PubMed

Recommendations and Standardization of Biomarker Quantification Using NMR-based Metabolomics with Particular Focus on Urinary Analysis. J Proteome Res. 2016 Jan 8; Authors: Emwas AH, Roy R, McKay RT, Ryan D, Brennan L, Tenori L, Luchinat C, Gao X, Zeri AC, Gowda GA, Raftery D, Steinbeck C, Salek RM, Wishart DS Abstract NMR-based metabolomics has shown considerable promise in disease diagnosis and biomarker discovery because it allows one to non-destructively identify and quantify large numbers of novel metabolite biomarkers in both biofluids and tissues. Indeed, precise metabolite quantification is a necessary prerequisite to move any chemical biomarker or biomarker panel from the lab into the clinic. Among the many biofluids (urine, serum, plasma, cerebrospinal fluid and saliva) commonly used for disease diagnosis and prognosis, urine has several advantages. It is abundant, sterile, easily obtained, needs little sample preparation and does not require any invasive medical procedures for collection. Furthermore, urine captures and concentrates many "unwanted" or "undesirable" compounds throughout the body, thereby providing a rich source of potentially useful disease biomarkers. However, the incredible variation in urine chemical concentrations due to effects such as gender, age, diet, life style, health conditions, and physical activity make the analysis of urine and the identification of useful urinary biomarkers by NMR quite challenging. In this review, we discuss a number of the most significant issues regarding NMR-based urinary metabolomics with a specific emphasis on metabolite quantification for disease biomarker applications. We also propose a number of data collection and instrumental recommendations regarding NMR pulse sequences, acceptable acquisition parameter ranges, relaxation effects on quantitation, proper handling of instrumental differences, as well as recommendations regarding sample preparation and biomarker assessment. PMID: 26745651 [PubMed - as supplied by publisher]

Aberrant purine metabolism in allergic asthma revealed by plasma metabolomics. J Pharm Biomed Anal. 2015 Dec 17;120:181-189 Authors: Yu M, Cui FX, Jia HM, Zhou C, Yang Y, Zhang HW, Ding G, Zou ZM Abstract Asthma is a disease characterized by chronic relapsing airways, and its etiology remains incompletely understood. To better understand the metabolic phenotypes of asthma, we investigated a plasma metabolic signature associated with allergic asthma in ovalbumin (OVA)-sensitized mice by using ultra high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). Sixteen metabolites were characterized as potential pathological biomarkers related to asthma. Among them, 6 (dodecanoic acid (P1), myristic acid (P2), phytosphingosine (P3), sphinganine (P4), inosine (P13) and taurocholic acid (P15)) were first reported to have potential relevance in the pathogenesis of experimental asthma. The identified potential biomarkers were involved in 6 metabolic pathways and achieved the most entire metabolome contributing to the formation of allergic asthma. Purine metabolism was the most prominently influenced in OVA-induced asthma mice according to the metabolic pathway analysis (MetPA), suggesting that significantly changes in inflammatory responses in the pathophysiologic process of asthma. The metabolites of purine metabolism, especially uric acid (P12) and inosine (P13), may denote their potential as targeted biomarkers related to experimental asthma. The decreased plasma uric acid (P12) suggested that inflammation responses of allergic asthma inhibited the activity of xanthine oxidase in purine metabolism, and manifested the severity of asthma exacerbation. The increased level of inosine (P13) suggests that inflammatory cells induce adenosine triphosphate (ATP) breakdown, resulting in excessive expression of adenosine deaminase (ADA) in the formation of allergic asthma. These findings provided a novel perspective on the metabolites signatures related to allergic asthma, which provided us with new insights into the pathogenesis of asthma, and the discovery of targets for clinical diagnosis and treatment. PMID: 26744988 [PubMed - as supplied by publisher]

