Integrative Molecular Phenotyping
INTEGRATIVE MOLECULAR
PHENOTYPING
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY
DEPARTMENT OF MEDICAL
BIOCHEMISTRY AND BIOPHYSICS
WHEELOCK LABORATORY

PubMed

Bile salt stabilized vesicles (bilosomes): A novel nano-pharmaceutical design for oral delivery of Proteins and Peptides.

Thu, 26/01/2017 - 14:00
Bile salt stabilized vesicles (bilosomes): A novel nano-pharmaceutical design for oral delivery of Proteins and Peptides. Curr Pharm Des. 2017 Jan 24; Authors: Ahmad J, Singhal M, Amin S, Rizwanullah M, Akhter S, Kamal MA, Haider N, Midoux P, Pichon C Abstract With the advent of novel vesicular drug delivery systems especially bilosomes, for large molecular weight proteins and peptides, their oral administration seems a viable approach. These nano-vesicles have shown promising results for the effective delivery of insulin and other therapeutics, perhaps due to their structural composition. The present review has elaborated the biopharmaceutical challenges for the oral delivery of therapeutic proteins and peptides as well as presented a novel approach to deliver the essential macromolecules through oral route as bilosomes. The extensive search has been presented related to the formulation, evaluation and in vivo performance of bilosomes. Some of the crucial findings related to bilosomes have corroborated them superior to other colloidal carriers. The successful drug delivery through bilosomes requires significant justifications related to their interaction with the biological membranes. The other aspects such as absolute absorption, safety and toxicity of bilosome drug delivery should also be equally considered. PMID: 28120725 [PubMed - as supplied by publisher]

A Quantitative Profiling Method of Phytohormones and Other Metabolites Applied to Barley Roots Subjected to Salinity Stress.

Thu, 26/01/2017 - 14:00
Related Articles A Quantitative Profiling Method of Phytohormones and Other Metabolites Applied to Barley Roots Subjected to Salinity Stress. Front Plant Sci. 2016;7:2070 Authors: Cao D, Lutz A, Hill CB, Callahan DL, Roessner U Abstract As integral parts of plant signaling networks, phytohormones are involved in the regulation of plant metabolism and growth under adverse environmental conditions, including salinity. Globally, salinity is one of the most severe abiotic stressors with an estimated 800 million hectares of arable land affected. Roots are the first plant organ to sense salinity in the soil, and are the initial site of sodium (Na(+)) exposure. However, the quantification of phytohormones in roots is challenging, as they are often present at extremely low levels compared to other plant tissues. To overcome this challenge, we developed a high-throughput LC-MS method to quantify ten endogenous phytohormones and their metabolites of diverse chemical classes in roots of barley. This method was validated in a salinity stress experiment with six barley varieties grown hydroponically with and without salinity. In addition to phytohormones, we quantified 52 polar primary metabolites, including some phytohormone precursors, using established GC-MS and LC-MS methods. Phytohormone and metabolite data were correlated with physiological measurements including biomass, plant size and chlorophyll content. Root and leaf elemental analysis was performed to determine Na(+) exclusion and K(+) retention ability in the studied barley varieties. We identified distinct phytohormone and metabolite signatures as a response to salinity stress in different barley varieties. Abscisic acid increased in the roots of all varieties under salinity stress, and elevated root salicylic acid levels were associated with an increase in leaf chlorophyll content. Furthermore, the landrace Sahara maintained better growth, had lower Na(+) levels and maintained high levels of the salinity stress linked metabolite putrescine as well as the phytohormone metabolite cinnamic acid, which has been shown to increase putrescine concentrations in previous studies. This study highlights the importance of root phytohormones under salinity stress and the multi-variety analysis provides an important update to analytical methodology, and adds to the current knowledge of salinity stress responses in plants at the molecular level. PMID: 28119732 [PubMed - in process]

Agrimonolide and Desmethylagrimonolide Induced HO-1 Expression in HepG2 Cells through Nrf2-Transduction and p38 Inactivation.

