reverseed-phase stationary phases without ion-pair reagents that contaminates the LC-system. Herein we demonstrate that zwitterionic HILIC-tandem mass spectroemtry can be applied to successfully resolve the pyridine nucleotides in biological extracts in a fast, robust and highly sensitive way. The presented method applies isotope dilution to compensate potential loss of these labile metabolites and is validated for low, medium and high biomass samples of two popular biological model systems; Escherichia coli and the human cell line JJN-3. High stability and rapid sample preparation without solvent removal allows for long sequence runs, making this method ideal for high-throughput analysis of biological extracts.


Assuntos
Isótopos/análise , Nucleotídeos/análise , Extratos Vegetais/análise , Piridinas/análise , Nucleotídeos de Adenina/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Escherichia coli , Humanos , Limite de Detecção , NAD/metabolismo , Oxirredução , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
12.
J Chromatogr A ; 1619: 460914, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32008820

RESUMO

Recently, ion chromatography coupled with mass spectrometry has been used for the determination of anionic metabolites. However, connection with a mass spectrometer in this method is not straightforward because backpressure produced by the addition of a make-up solution often affects the peak resolutions of the target metabolites. To overcome this problem, we developed a capillary ion chromatography-mass spectrometry method utilizing a double coaxial electrospray ionization sprayer. This method was not affected by backpressure and the number of theoretical plates was about three times that of a conventional sprayer. Under optimized conditions, 44 anionic metabolites, including organic acids, sugar phosphates, nucleotides, and cofactors, were successfully separated and selectively detected with a Q Exactive mass spectrometer. The calibration curves of the tested metabolites showed excellent linearity within the range of 1-100,000 nmol/L and the correlation coefficient was greater than 0.991. The detection limits for these metabolites were between 1 and 500 nmol/L (0.4 and 200 fmol). The developed method was applied to the quantitation of anionic metabolites in cultured cancer cell samples with tumor necrosis factor (TNF)-α stimulation. This allowed for the successful determination of 105 metabolites. The levels of tricarboxylic acid cycle intermediates changed significantly after TNF-α stimulation. These results demonstrate that the developed method is a promising new tool for comprehensive analysis of anionic metabolites.


Assuntos
Espectrometria de Massas por Ionização por Electrospray/métodos , Ácidos/análise , Ácidos/isolamento & purificação , Ânions/química , Calibragem , Cromatografia/métodos , Humanos , Limite de Detecção , Neoplasias/metabolismo , Nucleotídeos/análise , Nucleotídeos/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/normas , Fator de Necrose Tumoral alfa/farmacologia
13.
Sci Rep ; 10(1): 945, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969599

RESUMO

Oolong tea is famous for its characteristic of durably brewing. To explore suitable brewing cuppages and the scientific methods to brew Oolong tea in multiple steeping process. Dahongpao tea (Zhengyan, Banyan and Zhouyan tea) is well known Oolong tea variety, brewed at 14 times and assessed its chemical composition, infusion colour and sensory quality in different brewing intervals. The results showed that Zhengyan tea (A3) had the best quality of steeping among the chosen tea. It could be brewed up to 10 cuppages with 80% sensory score. The chemical composition and tea infusion colour strength were higher in Zhengyan tea. Though, 70% caffeine leached within first three steeping. The Forest regression model revealed that the suitable brewing time ranges between 4 and 10 in the chosen Dahongpao tea variety. This study provides a scientific method and suitable steeping times for the drinking of different Dahongpao tea through dynamic analysis of quantity of chemical composition, infusion colour strength and sensory quality.


Assuntos
Camellia sinensis/química , Cor , Culinária/métodos , Análise de Alimentos , Qualidade dos Alimentos , Paladar , Chá/química , Aminoácidos/análise , Cafeína/análise , Carboidratos/análise , Catequina/análise , Nucleotídeos/análise , Polifenóis/análise
14.
Electrophoresis ; 41(5-6): 360-369, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31907937

