PubMed

Review on proteomics for food authentication. J Proteomics. 2016 Jul 4; Authors: Ortea I, O'Connor G, Maquet A Abstract Consumers have the right to know what is in the food they are eating. Accordingly, European and global food regulations require that the provenance of the food can be guaranteed from farm to fork. Many different instrumental techniques have been proposed for food authentication. Although traditional methods are still being used, new approaches such as genomics, proteomics, and metabolomics are helping to complement existing methodologies for verifying the claims made about certain food products. During the last decade, proteomics (the large-scale analysis of proteins in a particular biological system at a particular time) has been applied to different research areas within food technology. Since proteins can be used as markers for many properties of a food, even indicating processes to which the food has been subjected, they can provide further evidence of the foods labeling claim. This review is a comprehensive and updated overview of the applications, drawbacks, advantages, and challenges of proteomics for food authentication in the assessment of the foods compliance with labeling regulations and policies. SIGNIFICANCE: This review paper provides a comprehensive and critical overview of the application of proteomics approaches to determine the authenticity of several food products updating the performances and current limitations of the applied techniques in both laboratory and industrial environments. PMID: 27389853 [PubMed - as supplied by publisher]

Untargeted Metabolomics of Tomato Plants after Root-knot Nematode Infestation. J Agric Food Chem. 2016 Jul 7; Authors: Eloh K, Sasanelli N, Maxia A, Caboni P Abstract After two months from the infestation of tomato plants with the root-knot nematode (RKN) Meloidogyne incognita, we performed a GC-MS untargeted fingerprint analysis for the identification of characteristic metabolites and biomarkers. Principal component analysis (PCA), and orthogonal partial least squares-discriminant analysis (OPLS-DA) suggested dramatic local changes of the plant metabolome. In the case of tomato leaves, β-alanine, phenylalanine, melibiose were induced in response to root-knot nematode stimuli, while ribose, glycerol, myristic acid and palmitic acid were reduced. For tomato stems, upregulated metabolites were: ribose, sucrose, fructose, and glucose while fumaric acid and glycine were downregulated. The variation in molecular strategies to the infestation of root-knot nematodes may play an important role in how Solanum lycopersicum and other plants adapt to nematode parasitic stress. PMID: 27389052 [PubMed - as supplied by publisher]

The metabolic signature of biomass formation in barley. Plant Cell Physiol. 2016 Jul 7; Authors: Ghaffari MR, Shahinnia F, Usadel B, Junker B, Schreiber F, Sreenivasulu N, Hajirezaei MR Abstract The network analysis of genome wide transcriptome responses, metabolic signatures and enzymes' relationship to biomass formation has been studied in a diverse panel of 12 barley accessions during vegetative and reproductive stages. The primary metabolites and enzymes involved in central metabolism that determine the accumulation of shoot biomass at the vegetative stage of barley development are primarily being linked to sucrose accumulation and sucrose synthase activity. Interestingly, the metabolic and enzyme links which are strongly associated with biomass accumulation during reproductive stages are related to the starch accumulation and TCA cycle intermediates citrate, malate, trans-aconitate and isocitrate. Additional significant associations were also found for UDP glucose, adenosine triphosphate and the amino acids isoleucine, valine, glutamate and histidine during the reproductive stage. A network analysis resulted in a combined identification of metabolite and enzyme signatures indicative for grain weight accumulation that was correlated with AGPase activity, a rate limiting enzyme involved in starch biosynthesis and with alanine amino transferase activity involved in the synthesis of storage proteins. We propose that the mechanism related to vegetative and reproductive biomass formation versus seed biomass formation is being linked to distinct fluxes regulating sucrose, starch, sugars and amino acids as central resources. These distinct biomarkers can be used to engineer biomass production and grain weight in barley. PMID: 27388338 [PubMed - as supplied by publisher]