Thu, 26/01/2017 - 14:00
Related Articles Agrimonolide and Desmethylagrimonolide Induced HO-1 Expression in HepG2 Cells through Nrf2-Transduction and p38 Inactivation. Front Pharmacol. 2016;7:513 Authors: Chen L, Teng H, Zhang KY, Skalicka-Woźniak K, Georgiev MI, Xiao J Abstract Agrimonolide and desmethylagrimonolide are the main bioactive polyphenols in agrimony with well-documented antioxidant, anti-diabetic, and anti-inflammatory potential. We report here for the first time that agrimonolide and desmethylagrimonolide stimulate the expression of phase II detoxifying enzymes through the Nrf2-dependent signaling pathway. Agrimonolide and desmethylagrimonolide also possess considerable protective activity from oxidative DNA damage. In order to explore the cytoprotective potential of agrimonolide and desmethylagrimonolide on oxidative stress in liver, we developed an oxidative stress model in HepG2 cells, and check the hypothesis whether Nrf2 pathway is involved. Western blotting and luciferase assay revealed that exposure of HepG2 cells to agrimonolide or desmethylagrimonolide leads to increased heme oxygenase-1 (HO-1) expression by activating ARE through induction of Nrf2 and suppression of Kelch-like ECH-associated protein 1 (Keap1). Moreover, agrimonolide and desmethylagrimonolide also activated ERK signaling pathways and significantly attenuated individual p38 MAPK expression, subsequently leading to Nrf2 nuclear translocation. In conclusion, our results indicated that transcriptional activation of Nrf2/ARE is critical in agrimonolide and desmethylagrimonolide-mediated HO-1 induction, which can be regulated partially by the blockade of p38 MAPK signaling pathway and inhibiting nuclear translocation of Nrf2. PMID: 28119605 [PubMed - in process]

Increased Dynamics of Tricarboxylic Acid Cycle and Glutamate Synthesis in Obese Adipose Tissue: In vivo Metabolic Turnover Analysis.

Thu, 26/01/2017 - 14:00
Related Articles Increased Dynamics of Tricarboxylic Acid Cycle and Glutamate Synthesis in Obese Adipose Tissue: In vivo Metabolic Turnover Analysis. J Biol Chem. 2017 Jan 24;: Authors: Nagao H, Nishizawa H, Bamba T, Nakayama Y, Isozumi N, Nagamori S, Kanai Y, Tanaka Y, Kita S, Fukuda S, Funahashi T, Maeda N, Fukusaki E, Shimomura I Abstract Obesity locates upstream of various metabolic disorders. However, little is known about abnormalities in metabolic change of obese adipose tissue. Here, we use static metabolic analysis and in vivo metabolic turn over analysis to assess metabolic dynamics in obese mice. The static metabolic analyses showed that glutamate and constitutive metabolites of tricarboxylic acid (TCA) cycle were increased in white adipose tissue (WAT) of ob/ob and diet-induced obesity (DIO) mice, but not in liver or skeletal muscle of these obese mice. Moreover, in vivo metabolic turnover analyses demonstrated that glucose-derived these metabolites were dynamically and specifically produced in obese WAT, compared to lean WAT. Glutamate rise in obese WAT was associated with downregulation of GLAST, a major glutamate transporter for adipocytes, and low uptake of glutamate into adipose tissue. In adipocytes, glutamate treatment reduced adiponectin secretion and insulin-mediated glucose uptake and phosphorylation of Akt. These data suggest that high intra-adipocytes glutamate level potentially relates to adipocyte dysfunction in obesity. The study provides novel insight of metabolic dysfunction in obesity through comprehensive application of in vivo metabolic turnover analysis in two obese animal models. PMID: 28119455 [PubMed - as supplied by publisher]

METabolic Syndrome In Men (METSIM) Study: a resource for studies of metabolic and cardiovascular diseases.

Thu, 26/01/2017 - 14:00
Related Articles METabolic Syndrome In Men (METSIM) Study: a resource for studies of metabolic and cardiovascular diseases. J Lipid Res. 2017 Jan 24;: Authors: Laakso M, Kuusisto J, Stancakova A, Kuulasmaa T, Pajukanta P, Lusis AJ, Collins FS, Mohlke K, Boehnke M Abstract METabolic Syndrome In Men (METSIM) study is a population-based study including 10,197 Finnish men examined in 2005-2010. The aim of the study is to investigate non-genetic and genetic factors associated with the risk of type 2 diabetes and cardiovascular disease, and with cardiovascular risk factors. The protocol includes a detailed phenotyping of the participants, an oral glucose tolerance test, fasting laboratory measurements including proton nuclear magnetic resonance measurements, mass spectometry metabolomics, adipose tissue biopsies from 1,400 participants, and a stool sample. In our ongoing follow-up study, we have to date re-examined 6,496 participants. Extensive genotyping and exome sequencing have been performed for essentially all METSIM participants, and >2,000 METSIM participants have been whole genome sequenced. We have identified several non-genetic markers associated with the development of diabetes and cardiovascular events, and participated in several genetic association studies to identify gene variants associated with diabetes, hyperglycemia and cardiovascular risk factors. The generation of a phenotype and genotype resource in the METSIM study allows us to proceed towards "systems genetics" approach which includes statistical methods to quantitate and integrate intermediate phenotypes, such as transcript, protein or metabolite levels to provide a global view of the molecular architecture of complex traits. PMID: 28119442 [PubMed - as supplied by publisher]