The ratio of phosphatidylcholines to lysophosphatidylcholines in plasma differentiates healthy controls from patients with Alzheimer's disease and mild cognitive impairment. Alzheimers Dement (Amst). 2015 Sep 2;1(3):295-302 Authors: Klavins K, Koal T, Dallmann G, Marksteiner J, Kemmler G, Humpel C Abstract BACKGROUND: Metabolomic processes have been identified as being strongly linked to the development of Alzheimer's disease (AD). Thus, lipid metabolites appear to be highly useful as diagnostic substrates for the diagnosis of AD and mild cognitive impairment (MCI) in plasma. METHODS: We analyzed plasma samples from controls (n = 35), MCI (n = 33), and AD patients (n = 43) using the AbsoluteIDQ p180 Kit (Biocrates Life Sciences), which included quantitative analysis of 40 acylcarnitines, 21 amino acids, 19 biogenic amines, 15 sphingolipids, 90 glycerophospholipids, and sum of hexoses. RESULTS: We found that individual lipid metabolites can differentiate controls from MCI and AD with relevant significance. However, the ratio between PC aa C34:4 and lysoPC a C18:2 differentiates controls from MCI (P = .0000007) and from AD (P = .0000009) with greater significance. CONCLUSIONS: The results provide evidence that the ratio of these two lipid metabolites is useful for diagnosing MCI and AD with an accuracy of 82%-85%. PMID: 26744734 [PubMed - as supplied by publisher]

Oxygen-dependent regulation of c-di-GMP synthesis by SadC controls alginate production in Pseudomonas aeruginosa. Environ Microbiol. 2016 Jan 6; Authors: Schmidt A, Hammerbacher AS, Bastian M, Nieken KJ, Klockgether J, Merighi M, Lapouge K, Poschgan C, Kölle J, Acharya KR, Ulrich M, Tümmler B, Unden G, Kaever V, Lory S, Haas D, Schwarz S, Döring G Abstract Pseudomonas aeruginosa produces increased levels of alginate in response to oxygen-deprived conditions. The regulatory pathway(s) that links oxygen limitation to increased synthesis of alginate has remained elusive. In the present study, using immunofluorescence microscopy, we show that anaerobiosis-induced alginate production by planktonic PAO1 requires the diguanylate cyclase (DGC) SadC, previously identified as a regulator of surface-associated lifestyles. Furthermore, we found that the gene products of PA4330 and PA4331, located in a predicted operon with sadC, have a major impact on alginate production: Deletion of PA4330 (odaA, for oxygen-dependent alginate synthesis activator) caused an alginate production defect under anaerobic conditions whereas a PA4331 (odaI, for oxygen-dependent alginate synthesis inhibitor) deletion mutant produced alginate also in the presence of oxygen, which would normally inhibit alginate synthesis. Based on their sequence, OdaA and OdaI have predicted hydratase and dioxygenase reductase activity, respectively. Enzymatic assays using purified protein showed that unlike OdaA, which did not significantly affect DGC activity of SadC, OdaI inhibited c-di-GMP production by SadC. Our data indicate that SadC, OdaA and OdaI are components of a novel response pathway of P. aeruginosa that regulates alginate synthesis in an oxygen-dependent manner. PMID: 26743546 [PubMed - as supplied by publisher]

An integrated strategy to quantitatively differentiate chemome between Cistanche deserticola and C. tubulosa using high performance liquid chromatography-hybrid triple quadrupole-linear ion trap mass spectrometry. J Chromatogr A. 2015 Dec 21; Authors: Song Y, Song Q, Li J, Zhang N, Zhao Y, Liu X, Jiang Y, Tu P Abstract It is important to conduct large-scale detection, identification, and quantitation of metabolites in a given sample. Herein, a practical strategy was proposed to quantitatively compare the chemome between Cistanche deserticola (CD) and C. tubulosa (CT), which have been widely believed as the ideal edible and medicinal plants for conquering the deserts. The entire workflow was implemented on high performance liquid chromatography-hybrid triple quadrupole-linear ion trap mass spectrometer and consisted of three primary steps: (1) component detection and identification, various mass spectrometric approaches were applied to globally screen the chemical constituents, and structural elucidation was achieved by comparing with authentic compounds, analyzing MS(2) spectra, and referring to the literature along with accessible databases; (2) comprehensive relative quantitation, scheduled multiple reaction monitoring algorithm was introduced for relative quantitation of all detected ingredients; and (3) chemome comparison, the quantitative dataset was subjected for multivariate statistical analysis to carry out comparative study. A total of 513 metabolites were detected and relatively quantitated, and 379 ones were annotated. Betaine, Krebs cycle intermediates, phenylethanoid glycosides, and iridoids were picked out as the chemical markers being responsible for the discrimination of the chemical profiles between CD and CT. Above all, the quantitative chemome of CD and CT were exhaustively characterized and compared, which could advance their values concerning drug development, economics, and desertification control. The proposed strategy is expected as a reliable choice for widely targeted metabolomics of plants. PMID: 26742897 [PubMed - as supplied by publisher]

