PubMed

MCEE: a data preprocessing approach for metabolic confounding effect elimination. Anal Bioanal Chem. 2018 Feb 24;: Authors: Li Y, Li M, Jia W, Ni Y, Chen T Abstract It is well recognized that physiological and environmental factors such as race, age, gender, and diurnal cycles often have a definite influence on metabolic results that statistically manifests as confounding variables. Currently, removal or controlling of confounding effects relies heavily on experimental design. There are no available data processing techniques focusing on the compensation of their effects. We therefore proposed a new method, Metabolic confounding effect elimination (MCEE), to remove the influence of specified confounding factors and make the data more accurate. The method consists of three steps: metabolites grouping, confounder-related metabolites selection, and metabolites modification. Its effectiveness and advantages were evaluated comprehensively by several simulated models and real datasets, and were compared with two typical methods, the principal component analysis (PCA)- and the direct orthogonal signal correction (DOSC)-based methods. MCEE is simple, effective, and safe, and is independent of sample number, association degree, and missing value. Hence, it may serve as a good complement to existing metabolomics data preprocessing methods and aid in better understanding the metabolic and biological status of interest. Graphical Abstract Processing flow and demo performance of MCEE to Algorithm flow and demo performance of MCEE. PMID: 29476235 [PubMed - as supplied by publisher]

The autophagic network and cancer. Nat Cell Biol. 2018 Mar;20(3):243-251 Authors: Rybstein MD, Bravo-San Pedro JM, Kroemer G, Galluzzi L Abstract Mammalian cells harness autophagy to eliminate physiological byproducts of metabolism and cope with microenvironmental perturbations. Moreover, autophagy connects cellular adaptation with extracellular circuitries that impinge on immunity and metabolism. As it links transformed and non-transformed components of the tumour microenvironment, such an autophagic network is important for cancer initiation, progression and response to therapy. Here, we discuss the mechanisms whereby the autophagic network interfaces with multiple aspects of malignant disease. PMID: 29476153 [PubMed - in process]

24 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 2018/02/24PubMed comprises more than millions of 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.

Changes in Metabolites Present in Lung Lining Fluid Following Exposure of Humans to Ozone. Toxicol Sci. 2018 Feb 19;: Authors: Cheng W, Duncan KE, Ghio AJ, Ward-Caviness C, Karoly ED, Diaz-Sanchez D, Conolly RB, Devlin RB Abstract Controlled human exposure to the oxidant air pollutant ozone causes decrements in lung function and increased inflammation as evidenced by neutrophil influx into the lung and increased levels of proinflammatory cytokines in the airways. Here we describe a targeted metabolomics evaluation of human bronchioalveolar lavage fluid (BALF) following controlled in vivo exposure to ozone to gain greater insight into its pulmonary effects. In a two-arm cross-over study, each healthy adult human volunteer was randomly exposed to filtered air (FA) and to 0.3 ppm ozone for 2 hr while undergoing intermittent exercise with a minimum of 4 weeks between exposures. Bronchoscopy was performed and BALF obtained at 1 (n = 9) or 24 (n = 23) h post-exposure. Metabolites were detected using ultrahigh performance liquid chromatography-tandem mass spectroscopy. At 1-hour post-exposure, a total of 28 metabolites were differentially expressed (DE) (p < 0.05) following ozone exposure compared to FA-exposure. These changes were associated with increased glycolysis and antioxidant responses, suggesting a rapid increased energy utilization as part of the cellular response to oxidative stress. At 24-hour post-exposure, 41 metabolites were DE. Many of the changes were in amino acids and linked with enhanced proteolysis. Changes associated with increased lipid membrane turnover were also observed. These later-stage changes were consistent with ongoing repair of airway tissues. There were 1.37 times as many metabolites were differentially expressed at 24 hour compared to 1-hour post-exposure. The changes at 1 hour reflect responses to oxidative stress while the changes at 24 hour indicate a broader set of responses consistent with tissue repair. These results illustrate the ability of metabolomic analysis to identify mechanistic features of ozone toxicity and aspects of the subsequent tissue response. PMID: 29471466 [PubMed - as supplied by publisher]