Related Articles Site-Specific Protein N- and O-Glycosylation Analysis by a C18-Porous Graphitized Carbon-Liquid Chromatography-Electrospray Ionization Mass Spectrometry Approach Using Pronase Treated Glycopeptides. Anal Chem. 2015 Dec 1;87(23):11691-9 Authors: Stavenhagen K, Plomp R, Wuhrer M Abstract The analysis of N- and O-glycopeptides remains challenging due to the microheterogeneity (different glycoforms attached to one glycosylation site) and macroheterogeneity (site occupancy) of the glycoprotein. Trypsin is by far the most commonly used protease in glycoproteomic studies; however, it often results in long peptides that can harbor more than one glycan which may hamper site identification. The use of unspecific proteases such as Pronase can largely overcome this problem by generating glycopeptides with a small peptide portion. While the resulting glycopeptides are very useful for tandem mass spectrometric investigation, the analysis with conventional 1D-LC-ESI-MS/MS approaches can lead to incomplete glycosylation coverage because of the very heterogeneous physicochemical properties of the glycopeptides depending on the peptide sequence as well as the size and charges of the glycan moiety. Here, we describe a universal workflow for site-specific N- and O-glycopeptide analysis of Pronase treated glycoproteins with integrated, sequential C18 reverse phase and porous graphitized carbon-LC-ESI-QTOF-MS/MS employing a combination of lower- and enhanced-energy collision-induced dissociation. The approach was evaluated on glycoprotein standards and also applied to investigate the glycosylation of human IgG3 providing details on the hitherto uncharacterized glycosylation site Asn392 of the CH3 domain. This analytical tool can be applied to a variety of glycoproteins for site-specific N- and O-glycopeptide analysis, resulting in a good glycopeptide coverage within a single sample run and, thus, requiring only small amounts of sample. PMID: 26536155 [PubMed - indexed for MEDLINE]

Related Articles Plasma N-Glycome Signature of Down Syndrome. J Proteome Res. 2015 Oct 2;14(10):4232-45 Authors: Borelli V, Vanhooren V, Lonardi E, Reiding KR, Capri M, Libert C, Garagnani P, Salvioli S, Franceschi C, Wuhrer M Abstract In recent years, plasma N-glycans have emerged as biomarkers for health and disease. Here, we studied N-glycomic changes in Down Syndrome (DS). Because of the progeroid phenotype of DS, we focused on the dissection of syndrome- and aging-associated glycomic changes, as well as the interaction thereof. We analyzed the plasma N-glycome of 76 DS persons, 37 siblings (DSS), and 42 mothers (DSM) of DS persons by DNA-sequencer-aided, fluorophore-assisted-carbohydrate-electrophoresis, as well as by matrix-assisted laser desorption ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). The results showed an overall decrease of galactosylation and α2,3 sialylation, a concomitant increase of the level of fucosylated N-glycans as well as of monogalactosylated diantennary N-glycans in DS, while the GlycoAgeTest and the ratio of the two core-fucosylated, monogalactosylated diantennary isomers (galactose positioned on α1,6 arm versus α1,3 arm) were the strongest DS discriminators. Hypogalactosylation is a characteristic of both DS and aging of control individuals. A decrease in α2,3-sialylated species is also common to DS and aging of controls. However, regarding to α2,6-sialylated tri- and tetragalactosylated N-glycan species, we found those to be lowered in DS but showed an increase with age in the same persons, while these glycans were not affected by aging in control individuals. In conclusion, we identified specific glycomic changes associated with DS, aging in DS, as well as aging in controls, identifying glycomic features in line with accelerated aging in DS. Notably, our data demonstrate an aging phenotype in DS which only in part overlaps with aging in controls but reveals DS-specificity. PMID: 26334954 [PubMed - indexed for MEDLINE]

