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

Exploiting plug-and-play electrochemistry for drug discovery.

Thu, 20/07/2017 - 04:57
Related Articles Exploiting plug-and-play electrochemistry for drug discovery. Future Med Chem. 2016 Apr;8(5):567-77 Authors: Gao L, Teng Y Abstract Electrochemistry has emerged as a powerful analytical technique for chemical analysis of living cells, biologically active molecules and metabolites. Electrochemical biosensor, microfluidics and mass spectrometry are the most frequently used methods for electrochemical detection and monitory, which comprise a collection of extremely useful measurement tools for various fields of biology and medicine. Most recently, electrochemistry has been shown to be coupled with nanotechnology and genetic engineering to generate new enabling technologies, providing rapid, selective, and sensitive detection and diagnosis platforms. The primary focus of this review is to highlight the utility of electrochemical strategies and their conjunction with other approaches for drug metabolism and discovery. Current challenges and possible future developments and applications of electrochemistry in drug studies are also discussed. PMID: 27079543 [PubMed - indexed for MEDLINE]

metabolomics; +18 new citations

Tue, 18/07/2017 - 13:21
18 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 2017/07/18PubMed 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.

Grapevine tissues and phenology differentially affect soluble carbohydrates determination by capillary electrophoresis.

Mon, 17/07/2017 - 12:55
Grapevine tissues and phenology differentially affect soluble carbohydrates determination by capillary electrophoresis. Plant Physiol Biochem. 2017 Jul 08;118:394-399 Authors: Moreno D, Berli F, Bottini R, Piccoli PN, Silva MF Abstract Soluble carbohydrates distribution depends on plant physiology and, among other important factors, determines fruit yield and quality. In plant biology, the analysis of sugars is useful for many purposes, including metabolic studies. Capillary electrophoresis (CE) proved to be a powerful green separation technique with minimal sample preparation, even in complex plant tissues, that can provide high-resolution efficiency. Matrix effect refers to alterations in the analytical response caused by components of a sample other than the analyte of interest. Thus, the assessment and reduction of the matrix factor is fundamental for metabolic studies in different matrices. The present study evaluated the source and levels of matrix effects in the determination of most abundant sugars in grapevine tissues (mature and young leaves, berries and roots) at two phenological growth stages. Sucrose was the sugar that showed the least matrix effects, while fructose was the most affected analyte. Based on plant tissues, young leaves presented the smaller matrix effects, irrespectively of the phenology. These changes may be attributed to considerable differences at chemical composition of grapevine tissues with plant development. Therefore, matrix effect should be an important concern for plant metabolomics. PMID: 28711788 [PubMed - as supplied by publisher]

The human microbiome.

Mon, 17/07/2017 - 12:55
The human microbiome. Adv Med Sci. 2017 Jul 13;62(2):414-420 Authors: Blum HE Abstract Until recently, human microbiology was based on the identification of single microbes, such as bacteria, fungi and viruses, frequently isolated from patients with acute or chronic infections. Novel culture-independent molecular biochemical analyses (genomics, transcriptomics, proteomics, metabolomics) allow today to detect and classify the diverse microorganisms in a given ecosystem (microbiota), such as the gastrointestinal tract, the skin, the airway system, the urogenital tract and others, and to assess all genomes in these ecosystems (microbiome) as well as their gene products. These analyses revealed that each individual has its own microbiota that plays a role in health and disease. In addition, they greatly contributed to the recent advances in the understanding of the pathogenesis of a wide range of human diseases. It is to be expected that these new insights will translate into diagnostic, therapeutic and preventive measures in the context of personalized/precision medicine. PMID: 28711782 [PubMed - as supplied by publisher]

Metabolomic profiling reveals potential biomarkers in esophageal cancer progression using liquid chromatography-mass spectrometry platform.