Mucosal and Systemic Responses of Immunogenic Vaccines Candidates against enteric Escherichia coli infections in ruminants: A review. Microb Pathog. 2018 Feb 19;: Authors: Lawan A, Jesse FFA, Idris UH, Odhah MN, Arsalan M, Muhammad NA, Bhutto KR, Damudu Peter I, Abraham GA, Wahid AH, Mohd-Azmi ML, Zamri-Saad M Abstract Innumerable Escherichia coli of animal origin are identified, which are of economic significance, likewise, cattle, sheep and goats are the carrier of enterohaemorrhagic E. coli, which are less pathogenic, and can spread to people by way of direct contact and through the contamination of foodstuff or portable drinking water, causing serious illness. The immunization of ruminants has been carried out for ages and is largely acknowledged as the most economical and maintainable process of monitoring E. coli infection in ruminants. Yet, only a limited number of E. coli vaccines are obtainable. Mucosal surfaces are the most important ingress for E. coli and thus mucosal immune responses function as the primary means of fortification. Largely contemporary vaccination processes are done by parenteral administration and merely limited number of E. coli vaccines are inoculated via mucosal itinerary, due to its decreased efficacy. Nevertheless, aiming at maximal mucosal partitions to stimulate defensive immunity at both mucosal compartments and systemic site epitomises a prodigious task. Enormous determinations are involved in order to improve on novel mucosal E. coli vaccines candidate by choosing apposite antigens with potent immunogenicity, manipulating novel mucosal itineraries of inoculation and choosing immune-inducing adjuvants. The target of E. coli mucosal vaccines is to stimulate a comprehensive, effective and defensive immunity by specifically counteracting the antibodies at mucosal linings and by the stimulation of cellular immunity. Furthermore, effective E. coli mucosal vaccine would make vaccination measures stress-free and appropriate for large number of inoculation. On account of contemporary advancement in proteomics, metagenomics, metabolomics and transcriptomics research, a comprehensive appraisal of the immeasurable genes and proteins that were divulged by a bacterium is now in easy reach. Moreover, there exist marvellous prospects in this bourgeoning technologies in comprehending the host bacteria affiliation. Accordingly, the flourishing knowledge could massively guarantee to the progression of immunogenic vaccines against E. coli infections in both humans and animals. This review highlight and expounds on the current prominence of mucosal and systemic immunogenic vaccines for the prevention of E. coli infections in ruminants. PMID: 29471137 [PubMed - as supplied by publisher]

A urinary biosignature for mitochondrial myopathy, encephalopathy, lactic acidosis and stroke like episodes (MELAS). Mitochondrion. 2018 Feb 19;: Authors: Esterhuizen K, Zander Lindeque J, Mason S, van der Westhuizen FH, Suomalainen A, Hakonen AH, Carroll CJ, Rodenburg RJ, de Laat PB, Janssen MCH, Smeitink JAM, Louw R Abstract We used a comprehensive metabolomics approach to study the altered urinary metabolome of two mitochondrial myopathy, encephalopathy lactic acidosis and stroke like episodes (MELAS) cohorts carrying the m.3243A>G mutation. The first cohort were used in an exploratory phase, identifying 36 metabolites that were significantly perturbed by the disease. During the second phase, the 36 selected metabolites were able to separate a validation cohort of MELAS patients completely from their respective control group, suggesting usefulness of these 36 markers as a diagnostic set. Many of the 36 perturbed metabolites could be linked to an altered redox state, fatty acid catabolism and one-carbon metabolism. However, our evidence indicates that, of all the metabolic perturbations caused by MELAS, stalled fatty acid oxidation prevailed as being particularly disturbed. The strength of our study was the utilization of five different analytical platforms to generate the robust metabolomics data reported here. We show that urine may be a useful source for disease-specific metabolomics data, linking, amongst others, altered one-carbon metabolism to MELAS. The results reported here are important in our understanding of MELAS and might lead to better treatment options for the disease. PMID: 29471047 [PubMed - as supplied by publisher]