Feasibility of ultra-performance liquid chromatography-ion mobility-time-of-flight mass spectrometry in analyzing oxysterols.

Thu, 26/01/2017 - 14:00
Related Articles Feasibility of ultra-performance liquid chromatography-ion mobility-time-of-flight mass spectrometry in analyzing oxysterols. J Chromatogr A. 2017 Jan 18;: Authors: Kylli P, Hankemeier T, Kostiainen R Abstract Oxysterols are oxygenated cholesterols that are important in many cell functions and they may also be indicative of certain diseases. The purpose of this work was to study the feasibility of ultra-performance liquid chromatography-ion mobility-time-of-flight mass spectrometry (UPLC-IM-TOFMS) using traveling wave cell in analyzing oxysterols and especially their isomers in biological samples. Oxysterols were analyzed as their p-toluenesulfonyl isocyanate derivatives, which improved the separation of isomeric oxysterols by ion mobility and ionization efficiency in the electrospray ionization step. The UPLC-IM-TOFMS method was shown to be fast and to provide good quantitative performance. The feasibility of the method was demonstrated in the analyses of oxysterols in fibroblast cell samples. PMID: 28118975 [PubMed - as supplied by publisher]

Chronic unpredictive mild stress leads to altered hepatic metabolic profile and gene expression.

Thu, 26/01/2017 - 14:00
Related Articles Chronic unpredictive mild stress leads to altered hepatic metabolic profile and gene expression. Sci Rep. 2016 Mar 23;6:23441 Authors: Jia HM, Li Q, Zhou C, Yu M, Yang Y, Zhang HW, Ding G, Shang H, Zou ZM Abstract Depression is a complex disease characterized by a series of pathological changes. Research on depression is mainly focused on the changes in brain, but not on liver. Therefore, we initially explored the metabolic profiles of hepatic extracts from rats treated with chronic unpredictive mild stress (CUMS) by UPLC-Q-TOF/MS. Using multivariate statistical analysis, a total of 26 altered metabolites distinguishing CUMS-induced depression from normal control were identified. Using two-stage receiver operating characteristic (ROC) analysis, 18 metabolites were recognized as potential biomarkers related to CUMS-induced depression via 12 metabolic pathways. Subsequently, we detected the mRNA expressions levels of apoptosis-associated genes such as Bax and Bcl-2 and four key enzymes including Pla2g15, Pnpla6, Baat and Gad1 involved in phospholipid and primary bile acid biosynthesis in liver tissues of CUMS rats by real-time qRT-PCR assay. The expression levels of Bax, Bcl-2, Pla2g15, Pnpla6 and Gad1 mRNA were 1.43,1.68, 1.74, 1.67 and 1.42-fold higher, and those of Baat, Bax/Bcl-2 ratio mRNA were 0.83, 0.85-fold lower in CUMS rats compared with normal control. Results of liver-targeted metabonomics and mRNA expression demonstrated that CUMS-induced depression leads to variations in hepatic metabolic profile and gene expression, and ultimately results in liver injury. PMID: 27006086 [PubMed - indexed for MEDLINE]

metabolomics; +17 new citations

Wed, 25/01/2017 - 13:14
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 2017/01/25PubMed 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.

How close are we to complete annotation of metabolomes?