Photodynamic treatment with hexyl-aminolevulinate mediates reversible thiol oxidation in core oxidative stress signaling proteins. Mol Biosyst. 2016 Jan 8; Authors: Helander L, Sharma A, Krokan HE, Plaetzer K, Krammer B, Tortik N, Gederaas OA, Slupphaug G, Hagen L Abstract Photodynamic therapy (PDT) is a highly selective two-step cancer treatment involving a photosensitizer and illumination with visible light in the presence of molecular oxygen. PDT is clinically approved worldwide for treating several premalignant conditions and cancer forms, especially endoscopically accessible tumors and dermatological malignancies. PDT-mediated cytotoxicity takes place via autophagy, apoptosis and necrosis, but the exact trigger mechanisms for various death-pathways are still unknown. PDT induces reactive oxygen species (ROS) through photochemical reactions. ROS can react with different macromolecules resulting in cellular damage, including oxidation of proteins. One of the known protein modifications is reversible oxidation of cysteine thiols (-SH), which in many cases constitute a redox switch to modulate protein activity and cellular signaling. Here we have examined the role of reversible oxidation of protein thiols as a potential mediator of cytotoxicity after hexylaminolevulinate-mediated photodynamic treatment (HAL-PDT) in the human epidermoid carcinoma cell line A431. Nearly 2300 proteins were found to be reversibly oxidized after HAL-PDT, of which 374 high-confidence proteins were further allocated to cellular compartments and functional networks. 115 of the high confidence proteins were associated with apoptosis and 257 have previously not been reported to be reversibly oxidized on cysteines. We find an enrichment of DNA damage checkpoint and oxidative stress response proteins. Many of these constitute potential signaling hubs in apoptosis, including ATM, p63, RSK1 p38, APE1/Ref-1 and three 14-3-3 family members. Our study represents the first comprehensive mapping of reversibly oxidized proteins subsequent to HAL-PDT. Several of the proteins constitute potentially novel redox-regulated apoptotic triggers as well as potential targets for adjuvants that may improve the efficacy of HAL-PDT and PDT using other photosensitizers. PMID: 26742548 [PubMed - as supplied by publisher]

Related Articles The evolution of plant secretory structures and emergence of terpenoid chemical diversity. Annu Rev Plant Biol. 2015;66:139-59 Authors: Lange BM Abstract Secretory structures in terrestrial plants appear to have first emerged as intracellular oil bodies in liverworts. In vascular plants, internal secretory structures, such as resin ducts and laticifers, are usually found in conjunction with vascular bundles, whereas subepidermal secretory cavities and epidermal glandular trichomes generally have more complex tissue distribution patterns. The primary function of plant secretory structures is related to defense responses, both constitutive and induced, against herbivores and pathogens. The ability to sequester secondary (or specialized) metabolites and defense proteins in secretory structures was a critical adaptation that shaped plant-herbivore and plant-pathogen interactions. Although this review places particular emphasis on describing the evolution of pathways leading to terpenoids, it also assesses the emergence of other metabolite classes to outline the metabolic capabilities of different plant lineages. PMID: 25621517 [PubMed - indexed for MEDLINE]