Arctic, Antarctic, and temperate green algae Zygnema spp. under UV-B stress: vegetative cells perform better than pre-akinetes. Protoplasma. 2018 Feb 22;: Authors: Holzinger A, Albert A, Aigner S, Uhl J, Schmitt-Kopplin P, Trumhová K, Pichrtová M Abstract Species of Zygnema form macroscopically visible mats in polar and temperate terrestrial habitats, where they are exposed to environmental stresses. Three previously characterized isolates (Arctic Zygnema sp. B, Antarctic Zygnema sp. C, and temperate Zygnema sp. S) were tested for their tolerance to experimental UV radiation. Samples of young vegetative cells (1 month old) and pre-akinetes (6 months old) were exposed to photosynthetically active radiation (PAR, 400-700 nm, 400 μmol photons m-2 s-1) in combination with experimental UV-A (315-400 nm, 5.7 W m-2, no UV-B), designated as PA, or UV-A (10.1 W m-2) + UV-B (280-315 nm, 1.0 W m-2), designated as PAB. The experimental period lasted for 74 h; the radiation period was 16 h PAR/UV-A per day, or with additional UV-B for 14 h per day. The effective quantum yield, generally lower in pre-akinetes, was mostly reduced during the UV treatment, and recovery was significantly higher in young vegetative cells vs. pre-akinetes during the experiment. Analysis of the deepoxidation state of the xanthophyll-cycle pigments revealed a statistically significant (p < 0.05) increase in Zygnema spp. C and S. The content of UV-absorbing phenolic compounds was significantly higher (p < 0.05) in young vegetative cells compared to pre-akinetes. In young vegetative Zygnema sp. S, these phenolic compounds significantly increased (p < 0.05) upon PA and PAB. Transmission electron microscopy showed an intact ultrastructure with massive starch accumulations at the pyrenoids under PA and PAB. A possible increase in electron-dense bodies in PAB-treated cells and the occurrence of cubic membranes in the chloroplasts are likely protection strategies. Metabolite profiling by non-targeted RP-UHPLC-qToF-MS allowed a clear separation of the strains, but could not detect changes due to the PA and PAB treatments. Six hundred seventeen distinct molecular masses were detected, of which around 200 could be annotated from databases. These results indicate that young vegetative cells can adapt better to the experimental UV-B stress than pre-akinetes. PMID: 29470709 [PubMed - as supplied by publisher]

Metabolomics in Plant Stress Physiology. Adv Biochem Eng Biotechnol. 2018 Feb 23;: Authors: Ghatak A, Chaturvedi P, Weckwerth W Abstract Metabolomics is an essential technology for functional genomics and systems biology. It plays a key role in functional annotation of genes and understanding towards cellular and molecular, biotic and abiotic stress responses. Different analytical techniques are used to extend the coverage of a full metabolome. The commonly used techniques are NMR, CE-MS, LC-MS, and GC-MS. The choice of a suitable technique depends on the speed, sensitivity, and accuracy. This chapter provides insight into plant metabolomic techniques, databases used in the analysis, data mining and processing, compound identification, and limitations in metabolomics. It also describes the workflow of measuring metabolites in plants. Metabolomic studies in plant responses to stress are a key research topic in many laboratories worldwide. We summarize different approaches and provide a generic overview of stress responsive metabolite markers and processes compiled from a broad range of different studies. Graphical Abstract. PMID: 29470599 [PubMed - as supplied by publisher]