Mon, 17/07/2017 - 12:55
Metabolomic profiling reveals potential biomarkers in esophageal cancer progression using liquid chromatography-mass spectrometry platform. Biochem Biophys Res Commun. 2017 Jul 12;: Authors: Zhang H, Wang L, Hou Z, Ma H, Mamtimin B, Hasim A, Sheyhidin I Abstract Esophageal cancer (EC) is one of the most common malignancies with poor prognosis. Metabolomics has been shown to be a powerful approach to discover the potential biomarkers for cancer diagnosis and prognosis. The goal of this study is to screen potential biomarkers for early diagnosis and prognosis. In this study, 40 tissue samples and the corresponding control samples from the same esophageal squamous cell carcinoma (ESCC) patients were analyzed by liquid chromatography-mass spectrometry (LC-MS)-based metabolomics. 20 potential diagnostic biomarkers were selected. Moreover, 9 metabolites were found to be closely correlated with the pathological feature such as local invasion, lymphatic metastasis and postoperative survival time. Glutamate was correlated with local invasion of tumor, and oleic acid, LysoPC(15:0), uracil, inosine and choline were closely related with the lymphatic metastasis, while glutamine, kynurenine, serine and uracil were related with postoperative survival time. The results indicated that the potential biomarkers discovered by metabolomics could reflect the metabolic characterization of ESCC, and offers a novel approach for early diagnosis, assessment and prognosis of the disease. PMID: 28711496 [PubMed - as supplied by publisher]

Ligustrazine modulates renal cysteine biosynthesis in rats exposed to cadmium.

Sun, 16/07/2017 - 14:26
Ligustrazine modulates renal cysteine biosynthesis in rats exposed to cadmium. Environ Toxicol Pharmacol. 2017 Jul 09;54:125-132 Authors: Kuang W, Zhang X, Zhu W, Lan Z Abstract The objective of this study was to determine the effect of ligustrazine (TMP) on cadmium (Cd)-induced nephrotoxicity and its relevant mechanism. TMP (50mg/kg) was injected intraperitoneally (i.p.) into rats 1h prior to CdCl2 exposure (at a Cd dose of 0.6mg/kg). TMP reversed Cd-induced nephrotoxicity, evidenced by the relatively normal architecture of the renal cortex. Additionally, TMP alleviated renal oxidative stress of rats that were exposed to Cd, evidenced by the decreased levels of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), elevated levels of glutathione (GSH) and GSH/GSSG (glutathione disulfide) ratios. Furthermore, TMP also raised the decreased levels of S-adenosylmethionine (SAM) and cystathionine involved in cysteine biosynthesis in rats exposed to Cd. Further analysis revealed that TMP treatment upregulated expression of several proteins involved in cysteine biosynthesis including methionine adenosyltransferases (MATs) and cystathionine-beta-synthase (CBS). Taken together, these results suggest that TMP remodeled metabolomics of cysteine biosynthesis in rat kidneys and attenuated Cd-induced nephrotoxicity. PMID: 28710931 [PubMed - as supplied by publisher]

ROS Mediated Selection for Increased NADPH Availability in Escherichia coli.

Sun, 16/07/2017 - 14:26
ROS Mediated Selection for Increased NADPH Availability in Escherichia coli. Biotechnol Bioeng. 2017 Jul 15;: Authors: Steele Reynolds T, Courtney CM, Erickson KE, Wolfe LM, Chatterjee A, Nagpal P, Gill RT Abstract The economical production of chemicals and fuels by microbial processes remains an intense area of interest in biotechnology. A key limitation in such efforts concerns the availability of key co-factors, in this case NADPH, required for target pathways. Many of the strategies pursued for increasing NADPH availability in Escherichia coli involve manipulations to the central metabolism, which can create redox imbalances and overall growth defects. In this study we used a reactive oxygen species based selection to search for novel methods of increasing NADPH availability. We report a loss of function mutation in the gene hdfR appears to increase NADPH availability in E. coli. Additionally, we show this excess NADPH can be used to improve the production of 3HP in E. coli. This article is protected by copyright. All rights reserved. PMID: 28710857 [PubMed - as supplied by publisher]

Opportunities and Challenges for Environmental Exposure Assessment in Population-Based Studies.

