PubMed

Metabolome disruption of the rat cerebrum induced by the acute toxic effects of the synthetic cannabinoid MAM-2201. Life Sci. 2015 May 29; Authors: Zaitsu K, Hayashi Y, Suzuki K, Nakayama H, Hattori N, Takahara R, Kusano M, Tsuchihashi H, Ishi A Abstract AIMS: The aims of this study is to investigate the metabolome disruption in rat cerebrum induced by the recently abused synthetic cannabinoid MAM-2201. MAIN METHODS: MAM-2201 was intraperitoneally administered to 6-week Wistar rats at 5 or 15 mg/kg (n=5), and the cerebrum metabolome alteration was investigated using gas chromatography/tandem mass spectrometry (GC/MS/MS)-based metabolomics technique. KEY FINDINGS AND SIGNIFICANCE: MAM-2201 induced oligopnea and hypokinesia at 5 mg/kg dose, while more abnormal symptoms like rotational and seizure-like behaviors were observed at 15 mg/kg dose, suggesting that MAM-2201 induced neurofunctional disruptions. GC/MS/MS detected 72 metabolites in the rat cerebrum. The cerebrum levels of 12 of these metabolites, including intermediates of the tricarboxylic acid cycle (malic acid and succinic acid) and glutamic acid (Glu), were significantly changed in MAM-2201 administered groups compared to the control groups. The synthetic cannabinoid MAM-2201 can disrupt not only glutamatergic neurotransmission but also energy metabolism in the rat cerebrum. Such disruption may contribute to the abnormal symptoms induced by synthetic cannabinoids. PMID: 26032255 [PubMed - as supplied by publisher]

Metabolomic profiling and genomic analysis of wheat aneuploid lines to identify genes controlling biochemical pathways in mature grain. Plant Biotechnol J. 2015 Jun 1; Authors: Francki MG, Hayton S, Gummer JP, Rawlinson C, Trengove RD Abstract Metabolomics is becoming an increasingly important tool in plant genomics to decipher the function of genes controlling biochemical pathways responsible for trait variation. Although theoretical models can integrate genes and metabolites for trait variation, biological networks require validation using appropriate experimental genetic systems. In this study, we applied an untargeted metabolite analysis to mature grain of wheat homoeologous group 3 ditelosomic lines, selected compounds that showed significant variation between wheat lines Chinese Spring and at least one ditelosomic line, tracked the genes encoding enzymes of their biochemical pathway using the wheat genome survey sequence and determined the genetic components underlying metabolite variation. A total of 412 analytes were resolved in the wheat grain metabolome, and principal component analysis indicated significant differences in metabolite profiles between Chinese Spring and each ditelosomic lines. The grain metabolome identified 55 compounds positively matched against a mass spectral library where the majority showed significant differences between Chinese Spring and at least one ditelosomic line. Trehalose and branched-chain amino acids were selected for detailed investigation, and it was expected that if genes encoding enzymes directly related to their biochemical pathways were located on homoeologous group 3 chromosomes, then corresponding ditelosomic lines would have a significant reduction in metabolites compared with Chinese Spring. Although a proportion showed a reduction, some lines showed significant increases in metabolites, indicating that genes directly and indirectly involved in biosynthetic pathways likely regulate the metabolome. Therefore, this study demonstrated that wheat aneuploid lines are suitable experimental genetic system to validate metabolomics-genomics networks. PMID: 26032167 [PubMed - as supplied by publisher]