RESUMO

Negative ion mode nano-ESI-MS is often considered for the analysis of acidic compounds, including nucleotides. However, under high aqueous separation conditions, corona discharge is frequently observed at emitter tips, which may result in low ion abundances and reduced nano-ESI needle emitter lifetimes. In this work, we introduce a sheathless CE-MS method for the highly efficient and sensitive analysis of nucleotides employing ESI in positive ion mode, thereby fully circumventing corona discharge. By using a background electrolyte of 16 mM ammonium acetate (pH 9.7) a mixture of 12 nucleotides, composed of mono-, di-, and tri-phosphates, could be efficiently analyzed with plate numbers per meter above 220 000 and with LODs in the range from 0.06 to 1.3 nM, corresponding to 0.4 to 8.6 attomole, when using an injection volume of about 6.5 nL only. The utility of the method was demonstrated for the profiling of nucleotides in low numbers of mammalian cells using HepG2 cells as a model system. Endogenous nucleotides could be efficiently analyzed in extracts from 50 000 down to 500 HepG2 cells only. Moreover, apart from nucleotides, also some nicotinamide-adenine dinucleotides and amino acids could be analyzed under these conditions, thereby clearly illustrating the utility of this approach for metabolic profiling of low amounts of biological material.


Assuntos
Eletroforese Capilar/métodos , Nucleotídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Células Hep G2 , Humanos , Limite de Detecção , Modelos Lineares , Metaboloma , Reprodutibilidade dos Testes
15.
J Pharm Biomed Anal ; 180: 113041, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31855724

RESUMO

Gastric cancer (GC) is the third most common cause of cancer death worldwide, and the incidence of GC is higher in males than females. To investigate the gastric cellular response to hormone therapy, we developed a cell pseudotargeted metabolomics method based on liquid chromatography-hybrid triple quadrupole linear ion trap mass spectrometry (LC-QTRAP MS). Chromatographic separation, sample analysis and metabolite extraction were optimized in an integrated manner. The established pseudotargeted method, which combined nontargeted and targeted analyses, exhibited high selectivity, good repeatability and wide metabolome coverage. The method was then applied to discover differential metabolites from hormone-stimulated gastric cancer cells compared with the controls for the first time. The results demonstrated that hormone had subtle but phenotypically important alterations in nucleotide metabolism, amino acid metabolism, glycolysis, tricarboxylic acid (TCA) cycle, aminoacyl-tRNA biosynthesis and so on, which indicate that the developed method is a powerful tool for effective screening of endogenous polar metabolites in cell samples.


Assuntos
Hormônios/metabolismo , Metabolômica/métodos , Neoplasias Gástricas/metabolismo , Espectrometria de Massas em Tandem/métodos , Aminoácidos/análise , Aminoácidos/metabolismo , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Ciclo do Ácido Cítrico/efeitos dos fármacos , Di-Hidrotestosterona/metabolismo , Estradiol/metabolismo , Glicólise/efeitos dos fármacos , Humanos , Nucleotídeos/análise , Nucleotídeos/metabolismo , RNA de Transferência/análise , RNA de Transferência/biossíntese
16.
Int J Radiat Oncol Biol Phys ; 105(4): 843-851, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31352081

RESUMO

PURPOSE: To identify metabolomic biomarkers of acute radiation exposure in saliva that show time-dependent changes. METHODS AND MATERIALS: Nonhuman primates were exposed to 4 Gy of total body irradiation with γ-rays. Saliva was collected from 7 animals twice before and at days 1, 3, 5, 7, 15, 21, 28, and 60 after irradiation. Profiling was conducted with liquid chromatography time-of-flight mass spectrometry. Multivariate data analysis and potential biomarker identification was conducted through random Forests and the software MetaboAnalyst. Candidate biomarkers were validated through tandem mass spectrometry, and receiver operating characteristic curves were constructed to show the diagnostic ability of the signature over time. RESULTS: Untargeted metabolomic analysis revealed significant and persistent effects up to the 60 days evaluated in this study. Biomarkers spanning primarily amino acids and nucleotides were identified, with a significant number showing long-term responses. Fifteen biomarkers showed high statistical significance in the first week after irradiation and 16 at >7 days after irradiation (false discovery rate-adjusted P < .05). The combination of the biomarkers in a single biosignature was able to accurately show the diagnostic ability of the signature in a binary classifier system with receiver operating characteristic curves. CONCLUSIONS: Radiation can alter the metabolome in saliva, and metabolomics could effectively be used to monitor radiation responses, as a biodosimetry method, in the event of a radiological incident. Saliva metabolomics also has potential relevance in a clinical setting.


