PubMed

Use of Ion Chromatography/Mass Spectrometry for Targeted Metabolite Profiling of Polar Organic Acids. Anal Chem. 2016 Oct 26; Authors: Petucci C, Zelenin A, Culver JA, Gabriel M, Kirkbride K, Christison TT, Gardell SJ Abstract Organic acids (OAs) serve as metabolites that play pivotal roles in a host of different metabolic and regulatory pathways. The polar nature of many OAs poses a challenge to their measurement using widely-practiced analytical methods. In this study, a targeted metabolomics method was developed using ion chromatography/triple quadrupole mass spectrometry (IC/MS) to quantitate 28 polar OAs with limits of quantitation ranging from 0.25-50 µM. The inter-day assay precisions ranged from 1-19%, with accuracies ranging from 82 to 115%. The IC/MS assay was used to quantitate OAs in quadriceps muscle from sedentary mice compared to fatigued mice subjected to either a low intensity, long duration (LILD) or high intensity, short duration (HISD) forced treadmill regimen. Among the OAs examined, significant differences were detected for hippuric acid, malic acid, fumaric acid, and 2-ketoglutaric acid between the sedentary and fatigued mice. In conclusion, the IC/MS method enabled the separation and quantitative survey of a broad range of polar OAs that are difficult to analyze by chromatographic techniques. PMID: 27782384 [PubMed - as supplied by publisher]

Detecting beer intake by unique metabolite patterns. J Proteome Res. 2016 Oct 26; Authors: Gürdeniz G, Jensen MG, Meier S, Bech L, Lund E, Dragsted LO Abstract Evaluation of health related effects of beer intake is hampered by the lack of accurate tools for assessing intakes (biomarkers). Therefore, we identified plasma and urine metabolites associated with recent beer intake by untargeted metabolomics and established a characteristic metabolite pattern representing raw materials and beer production as a qualitative biomarker of beer intake. In a randomized, crossover, single-blinded meal study (MSt1) 18 participants were given one at a time four different test beverages: strong, regular and non-alcoholic beers and a soft drink. Four participants were assigned to have two additional beers (MSt2). In addition to plasma and urine samples, test beverages, wort and hops extract were analyzed by UPLC-QTOF. A unique metabolite pattern reflecting beer metabolome, including metabolites derived from beer raw material (i.e. N-methyl tyramine sulfate and the sum of iso-α-acids and tricyclohumols) and production process (i.e. pyro-glutamyl proline and 2-ethyl malate) were selected to establish a compliance biomarker model for detection of beer intake based on MSt1. The model predicted the MSt2 samples collected before and up to 12 h after beer intake correctly (AUC = 1). A biomarker model including four metabolites representing both beer raw materials and production steps provided a specific and accurate tool for measurement of beer consumption. PMID: 27781435 [PubMed - as supplied by publisher]

Related Articles Analysis of Ca(2+) mediated signalling regulating Toxoplasma infectivity reveals complex relationships between key molecules. Cell Microbiol. 2016 Oct 26;: Authors: Stewart RJ, Whitehead L, Nijagal B, Sleebs BE, Lessene G, McConville MJ, Rogers KL, Tonkin CJ Abstract Host cell invasion, exit and parasite dissemination is critical to the pathogenesis of apicomplexan parasites such as Toxoplasma gondii and Plasmodium spp. These processes are regulated by intracellular Ca(2+) signalling although the temporal dynamics of Ca(2+) fluxes and down-stream second messenger pathways are poorly understood. Here we use a genetically encoded biosensor, GFP-Calmodulin-M13-6 (GCaMP6), to capture Ca(2+) flux in live Toxoplasma and investigate the role of Ca(2+) signalling in egress and motility. Our analysis determines how environmental cues and signal activation influence intracellular Ca(2+) flux, allowing placement of effector molecules within this pathway. Importantly, we have identified key interrelationships between cGMP and Ca(2+) signalling that are required for activation of egress and motility. Furthermore, we extend this analysis to show that the Ca(2+) Dependent Protein Kinases - TgCDPK1 and TgCDPK3 - play a role in signal quenching before egress. This work highlights the interrelationships of second messenger pathways of Toxoplasma in space and time, which is likely required for pathogenesis of all apicomplexan species. PMID: 27781359 [PubMed - as supplied by publisher]