RaMP: A Comprehensive Relational Database of Metabolomics Pathways for Pathway Enrichment Analysis of Genes and Metabolites. Metabolites. 2018 Feb 22;8(1): Authors: Zhang B, Hu S, Baskin E, Patt A, Siddiqui JK, Mathé EA Abstract The value of metabolomics in translational research is undeniable, and metabolomics data are increasingly generated in large cohorts. The functional interpretation of disease-associated metabolites though is difficult, and the biological mechanisms that underlie cell type or disease-specific metabolomics profiles are oftentimes unknown. To help fully exploit metabolomics data and to aid in its interpretation, analysis of metabolomics data with other complementary omics data, including transcriptomics, is helpful. To facilitate such analyses at a pathway level, we have developed RaMP (Relational database of Metabolomics Pathways), which combines biological pathways from the Kyoto Encyclopedia of Genes and Genomes (KEGG), Reactome, WikiPathways, and the Human Metabolome DataBase (HMDB). To the best of our knowledge, an off-the-shelf, public database that maps genes and metabolites to biochemical/disease pathways and can readily be integrated into other existing software is currently lacking. For consistent and comprehensive analysis, RaMP enables batch and complex queries (e.g., list all metabolites involved in glycolysis and lung cancer), can readily be integrated into pathway analysis tools, and supports pathway overrepresentation analysis given a list of genes and/or metabolites of interest. For usability, we have developed a RaMP R package (https://github.com/Mathelab/RaMP-DB), including a user-friendly RShiny web application, that supports basic simple and batch queries, pathway overrepresentation analysis given a list of genes or metabolites of interest, and network visualization of gene-metabolite relationships. The package also includes the raw database file (mysql dump), thereby providing a stand-alone downloadable framework for public use and integration with other tools. In addition, the Python code needed to recreate the database on another system is also publicly available (https://github.com/Mathelab/RaMP-BackEnd). Updates for databases in RaMP will be checked multiple times a year and RaMP will be updated accordingly. PMID: 29470400 [PubMed]

Plant-derived polyphenols in human health: biological activity, metabolites and putative molecular targets. Curr Drug Metab. 2018 Feb 19;: Authors: Olivares-Vicente M, Barrajon-Catalan E, Herranz-Lopez M, Segura-Carretero A, Joven J, Encinar JA, Micol V Abstract Edible plants such as Hibiscus sabdariffa, Lippia citriodora, Rosmarinus officinalis and Olea europaea, are rich in bioactive compounds that represent most of the phenolic compounds families and have exhibited potential benefits in human health. These plants have been commonly used in folk medicine for their potential therapeutic properties in human chronic diseases. Recent evidence on these plants leads to postulate that polyphenols may account for such effects. Nevertheless, the compounds or metabolites that are responsible for reaching the molecular targets are still unknown. Data based on studies that directly use complex extracts on cellular models, without considering metabolic aspects, have limited applicability. In contrast, studies exploring the absorption process, metabolites in the blood circulation and tissues have become essential to identify the intracellular final effectors that are responsible for extracts bioactivity. Once the cellular metabolites are identified, computational molecular docking techniques suppose a unique tool for virtually screening a large number of compounds on selected protein targets in order to elucidate their potential mechanisms. In this review, we provide an updated overview of the in vitro and in vivo studies on the toxicity, absorption, permeability, pharmacokinetics and cellular metabolism of bioactive compounds derived from the abovementioned plants to identify the potential compounds that are responsible for the observed health effects. We also propose the use of in silico studies to virtually screen metabolites on selected protein targets, in combination with targeted metabolomics with high resolution mass spectrometry and using the candidate metabolites in cellular models, as the method of choice for elucidating the molecular mechanisms of these compounds.  . PMID: 29468962 [PubMed - as supplied by publisher]