Related Articles Quantitative targeted and retrospective data analysis of relevant pesticides, antibiotics and mycotoxins in bakery products by liquid chromatography-single-stage Orbitrap mass spectrometry. Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2015;32(10):1617-27 Authors: De Dominicis E, Commissati I, Gritti E, Catellani D, Suman M Abstract In addition to 'traditional' multi-residue and multi-contaminant multiple reaction monitoring (MRM) mass spectrometric techniques devoted to quantifying a list of targeted compounds, the global food industry requires non-targeted methods capable of detecting other possible potentially hazardous compounds. Ultra-high-performance liquid chromatography combined with a single-stage Orbitrap high-resolution mass spectrometer (UHPLC-HRMS Exactive™-Orbitrap Technology) was successfully exploited for the complete selective and quantitative determination of 33 target compounds within three major cross categories (pesticides, antibiotics and mycotoxins) in bakery matrices (specifically milk, wheat flour and mini-cakes). Resolution was set at 50 000 full width at half maximum (FWHM) to achieve the right compromise between an adequate scan speed and selectivity, allowing for the limitations related to the necessary generic sample preparation approach. An exact mass with tolerance of 5 ppm and minimum peak threshold of 10 000 units were fixed as the main identification conditions, including retention time and isotopic pattern as additional criteria devoted to greatly reducing the risk of false-positive findings. The full validation for all the target analytes was performed: linearity, intermediate repeatability and recovery (28 analytes within 70-120%) were positively assessed; furthermore, limits of quantification between 5 and 100 µg kg(-1) (with most of the analytes having a limit of detection below 6 µg kg(-1)) indicate good performance, which is compatible with almost all the regulatory needs. Naturally contaminated and fortified mini-cakes, prepared through combined use of industrial and pilot plant production lines, were analysed at two different concentration levels, obtaining good overall quantitative results and providing preliminary indications of the potential of full-scan HRMS cluster analysis. The effectiveness of this analytical approach was also tested in terms of the formulation of hypotheses for the identification of other analytes not initially targeted which can have toxicological implications (e.g. 3-acetyl-deoxynivalenol and deoxynivalenol-3-glucoside), opening a window on retrospective investigation perspectives in food safety laboratories. PMID: 26212769 [PubMed - indexed for MEDLINE]

Citrate Accumulation-Related Gene Expression and/or Enzyme Activity Analysis Combined With Metabolomics Provide a Novel Insight for an Orange Mutant. Sci Rep. 2016;6:29343 Authors: Guo LX, Shi CY, Liu X, Ning DY, Jing LF, Yang H, Liu YZ Abstract 'Hong Anliu' (HAL, Citrus sinensis cv. Hong Anliu) is a bud mutant of 'Anliu' (AL), characterized by a comprehensive metabolite alteration, such as lower accumulation of citrate, high accumulation of lycopene and soluble sugars in fruit juice sacs. Due to carboxylic acid metabolism connects other metabolite biosynthesis and/or catabolism networks, we therefore focused analyzing citrate accumulation-related gene expression profiles and/or enzyme activities, along with metabolic fingerprinting between 'HAL' and 'AL'. Compared with 'AL', the transcript levels of citrate biosynthesis- and utilization-related genes and/or the activities of their respective enzymes such as citrate synthase, cytosol aconitase and ATP-citrate lyase were significantly higher in 'HAL'. Nevertheless, the mitochondrial aconitase activity, the gene transcript levels of proton pumps, including vacuolar H(+)-ATPase, vacuolar H(+)-PPase, and the juice sac-predominant p-type proton pump gene (CsPH8) were significantly lower in 'HAL'. These results implied that 'HAL' has higher abilities for citrate biosynthesis and utilization, but lower ability for the citrate uptake into vacuole compared with 'AL'. Combined with the metabolites-analyzing results, a model was then established and suggested that the reduction in proton pump activity is the key factor for the low citrate accumulation and the comprehensive metabolite alterations as well in 'HAL'. PMID: 27385485 [PubMed - as supplied by publisher]