Assuntos
Metaboloma/efeitos da radiação , Metabolômica/métodos , Saliva/efeitos da radiação , Irradiação Corporal Total , Aminoácidos/análise , Animais , Biomarcadores/análise , Cromatografia Líquida , Feminino , Raios gama , Macaca mulatta , Masculino , Análise Multivariada , Nucleotídeos/análise , Curva ROC , Doses de Radiação , Exposição à Radiação , Saliva/metabolismo , Purificação por Afinidade em Tandem , Fatores de Tempo
17.
J Pharm Biomed Anal ; 174: 432-440, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31220701

RESUMO

A novel, simple, and efficacious analytical method for determining of nucleotides in Anoectochilus roxburghii (Wall.) Lindl (A. roxburghii) was developed. Magnetic dispersive solid-phase micro-extraction (MDSPME) combined with high-performance liquid chromatography was applied for extraction and determination of three nucleotides, such as adenosine-5'-monophosphate (AMP), uridine-5'-monophosphate (UMP) and guanosine-5'-monophosphate (GMP) in A. roxburghii from different sources. The structure and morphology of magnetic nanoparticles, Fe3O4@GO, were illustrated by Fourier-transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Thermagravimetric analysis (TGA) techniques. The effects of different extraction conditions on extraction efficiency were investigated and optimized. The optimum extraction conditions were performed as follows: 40.0 mg Fe3O4@GO were dispersed in 30 mL adsorption solution (pH 3.50, 2 µg/mL), 50 mM NaOH was employed for elution with 12 min of ultra-sonication at 40 °C. Under the aforementioned extraction conditions, the Fe3O4@GO nano-adsorbent obtained an excellent adsorption property. The corresponding linearity range for all three analytes exhibited a good linearity (r2 ≥ 0.9982) and notable added recoveries ranging from 88.4% to 109.8%, whereas the limit of quantitation was between 0.8-8 ng/mL. The enrichment factors (EF) were between 174 and 255. The proposed method showed the advantages of full purification, high EF, simplicity, and good recovery. The method was also successfully applied to nucleotides extraction and determination in A. roxburghii, showing superior reproducibility and high sensitivity. Based on this, the method could be expected to provide a novel experimental means and developmental direction for improving pretreatment and purification of nucleotides, reducing matrix effects as much as possible, in traditional Chinese medicinal materials or biological specimens.


Assuntos
Cromatografia Líquida de Alta Pressão , Nucleotídeos/análise , Orchidaceae/química , Microextração em Fase Sólida , Adsorção , Medicamentos de Ervas Chinesas/análise , Concentração de Íons de Hidrogênio , Ferro/química , Limite de Detecção , Magnetismo , Nanopartículas de Magnetita/química , Espectrometria de Massas , Medicina Tradicional Chinesa , Nanopartículas Metálicas/química , Solventes , Sonicação , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Biol Chem ; 294(27): 10564-10578, 2019 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-31138644

RESUMO

Cellular senescence is a mechanism by which cells permanently withdraw from the cell cycle in response to stresses including telomere shortening, DNA damage, or oncogenic signaling. Senescent cells contribute to both age-related degeneration and hyperplastic pathologies, including cancer. In culture, normal human epithelial cells enter senescence after a limited number of cell divisions, known as replicative senescence. Here, to investigate how metabolic pathways regulate replicative senescence, we used LC-MS-based metabolomics to analyze senescent primary human mammary epithelial cells (HMECs). We did not observe significant changes in glucose uptake or lactate secretion in senescent HMECs. However, analysis of intracellular metabolite pool sizes indicated that senescent cells exhibit depletion of metabolites from nucleotide synthesis pathways. Furthermore, stable isotope tracing with 13C-labeled glucose or glutamine revealed a dramatic blockage of flux of these two metabolites into nucleotide synthesis pathways in senescent HMECs. To test whether cellular immortalization would reverse these observations, we expressed telomerase in HMECs. In addition to preventing senescence, telomerase expression maintained metabolic flux from glucose into nucleotide synthesis pathways. Finally, we investigated whether inhibition of nucleotide synthesis in proliferating HMECs is sufficient to induce senescence. In proliferating HMECs, both pharmacological and genetic inhibition of ribonucleotide reductase regulatory subunit M2 (RRM2), a rate-limiting enzyme in dNTP synthesis, induced premature senescence with concomitantly decreased metabolic flux from glucose into nucleotide synthesis. Taken together, our results suggest that nucleotide synthesis inhibition plays a causative role in the establishment of replicative senescence in HMECs.