Related Articles Urinary Metabolomics Profiles Associated to Bovine Meat Ingestion in Humans. Mol Nutr Food Res. 2018 Feb 22;: Authors: Khodorova NV, Rutledge DN, Oberli M, Mathiron D, Marcelo P, Benamouzig R, Tomé D, Gaudichon C, Pilard S Abstract SCOPE: The impact of meat consumption on human health is widely examined in nutritional epidemiological studies, especially due to the connexion between the consumption of red and processed meat and the risk of colon cancer. Food questionnaires do not assess the exposure to different methods of meat cooking. This study aimed to identify biomarkers of the acute ingestion of bovine meat cooked with 2 different processes. METHODS AND RESULTS: Non-targeted UPLC-MS metabolite profiling was done on urine samples obtained from 24 healthy volunteers before and 8h after the ingestion of a single meal composed of intrinsically 15 N labelled bovine meat, either cooked at 55 °C for 5 min or at 90 °C for 30 min. A Discriminant Analysis extension of Independent Components Analysis was applied to the mass spectral data. After meat ingestion, the urinary excretion of 1-methylhistidine, phenylacetylglutamine and short and medium-chained acylcarnitines was observed. 15 N labelling was detected in these metabolites thus confirming their origin from ingested meat. However, no difference was observed in urinary metabolomic profiles according to the meat cooking process used. CONCLUSION: Meat ingestion led to the excretion of several nitrogen-containing compounds, but although a metabolic signature was detected for meat ingestion, the impact of cooking process was not detectable at the level of urinary metabolic signature in our experimental conditions. This article is protected by copyright. All rights reserved. PMID: 29468821 [PubMed - as supplied by publisher]

Related Articles Evidence for Shikonin acting as an active inhibitor of human carboxylesterases 2: Implications for herb-drug combination. Phytother Res. 2018 Feb 22;: Authors: Li JN, Cao YF, He RR, Ge GB, Guo B, Wu JJ Abstract Shikonin, a natural naphthoquinone compound derived from the herb Lithospermum erythrorhizon, is widely used for its various pharmacological activities. However, its potential interactions with other medications by inhibiting human carboxylesterases 2 (hCE2) remain unknown. In this study, the inhibitory effects of shikonin on the activity of hCE2 in human liver microsomes are investigated by using fluorescein diacetate (FD), N-(2-butyl-1,3-dioxo-2,3-dihydro-1H-phenalen-6-yl)-2-chloroacetamide (NCEN), and CPT-11 as substrates of hCE2. The results demonstrate that shikonin significantly inhibits the activity of hCE2 when FD and NCEN are used as substrates, whereas the half inhibition concentration value of shikonin increased by 5-30 times when CPT-11 was used as the substrate. The inhibition types of shikonin against hCE2 activity reflected by 3 substrates were all best fit to noncompetitive manners. In addition, shikonin was found to distinctly suppress endogenous hCE2 activity, characterized with attenuated fluorescence. Furthermore, for drugs metabolized by hCE2 with the similar binding sites with FD or NCEN, the estimated magnitudes of area under the curve variation were approximately 9-357% in the presence of shikonin. Also, the area under the curve of CPT-11 could be increased by 1-14% following administration of shikonin. These findings have clear clinical implications for the combination of shikonin and hCE2-metabolizing prodrugs. PMID: 29468758 [PubMed - as supplied by publisher]

Related Articles Wheezing preschool children with early-onset asthma reveal a specific metabolomic profile. Pediatr Allergy Immunol. 2018 Feb 22;: Authors: Carraro S, Bozzetto S, Giordano G, El Mazloum D, Stocchero M, Pirillo P, Zanconato S, Baraldi E Abstract BACKGROUND: Many children of preschool age present with recurrent wheezing. Most of them outgrow their symptoms, while some have early-onset asthma. Aim of this prospective preliminary study was to apply a metabolomic approach to see whether biochemical-metabolic urinary profiles can have a role in the early identification of the children with asthma. METHODS: Preschool children with recurrent wheezing were recruited and followed up for 3 years, after which they were classified as cases of transient wheezing or early-onset asthma. A urine sample was collected at recruitment and analyzed using a metabolomic approach based on UPLC-mass spectrometry. RESULTS: Among 34 children aged 4.0±1.1 years recruited, at the end of the 3-year follow up, 16 were classified as having transient wheezing and 16 as cases of early-onset asthma. Through a joint multivariate and univariate statistical analysis we identified a subset of metabolomic variables that enabled the two groups to be clearly distinguished. The model built using the identified variables showed an AUC=0.99, and an AUC=0.88 on seven-fold full cross-validation(p=0.002). CONCLUSIONS: Metabolomic urinary profile can discriminate preschoolers with recurrent wheezing who will outgrow their symptoms from those who have early-onset asthma. These results may pave the way to the characterization of early non-invasive biomarkers capable of predicting asthma development. This article is protected by copyright. All rights reserved. PMID: 29468750 [PubMed - as supplied by publisher]