Renal Transporter-Mediated Drug-Drug Interactions: Are They Clinically Relevant? J Clin Pharmacol. 2016 Jul;56 Suppl 7:S73-S81 Authors: Lepist EI, Ray AS Abstract The kidney, through the distinct processes of passive glomerular filtration and active tubular secretion, plays an important role in the elimination of numerous endobiotics (eg, hormones, metabolites), toxins, nutrients, and drugs. Renal transport pathways mediating active tubular secretion and reabsorption in the proximal tubule are complex, involving apical and basolateral transporters acting in concert. Detailed studies of the molecular mechanisms of net active tubular secretion have established the involvement of multiple transporters with overlapping substrate specificity mediating competing secretion and reabsorption pathways. Although drug interactions arising from inhibition of renal transporters are rare relative to other mechanisms, they can involve commonly administered drugs (eg, cimetidine, metformin), may be underappreciated due to muted effects on plasma pharmacokinetics relative to tissue levels, can affect narrow-therapeutic-index medications (eg, antiarrhythmic, oncology medications), and may disproportionately affect sensitive populations where polypharmacy is common (eg, the elderly, diabetics). In particular, there is the potential for larger-magnitude interactions in subjects with reduced glomerular filtration rates due to the increased relative contribution of tubular secretion. The assessment of additional endpoints in drug-drug interaction studies including pharmacodynamics, positron emission tomography imaging, and metabolomics promises to expand our understanding of the clinical relevance of renal drug interactions. PMID: 27385181 [PubMed - as supplied by publisher]

Monoethylhexyl Phthalate Elicits an Inflammatory Response in Adipocytes Characterized by Alterations in Lipid and Cytokine Pathways. Environ Health Perspect. 2016 Jul 6; Authors: Manteiga S, Lee K Abstract BACKGROUND: A growing body of evidence links endocrine disrupting chemicals (EDCs) with obesity-related metabolic diseases. While it has been shown that EDCs can predispose individuals towards adiposity by affecting developmental processes, little is known about the chemicals' effects on adult adipose tissue. OBJECTIVES: Our aim was to study the effects of low, physiologically relevant doses of EDCs on differentiated murine adipocytes. METHODS: We combined metabolomics, proteomics, and gene expression analysis to characterize the effects of mono-ethylhexyl phthalate (MEHP) in differentiated adipocytes. RESULTS: Repeated exposure to MEHP over several days led to changes in metabolite and enzyme levels indicating elevated lipogenesis and lipid oxidation. The chemical exposure also increased expression of major inflammatory cytokines, including chemotactic factors. Proteomic and gene expression analysis revealed significant alterations in pathways regulated by peroxisome proliferator activated receptor-γ (PPAR-γ). Inhibiting the nuclear receptor's activity using a chemical antagonist abrogated not only the alterations in PPAR-γ regulated metabolic pathways, but also the increases in cytokine expression. CONCLUSIONS: Our results show that MEHP can induce a pro-inflammatory state in differentiated adipocytes. This effect is at least partially mediated PPAR-γ. PMID: 27384973 [PubMed - as supplied by publisher]

Metabolomics of the Antipyretic Effects of Bubali Cornu (Water Buffalo Horn) in Rats. PLoS One. 2016;11(7):e0158478 Authors: Liu R, Huang Q, Shan J, Duan JA, Zhu Z, Liu P, Bian Y, Shang EX, Qian D Abstract Bubali Cornu (water buffalo horn, WBH) has been used for thousands of years in traditional Chinese medicine (TCM) as an effective treatment for heat. In the present study, we have carried out a metabolomics profiling study on plasma and urine samples to explore potential biomarkers and determine how WBH exerts its antipyretic effects in yeast-induced pyrexia at a metabolomic level. Ultra-high performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS), together with multivariate statistical analysis, was used to detect and identify potential biomarkers associated with pyrexia and with WBH treatment. In total, sixteen endogenous metabolites were identified in plasma samples and twenty-one metabolites were detected in urine samples. The biomarkers identified in this study, using metabolic pathway analysis (MetPA), are involved in glycerophospholipid, arachidonic acid, amino acid, sphingolipid, and purine metabolism, all of which are disturbed in rats with pyrexia. As a result, WBH affect arachidonic acid metabolism and oxidative stress in yeast-induced pyrexia rats chiefly. The present study determines the important substances underlying the antipyretic efficacy of WBH at a metabolic level. It might pave the way for further investigations into the mechanisms of action of other animal horn-derived traditional Chinese medicines (TCMs). PMID: 27384078 [PubMed - as supplied by publisher]