Related Articles Arsenite-induced pseudo-hypoxia results in loss of anchorage-dependent growth in BEAS-2B pulmonary epithelial cells. PLoS One. 2014;9(12):e114549 Authors: Zhao F, Malm SW, Hinchman AN, Li H, Beeks CG, Klimecki WT Abstract Epidemiology studies have established a strong link between lung cancer and arsenic exposure. Currently, the role of disturbed cellular energy metabolism in carcinogenesis is a focus of scientific interest. Hypoxia inducible factor-1 alpha (HIF-1A) is a key regulator of energy metabolism, and it has been found to accumulate during arsenite exposure under oxygen-replete conditions. We modeled arsenic-exposed human pulmonary epithelial cells in vitro with BEAS-2B, a non-malignant lung epithelial cell line. Constant exposure to 1 µM arsenite (As) resulted in the early loss of anchorage-dependent growth, measured by soft agar colony formation, beginning at 6 weeks of exposure. This arsenite exposure resulted in HIF-1A accumulation and increased glycolysis, similar to the physiologic response to hypoxia, but in this case under oxygen-replete conditions. This "pseudo-hypoxia" response was necessary for the maximal acquisition of anchorage-independent growth in arsenite-exposed BEAS-2B. The HIF-1A accumulation and induction in glycolysis was sustained throughout a 52 week course of arsenite exposure in BEAS-2B. There was a time-dependent increase in anchorage-independent growth during the exposure to arsenite. When HIF-1A expression was stably suppressed, arsenite-induced glycolysis was abrogated, and the anchorage-independent growth was reduced. These findings establish that arsenite exerts a hypoxia-mimetic effect, which plays an important role in the subsequent gain of malignancy-associated phenotypes. PMID: 25513814 [PubMed - indexed for MEDLINE]

Related Articles Metabolomic perfusate analysis during kidney machine perfusion: the pig provides an appropriate model for human studies. PLoS One. 2014;9(12):e114818 Authors: Nath J, Guy A, Smith TB, Cobbold M, Inston NG, Hodson J, Tennant DA, Ludwig C, Ready AR Abstract INTRODUCTION: Hypothermic machine perfusion offers great promise in kidney transplantation and experimental studies are needed to establish the optimal conditions for this to occur. Pig kidneys are considered to be a good model for this purpose and share many properties with human organs. However it is not established whether the metabolism of pig kidneys in such hypothermic hypoxic conditions is comparable to human organs. METHODS: Standard criteria human (n = 12) and porcine (n = 10) kidneys underwent HMP using the LifePort Kidney Transporter 1.0 (Organ Recovery Systems) using KPS-1 solution. Perfusate was sampled at 45 minutes and 4 hours of perfusion and metabolomic analysis performed using 1-D 1H-NMR spectroscopy. RESULTS: There was no inter-species difference in the number of metabolites identified. Of the 30 metabolites analysed, 16 (53.3%) were present in comparable concentrations in the pig and human kidney perfusates. The rate of change of concentration for 3-Hydroxybutyrate was greater for human kidneys (p<0.001). For the other 29 metabolites (96.7%), there was no difference in the rate of change of concentration between pig and human samples. CONCLUSIONS: Whilst there are some differences between pig and human kidneys during HMP they appear to be metabolically similar and the pig seems to be a valid model for human studies. PMID: 25502759 [PubMed - indexed for MEDLINE]

Related Articles (1)H-NMR analysis provides a metabolomic profile of patients with multiple sclerosis. Neurol Neuroimmunol Neuroinflamm. 2016 Feb;3(1):e185 Authors: Cocco E, Murgia F, Lorefice L, Barberini L, Poddighe S, Frau J, Fenu G, Coghe G, Murru MR, Murru R, Del Carratore F, Atzori L, Marrosu MG Abstract OBJECTIVE: To investigate the metabolomic profiles of patients with multiple sclerosis (MS) and to define the metabolic pathways potentially related to MS pathogenesis. METHODS: Plasma samples from 73 patients with MS (therapy-free for at least 90 days) and 88 healthy controls (HC) were analyzed by (1)H-NMR spectroscopy. Data analysis was conducted with principal components analysis followed by a supervised analysis (orthogonal partial least squares discriminant analysis [OPLS-DA]). The metabolites were identified and quantified using Chenomx software, and the receiver operating characteristic (ROC) curves were calculated. RESULTS: The model obtained with the OPLS-DA identified predictive metabolic differences between the patients with MS and HC (R2X = 0.615, R2Y = 0.619, Q2 = 0.476; p < 0.001). The differential metabolites included glucose, 5-OH-tryptophan, and tryptophan, which were lower in the MS group, and 3-OH-butyrate, acetoacetate, acetone, alanine, and choline, which were higher in the MS group. The suitability of the model was evaluated using an external set of samples. The values returned by the model were used to build the corresponding ROC curve (area under the curve of 0.98). CONCLUSION: NMR metabolomic analysis was able to discriminate different metabolic profiles in patients with MS compared with HC. With the exception of choline, the main metabolic changes could be connected to 2 different metabolic pathways: tryptophan metabolism and energy metabolism. Metabolomics appears to represent a promising noninvasive approach for the study of MS. PMID: 26740964 [PubMed]