Related Articles Polyamines: Bio-Molecules with Diverse Functions in Plant and Human Health and Disease. Front Chem. 2018;6:10 Authors: Handa AK, Fatima T, Mattoo AK Abstract Biogenic amines-polyamines (PAs), particularly putrescine, spermidine and spermine are ubiquitous in all living cells. Their indispensable roles in many biochemical and physiological processes are becoming commonly known, including promoters of plant life and differential roles in human health and disease. PAs positively impact cellular functions in plants-exemplified by increasing longevity, reviving physiological memory, enhancing carbon and nitrogen resource allocation/signaling, as well as in plant development and responses to extreme environments. Thus, one or more PAs are commonly found in genomic and metabolomics studies using plants, particulary during different abiotic stresses. In humans, a general decline in PA levels with aging occurs parallel with some human health disorders. Also, high PA dose is detrimental to patients suffering from cancer, aging, innate immunity and cognitive impairment during Alzheimer and Parkinson diseases. A dichotomy exists in that while PAs may increase longevity and reduce some age-associated cardiovascular diseases, in disease conditions involving higher cellular proliferation, their intake has negative consequences. Thus, it is essential that PA levels be rigorously quantified in edible plant sources as well as in dietary meats. Such a database can be a guide for medical experts in order to recommend which foods/meats a patient may consume and which ones to avoid. Accordingly, designing both high and low polyamine diets for human consumption are in vogue, particularly in medical conditions where PA intake may be detrimental, for instance, cancer patients. In this review, literature data has been collated for the levels of the three main PAs, putrescine, spermidine and spermine, in different edible sources-vegetables, fruits, cereals, nuts, meat, sea food, cheese, milk, and eggs. Based on our analysis of vast literature, the effects of PAs in human/animal health fall into two broad, Yang and Yin, categories: beneficial for the physiological processes in healthy cells and detrimental under pathological conditions. PMID: 29468148 [PubMed]

Related Articles Antioxidant Phytochemicals in Fresh Produce: Exploitation of Genotype Variation and Advancements in Analytical Protocols. Front Chem. 2017;5:95 Authors: Manganaris GA, Goulas V, Mellidou I, Drogoudi P Abstract Horticultural commodities (fruit and vegetables) are the major dietary source of several bioactive compounds of high nutraceutical value for humans, including polyphenols, carotenoids and vitamins. The aim of the current review was dual. Firstly, toward the eventual enhancement of horticultural crops with bio-functional compounds, the natural genetic variation in antioxidants found in different species and cultivars/genotypes is underlined. Notably, some landraces and/or traditional cultivars have been characterized by substantially higher phytochemical content, i.e., small tomato of Santorini island (cv. "Tomataki Santorinis") possesses appreciably high amounts of ascorbic acid (AsA). The systematic screening of key bioactive compounds in a wide range of germplasm for the identification of promising genotypes and the restoration of key gene fractions from wild species and landraces may help in reducing the loss of agro-biodiversity, creating a healthier "gene pool" as the basis of future adaptation. Toward this direction, large scale comparative studies in different cultivars/genotypes of a given species provide useful insights about the ones of higher nutritional value. Secondly, the advancements in the employment of analytical techniques to determine the antioxidant potential through a convenient, easy and fast way are outlined. Such analytical techniques include electron paramagnetic resonance (EPR) and infrared (IR) spectroscopy, electrochemical, and chemometric methods, flow injection analysis (FIA), optical sensors, and high resolution screening (HRS). Taking into consideration that fruits and vegetables are complex mixtures of water- and lipid-soluble antioxidants, the exploitation of chemometrics to develop "omics" platforms (i.e., metabolomics, foodomics) is a promising tool for researchers to decode and/or predict antioxidant activity of fresh produce. For industry, the use of optical sensors and IR spectroscopy is recommended to estimate the antioxidant activity rapidly and at low cost, although legislation does not allow its correlation with health claims. PMID: 29468146 [PubMed]