LC-MS untargeted metabolomic analysis of drug-induced hepatotoxicity in HepG2 cells. Electrophoresis. 2015 Jun 1; Authors: García-Cañaveras JC, Jiménez N, Gómez-Lechón MJ, Castell JV, Donato MT, Lahoz A Abstract Hepatotoxicity is the number one cause for agencies not approving and withdrawing drugs for the market. Drug-induced human hepatotoxicity frequently goes undetected in pre-clinical safety evaluations using animal models. Human-derived in vitro models represent a common alternative to in vivo tests to detect toxic effects during pre-clinical testing. Most current in vitro toxicity assays rely on the measurement of nonspecific or low sensitive endpoints, which result in poor concordance with human liver toxicity. Therefore, making more accurate predictions of the potential hepatotoxicity of new drugs remains a challenge. Metabolomics, whose aim is to globally assess all the metabolites in a biological sample, may represent an alternative in the search for sensitive sublethal markers of drug-induced hepatotoxicity. To this end, a comprehensive LC-MS-based untargeted metabolite profiling analysis of HepG2 cells, exposed to a set of well-described model hepatotoxins and innocuous compounds, was performed. It allowed to determine meaningful metabolic changes triggered by a toxic insult and gave a first estimation of the main toxicity-related pathways. Based on these metabolic patterns, a PLS-DA model, able to discriminate between nontoxic and hepatotoxic compounds, was constructed. The approach described herein may provide an alternative for animal testing in pre-clinical stages of drug development and a controlled experimental approach to gain a profound understanding of the underlying causes of hepatotoxicity. This article is protected by copyright. All rights reserved. PMID: 26031481 [PubMed - as supplied by publisher]

[Obesity as pathology of adipocytes: number of cells, volume of arterial bloodstream,local pools of circulation in vivo, natriuretic peptides and arterial hypertension]. Klin Lab Diagn. 2015 Mar;60(3):4-13 Authors: Titov VN, Dmitriev VA Abstract The non-specific systemic biological reaction of arterial pressure from the level of organism. vasomotor center and proximal section of arterial bloodstream is appealed to compensate disorders of metabolism and microcirculation in distal section of arteries. This phenomenon occurs in several cases. The primarily local disorders of metabolism at autocrine level, physiological (aphysiological) death of cells, "littering" of intercellular medium become the cause of disorder of microcirculation in paracrin cenosises and deteriorate realization of biological functions of homeostasis, trophology, endoecology and adaptation. The local compensation of affected perfusion in paracrin cenosises at the expense of function of peripheral peristaltic pumps, redistribution of local bloodflow in biological reaction of endothelium-depended vaso-dilation has no possibility to eliminate disorders in realization of biological functions. The systemic increase of arterial pressure under absence of specific symptoms of symptomatic arterial hypertension is a test to detect disorder of biological functions of homeostasis, trophology, biological function of endoecology and adaptation. Allforms of arterial hypertension develop by common algorithm independently from causes of disorders of blood flow, microcirculation in distal section of arteries. The non-specific systemic compensation ofdisorders of metabolism from level of organism, in proximal section of arterial bloodstream always is the same one and results in aphysiological alterations in organs-targets. To comprehend etiological characteristics of common pathogenesis of arterial hypertension is possible in case of application of such technically complicated and still unclear in differential diagnostic of deranged functions modes of metabolomics. PMID: 26031157 [PubMed - in process]

Related Articles Multiple mass isotopomer tracing of acetyl-CoA metabolism in Langendorff-perfused rat hearts: channeling of acetyl-CoA from pyruvate dehydrogenase to carnitine acetyltransferase. J Biol Chem. 2015 Mar 27;290(13):8121-32 Authors: Li Q, Deng S, Ibarra RA, Anderson VE, Brunengraber H, Zhang GF Abstract We developed an isotopic technique to assess mitochondrial acetyl-CoA turnover (≈citric acid flux) in perfused rat hearts. Hearts are perfused with buffer containing tracer [(13)C2,(2)H3]acetate, which forms M5 + M4 + M3 acetyl-CoA. The buffer may also contain one or two labeled substrates, which generate M2 acetyl-CoA (e.g. [(13)C6]glucose or [1,2-(13)C2]palmitate) or/and M1 acetyl-CoA (e.g. [1-(13)C]octanoate). The total acetyl-CoA turnover and the contributions of fuels to acetyl-CoA are calculated from the uptake of the acetate tracer and the mass isotopomer distribution of acetyl-CoA. The method was applied to measurements of acetyl-CoA turnover under different conditions (glucose ± palmitate ± insulin ± dichloroacetate). The data revealed (i) substrate cycling between glycogen and glucose-6-P and between glucose-6-P and triose phosphates, (ii) the release of small excess acetyl groups as acetylcarnitine and ketone bodies, and (iii) the channeling of mitochondrial acetyl-CoA from pyruvate dehydrogenase to carnitine acetyltransferase. Because of this channeling, the labeling of acetylcarnitine and ketone bodies released by the heart are not proxies of the labeling of mitochondrial acetyl-CoA. PMID: 25645937 [PubMed - indexed for MEDLINE]