Related Articles The 2016 database issue of Nucleic Acids Research and an updated molecular biology database collection. Nucleic Acids Res. 2016 Jan 4;44(D1):D1-6 Authors: Rigden DJ, Fernández-Suárez XM, Galperin MY Abstract The 2016 Database Issue of Nucleic Acids Research starts with overviews of the resources provided by three major bioinformatics centers, the U.S. National Center for Biotechnology Information (NCBI), the European Bioinformatics Institute (EMBL-EBI) and Swiss Institute for Bioinformatics (SIB). Also included are descriptions of 62 new databases and updates on 95 databases that have been previously featured in NAR plus 17 previously described elsewhere. A number of papers in this issue deal with resources on nucleic acids, including various kinds of non-coding RNAs and their interactions, molecular dynamics simulations of nucleic acid structure, and two databases of super-enhancers. The protein database section features important updates on the EBI's Pfam, PDBe and PRIDE databases, as well as a variety of resources on pathways, metabolomics and metabolic modeling. This issue also includes updates on popular metagenomics resources, such as MG-RAST, EBI Metagenomics, and probeBASE, as well as a newly compiled Human Pan-Microbe Communities database. A significant fraction of the new and updated databases are dedicated to the genetic basis of disease, primarily cancer, and various aspects of drug research, including resources for patented drugs, their side effects, withdrawn drugs, and potential drug targets. A further six papers present updated databases of various antimicrobial and anticancer peptides. The entire Database Issue is freely available online on the Nucleic Acids Research website (http://nar.oxfordjournals.org/). The NAR online Molecular Biology Database Collection, http://www.oxfordjournals.org/nar/database/c/, has been updated with the addition of 88 new resources and removal of 23 obsolete websites, which brought the current listing to 1685 databases. PMID: 26740669 [PubMed - in process]

Related Articles Foraging at wastewater treatment works affects brown adipose tissue fatty acid profiles in banana bats. Biol Open. 2016 Jan 6; Authors: Hill K, van Aswegen S, Schoeman MC, Claassens S, Jansen van Rensburg P, Naidoo S, Vosloo D Abstract In this study we tested the hypothesis that the decrease in habitat quality at wastewater treatment works (WWTW), such as limited prey diversity and exposure to the toxic cocktail of pollutants, affect fatty acid profiles of interscapular brown adipose tissue (iBrAT) in bats. Further, the antioxidant capacity of oxidative tissues such as pectoral and cardiac muscle may not be adequate to protect those tissues against reactive molecules resulting from polyunsaturated fatty acid auto-oxidation in the WWTW bats. Bats were sampled at two urban WWTW, and two unpolluted reference sites in KwaZulu-Natal, South Africa. Brown adipose tissue (BrAT) mass was lower in WWTW bats than in reference site bats. We found lower levels of saturated phospholipid fatty acids and higher levels of mono- and polyunsaturated fatty acids in WWTW bats than in reference site bats, while C18 desaturation and n-6 to n-3 ratios were higher in the WWTW bats. This was not associated with high lipid peroxidation levels in pectoral and cardiac muscle. Combined, these results indicate that WWTW bats rely on iBrAT as an energy source, and opportunistic foraging on abundant, pollutant-tolerant prey may change fatty acid profiles in their tissue, with possible effects on mitochondrial functioning, torpor and energy usage. PMID: 26740572 [PubMed - as supplied by publisher]