Related Articles Regulation of ascorbate biosynthesis in green algae has evolved to enable rapid stress-induced response via the VTC2 gene encoding GDP-l-galactose phosphorylase. New Phytol. 2017 Apr;214(2):668-681 Authors: Vidal-Meireles A, Neupert J, Zsigmond L, Rosado-Souza L, Kovács L, Nagy V, Galambos A, Fernie AR, Bock R, Tóth SZ Abstract Ascorbate (vitamin C) plays essential roles in stress resistance, development, signaling, hormone biosynthesis and regulation of gene expression; however, little is known about its biosynthesis in algae. In order to provide experimental proof for the operation of the Smirnoff-Wheeler pathway described for higher plants and to gain more information on the regulation of ascorbate biosynthesis in Chlamydomonas reinhardtii, we targeted the VTC2 gene encoding GDP-l-galactose phosphorylase using artificial microRNAs. Ascorbate concentrations in VTC2 amiRNA lines were reduced to 10% showing that GDP-l-galactose phosphorylase plays a pivotal role in ascorbate biosynthesis. The VTC2 amiRNA lines also grow more slowly, have lower chlorophyll content, and are more susceptible to stress than the control strains. We also demonstrate that: expression of the VTC2 gene is rapidly induced by H2 O2 and 1 O2 resulting in a manifold increase in ascorbate content; in contrast to plants, there is no circadian regulation of ascorbate biosynthesis; photosynthesis is not required per se for ascorbate biosynthesis; and Chlamydomonas VTC2 lacks negative feedback regulation by ascorbate in the physiological concentration range. Our work demonstrates that ascorbate biosynthesis is also highly regulated in Chlamydomonas albeit via mechanisms distinct from those previously described in land plants. PMID: 28112386 [PubMed - indexed for MEDLINE]

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 2018/02/22PubMed comprises more than millions of 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.

20 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 2018/02/21PubMed comprises more than millions of 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.