Related Articles Effects of 14-day oral low dose selenium nanoparticles and selenite in rat-as determined by metabolite pattern determination. PeerJ. 2016;4:e2601 Authors: Hadrup N, Loeschner K, Skov K, Ravn-Haren G, Larsen EH, Mortensen A, Lam HR, Frandsen HL Abstract Selenium (Se) is an essential element with a small difference between physiological and toxic doses. To provide more effective and safe Se dosing regimens, as compared to dosing with ionic selenium, nanoparticle formulations have been developed. However, due to the nano-formulation, unexpected toxic effects may occur. We used metabolite pattern determination in urine to investigate biological and/or toxic effects in rats administered nanoparticles and for comparison included ionic selenium at an equimolar dose in the form of sodium selenite. Low doses of 10 and 100 fold the recommended human high level were employed to study the effects at borderline toxicity. Evaluations of all significantly changed putative metabolites, showed that Se nanoparticles and sodium selenite induced similar dose dependent changes of the metabolite pattern. Putative identified metabolites included increased decenedioic acid and hydroxydecanedioic acid for both Se formulations whereas dipeptides were only increased for selenite. These effects could reflect altered fatty acid and protein metabolism, respectively. PMID: 27781177 [PubMed - in process]

Related Articles Sucrose Non-Fermenting Related Kinase Enzyme Mediated Rho-Associated Kinase Signaling is Responsible for Cardiac Function. Circ Cardiovasc Genet. 2016 Oct 25;: Authors: Cossette SM, Bhute VJ, Bao X, Harmann LM, Horswill MA, Sinha I, Gastonguay A, Pooya S, Bordas M, Kumar SN, Mirza SP, Palecek S, Strande J, Ramchandran R Abstract BACKGROUND: -Cardiac metabolism is critical for the functioning of the heart, and disturbance in this homeostasis is likely to influence cardiac disorders or cardiomyopathy. Our lab has previously shown that sucrose non-fermenting related kinase (SNRK) enzyme, which belongs to the AMP-activated kinase (AMPK) family, was essential for cardiac metabolism in mammals. Snrk global homozygous knockout (KO) mice die at postnatal day 0, and conditional deletion of Snrk in cardiomyocytes (Snrk cmcKO) leads to cardiac failure, and death by 8-10 months. METHODS AND RESULTS: -We performed additional cardiac functional studies using echocardiography (ECHO), and identified further cardiac functional deficits in Snrk cmcKO mice. NMR-based metabolomics analysis identified key metabolic pathway deficits in SNRK knockdown cardiomyocytes (CMs) in vitro Specifically, metabolites involved in lipid metabolism and oxidative phosphorylation are altered and perturbations in these pathways can result in cardiac function deficits and heart failure. A phosphopeptide-based proteomic screen identified Rho-associated kinase (ROCK) as a putative substrate for SNRK and mass spec-based fragment analysis confirmed key amino acid residues on ROCK that are phosphorylated by SNRK. Western blot analysis on heart lysates from Snrk cmcKO adult mice and SNRK knockdown CMs showed increased ROCK activity. In addition, in vivo inhibition of ROCK partially rescued the in vivo Snrk cmcKO cardiac function deficits. CONCLUSIONS: -Collectively, our data suggests that SNRK in CMs is responsible for maintaining cardiac metabolic homeostasis, which is mediated in part by ROCK and alteration of this homeostasis influences cardiac function in the adult heart. PMID: 27780848 [PubMed - as supplied by publisher]

Related Articles Immunogenic cell death in cancer and infectious disease. Nat Rev Immunol. 2016 Oct 17;: Authors: Galluzzi L, Buqué A, Kepp O, Zitvogel L, Kroemer G Abstract Immunogenicity depends on two key factors: antigenicity and adjuvanticity. The presence of exogenous or mutated antigens explains why infected cells and malignant cells can initiate an adaptive immune response provided that the cells also emit adjuvant signals as a consequence of cellular stress and death. Several infectious pathogens have devised strategies to control cell death and limit the emission of danger signals from dying cells, thereby avoiding immune recognition. Similarly, cancer cells often escape immunosurveillance owing to defects in the molecular machinery that underlies the release of endogenous adjuvants. Here, we review current knowledge on the mechanisms that underlie the activation of immune responses against dying cells and their pathophysiological relevance. PMID: 27748397 [PubMed - as supplied by publisher]