GC-MS Based Plasma Metabolomics for Identification of Candidate Biomarkers for Hepatocellular Carcinoma in Egyptian Cohort. PLoS One. 2015;10(6):e0127299 Authors: Nezami Ranjbar MR, Luo Y, Di Poto C, Varghese RS, Ferrarini A, Zhang C, Sarhan NI, Soliman H, Tadesse MG, Ziada DH, Roy R, Ressom HW Abstract This study evaluates changes in metabolite levels in hepatocellular carcinoma (HCC) cases vs. patients with liver cirrhosis by analysis of human blood plasma using gas chromatography coupled with mass spectrometry (GC-MS). Untargeted metabolomic analysis of plasma samples from participants recruited in Egypt was performed using two GC-MS platforms: a GC coupled to single quadruple mass spectrometer (GC-qMS) and a GC coupled to a time-of-flight mass spectrometer (GC-TOFMS). Analytes that showed statistically significant changes in ion intensities were selected using ANOVA models. These analytes and other candidates selected from related studies were further evaluated by targeted analysis in plasma samples from the same participants as in the untargeted metabolomic analysis. The targeted analysis was performed using the GC-qMS in selected ion monitoring (SIM) mode. The method confirmed significant changes in the levels of glutamic acid, citric acid, lactic acid, valine, isoleucine, leucine, alpha tocopherol, cholesterol, and sorbose in HCC cases vs. patients with liver cirrhosis. Specifically, our findings indicate up-regulation of metabolites involved in branched-chain amino acid (BCAA) metabolism. Although BCAAs are increasingly used as a treatment for cancer cachexia, others have shown that BCAA supplementation caused significant enhancement of tumor growth via activation of mTOR/AKT pathway, which is consistent with our results that BCAAs are up-regulated in HCC. PMID: 26030804 [PubMed - as supplied by publisher]

Myo-inositol improves the host's ability to eliminate balofloxacin-resistant Escherichia coli. Sci Rep. 2015;5:10720 Authors: Chen XH, Zhang BW, Li H, Peng XX Abstract Antibiotic-resistant mechanisms are associated with fitness costs. However, why antibiotic-resistant bacteria usually show increasing adaptation to hosts is largely unknown, especially from the host's perspective. The present study reveals the host's varied response to balofloxacin-resistant Escherichia coli (BLFX-R) using an integrated proteome and metabolome approach and identifies myo-inositol and phagocytosis-related proteins as crucial biomarkers. Originally, macrophages have an optimal attractive preference to BLFX-S due to more polarization of BLFX-S than BLFX-R, which renders faster elimination to BLFX-S than BLFX-R. The slower elimination to BLFX-R may be reversed by exogenous myo-inositol. Primarily, myo-inositol depolarizes macrophages, elevating adherence to both BLFX-S and BLFX-R. Since the altered adherence is equal to both strains, the myo-inositol-treated macrophages are free of the barrier to BLFX-R and thereby promote phagocytosis of BLFX-R. This work provides a novel strategy based on metabolic modulation for eliminating antibiotic-resistant bacteria with a high degree of host adaptation. PMID: 26030712 [PubMed - as supplied by publisher]