Related Articles Editorial on "Sample normalization methods in quantitative metabolomics" by Yiman Wu and Liang Li. J Chromatogr A. 2015 Dec 14; Authors: Giese RW PMID: 26739914 [PubMed - as supplied by publisher]

Related Articles Natural product discovery: past, present, and future. J Ind Microbiol Biotechnol. 2016 Jan 6; Authors: Katz L, Baltz RH Abstract Microorganisms have provided abundant sources of natural products which have been developed as commercial products for human medicine, animal health, and plant crop protection. In the early years of natural product discovery from microorganisms (The Golden Age), new antibiotics were found with relative ease from low-throughput fermentation and whole cell screening methods. Later, molecular genetic and medicinal chemistry approaches were applied to modify and improve the activities of important chemical scaffolds, and more sophisticated screening methods were directed at target disease states. In the 1990s, the pharmaceutical industry moved to high-throughput screening of synthetic chemical libraries against many potential therapeutic targets, including new targets identified from the human genome sequencing project, largely to the exclusion of natural products, and discovery rates dropped dramatically. Nonetheless, natural products continued to provide key scaffolds for drug development. In the current millennium, it was discovered from genome sequencing that microbes with large genomes have the capacity to produce about ten times as many secondary metabolites as was previously recognized. Indeed, the most gifted actinomycetes have the capacity to produce around 30-50 secondary metabolites. With the precipitous drop in cost for genome sequencing, it is now feasible to sequence thousands of actinomycete genomes to identify the "biosynthetic dark matter" as sources for the discovery of new and novel secondary metabolites. Advances in bioinformatics, mass spectrometry, proteomics, transcriptomics, metabolomics and gene expression are driving the new field of microbial genome mining for applications in natural product discovery and development. PMID: 26739136 [PubMed - as supplied by publisher]

Related Articles Effects of Parental Temperature and Nitrate on Seed Performance are Reflected by Partly Overlapping Genetic and Metabolic Pathways. Plant Cell Physiol. 2016 Jan 6; Authors: He H, Willems L, Batushansky A, Fait A, Hanson J, Nijveen H, Hilhorst HW, Bentsink L Abstract Seed performance is affected by the seed maturation environment and previously, we have shown that temperature, nitrate and light intensity were the most influential environmental factors affecting seed performance. Seeds developed in these environments were selected to assess the underlying metabolic pathways, using a combination of transcriptomics and metabolomics. These analyses revealed that the effects of the temperature and nitrate parental environments were reflected by partly overlapping genetic and metabolic networks, as indicated by similar changes in metabolites and transcripts expression levels. Nitrogen-metabolism related metabolites (asparagine, GABA and allantoin) were significantly decreased in both low temperature (15°C) and low nitrate (N0) maturation environments. Correspondingly, nitrogen-metabolism genes (ALLANTOINASE, NITRATE REDUCTASE 1, NITRITE REDUCTASE 1 and NITRILASE 4) were differentially regulated in the low temperature and nitrate maturation environments, as compared with control conditions. High light intensity during seed maturation increased galactinol content, and displayed a high correlation with seed longevity. Low light had a genotype-specific effect on cell surface encoding genes in the DELAY OF GERMINATION 6-Near Isogenic Line (NILDOG6). Overall, the integration of phenotypes, metabolites and transcripts led to new insights in the regulation of seed performance. PMID: 26738545 [PubMed - as supplied by publisher]

Related Articles Proteomic and metabolomic analyses provide insight into production of volatile and non-volatile flavor components in mandarin hybrid fruit. BMC Plant Biol. 2015;15:76 Authors: Yu Q, Plotto A, Baldwin EA, Bai J, Huang M, Yu Y, Dhaliwal HS, Gmitter FG Abstract BACKGROUND: Although many of the volatile constituents of flavor and aroma in citrus have been identified, the knowledge of molecular mechanisms and regulation of volatile production are very limited. Our aim was to understand mechanisms of flavor volatile production and regulation in mandarin fruit. RESULT: Fruits of two mandarin hybrids, Temple and Murcott with contrasting volatile and non- volatile profiles, were collected at three developmental stages. A combination of methods, including the isobaric tags for relative and absolute quantification (iTRAQ), quantitative real-time polymerase chain reaction, gas chromatography, and high-performance liquid chromatography, was used to identify proteins, measure gene expression levels, volatiles, sugars, organic acids and carotenoids. Two thirds of differentially expressed proteins were identified in the pathways of glycolysis, citric acid cycle, amino acid, sugar and starch metabolism. An enzyme encoding valencene synthase gene (Cstps1) was more abundant in Temple than in Murcott. Valencene accounted for 9.4% of total volatile content in Temple, whereas no valencene was detected in Murcott fruit. Murcott expression of Cstps1 is severely reduced. CONCLUSION: We showed that the diversion of valencene and other sesquiterpenes into the terpenoid pathway together with high production of apocarotenoid volatiles might have resulted in the lower concentration of carotenoids in Temple fruit. PMID: 25848837 [PubMed - indexed for MEDLINE]