Related Articles Complete metabolome and lipidome analysis reveals novel biomarkers in the human diabetic corneal stroma. Exp Eye Res. 2016 Oct 11;153:90-100 Authors: Priyadarsini S, McKay TB, Sarker-Nag A, Allegood J, Chalfant C, Ma JX, Karamichos D Abstract Prolonged hyperglycemia during diabetes mellitus can cause severe ophthalmic complications affecting both the anterior and posterior ocular segments leading to impaired vision or blindness. Diabetes-induced corneal pathologies are associated with decreased wound healing capacity, corneal edema, and altered epithelial basement membrane. The mechanism by which diabetes modulates structure and function within the corneal stroma are unknown. In our study, we characterized the effects of diabetes on extracellular matrix, lipid transport, and cellular metabolism by defining the entire metabolome and lipidome of Type 1 and Type 2 human diabetic corneal stroma. Significant increases in Collagen I and III were found in diabetic corneas suggesting that diabetes promotes defects in matrix structure leading to scarring. Furthermore, increased lipid content, including sphingosine-1-phosphate and dihydrosphingosine, in diabetic corneas compared to healthy controls were measured suggesting altered lipid retention. Metabolomics analysis identified elevated tryptophan metabolites, independent of glucose metabolism, which correlated with upregulation of the Kynurenine pathway in diabetic corneas. We also found significant upregulation of novel biomarkers aminoadipic acid, D,L-pipecolic acid, and dihydroorotate. Our study links aberrant tryptophan metabolism to end-stage pathologies associated with diabetes indicating the potential of the Kynurenine pathway as a therapeutic target for inhibiting diabetes-associated defects in the eye. PMID: 27742548 [PubMed - as supplied by publisher]

Related Articles Mouse models in oncoimmunology. Nat Rev Cancer. 2016 Sep 30;: Authors: Zitvogel L, Pitt JM, Daillère R, Smyth MJ, Kroemer G Abstract Fundamental cancer research and the development of efficacious antineoplastic treatments both rely on experimental systems in which the relationship between malignant cells and immune cells can be studied. Mouse models of transplantable, carcinogen-induced or genetically engineered malignancies - each with their specific advantages and difficulties - have laid the foundations of oncoimmunology. These models have guided the immunosurveillance theory that postulates that evasion from immune control is an essential feature of cancer, the concept that the long-term effects of conventional cancer treatments mostly rely on the reinstatement of anticancer immune responses and the preclinical development of immunotherapies, including currently approved immune checkpoint blockers. Specific aspects of pharmacological development, as well as attempts to personalize cancer treatments using patient-derived xenografts, require the development of mouse models in which murine genes and cells are replaced with their human equivalents. Such 'humanized' mouse models are being progressively refined to characterize the leukocyte subpopulations that belong to the innate and acquired arms of the immune system as they infiltrate human cancers that are subjected to experimental therapies. We surmise that the ever-advancing refinement of murine preclinical models will accelerate the pace of therapeutic optimization in patients. PMID: 27687979 [PubMed - as supplied by publisher]

17 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2016/10/26PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

26 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2016/10/25PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Oxidative defense metabolites induced by salinity stress in roots of Salicornia herbacea. J Plant Physiol. 2016 Sep 29;206:133-142 Authors: Lee SJ, Jeong EM, Ki AY, Oh KS, Kwon J, Jeong JH, Chung NJ Abstract High salinity is a major abiotic stress that affects the growth and development of plants. This type of stress can influence flowering, the production of crops, defense mechanisms and other physiological processes. Previous studies have attempted to elucidate salt-tolerance mechanisms to improve plant growth and productivity in the presence of sodium chloride. One such plant that has been studied in detail is Salicornia, a well-known halophyte, which has adapted to grow in the presence of high salt. To further the understanding of how Salicornia grows and develops under high saline conditions, Salicornia herbacea (S. herbacea) was grown under varying saline concentrations (0, 50, 100, 200, 300, and 400mM), and the resulting phenotype, ion levels, and metabolites were investigated. The optimal condition for the growth of S. herbacea was determined to be 100mM NaCl, and increased salt concentrations directly decreased the internal concentrations of other inorganic ions including Ca(2+), K(+), and Mg(2+). Metabolomics were performed on the roots of the plant as a systematic metabolomics study has not yet been reported for Salicornia roots. Using ethylacetate and methanol extraction followed by high resolution ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS), 1793 metabolites were identified at different NaCl levels. Structural and functional analyses demonstrated that the concentration of 53 metabolites increased as the concentration of NaCl increased. These metabolites have been linked to stress responses, primarily oxidative stress responses, which increase under saline stress. Most metabolites can be classified as polyols, alkaloids, and steroids. Functional studies of these metabolites show that shikimic acid, vitamin K1, and indole-3-carboxylic acid are generated as a result of defense mechanisms, including the shikimate pathway, to protect against reactive oxygen species (ROS) generated by salt stress. This metabolite profiling provides valuable information on the salt-tolerance mechanisms of S. herbacea and may be applied to bioengineer plants with improved salt tolerance. PMID: 27770750 [PubMed - as supplied by publisher]