Lactate and energy metabolism during exercise in patients with blocked glycogenolysis (McArdle disease). J Clin Endocrinol Metab. 2015 Jun 1;:jc20151339 Authors: Ørngreen MC, Jeppesen TD, Taivassalo T, Hauerslev S, Preisler N, Heinicke K, Haller RG, Vissing J, van Hall G Abstract CONTEXT: Patients with blocked muscle glycogen breakdown (McArdle disease) have severely reduced exercise capacity compared to healthy individuals and suggested not to produce lactate during exercise. OBJECTIVE: The objectives were to: 1) quantifying systemic and muscle lactate kinetics and oxidation rates and muscle energy utilization during exercise in patients with McArdle disease; 2) elucidate the role of lactate formation in muscle energy production. DESIGN: Single trial Setting: Hospital Participants: Four patients with McArdle disease and seven healthy subjects. INTERVENTION: Patients and healthy controls were studied at rest, followed by 40 min of cycle-ergometer exercise at 60% of the patients maximal oxygen uptake (∼35 W). MAIN OUTCOME MEASURES: Systemic and leg skeletal muscle lactate, alanine, fatty acids and glucose kinetics. RESULTS: McArdle patients had a marked decrease in plasma lactate concentration at the onset of exercise that remained suppressed during exercise. A substantial leg net lactate uptake and subsequent oxidation occurred over the entire exercise period in contrast to a net lactate release or no exchange in the healthy controls. Despite a net lactate uptake by the active leg, a simultaneous unidirectional lactate release was observed in McArdle patients at rates, which were similar to the healthy controls. CONCLUSION: Lactate is an important energy source for contracting skeletal muscle in patients with myophosphorylase deficiency. Although McArdle patients had net leg lactate consumption, a simultaneous release of lactate was observed at rates similar to that found in healthy individuals exercising at the same very low workload, suggesting that lactate formation is mandatory for muscle energy generation during exercise. PMID: 26030324 [PubMed - as supplied by publisher]

Gut Microbiome and Obesity: A Plausible Explanation for Obesity. Curr Obes Rep. 2015 Jun;4(2):250-261 Authors: Sanmiguel C, Gupta A, Mayer EA Abstract Obesity is a multifactorial disorder that results in excessive accumulation of adipose tissue. Although obesity is caused by alterations in the energy consumption/expenditure balance, the factors promoting this disequilibrium are incompletely understood. The rapid development of new technologies and analysis strategies to decode the gut microbiota composition and metabolic pathways has opened a door into the complexity of the guest-host interactions between the gut microbiota and its human host in health and in disease. Pivotal studies have demonstrated that manipulation of the gut microbiota and its metabolic pathways can affect host's adiposity and metabolism. These observations have paved the way for further assessment of the mechanisms underlying these changes. In this review we summarize the current evidence for possible mechanisms underlying gut microbiota induced obesity. The review addresses some well-known effects of the gut microbiota on energy harvesting and changes in metabolic machinery, on metabolic and immune interactions and on possible changes in brain function and behavior. Although there is limited understanding on the symbiotic relationship between us and our gut microbiome, and how disturbances of this relationship affects our health, there is compelling evidence for an important role of the gut microbiota in the development and perpetuation of obesity. PMID: 26029487 [PubMed - as supplied by publisher]

Understanding the foundations of the structural similarities between marketed drugs and endogenous human metabolites. Front Pharmacol. 2015;6:105 Authors: O'Hagan S, Kell DB Abstract BACKGROUND: A recent comparison showed the extensive similarities between the structural properties of metabolites in the reconstructed human metabolic network ("endogenites") and those of successful, marketed drugs ("drugs"). RESULTS: Clustering indicated the related but differential population of chemical space by endogenites and drugs. Differences between the drug-endogenite similarities resulting from various encodings and judged by Tanimoto similarity could be related simply to the fraction of the bitstrings set to 1. By extracting drug/endogenite substructures, we develop a novel family of fingerprints, the Drug Endogenite Substructure (DES) encodings, based on the ranked frequency of the various substructures. These provide a natural assessment of drug-endogenite likeness, and may be used as descriptors with which to derive quantitative structure-activity relationships (QSARs). CONCLUSIONS: "Drug-endogenite likeness" seems to have utility, and leads to a simple, novel and interpretable substructure-based molecular encoding for cheminformatics. PMID: 26029108 [PubMed]