Related Articles Circulating bile acids in healthy adults respond differently to a dietary pattern characterized by whole grains, legumes and fruits and vegetables compared to a diet high in refined grains and added sugars: a randomized, controlled, crossover feeding study. Metabolism. 2018 Feb 16;: Authors: Ginos BNR, Navarro SL, Schwarz Y, Gu H, Wang D, Randolph TW, Shojaie A, Hullar MAJ, Lampe PD, Kratz M, Neuhouser ML, Raftery D, Lampe JW Abstract OBJECTIVE: The effects of diets high in refined grains on biliary and colonic bile acids have been investigated extensively. However, the effects of diets high in whole versus refined grains on circulating bile acids, which can influence glucose homeostasis and inflammation through activation of farnesoid X receptor (FXR) and G protein-coupled bile acid receptor 1 (TGR5), have not been studied. MATERIALS AND METHODS: We conducted a secondary analysis from a randomized controlled crossover feeding trial (NCT00622661) in 80 healthy adults (40 women/40 men, age 18-45 years) from the greater Seattle Area, half of which were normal weight (BMI 18.5-25.0 kg/m2) and half overweight to obese (BMI 28.0-39.9 kg/m2). Participants consumed two four-week controlled diets in randomized order: 1) a whole grain diet (WG diet), designed to be low in glycemic load (GL), high in whole grains, legumes, and fruits and vegetables, and 2) a refined grain diet (RG diet), designed to be high GL, high in refined grains and added sugars, separated by a four-week washout period. Quantitative targeted analysis of 55 bile acid species in fasting plasma was performed using liquid chromatography tandem mass spectrometry. Concentrations of glucose, insulin, and CRP were measured in fasting serum. Linear mixed models were used to test the effects of diet on bile acid concentrations, and determine the association between plasma bile acid concentrations and HOMA-IR and CRP. Benjamini-Hochberg false discovery rate (FDR) < 0.05 was used to control for multiple testing. RESULTS: A total of 29 plasma bile acids were reliably detected and retained for analysis. Taurolithocholic acid (TLCA), taurocholic acid (TCA) and glycocholic acid (GCA) were statistically significantly higher after the WG compared to the RG diet (FDR < 0.05). There were no significant differences by BMI or sex. When evaluating the association of bile acids and HOMA-IR, GCA, taurochenodeoxycholic acid, ursodeoxycholic acid (UDCA), 5β-cholanic acid-3β,12α-diol, 5-cholanic acid-3β-ol, and glycodeoxycholic acid (GDCA) were statistically significantly positively associated with HOMA-IR individually, and as a group, total, 12α-hydroxylated, primary and secondary bile acids were also significant (FDR < 0.05). When stratifying by BMI, chenodeoxycholic acid (CDCA), cholic acid (CA), UDCA, 5β-cholanic acid-3β, deoxycholic acid, and total, 12α-hydroxylated, primary and secondary bile acid groups were significantly positively associated with HOMA-IR among overweight to obese individuals (FDR <0.05). When stratifying by sex, GCA, CDCA, TCA, CA, UDCA, GDCA, glycolithocholic acid (GLCA), total, primary, 12α-hydroxylated, and glycine-conjugated bile acids were significantly associated with HOMA-IR among women, and CDCA, GDCA, and GLCA were significantly associated among men (FDR < 0.05). There were no significant associations between bile acids and CRP. CONCLUSIONS: Diets with comparable macronutrient and energy composition, but differing in carbohydrate source, affected fasting plasma bile acids differently. Specifically, a diet characterized by whole grains, legumes, and fruits and vegetables compared to a diet high in refined grains and added sugars led to modest increases in concentrations of TLCA, TCA and GCA, ligands for FXR and TGR5, which may have beneficial effects on glucose homeostasis. PMID: 29458053 [PubMed - as supplied by publisher]

Related Articles A Multi-Omics Analysis of Glycine max Leaves Reveals Alteration in Flavonoid and Isoflavonoid Metabolism upon Ethylene and Abscisic acid Treatment. Proteomics. 2018 Feb 19;: Authors: Gupta R, Min CW, Kramer K, Agrawal GK, Rakwal R, Park KH, Wang Y, Finkemeier I, Kim ST Abstract Phytohormones are central to the plant growth and development. Despite the advancement in our knowledge of hormone signaling, downstream targets and their interactions upon hormones action remain largely fragmented, especially at the protein and metabolite levels. With an aim to get new insight into the effects of two hormones, ethylene (ET) and abscisic acid (ABA), this study utilizes an integrated proteomics and metabolomics approach to investigate their individual and combined (ABA+ET) signaling in soybean leaves. Targeting low-abundance proteins, our previously established protamine sulfate precipitation method was applied, followed by label-free quantification of identified proteins. A total of 4129 unique protein groups including 1083 differentially modulated in one (individual) or other (combined) treatments were discerned. Functional annotation of the identified proteins showed an increased abundance of proteins related to the flavonoid and isoflavonoids biosynthesis and MAPK-signaling pathway in response to ET treatment. HPLC analysis showed an accumulation of isoflavones (genistin, daidzein, and genistein) upon ET treatment, in agreement with the proteomics results. A metabolome analysis assigned 79 metabolites and further confirmed the accumulation of flavonoids and isoflavonoids in response to ET. A potential cross-talk between ET and MAPK-signaling, leading to the accumulation of flavonoids and isoflavonoids in soybean leaves is suggested. This article is protected by copyright. All rights reserved. PMID: 29457974 [PubMed - as supplied by publisher]