Identification of urinary metabolites with potential blood pressure-lowering effects in lentil-fed spontaneously hypertensive rats. Eur J Nutr. 2016 Oct 21; Authors: Hanson M, Zahradka P, Taylor CG, Aliani M Abstract PURPOSE: Urine samples were obtained from a previously completed study that showed lentil consumption attenuates the increase in blood pressure that occurs over time in spontaneously hypertensive rats (SHRs). The objective of the present study was to compare the metabolite profile of the urine samples from control and lentil-fed SHR in relation to the compounds present in lentils but not in other pulses. METHODS: The urine samples were from 17-week-old, male SHR fed semi-purified diet prepared with powder (30 %, w/w) from cooked whole pulses or a pulse-free control diet (n = 8/group) for 4 weeks. Pulse powders, control diet and urine samples were extracted using acetonitrile and analyzed by a high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). RESULTS: Twenty-seven metabolites were significantly different in urine samples from lentil-fed SHR compared to SHR fed control diet, but only 7 were not present in the urine of SHR fed other pulses. Of these metabolites, only citrulline is linked to blood pressure regulation via production of the vasodilator nitric oxide (NO). Several arginine-related compounds that are NO synthase substrates or inhibitors were detected in lentils but not the control diet or other pulse powders. CONCLUSIONS: Consumption of lentils increases the availability of arginine and several related compounds that could potentially elevate production of NO and contribute to the blood pressure-lowering effects of lentil-rich diets. PMID: 27770189 [PubMed - as supplied by publisher]

(1)H nuclear magnetic resonance (NMR)-based serum metabolomics of human gallbladder inflammation. Inflamm Res. 2016 Oct 21; Authors: Sharma RK, Mishra K, Farooqui A, Behari A, Kapoor VK, Sinha N Abstract OBJECTIVE AND DESIGN: We present in this article (1)H nuclear magnetic resonance (NMR)-based metabolic approach to screen the serum metabolic alterations in human gallbladder inflammation with chronic cholecystitis (CC). MATERIAL/METHODS: Total of 71 human serum samples was divided into two groups, (n = 41, CC) and (n = 30 control). (1)H NMR metabolic profiling was carried out for investigation of metabolic alterations. Multivariate statistical analysis was applied for pattern recognition and identification of metabolites playing crucial role in gallbladder inflammation. Receiver operating curve (ROC) and pathway analysis on NMR data were also carried out to validate the findings. RESULTS: Serum metabolites such as glutamine, low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), alanine, branch chained amino acids (BCAA), histidine and tyrosine were found to be depleted whereas formate, lactate, 1,2-propanediol were found to be elevated in CC. Metabolic pathways associated with metabolite alteration have also been reported. CONCLUSIONS: NMR has been established for disease diagnosis along with identification of metabolic pattern recognition in biofluids. Gallstones cause inflammation of the gallbladder in the form of CC. Inflammation plays a major role in causation of gall bladder cancer and leads the way to malignancy. Metabolic analysis of CC may lead to early diagnosis of disease and its progression to gallbladder cancer. PMID: 27770143 [PubMed - as supplied by publisher]

The Microbiome: Modulator of Pharmacological and Toxicological Exposures and Responses. Toxicol Pathol. 2016 Oct 21;: Authors: Silbergeld EK Abstract The microbiome is increasingly recognized as a critical component in human development, health, and disease. Its relevance to toxicology and pharmacology involves challenges to current concepts related to absorption, metabolism, gene:environment, and pathways of response. Framing testable hypotheses for experimental and epidemiological studies will require attention to study designs, biosampling, data analysis, and attention to confounders. PMID: 27770110 [PubMed - as supplied by publisher]