Assuntos
Senescência Celular , Nucleotídeos/metabolismo , Sistemas CRISPR-Cas/genética , Células Cultivadas , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Edição de Genes , Glucose/metabolismo , Humanos , Glândulas Mamárias Humanas/citologia , Metabolômica , Nucleotídeos/análise , Ribonucleosídeo Difosfato Redutase/deficiência , Ribonucleosídeo Difosfato Redutase/genética , Ribonucleosídeo Difosfato Redutase/metabolismo , Telomerase/metabolismo
19.
Sci Rep ; 9(1): 7716, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118434

RESUMO

Conceptus elongation coincides with one of the periods of greatest pregnancy loss in cattle and is characterized by rapid trophectoderm expansion, commencing ~ Day 13 of pregnancy, i.e. before maternal pregnancy recognition. The process has yet to be recapitulated in vitro and does not occur in the absence of uterine gland secretions in vivo. Moreover, conceptus elongation rates are positively correlated to systemic progesterone in maternal circulation. It is, therefore, a maternally-driven and progesterone-correlated developmental phenomenon. This study aimed to comprehensively characterize the biochemical composition of the uterine luminal fluid on Days 12-14 - the elongation-initiation window - in heifers with normal vs. high progesterone, to identify molecules potentially involved in conceptus elongation initiation. Specifically, nucleotide, vitamin, cofactor, xenobiotic, peptide, and energy metabolite profiles of uterine luminal fluid were examined. A total of 59 metabolites were identified, of which 6 and 3 displayed a respective progesterone and day effect, whereas 16 exhibited a day by progesterone interaction, of which 8 were nucleotide metabolites. Corresponding pathway enrichment analysis revealed that pyridoxal, ascorbate, tricarboxylic acid, purine, and pyrimidine metabolism are of likely importance to to conceptus elongation initiation. Moreover, progesterone reduced total metabolite abundance on Day 12 and may alter the uterine microbiome.


Assuntos
Bovinos/fisiologia , Prenhez/fisiologia , Progesterona/fisiologia , Administração Intravaginal , Animais , Blastocisto , Líquidos Corporais/química , Ciclo do Ácido Cítrico , Coenzimas/análise , Metabolismo Energético/efeitos dos fármacos , Feminino , Troca Materno-Fetal , Microbiota/efeitos dos fármacos , Nucleotídeos/análise , Peptídeos/análise , Gravidez , Prenhez/sangue , Progesterona/administração & dosagem , Progesterona/sangue , Útero/efeitos dos fármacos , Útero/metabolismo , Útero/microbiologia , Vitaminas/análise , Xenobióticos/análise
20.
Andrologia ; 51(2): e13191, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30397930

RESUMO

Our previous study found that Chinese chive could significantly (p < 0.01) raise testosterone and nitric oxide (NO) levels in mice serum. However, the specific functional components of this traditional remedy are still unknown. In order to isolate and identify the active constituents from Chinese chive for enhancing testosterone and NO levels, the Chinese chive leaves were extracted by petroleum ether, ethyl acetate, n-butanol and water respectively. Results indicated that the n-butanol extract had a significant effect on NO and testosterone blood levels. Subsequently, n-butanol extract was further isolated by D101 macroporous adsorption and eluted with 50% ethanol and then isolated by Sephadex LH-20 and preparative high-performance liquid chromatography to obtain nucleosides. The fraction eluted with 70% ethanol was further isolated by RP-18 and pre-HPLC to obtain nucleotides. Four novel compounds were identified, and their effects on testosterone and NO levels of male mice were evaluated. Results showed that nucleotides, especially the adenosine in Chinese chive leaves, increased serum testosterone and NO levels in male mice, which had not been reported before. This finding might bring into perspective the treatment strategy for those doctors who treat hormone deficiencies, and might be suitable for using in functional food.


Assuntos
Cebolinha-Francesa/química , Óxido Nítrico/sangue , Nucleosídeos/análise , Nucleotídeos/análise , Extratos Vegetais/química , Folhas de Planta/química , Testosterona/sangue , Animais , Camundongos , Extratos Vegetais/farmacologia
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