Microbiome-wide association studies link dynamic microbial consortia to disease. Nature. 2016;535(7610):94-103 Authors: Gilbert JA, Quinn RA, Debelius J, Xu ZZ, Morton J, Garg N, Jansson JK, Dorrestein PC, Knight R Abstract Rapid advances in DNA sequencing, metabolomics, proteomics and computational tools are dramatically increasing access to the microbiome and identification of its links with disease. In particular, time-series studies and multiple molecular perspectives are facilitating microbiome-wide association studies, which are analogous to genome-wide association studies. Early findings point to actionable outcomes of microbiome-wide association studies, although their clinical application has yet to be approved. An appreciation of the complexity of interactions among the microbiome and the host's diet, chemistry and health, as well as determining the frequency of observations that are needed to capture and integrate this dynamic interface, is paramount for developing precision diagnostics and therapies that are based on the microbiome. PMID: 27383984 [PubMed - as supplied by publisher]

Alterations of the Lipid Metabolome in Dairy Cows Experiencing Excessive Lipolysis Early Postpartum. PLoS One. 2016;11(7):e0158633 Authors: Humer E, Khol-Parisini A, Metzler-Zebeli BU, Gruber L, Zebeli Q Abstract A decrease in insulin sensitivity enhances adipose tissue lipolysis helping early lactation cows counteracting their energy deficit. However, excessive lipolysis poses serious health risks for cows, and its underlying mechanisms are not clearly understood. The present study used targeted ESI-LC-MS/MS-based metabolomics and indirect insulin sensitivity measurements to evaluate metabolic alterations in the serum of dairy cows of various parities experiencing variable lipolysis early postpartum. Thirty (12 primiparous and 18 multiparous) cows of Holstein Friesian and Simmental breeds, fed the same diet and kept under the same management conditions, were sampled at d 21 postpartum and classified as low (n = 10), medium (n = 8), and high (n = 12) lipolysis groups, based on serum concentration of nonesterified fatty acids. Overall, excessive lipolysis in the high group came along with impaired estimated insulin sensitivity and characteristic shifts in acylcarnitine, sphingomyelin, phosphatidylcholine and lysophospholipid metabolome profiles compared to the low group. From the detected phosphatidylcholines mainly those with diacyl-residues showed differences among lipolysis groups. Furthermore, more than half of the detected sphingomyelins were increased in cows experiencing high lipomobilization. Additionally, strong differences in serum acylcarnitines were noticed among lipolysis groups. The study suggests an altered serum phospholipidome in dairy cows associated with an increase in certain long-chain sphingomyelins and the progression of disturbed insulin function. In conclusion, the present study revealed 37 key metabolites as part of alterations in the synthesis or breakdown of sphingolipids and phospholipids associated with lowered estimated insulin sensitivity and excessive lipolysis in early-lactating cows. PMID: 27383746 [PubMed - as supplied by publisher]

Effect of the environment on the secondary metabolic profile of Tithonia diversifolia: a model for environmental metabolomics of plants. Sci Rep. 2016;6:29265 Authors: Sampaio BL, Edrada-Ebel R, Da Costa FB Abstract Tithonia diversifolia is an invasive weed commonly found in tropical ecosystems. In this work, we investigate the influence of different abiotic environmental factors on the plant's metabolite profile by multivariate statistical analyses of spectral data deduced by UHPLC-DAD-ESI-HRMS and NMR methods. Different plant part samples of T. diversifolia which included leaves, stems, roots, and inflorescences were collected from two Brazilian states throughout a 24-month period, along with the corresponding monthly environmental data. A metabolomic approach employing concatenated LC-MS and NMR data was utilised for the first time to study the relationships between environment and plant metabolism. A seasonal pattern was observed for the occurrence of metabolites that included sugars, sesquiterpenes lactones and phenolics in the leaf and stem parts, which can be correlated to the amount of rainfall and changes in temperature. The distribution of the metabolites in the inflorescence and root parts were mainly affected by variation of some soil nutrients such as Ca, Mg, P, K and Cu. We highlight the environment-metabolism relationship for T. diversifolia and the combined analytical approach to obtain reliable data that contributed to a holistic understanding of the influence of abiotic environmental factors on the production of metabolites in various plant parts. PMID: 27383265 [PubMed - as supplied by publisher]