Tue, 24/01/2017 - 12:31
How close are we to complete annotation of metabolomes? Curr Opin Chem Biol. 2017 Jan 20;36:64-69 Authors: Viant MR, Kurland IJ, Jones MR, Dunn WB Abstract The metabolome describes the full complement of the tens to hundreds of thousands of low molecular weight metabolites present within a biological system. Identification of the metabolome is critical for discovering the maximum amount of biochemical knowledge from metabolomics datasets. Yet no exhaustive experimental characterisation of any organismal metabolome has been reported to date, dramatically contrasting with the genome sequencing of thousands of plants, animals and microbes. Here, we review the status of metabolome annotation and describe advances in the analytical methodologies being applied. In part through new international coordination, we conclude that we are now entering a new era of metabolome annotation. PMID: 28113135 [PubMed - as supplied by publisher]

Inference of cancer mechanisms through computational systems analysis.

Tue, 24/01/2017 - 12:31
Inference of cancer mechanisms through computational systems analysis. Mol Biosyst. 2017 Jan 23;: Authors: Qi Z, Voit EO Abstract Large amounts of metabolomics data have been accumulated to study metabolic alterations in cancer that allow cancer cells to synthesize molecular materials necessary for cell growth and proliferation. Although metabolic reprogramming in cancer was discovered almost a century ago, the underlying biochemical mechanisms are still unclear. We show that metabolomics data can be used to infer likely biochemical mechanisms associated with cancer. The proposed inference method is data-driven and quite generic; its efficacy is demonstrated by the analysis of changes in purine metabolism of human renal cell carcinoma. The method and results are essentially unbiased and tolerate noise in the data well. The proposed method correctly identified and accurately quantified primary enzymatic alterations in cancer, and these account for over 80% of the metabolic alterations in the investigated carcinoma. Interestingly, the two primary action sites are not the most sensitive reaction steps in purine metabolism, which implies that sensitivity analysis is not a valid approach for identifying cancer targets. The proposed method exhibits statistically high precision and robustness even for analyses of moderately incomplete metabolomics data. By permitting analyses of individual metabolic profiles, the method may become a tool of personalized precision medicine. PMID: 28112324 [PubMed - as supplied by publisher]

Multi-omics analyses reveal metabolic alterations regulated by hepatitis B virus core protein in hepatocellular carcinoma cells.

Tue, 24/01/2017 - 12:31
Multi-omics analyses reveal metabolic alterations regulated by hepatitis B virus core protein in hepatocellular carcinoma cells. Sci Rep. 2017 Jan 23;7:41089 Authors: Xie Q, Fan F, Wei W, Liu Y, Xu Z, Zhai L, Qi Y, Ye B, Zhang Y, Basu S, Zhao Z, Wu J, Xu P Abstract Chronic hepatitis B virus (HBV) infection is partly responsible for hepatitis, fatty liver disease and hepatocellular carcinoma (HCC). HBV core protein (HBc), encoded by the HBV genome, may play a significant role in HBV life cycle. However, the function of HBc in the occurrence and development of liver disease is still unclear. To investigate the underlying mechanisms, HBc-transfected HCC cells were characterized by multi-omics analyses. Combining proteomics and metabolomics analyses, our results showed that HBc promoted the expression of metabolic enzymes and the secretion of metabolites in HCC cells. In addition, glycolysis and amino acid metabolism were significantly up-regulated by HBc. Moreover, Max-like protein X (MLX) might be recruited and enriched by HBc in the nucleus to regulate glycolysis pathways. This study provides further insights into the function of HBc in the molecular pathogenesis of HBV-induced diseases and indicates that metabolic reprogramming appears to be a hallmark of HBc transfection. PMID: 28112229 [PubMed - in process]

Loss of Merlin induces metabolomic adaptation that engages dependence on Hedgehog signaling.

Tue, 24/01/2017 - 12:31
Loss of Merlin induces metabolomic adaptation that engages dependence on Hedgehog signaling. Sci Rep. 2017 Jan 23;7:40773 Authors: Das S, Jackson WP, Prasain JK, Hanna A, Bailey SK, Tucker JA, Bae S, Wilson LS, Samant RS, Barnes S, Shevde LA Abstract The tumor suppressor protein Merlin is proteasomally degraded in breast cancer. We undertook an untargeted metabolomics approach to discern the global metabolomics profile impacted by Merlin in breast cancer cells. We discerned specific changes in glutathione metabolites that uncovered novel facets of Merlin in impacting the cancer cell metabolome. Concordantly, Merlin loss increased oxidative stress causing aberrant activation of Hedgehog signaling. Abrogation of GLI-mediated transcription activity compromised the aggressive phenotype of Merlin-deficient cells indicating a clear dependence of cells on Hedgehog signaling. In breast tumor tissues, GLI1 expression enhanced tissue identification and discriminatory power of Merlin, cumulatively presenting a powerful substantiation of the relationship between these two proteins. We have uncovered, for the first time, details of the tumor cell metabolomic portrait modulated by Merlin, leading to activation of Hedgehog signaling. Importantly, inhibition of Hedgehog signaling offers an avenue to target the vulnerability of tumor cells with loss of Merlin. PMID: 28112165 [PubMed - in process]

Genetics of schizophrenia: A consensus paper of the WFSBP Task Force on Genetics.