Type I interferons in anticancer immunity. Nat Rev Immunol. 2015 Jun 1; Authors: Zitvogel L, Galluzzi L, Kepp O, Smyth MJ, Kroemer G Abstract Type I interferons (IFNs) are known for their key role in antiviral immune responses. In this Review, we discuss accumulating evidence indicating that type I IFNs produced by malignant cells or tumour-infiltrating dendritic cells also control the autocrine or paracrine circuits that underlie cancer immunosurveillance. Many conventional chemotherapeutics, targeted anticancer agents, immunological adjuvants and oncolytic viruses are only fully efficient in the presence of intact type I IFN signalling. Moreover, the intratumoural expression levels of type I IFNs or of IFN-stimulated genes correlate with favourable disease outcome in several cohorts of patients with cancer. Finally, new anticancer immunotherapies are being developed that are based on recombinant type I IFNs, type I IFN-encoding vectors and type I IFN-expressing cells. PMID: 26027717 [PubMed - as supplied by publisher]

Related Articles Metabolomic analysis of extreme freezing tolerance in Siberian spruce (Picea obovata). New Phytol. 2014 Nov;204(3):545-55 Authors: Angelcheva L, Mishra Y, Antti H, Kjellsen TD, Funk C, Strimbeck RG, Schröder WP Abstract Siberian spruce (Picea obovata) is one of several boreal conifer species that can survive at extremely low temperatures (ELTs). When fully acclimated, its tissues can survive immersion in liquid nitrogen. Relatively little is known about the biochemical and biophysical strategies of ELT survival. We profiled needle metabolites using gas chromatography coupled with mass spectrometry (GC-MS) to explore the metabolic changes that occur during cold acclimation caused by natural temperature fluctuations. In total, 223 metabolites accumulated and 52 were depleted in fully acclimated needles compared with pre-acclimation needles. The metabolite profiles were found to develop in four distinct phases, which are referred to as pre-acclimation, early acclimation, late acclimation and fully acclimated. Metabolite changes associated with carbohydrate and lipid metabolism were observed, including changes associated with increased raffinose family oligosaccharide synthesis and accumulation, accumulation of sugar acids and sugar alcohols, desaturation of fatty acids, and accumulation of digalactosylglycerol. We also observed the accumulation of protein and nonprotein amino acids and polyamines that may act as compatible solutes or cryoprotectants. These results provide new insight into the mechanisms of freezing tolerance development at the metabolite level and highlight their importance in rapid acclimation to ELT in P. obovata. PMID: 25139797 [PubMed - indexed for MEDLINE]

Related Articles The origin of novel avian influenza A (H7N9) and mutation dynamics for its human-to-human transmissible capacity. PLoS One. 2014;9(3):e93094 Authors: Peng J, Yang H, Jiang H, Lin YX, Lu CD, Xu YW, Zeng J Abstract In February 2013, H7N9 (A/H7N9/2013_China), a novel avian influenza virus, broke out in eastern China and caused human death. It is a global priority to discover its origin and the point in time at which it will become transmittable between humans. We present here an interdisciplinary method to track the origin of H7N9 virus in China and to establish an evolutionary dynamics model for its human-to-human transmission via mutations. After comparing influenza viruses from China since 1983, we established an A/H7N9/2013_China virus evolutionary phylogenetic tree and found that the human instances of virus infection were of avian origin and clustered into an independent line. Comparing hemagglutinin (HA) and neuraminidase (NA) gene sequences of A/H7N9/2013_China viruses with all human-to-human, avian, and swine influenza viruses in China in the past 30 years, we found that A/H7N9/2013_China viruses originated from Baer's Pochard H7N1 virus of Hu Nan Province 2010 (HA gene, EPI: 370846, similarity with H7N9 is 95.5%) and duck influenza viruses of Nanchang city 2000 (NA gene, EPI: 387555, similarity with H7N9 is 97%) through genetic re-assortment. HA and NA gene sequence comparison indicated that A/H7N9/2013_China virus was not similar to human-to-human transmittable influenza viruses. To simulate the evolution dynamics required for human-to-human transmission mutations of H7N9 virus, we employed the Markov model. The result of this calculation indicated that the virus would acquire properties for human-to-human transmission in 11.3 years (95% confidence interval (CI): 11.2-11.3, HA gene). PMID: 24671138 [PubMed - indexed for MEDLINE]