Spherulization as a process for the exudation of chemical cues by the encrusting sponge C. crambe. Sci Rep. 2016;6:29474 Authors: Ternon E, Zarate L, Chenesseau S, Croué J, Dumollard R, Suzuki MT, Thomas OP Abstract Ecological interactions in the marine environment are now recognized to be partly held by chemical cues produced by marine organisms. In particular, sponges are sessile animals thought to rely on the bioactive substances they synthesize to ensure their development and defense. However, the mechanisms leading the sponges to use their specialized metabolites as chemical cues remain unknown. Here we report the constant release of bioactive polycyclic guanidinic alkaloids by the Mediterranean sponge Crambe crambe into the dissolved and the particulate phases using a targeted metabolomics study. These compounds were proven to be stored into already described specialized (spherulous) sponge cells and dispersed into the water column after release through the sponge exhaling channels (oscula), leading to a chemical shield surrounding the sponge. Low concentrations of these compounds were demonstrated to have teratogenic effects on embryos of a common sea squirt (ascidian). This mechanism of action called spherulization may therefore contribute to the ecological success of encrusting sponges that need to extend their substrate cover to expand. PMID: 27381941 [PubMed - as supplied by publisher]

A Genetic Response Score for Hydrochlorothiazide Use: Insights From Genomics and Metabolomics Integration. Hypertension. 2016 Jul 5; Authors: Shahin MH, Gong Y, McDonough CW, Rotroff DM, Beitelshees AL, Garrett TJ, Gums JG, Motsinger-Reif A, Chapman AB, Turner ST, Boerwinkle E, Frye RF, Fiehn O, Cooper-DeHoff RM, Kaddurah-Daouk R, Johnson JA Abstract Hydrochlorothiazide is among the most commonly prescribed antihypertensives; yet, <50% of hydrochlorothiazide-treated patients achieve blood pressure (BP) control. Herein, we integrated metabolomic and genomic profiles of hydrochlorothiazide-treated patients to identify novel genetic markers associated with hydrochlorothiazide BP response. The primary analysis included 228 white hypertensives treated with hydrochlorothiazide from the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) study. Genome-wide analysis was conducted using Illumina Omni 1 mol/L-Quad Chip, and untargeted metabolomics was performed on baseline fasting plasma samples using a gas chromatography-time-of-flight mass spectrometry platform. We found 13 metabolites significantly associated with hydrochlorothiazide systolic BP (SBP) and diastolic BP (DBP) responses (false discovery rate, <0.05). In addition, integrating genomic and metabolomic data revealed 3 polymorphisms (rs2727563 PRKAG2, rs12604940 DCC, and rs13262930 EPHX2) along with arachidonic acid, converging in the netrin signaling pathway (P=1×10(-5)), as potential markers, significantly influencing hydrochlorothiazide BP response. We successfully replicated the 3 genetic signals in 212 white hypertensives treated with hydrochlorothiazide and created a response score by summing their BP-lowering alleles. We found patients carrying 1 response allele had a significantly lower response than carriers of 6 alleles (ΔSBP/ΔDBP: -1.5/1.2 versus -16.3/-10.4 mm Hg, respectively, SBP score, P=1×10(-8) and DBP score, P=3×10(-9)). This score explained 11.3% and 11.9% of the variability in hydrochlorothiazide SBP and DBP responses, respectively, and was further validated in another independent study of 196 whites treated with hydrochlorothiazide (DBP score, P=0.03; SBP score, P=0.07). This study suggests that PRKAG2, DCC, and EPHX2 might be important determinants of hydrochlorothiazide BP response. PMID: 27381900 [PubMed - as supplied by publisher]