Tue, 24/01/2017 - 12:31
Genetics of schizophrenia: A consensus paper of the WFSBP Task Force on Genetics. World J Biol Psychiatry. 2017 Jan 23;:1-14 Authors: Giegling I, Hosak L, Mössner R, Serretti A, Bellivier F, Claes S, Collier DA, Corrales A, DeLisi LE, Gallo C, Gill M, Kennedy JL, Leboyer M, Maier W, Marquez M, Massat I, Mors O, Muglia P, Nöthen MM, Ospina-Duque J, Owen MJ, Propping P, Shi Y, St Clair D, Thibaut F, Cichon S, Mendlewicz J, O'Donovan MC, Rujescu D Abstract OBJECTIVES: Schizophrenia is a severe psychiatric disease affecting about 1% of the general population. The relative contribution of genetic factors has been estimated to be up to 80%. The mode of inheritance is complex, non-Mendelian, and in most cases involving the combined action of large numbers of genes. METHODS: This review summarises recent efforts to identify genetic variants associated with schizophrenia detected, e.g., through genome-wide association studies, studies on copy-number variants or next-generation sequencing. RESULTS: A large, new body of evidence on genetics of schizophrenia has accumulated over recent years. Many new robustly associated genetic loci have been detected. Furthermore, there is consensus that at least a dozen microdeletions and microduplications contribute to the disease. Genetic overlap between schizophrenia, other psychiatric disorders, and neurodevelopmental syndromes raised new questions regarding the current classification of psychiatric and neurodevelopmental diseases. CONCLUSIONS: Future studies will address especially the functional characterisation of genetic variants. This will hopefully open the doors to our understanding of the pathophysiology of schizophrenia and other related diseases. Complementary, integrated systems biology approaches to genomics, transcriptomics, proteomics and metabolomics may also play crucial roles in enabling a precision medicine approach to the treatment of individual patients. PMID: 28112043 [PubMed - as supplied by publisher]

Systematic evaluation of serum and plasma collection on the endogenous metabolome.

Tue, 24/01/2017 - 12:31
Systematic evaluation of serum and plasma collection on the endogenous metabolome. Bioanalysis. 2017 Jan 23;: Authors: Zhou Z, Chen Y, He J, Xu J, Zhang R, Mao Y, Abliz Z Abstract AIM: In metabolomics research, the use of different blood collection methods may influence endogenous metabolites. MATERIALS & METHODS: Ultra HPLC coupled with MS/MS was applied together with multivariate statistics to investigate metabolomics differences in serum and plasma samples handled by different anticoagulants. A total of 135 known representative metabolites were assessed for comprehensive evaluation of the effects of anticoagulants. RESULTS: Exogenous factors, including separation gel ingredients from the serum collection tubes and the anticoagulants, affected mass spectrometer detection. Heparin plasma yielded the best detection of different functional groups and is therefore the optimal blood specimen for metabolomics research, followed by potassium oxalate plasma. PMID: 28111959 [PubMed - as supplied by publisher]

Ultra high performance liquid chromatography-high resolution mass spectrometry plasma lipidomics can distinguish between canine breeds despite uncontrolled environmental variability and non-standardized diets.