Changes in energy metabolism due to acute rotenone-induced mitochondrial complex I dysfunction - An in vivo large animal model. Mitochondrion. 2016 Oct 18;: Authors: Karlsson M, Ehinger JK, Piel S, Sjövall F, Henriksnäs J, Höglund U, Hansson MJ, Elmér E Abstract Metabolic crisis is a clinical condition primarily affecting patients with inherent mitochondrial dysfunction in situations of augmented demand. To model this, ten pigs received an infusion of rotenone, a mitochondrial complex I inhibitor, or vehicle. Clinical parameters, blood gases, continuous indirect calorimetry, in vivo muscle oxygen tension, ex vivo mitochondrial respiration and metabolomics were assessed. Rotenone induced a progressive increase in lactate which was paralleled by an increase in oxygen tension in venous blood and skeletal muscle. There was an initial decrease in whole body oxygen utilization and mitochondrial respiration in platelets was inhibited. While levels of succinate were decreased, other intermediates of glycolysis and the TCA cycle were increased. This model may be suited for evaluating pharmaceutical interventions aimed at counteracting metabolic changes due to complex I dysfunction. PMID: 27769952 [PubMed - as supplied by publisher]

Biosensor-based spatial and developmental mapping of maize leaf glutamine at vein-level resolution in response to different nitrogen rates and uptake/assimilation durations. BMC Plant Biol. 2016 Oct 21;16(1):230 Authors: Goron TL, Raizada MN Abstract BACKGROUND: The amino acid glutamine (Gln) is a primary transport form of nitrogen in vasculature following root uptake, critical for the location/timing of growth in maize and other cereals. Analytical chemistry methods do not permit in situ analysis of Gln, including visualization within the vascular network. Their cost and tissue requirement are barriers to exploring the complexity of Gln dynamics. We previously reported a biosensor, GlnLux, which can measure relative Gln levels inexpensively with tiny amounts of tissue. RESULTS: Here, maize seedlings were given different N rates for multiple uptake/assimilation durations, after which > 1500 leaf disk extracts were analyzed. A second technique permitted in situ imaging of Gln for all leaves sampled simultaneously. We demonstrate that multifactorial interactions govern Gln accumulation involving position within each leaf (mediolateral/proximodistal), location of leaves along the shoot axis, N rate, and uptake duration. In situ imaging localized Gln in leaf veins for the first time. A novel hypothesis is that leaf Gln may flow along preferential vascular routes, for example in response to mechanical damage or metabolic needs. CONCLUSIONS: The GlnLux technology enabled the most detailed map of relative Gln accumulation in any plant, and the first report of in situ Gln at vein-level resolution. The technology might be used with any plant species in a similar manner. PMID: 27769186 [PubMed - in process]

Related Articles Effect of amino acid supplementation on titer and glycosylation distribution in hybridoma cell cultures-Systems biology-based interpretation using genome-scale metabolic flux balance model and multivariate data analysis. Biotechnol Prog. 2016 Sep;32(5):1163-1173 Authors: Reimonn TM, Park SY, Agarabi CD, Brorson KA, Yoon S Abstract Genome-scale flux balance analysis (FBA) is a powerful systems biology tool to characterize intracellular reaction fluxes during cell cultures. FBA estimates intracellular reaction rates by optimizing an objective function, subject to the constraints of a metabolic model and media uptake/excretion rates. A dynamic extension to FBA, dynamic flux balance analysis (DFBA), can calculate intracellular reaction fluxes as they change during cell cultures. In a previous study by Read et al. (2013), a series of informed amino acid supplementation experiments were performed on twelve parallel murine hybridoma cell cultures, and this data was leveraged for further analysis (Read et al., Biotechnol Prog. 2013;29:745-753). In order to understand the effects of media changes on the model murine hybridoma cell line, a systems biology approach is applied in the current study. Dynamic flux balance analysis was performed using a genome-scale mouse metabolic model, and multivariate data analysis was used for interpretation. The calculated reaction fluxes were examined using partial least squares and partial least squares discriminant analysis. The results indicate media supplementation increases product yield because it raises nutrient levels extending the growth phase, and the increased cell density allows for greater culture performance. At the same time, the directed supplementation does not change the overall metabolism of the cells. This supports the conclusion that product quality, as measured by glycoform assays, remains unchanged because the metabolism remains in a similar state. Additionally, the DFBA shows that metabolic state varies more at the beginning of the culture but less by the middle of the growth phase, possibly due to stress on the cells during inoculation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1163-1173, 2016. PMID: 27452371 [PubMed - in process]

27 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2016/10/22PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

31 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2016/10/21PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

27 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2016/10/19PubMed comprises more than 24 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.