Enhanced base excision repair capacity in carotid atherosclerosis may protect nuclear DNA but not mitochondrial DNA. Free Radic Biol Med. 2016 Jul 2; Authors: Skarpengland T, Dahl TB, Skjelland M, Scheffler K, Sousa MM, Gregersen I, Kuśnierczyk A, Sharma A, Slupphaug G, Eide L, Segers FM, Skagen KR, Dahl CP, Russell D, Folkersen L, Krohg-Sørensen K, Holm S, Bjørås M, Aukrust P, Halvorsen B Abstract BACKGROUND: Lesional and systemic oxidative stress has been implicated in the pathogenesis of atherosclerosis, potentially leading to accumulation of DNA base lesions within atherosclerotic plaques. Although base excision repair (BER) is a major pathway counteracting oxidative DNA damage, our knowledge on BER and accumulation of DNA base lesions in clinical atherosclerosis is scarce. Here, we evaluated the transcriptional profile of a wide spectrum of BER components as well as DNA damage accumulation in atherosclerotic and non-atherosclerotic arteries. METHODS: BER gene expression levels were analyzed in 162 carotid plaques, 8 disease-free carotid specimens from patients with carotid plaques and 10 non-atherosclerotic control arteries. Genomic integrity, mitochondrial (mt) DNA copy number, oxidative DNA damage and BER proteins were evaluated in a subgroup of plaques and controls. RESULTS: Our major findings were: (i) The BER pathway showed a global increased transcriptional response in plaques as compared to control arteries, accompanied by increased expression of several BER proteins. (ii) Whereas nuclear DNA stability was maintained within carotid plaques, mtDNA integrity and copy number were decreased. (iii) Within carotid plaques, mRNA levels of several BER genes correlated with macrophage markers. (iv) In vitro, some of the BER genes were highly expressed in the anti-inflammatory and pro-resolving M2 macrophages, showing increased expression upon exposure to modified lipids. CONCLUSIONS: The increased transcriptional response of BER genes in atherosclerosis may contribute to lesional nuclear DNA stability but appears insufficient to maintain mtDNA integrity, potentially influencing mitochondrial function in cells within the atherosclerotic lesion. PMID: 27381496 [PubMed - as supplied by publisher]

Related Articles Evidence of Extrapancreatic Glucagon Secretion in Man. Diabetes. 2016 Mar;65(3):585-97 Authors: Lund A, Bagger JI, Wewer Albrechtsen NJ, Christensen M, Grøndahl M, Hartmann B, Mathiesen ER, Hansen CP, Storkholm JH, van Hall G, Rehfeld JF, Hornburg D, Meissner F, Mann M, Larsen S, Holst JJ, Vilsbøll T, Knop FK Abstract Glucagon is believed to be a pancreas-specific hormone, and hyperglucagonemia has been shown to contribute significantly to the hyperglycemic state of patients with diabetes. This hyperglucagonemia has been thought to arise from α-cell insensitivity to suppressive effects of glucose and insulin combined with reduced insulin secretion. We hypothesized that postabsorptive hyperglucagonemia represents a gut-dependent phenomenon and subjected 10 totally pancreatectomized patients and 10 healthy control subjects to a 75-g oral glucose tolerance test and a corresponding isoglycemic intravenous glucose infusion. We applied novel analytical methods of plasma glucagon (sandwich ELISA and mass spectrometry-based proteomics) and show that 29-amino acid glucagon circulates in patients without a pancreas and that glucose stimulation of the gastrointestinal tract elicits significant hyperglucagonemia in these patients. These findings emphasize the existence of extrapancreatic glucagon (perhaps originating from the gut) in man and suggest that it may play a role in diabetes secondary to total pancreatectomy. PMID: 26672094 [PubMed - indexed for MEDLINE]