Tue, 24/01/2017 - 12:31
Related Articles Ultra high performance liquid chromatography-high resolution mass spectrometry plasma lipidomics can distinguish between canine breeds despite uncontrolled environmental variability and non-standardized diets. Metabolomics. 2017;13(2):15 Authors: Lloyd AJ, Beckmann M, Wilson T, Tailliart K, Allaway D, Draper J Abstract INTRODUCTION AND OBJECTIVES: The purpose of this study was to use high accurate mass metabolomic profiling to investigate differences within a phenotypically diverse canine population, with breed-related morphological, physiological and behavioural differences. Previously, using a broad metabolite fingerprinting approach, lipids appear to dominate inter- and intra- breed discrimination. The purpose here was to use Ultra High Performance Liquid Chromatography-High Resolution Mass Spectrometry (UHPLC-HRMS) to identify in more detail, inter-breed signatures in plasma lipidomic profiles of home-based, client-owned dogs maintained on different diets and fed according to their owners' feeding regimens. METHODS: Nine dog breeds were recruited in this study (Beagle, Chihuahua, Cocker Spaniel, Dachshund, Golden Retriever, Greyhound, German Shepherd, Labrador Retriever and Maltese: 7-12 dogs per breed). Metabolite profiling on a MTBE lipid extract of fasted plasma was performed using UHPLC-HRMS. RESULTS: Multivariate modelling and classification indicated that the main source of lipidome variance was between the three breeds Chihuahua, Dachshund and Greyhound and the other six breeds, however some intra-breed variance was evident in Labrador Retrievers. Metabolites associated with dietary intake impacted on breed-associated variance and following filtering of these signals out of the data-set unique inter-breed lipidome differences for Chihuahua, Golden Retriever and Greyhound were identified. CONCLUSION: By using a phenotypically diverse home-based canine population, we were able to show that high accurate mass lipidomics can enable identification of metabolites in the first pass plasma profile, capturing distinct metabolomic variability associated with genetic differences, despite environmental and dietary variability. PMID: 28111530 [PubMed - in process]

NMR Techniques in Metabolomic Studies: A Quick Overview on Examples of Utilization.

Tue, 24/01/2017 - 12:31
Related Articles NMR Techniques in Metabolomic Studies: A Quick Overview on Examples of Utilization. Appl Magn Reson. 2017;48(1):1-21 Authors: Kruk J, Doskocz M, Jodłowska E, Zacharzewska A, Łakomiec J, Czaja K, Kujawski J Abstract Metabolomics is a rapidly developing branch of science that concentrates on identifying biologically active molecules with potential biomarker properties. To define the best biomarkers for diseases, metabolomics uses both models (in vitro, animals) and human, as well as, various techniques such as mass spectroscopy, gas chromatography, liquid chromatography, infrared and UV-VIS spectroscopy and nuclear magnetic resonance. The last one takes advantage of the magnetic properties of certain nuclei, such as (1)H, (13)C, (31)P, (19)F, especially their ability to absorb and emit energy, what is crucial for analyzing samples. Among many spectroscopic NMR techniques not only one-dimensional (1D) techniques are known, but for many years two-dimensional (2D, for example, COSY, DOSY, JRES, HETCORE, HMQS), three-dimensional (3D, DART-MS, HRMAS, HSQC, HMBC) and solid-state NMR have been used. In this paper, authors taking apart fundamental division of nuclear magnetic resonance techniques intend to shown their wide application in metabolomic studies, especially in identifying biomarkers. PMID: 28111499 [PubMed - in process]

GC-MS-based Metabolomics Identifies an Amino Acid Signature of Acute Ischemic Stroke.

Tue, 24/01/2017 - 12:31
Related Articles GC-MS-based Metabolomics Identifies an Amino Acid Signature of Acute Ischemic Stroke. Neurosci Lett. 2017 Jan 19;: Authors: Wang D, Kong J, Wu J, Wang X, Lai M Abstract Ischemic stroke is a serious public health problem worldwide. Here, we characterized the metabolite features of acute ischemic stroke (AIS) using a gas chromatography-mass spectrometry-based metabolomics. Forty AIS patients and 29 sex and age-matched controls were recruited. The serum metabolic profiles were significantly different between the two groups. Compared to the controls, the patients had elevated levels of lactate, carbonate and glutamate (P<0.01), and lowered levels of alanine, citrate, glycine, isoleucine, leucine, serine, tyrosine, methionine, tryptophan, erythronic acid, urea, purine, hypoxanthine, and proline in the serum (P<0.05). Amino acids are the most important disturbed metabolites. Most dysregulated metabolites are closely correlated with each other and with several biochemical indices. The differential metabolites reflect pathophysiological processes of inflammation, energy deficit, oxidative stress, neurotoxicity, neuro excitation and injury. Tyrosine, lactate, and tryptophan were screened as a panel of potential biomarkers of AIS, jointly enabling a high precision (91.7%) to diagnose AIS by classification and regression tree (CRT). Collectively, we discovered a marked perturbation of metabolome of AIS in the serum, mainly associated with amino acid-related metabolism. Tyrosine, lactate, and tryptophan may be considered as potential biomarkers of AIS. PMID: 28111353 [PubMed - as supplied by publisher]

The Application of Principal Component Analysis to Drug Discovery and Biomedical Data.