Related Articles Comparative metabolic and transcriptional analysis of a doubled diploid and its diploid citrus rootstock (C. junos cv. Ziyang xiangcheng) suggests its potential value for stress resistance improvement. BMC Plant Biol. 2015;15:89 Authors: Tan FQ, Tu H, Liang WJ, Long JM, Wu XM, Zhang HY, Guo WW Abstract BACKGROUND: Polyploidy has often been considered to confer plants a better adaptation to environmental stresses. Tetraploid citrus rootstocks are expected to have stronger stress tolerance than diploid. Plenty of doubled diploid citrus plants were exploited from diploid species for citrus rootstock improvement. However, limited metabolic and molecular information related to tetraploidization is currently available at a systemic biological level. This study aimed to evaluate the occurrence and extent of metabolic and transcriptional changes induced by tetraploidization in Ziyang xiangcheng (Citrus junos Sieb. ex Tanaka), which is a special citrus germplasm native to China and widely used as an iron deficiency tolerant citrus rootstock. RESULTS: Doubled diploid Ziyang xiangcheng has typical morphological and anatomical features such as shorter plant height, larger and thicker leaves, bigger stomata and lower stomatal density, compared to its diploid parent. GC-MS (Gas chromatography coupled to mass spectrometry) analysis revealed that tetraploidization has an activation effect on the accumulation of primary metabolites in leaves; many stress-related metabolites such as sucrose, proline and γ-aminobutyric acid (GABA) was remarkably up-regulated in doubled diploid. However, LC-QTOF-MS (Liquid chromatography quadrupole time-of-flight mass spectrometry) analysis demonstrated that tetraploidization has an inhibition effect on the accumulation of secondary metabolites in leaves; all the 33 flavones were down-regulated while all the 6 flavanones were up-regulated in 4x. By RNA-seq analysis, only 212 genes (0.8% of detected genes) are found significantly differentially expressed between 2x and 4x leaves. Notably, those genes were highly related to stress-response functions, including responses to salt stress, water and abscisic acid. Interestingly, the transcriptional divergence could not explain the metabolic changes, probably due to post-transcriptional regulation. CONCLUSION: Taken together, tetraploidization induced considerable changes in leaf primary and secondary metabolite accumulation in Ziyang xiangcheng. However, the effect of tetraploidization on transcriptome is limited. Compared to diploid, higher expression level of stress related genes and higher content of stress related metabolites in doubled diploid could be beneficial for its stress tolerance. PMID: 25848687 [PubMed - indexed for MEDLINE]