Related Articles Metabolic Profiling of Chicken Embryos Exposed to Perfluorooctanoic Acid (PFOA) and Agonists to Peroxisome Proliferator-Activated Receptors. PLoS One. 2015;10(12):e0143780 Authors: Mattsson A, Kärrman A, Pinto R, Brunström B Abstract Untargeted metabolic profiling of body fluids in experimental animals and humans exposed to chemicals may reveal early signs of toxicity and indicate toxicity pathways. Avian embryos develop separately from their mothers, which gives unique possibilities to study effects of chemicals during embryo development with minimal confounding factors from the mother. In this study we explored blood plasma and allantoic fluid from chicken embryos as matrices for revealing metabolic changes caused by exposure to chemicals during embryonic development. Embryos were exposed via egg injection on day 7 to the environmental pollutant perfluorooctanoic acid (PFOA), and effects on the metabolic profile on day 12 were compared with those caused by GW7647 and rosiglitazone, which are selective agonists to peroxisome-proliferator activated receptor α (PPARα) and PPARγ, respectively. Analysis of the metabolite concentrations from allantoic fluid by Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA) showed clear separation between the embryos exposed to GW7647, rosiglitazone, and vehicle control, respectively. In blood plasma only GW7647 caused a significant effect on the metabolic profile. PFOA induced embryo mortality and increased relative liver weight at the highest dose. Sublethal doses of PFOA did not significantly affect the metabolic profile in either matrix, although single metabolites appeared to be altered. Neonatal mortality by PFOA in the mouse has been suggested to be mediated via activation of PPARα. However, we found no similarity in the metabolite profile of chicken embryos exposed to PFOA with those of embryos exposed to PPAR agonists. This indicates that PFOA does not activate PPAR pathways in our model at concentrations in eggs and embryos well above those found in wild birds. The present study suggests that allantoic fluid and plasma from chicken embryos are useful and complementary matrices for exploring effects on the metabolic profile resulting from chemical exposure during embryonic development. PMID: 26624992 [PubMed - indexed for MEDLINE]

Related Articles Symbiosis dependent accumulation of primary metabolites in arbuscule-containing cells. BMC Plant Biol. 2015;15:234 Authors: Gaude N, Bortfeld S, Erban A, Kopka J, Krajinski F Abstract BACKGROUND: The arbuscular mycorrhizal symbiosis is characterized by the presence of different symbiotic structures and stages within a root system. Therefore tools allowing the analysis of molecular changes at a cellular level are required to reveal insight into arbuscular mycorrhizal (AM) symbiosis development and functioning. RESULTS: Here we describe the analysis of metabolite pools in arbuscule-containing cells, which are the site of nutrient transfer between AM fungus and host plant. Laser capture microdissection (LCM) combined with gas chromatography mass spectrometry (GC-EI/TOF-MS) enabled the analysis of primary metabolite levels,which might be of plant or fungal origin, within these cells. CONCLUSIONS: High levels of the amino acids, aspartate, asparagine, glutamate, and glutamine, were observed in arbuscule-containing cells. Elevated amounts of sucrose and the steady-state of hexose levels indicated a direct assimilation of monosaccharides by the fungal partner. PMID: 26424710 [PubMed - indexed for MEDLINE]

Related Articles LC/MS-based polar metabolite profiling reveals gender differences in serum from patients with myocardial infarction. J Pharm Biomed Anal. 2015 Nov 10;115:475-86 Authors: Lee J, Jung Y, Park JY, Lee SH, Ryu do H, Hwang GS Abstract Myocardial infarction (MI), a leading cause of death worldwide, results from prolonged myocardial ischemia with necrosis of myocytes due to a blood supply obstruction to an area of the heart. Many studies have reported gender-related differences in the clinical features of MI, but the reasons for these differences remain unclear. In this study, we applied ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) and various statistical methods-such as multivariate, pathway, and correlation analyses-to identify gender-specific metabolic patterns in polar metabolites in serum from healthy individuals and patients with MI. Patients with diagnosed MI (n=68), and age- and body mass index-matched healthy individuals (n=68), were included in this study. The partial least-squares discriminant analysis (PLS-DA) model was generated from metabolic profiling data, and the score plots showed a significant gender-related difference in patients with MI. Many pathways were associated with amino acids and purines; amino acids, acylcarnitines, and purines differed significantly between male and female patients with MI. This approach could be utilized to observe gender-specific metabolic pattern differences between healthy controls and patients with MI. PMID: 26299524 [PubMed - indexed for MEDLINE]