Related Articles Evaluation of drug-induced neurotoxicity based on metabolomics, proteomics and electrical activity measurements in complementary CNS in vitro models. Toxicol In Vitro. 2015 May 27; Authors: Schultz L, Zurich MG, Culot M, Costa AF, Landry C, Bellwon P, Kristl T, Hörmann K, Ruzek S, Aiche S, Reinert K, Bielow C, Gosselet F, Cecchelli R, Huber CG, Schroeder OH, Gramowski-Voss A, Weiss DG, Bal-Price A Abstract The present study was performed in an attempt to develop an in vitro integrated testing strategy (ITS) to evaluate drug-induced neurotoxicity. A number of endpoints were analyzed using two complementary brain cell culture models and an in vitro blood-brain barrier (BBB) model after single and repeated exposure treatments with selected drugs that covered the major biological, pharmacological and neuro-toxicological responses. Furthermore, four drugs (diazepam, cyclosporine A, chlorpromazine and amiodarone) were tested more in depth as representatives of different classes of neurotoxicants, inducing toxicity through different pathways of toxicity. The developed in vitro BBB model allowed detection of toxic effects at the level of BBB and evaluation of drug transport through the barrier for predicting free brain concentrations of the studied drugs. The measurement of neuronal electrical activity was found to be a sensitive tool to predict the neuroactivity and neurotoxicity of drugs after acute exposure. The histotypic 3D re-aggregating brain cell cultures, containing all brain cell types, were found to be well suited for OMICs analyses after both acute and long term treatment. The obtained data suggest that an in vitro ITS based on the information obtained from BBB studies and combined with metabolomics, proteomics and neuronal electrical activity measurements performed in stable in vitro neuronal cell culture systems, has high potential to improve current in vitro drug-induced neurotoxicity evaluation. PMID: 26026931 [PubMed - as supplied by publisher]

Related Articles Molecular signature of amniotic fluid derived stem cells in the fetal sheep model of myelomeningocele. J Pediatr Surg. 2015 Apr 28; Authors: Ceccarelli G, Pozzo E, Scorletti F, Benedetti L, Cusella G, Ronzoni FL, Sahakyan V, Zambaiti E, Mimmi MC, Calcaterra V, Deprest J, Sampaolesi M, Pelizzo G Abstract Abnormal cord development results in spinal cord damage responsible for myelomeningocele (MMC). Amniotic fluid-derived stem cells (AFSCs) have emerged as a potential candidate for applications in regenerative medicine. However, their differentiation potential is largely unknown as well as the molecular signaling orchestrating the accurate spinal cord development. Fetal lambs underwent surgical creation of neural tube defect and its subsequent repair. AFSCs were isolated, cultured and characterized at the 12th (induction of MMC), 16th (repair of malformation), and 20th week of gestation (delivery). After performing open hysterectomy, AF collections on fetuses with sham procedures at the same time points as the MMC creation group have been used as controls. Cytological analyses with the colony forming unit assay, XTT and alkaline-phosphatase staining, qRT-PCR gene expression analyses (normalized with aged match controls) and NMR metabolomics profiling were performed. Here we show for the first time the metabolomics and molecular signature variation in AFSCs isolated in the sheep model of MMC, which may be used as diagnostic tools for the in utero identification of the neural tube damage. Intriguingly, PAX3 gene involved in the murine model for spina bifida is modulated in AFSCs reaching the peak of expression at 16weeks of gestation, 4weeks after the intervention. Our data strongly suggest that AFSCs reorganize their differentiation commitment in order to generate PAX3-expressing progenitors to counteract the MMC induced in the sheep model. The gene expression signature of AFSCs highlights the plasticity of these cells reflecting possible alterations of embryonic development. PMID: 26026346 [PubMed - as supplied by publisher]