Related Articles Urinary metabonomics elucidate the therapeutic mechanism of Orthosiphon stamineus in mouse crystal-induced kidney injury. J Ethnopharmacol. 2015 May 26;166:323-32 Authors: Gao S, Chen W, Peng Z, Li N, Su L, Lv D, Li L, Lin Q, Dong X, Guo Z, Lou Z Abstract ETHNOPHARMACOLOGICAL RELEVANCE: Orthosiphon stamineus (OS), a traditional Chinese herb, is often used for promoting urination and treating nephrolithiasis. AIM OF THE STUDY: Urolithiasis is a major worldwide public health burden due to its high incidence of recurrence and damage to renal function. However, the etiology for urolithiasis is not well understood. Metabonomics, the systematic study of small molecule metabolites present in biological samples, has become a valid and powerful tool for understanding disease phenotypes. In this study, a urinary metabolic profiling analysis was performed in a mouse model of renal calcium oxalate crystal deposition to identify potential biomarkers for crystal-induced renal damage and the anti-crystal mechanism of OS. MATERIALS AND METHODS: Thirty six mice were randomly divided into six groups including Saline, Crystal, Cystone and OS at dosages of 0.5g/kg, 1g/kg, and 2g/kg. A metabonomics approach using ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was developed to perform the urinary metabolic profiling analysis. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were utilized to identify differences between the metabolic profiles of mice in the saline control group and crystal group. RESULTS: Using partial least squares-discriminant analysis, 30 metabolites were identified as potential biomarkers of crystal-induced renal damage. Most of them were primarily involved in amino acid metabolism, taurine and hypotaurine metabolism, purine metabolism, and the citrate cycle (TCA). After the treatment with OS, the levels of 20 biomarkers had returned to the levels of the control samples. CONCLUSIONS: Our results suggest that OS has a protective effect for mice with crystal-induced kidney injury via the regulation of multiple metabolic pathways primarily involving amino acid, energy and choline metabolism. PMID: 25794803 [PubMed - indexed for MEDLINE]

Related Articles Non-targeted metabolomic profile of Fagus sylvatica L. leaves using liquid chromatography with mass spectrometry and gas chromatography with mass spectrometry. Phytochem Anal. 2015 Mar-Apr;26(2):171-82 Authors: Cadahía E, Fernández de Simón B, Aranda I, Sanz M, Sánchez-Gómez D, Pinto E Abstract INTRODUCTION: Fagus sylvatica L. is one of the most widely distributed broad-leaved tree species in central and western Europe, important to the forest sector and an accurate biomarker of climate change. OBJECTIVE: To profile the beech leaf metabolome for future studies in order to investigate deeper into the characterisation of its metabolic response. METHODS: Leaf extracts were analysed using LC-MS by electrospray ionisation in negative mode from m/z 100-1700 and GC-MS by electron ionisation in scan mode from m/z 35-800. RESULTS: The LC-MS profile resulted in 56 compounds, of which 43 were identified and/or structurally characterised, including hydroxycinnamic acid derivatives, flavan-3-ols and proanthocyanidins, and flavonols. From a second analysis based on GC-MS, a total of 111 compounds were identified, including carbohydrates, polyalcohols, amino acids, organic acids, fatty acids, phenolic compounds, terpenoids, sterols and other related compounds. Many of the compounds identified were primary metabolites involved in major plant metabolic pathways, however, some secondary metabolites were also detected. Some of them play roles as tolerance-response osmoregulators and osmoprotectors in abiotic stress, or as anti-oxidants that reduce the effect of reactive oxygen species and promote many protective functions in plants. CONCLUSIONS: This study provides a broad and relevant insight into the metabolic status of F. sylvatica leaves, and serves as a base for future studies on physiological and molecular mechanisms involved in biotic or abiotic stress. PMID: 25516018 [PubMed - indexed for MEDLINE]

Metabolomic pathway visualization tool outsourcing editing function. Conf Proc IEEE Eng Med Biol Soc. 2015 Aug;2015:7659-7662 Authors: Sugimoto M Abstract Recent rapid improvements of measuring instrument enables us to perform various omics studies to simultaneous profile multiple molecules, which provides a holistic view of various molecular interactions, such as signal transaction, protein interactions, and metabolic pathways. Metabolomics is recently emerged omics that can identify and quantify low weight metabolites usually defined as organic molecules whose size is <; 1500 Da. In comparison to the other omics, the development of software tools to deal with metabolomic data is not matured. Conventional pathway drawing and visualization tool provide tool-specific unique functions, however, such user interface requires users to learn the usage and prevention for the use of these tools. Here, we developed a more generic pathway visualization tool. This tool incorporate pathway data yielded by common drawing tools, e.g. MS PowerPoint, and visualize the quantified values on the pathways. The statistical results also can be overlaid on each metabolite. The developed tools facilitate the interpreting metabolomic data in pathway forms. PMID: 26738066 [PubMed - as supplied by publisher]