Tue, 24/01/2017 - 12:31
Related Articles The Application of Principal Component Analysis to Drug Discovery and Biomedical Data. Drug Discov Today. 2017 Jan 19;: Authors: Giuliani A Abstract There is a neat distinction between general purpose statistical techniques and quantitative models developed for specific problems .Principal Component Analysis (PCA) blurs this distinction: while being a general purpose statistical technique, it implies a peculiar style of reasoning. PCA is a 'hypothesis generating' tool creating a statistical mechanics frame for biological systems modeling without the need for strong a priori theoretical assumptions. This makes PCA of utmost importance for approaching drug discovery by a systemic perspective overcoming too narrow reductionist approaches. PMID: 28111329 [PubMed - as supplied by publisher]

Metabolomic profiling of brain tissues of mice chronically exposed to heroin.

Tue, 24/01/2017 - 12:31
Related Articles Metabolomic profiling of brain tissues of mice chronically exposed to heroin. Drug Metab Pharmacokinet. 2016 Oct 27;: Authors: Li RS, Takeda T, Ohshima T, Yamada H, Ishii Y Abstract The chronic neurotoxicity of heroin on the nervous system is poorly understood. To address this issue, we comprehensively assessed the alteration of brain metabolomics caused by chronic heroin exposure and the withdrawal of heroin. Male C57BL/6J mice (n = 10) were given heroin (15 μmol/kg, i.p., twice a day) for 12 days while the withdrawal group received saline-treatment instead of heroin for the last two days. The control group received saline. We developed an UPLC-TOF/MS-based metabolomic approach to analyze the metabolites and carry out a metabolic pathway analysis in the brain. The major metabolites contributing to the discrimination were identified as amino acids, tricarboxylic-acid cycle intermediates, neurotransmitters, nucleotides and other compounds. A marked reduction in histidine and a slight but significant increase in phenylalanine and tryptophan were observed after heroin was withdrawn while the increased level of catecholamines was restored to baseline. Interestingly, N-acetylserotonin - a precursor of melatonin - was increased with the withdrawal of heroin while melatonin was markedly reduced along with the sub-chronic exposure to heroin. This shows that heroin disrupts not only the energy metabolism but also the biosynthesis of both catecholamines and melatonin in the mouse brain. Therefore, these substances are candidate biomarkers for chronic heroin-abuse. PMID: 28111102 [PubMed - as supplied by publisher]

Carbon Sources Tune Antibiotic Susceptibility in Pseudomonas aeruginosa via Tricarboxylic Acid Cycle Control.

Tue, 24/01/2017 - 12:31
Related Articles Carbon Sources Tune Antibiotic Susceptibility in Pseudomonas aeruginosa via Tricarboxylic Acid Cycle Control. Cell Chem Biol. 2017 Jan 16;: Authors: Meylan S, Porter CB, Yang JH, Belenky P, Gutierrez A, Lobritz MA, Park J, Kim SH, Moskowitz SM, Collins JJ Abstract Metabolically dormant bacteria present a critical challenge to effective antimicrobial therapy because these bacteria are genetically susceptible to antibiotic treatment but phenotypically tolerant. Such tolerance has been attributed to impaired drug uptake, which can be reversed by metabolic stimulation. Here, we evaluate the effects of central carbon metabolite stimulations on aminoglycoside sensitivity in the pathogen Pseudomonas aeruginosa. We identify fumarate as a tobramycin potentiator that activates cellular respiration and generates a proton motive force by stimulating the tricarboxylic acid (TCA) cycle. In contrast, we find that glyoxylate induces phenotypic tolerance by inhibiting cellular respiration with acetyl-coenzyme A diversion through the glyoxylate shunt, despite drug import. Collectively, this work demonstrates that TCA cycle activity is important for both aminoglycoside uptake and downstream lethality and identifies a potential strategy for potentiating aminoglycoside treatment of P. aeruginosa infections. PMID: 28111098 [PubMed - as supplied by publisher]

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