Related Articles Targeted arginine metabolomics: A rapid, simple UPLC-QToF-MS(E) based approach for assessing the involvement of arginine metabolism in human disease. Clin Chim Acta. 2015 May 27; Authors: Van Dyk M, Mangoni AA, McEvoy M, Attia JR, Sorich MJ, Rowland A Abstract BACKGROUND: Nitric oxide synthase (NOS) mediated conversion of arginine (ARG) to citrulline (CIT) is a key pathway for nitric oxide synthesis. ARG is also metabolised by alternate pathways to ornithine (ORN), homoarginine (HMA), N(G)-monomethyl-L-arginine (MMA), N(G),N(G)-dimethyl-L-arginine (ADMA) and N(G),N(G)'-dimethyl-L-arginine (SDMA), all of which have the capacity to alter NOS activity. Simultaneous assessment of these analytes, when assessing the impact of arginine metabolism in human disease states, is desirable. METHODS: Analytes (ARG, ADMA, SDMA, MMA, HMA, CIT and ORN) were isolated from human plasma by solvent extraction, evaporated and reconstituted. Ultra-performance liquid chromatography (UPLC) was performed on a 150mm x 2.1mm T3 HSS column using a gradient mobile phase comprising ammonium formate (10mM, pH 3.8) in methanol (1% to 63%). Analytes were detected by time-of-flight mass spectrometry (Q-ToF-MS) in positive ion mode with electrospray ionization (ESI+). Data were collected using MS(E). RESULTS: Solvent extraction provided high recovery (>95%). UPLC-QToF-MS(E) facilitated the separation and quantification of the 7 analytes in an analysis time of 6min. The approach has high sensitivity; LOQ range from 0.005μM (NMMA) to 0.25μM (ARG and ORN), and good precision; intra- and inter-day %RSD <6% for all analytes. CONCLUSIONS: This approach provides the capacity to quantify 7 key compounds involved in ARG metabolism in a small sample volume, with a short total analysis time. These characteristics make this approach ideal for undertaking a comprehensive characterisation of this pathway in large data sets (e.g. population studies). PMID: 26026257 [PubMed - as supplied by publisher]

Related Articles Profiling a gut microbiota-generated catechin metabolite's fate in human blood cells using a metabolomic approach. J Pharm Biomed Anal. 2015 May 8;114:71-81 Authors: Mülek M, Fekete A, Wiest J, Holzgrabe U, Mueller MJ, Högger P Abstract The microbial catechin metabolite δ-(3,4-dihydroxy-phenyl)-γ-valerolactone (M1) has been found in human plasma samples after intake of maritime pine bark extract (Pycnogenol(®)). M1 has been previously shown to accumulate in endothelial and blood cells in vitro after facilitated uptake and to exhibit anti-inflammatory activity. The purpose of the present research approach was to systematically and comprehensively analyze the metabolism of M1 in human blood cells in vitro and in vivo. A metabolomic approach that had been successfully applied for drug metabolite profiling was chosen to detect 19 metabolite peaks of M1 which were subsequently further analyzed and validated. The metabolites were categorized into three levels of identification according to the Metabolomics Standards Initiative with six compounds each confirmed at levels 1 and 2 and seven putative metabolites at level 3. The predominant metabolites were glutathione conjugates which were rapidly formed and revealed prolonged presence within the cells. Although a formation of an intracellular conjugate of M1 and glutathione (M1-GSH) was already known two GSH conjugate isomers, M1-S-GSH and M1-N-GSH were observed in the current study. Additionally detected organosulfur metabolites were conjugates with oxidized glutathione and cysteine. Other biotransformation products constituted the open-chained ester form of M1 and a methylated M1. Six of the metabolites determined in in vitro assays were also detected in blood cells in vivo after ingestion of the pine bark extract by two volunteers. The present study provides the first evidence that multiple and structurally heterogeneous polyphenol metabolites can be generated in human blood cells. The bioactivity of the M1 metabolites and their contribution to the previously determined anti-inflammatory effects of M1 now need to be elucidated. PMID: 26025814 [PubMed - as supplied by publisher]

Related Articles Use of the Microbiome in the Practice of Epidemiology: A Primer on -Omic Technologies. Am J Epidemiol. 2015 May 29; Authors: Foxman B, Martin ET Abstract The term microbiome refers to the collective genome of the microbes living in and on our bodies, but it has colloquially come to mean the bacteria, viruses, archaea, and fungi that make up the microbiota (previously known as microflora). We can identify the microbes present in the human body (membership) and their relative abundance using genomics, characterize their genetic potential (or gene pool) using metagenomics, and describe their ongoing functions using transcriptomics, proteomics, and metabolomics. Epidemiologists can make a major contribution to this emerging field by performing well-designed, well-conducted, and appropriately powered studies and by including measures of microbiota in current and future cohort studies to characterize natural variation in microbiota composition and function, identify important confounders and effect modifiers, and generate and test hypotheses about the role of microbiota in health and disease. In this review, we provide an overview of the rapidly growing literature on the microbiome, describe which aspects of the microbiome can be measured and how, and discuss the challenges of including the microbiome as either an exposure or an outcome in epidemiologic studies. PMID: 26025238 [PubMed - as supplied by publisher]

Related Articles Untargeted metabolomics analysis revealed changes in the composition of glycerolipids and phospholipids in Bacillus subtilis under 1-butanol stress. Appl Microbiol Biotechnol. 2015 May 30; Authors: Vinayavekhin N, Mahipant G, Vangnai AS, Sangvanich P Abstract 1-Butanol has been utilized widely in industry and can be produced or transformed by microbes. However, current knowledge about the mechanisms of 1-butanol tolerance in bacteria remains quite limited. Here, we applied untargeted metabolomics to study Bacillus subtilis cells under 1-butanol stress and identified 55 and 37 ions with significantly increased and decreased levels, respectively. Using accurate mass determination, tandem mass spectra, and synthetic standards, 86 % of these ions were characterized. The levels of phosphatidylethanolamine, diglucosyldiacylglycerol, and phosphatidylserine were found to be upregulated upon 1-butanol treatment, whereas those of diacylglycerol and lysyl phosphatidylglycerol were downregulated. Most lipids contained 15:0/15:0, 16:0/15:0, and 17:0/15:0 acyl chains, and all were mapped to membrane lipid biosynthetic pathways. Subsequent two-stage quantitative real-time reverse transcriptase PCR analyses of genes in the two principal membrane lipid biosynthesis pathways revealed elevated levels of ywiE transcripts in the presence of 1-butanol and reduced expression levels of cdsA, pgsA, mprF, clsA, and yfnI transcripts. Thus, the gene transcript levels showed agreement with the metabolomics data. Lastly, the cell morphology was investigated by scanning electron microscopy, which indicated that cells became almost twofold longer after 1.4 % (v/v) 1-butanol stress for 12 h. Overall, the studies uncovered changes in the composition of glycerolipids and phospholipids in B. subtilis under 1-butanol stress, emphasizing the power of untargeted metabolomics in the discovery of new biological insights. PMID: 26025016 [PubMed - as supplied by publisher]

Related Articles Analysis of Eisenia fetida earthworm responses to sub-lethal C60 nanoparticle exposure using (1)H-NMR based metabolomics. Ecotoxicol Environ Saf. 2015 May 26;120:48-58 Authors: Lankadurai BP, Nagato EG, Simpson AJ, Simpson MJ Abstract The enhanced production and environmental release of Buckminsterfullerene (C60) nanoparticles will likely increase the exposure and risk to soil dwelling organisms. We used (1)H NMR-based metabolomics to investigate the response of Eisenia fetida earthworms to sub-lethal C60 nanoparticle exposure in both contact and soil tests. Principal component analysis of (1)H NMR data showed clear separation between controls and exposed earthworms after just 2 days of exposure, however as exposure time increased the separation decreased in soil but increased in contact tests suggesting potential adaptation during soil exposure. The amino acids leucine, valine, isoleucine and phenylalanine, the nucleoside inosine, and the sugars glucose and maltose emerged as potential bioindicators of exposure to C60 nanoparticles. The significant responses observed in earthworms using NMR-based metabolomics after exposure to very low concentrations of C60 nanoparticles suggests the need for further investigations to better understand and predict their sub-lethal toxicity. PMID: 26024814 [PubMed - as supplied by publisher]