Sun, 16/07/2017 - 14:26
Opportunities and Challenges for Environmental Exposure Assessment in Population-Based Studies. Cancer Epidemiol Biomarkers Prev. 2017 Jul 14;: Authors: Patel CJ, Kerr J, Thomas DC, Mukherjee B, Ritz B, Chatterjee N, Jankowska MM, Madan J, Karagas MR, McAllister KA, Mechanic LE, Fallin MD, Ladd-Acosta C, Blair IA, Teiltelbaum SL, Amos CI Abstract BACKGROUND: A growing number and increasing diversity of factors are available for epidemiological studies. These measures provide new avenues for discovery and prevention yet they also raise many challenges for adoption in epidemiological investigations. METHODS: We evaluate 1) designs to investigate diseases that consider heterogeneous and multi-dimensional indicators of exposure and behavior, 2) the implementation of numerous methods to capture indicators of exposure, and 3) the analytical methods required for discovery and validation. RESULTS: Case-control studies have provided insights into genetic susceptibility but are insufficient for characterizing complex effects of environmental factors on disease development. Prospective designs are required but must balance extended data collection with follow-up of study participants. Two phase designs are described. We discuss innovations in assessments including the microbiome, mass spectrometry and metabolomics, behavioral assessment, dietary, physical activity and occupational exposure assessment, air pollution monitoring and global positioning and individual sensors. The availability of extensive correlated data raises new challenges in disentangling specific exposures that influence cancer risk from among extensive and often correlated exposures. CONCLUSIONS: New exposure assessments offer many new opportunities for environmental assessment in cancer development. IMPACT: We describe and evaluate the state of the art for evaluating high dimensional environmental studies. PMID: 28710076 [PubMed - as supplied by publisher]

Circulating Acylcarnitine Profile in Human Heart Failure: A Surrogate of Fatty Acid Metabolic Dysregulation in Mitochondria and Beyond.

Sun, 16/07/2017 - 14:26
Circulating Acylcarnitine Profile in Human Heart Failure: A Surrogate of Fatty Acid Metabolic Dysregulation in Mitochondria and Beyond. Am J Physiol Heart Circ Physiol. 2017 Jul 14;:ajpheart.00820.2016 Authors: Ruiz M, Labarthe F, Fortier A, Bouchard B, Thompson Legault J, Bolduc V, Rigal O, Chen J, Ducharme A, Crawford PA, Tardif JC, Des Rosiers C Abstract Heart failure (HF) is associated with metabolic perturbations, particularly of fatty acids (FA), which remain to be better understood in humans. This study aimed at testing the hypothesis that HF patients with reduced ejection fraction, display systemic perturbations in levels of energy-related metabolites, especially those reflecting dysregulation of FA metabolism, namely acylcarnitines (ACs). Circulating metabolites were assessed using mass spectrometry (MS)-based methods in two cohorts. The main cohort consisted of 72 controls and 68 HF patients, exhibiting depressed left ventricular ejection fraction (25.9±6.9%) and mostly of ischemic etiology with ≥ 2 comorbidities. HF patients displayed marginal changes in plasma levels of Krebs cycle-related metabolites or indices of mitochondrial or cytosolic redox status. They had, however, 22-79% higher circulating ACs, irrespective of chain length (p<0.0001; adjusted for sex, age, renal function and insulin resistance; determined by tandem MS), which reflect defective mitochondrial β-oxidation and were significantly associated with levels of NT-Pro-BNP levels, a disease severity marker. Subsequent extended LC-MS/MS analysis of 53 plasma ACs in a subset group from the primary cohort, confirmed and further substantiated with a comprehensive lipidomic analysis in a validation cohort, revealed in HF patients a more complex circulating AC profile. The latter included dicarboxylic-ACs and dihydroxy-ACs as well as AC or sphingolipids with very-long chain (VLC)-FAs (>20 carbons), which are proxies of dysregulated FA metabolism in peroxisomes. Our study identified alterations in circulating ACs in HF patients, which are independent of biological traits and associated with disease severity markers. These alterations reflect dysfunctional FA metabolism in mitochondria, but also beyond, namely in peroxisomes, suggesting a novel mechanism contributing to global lipid perturbations in human HF. PMID: 28710072 [PubMed - as supplied by publisher]

Create, run, share, publish, and reference your LC-MS, FIA-MS, GC-MS, and NMR data analysis workflows with Workflow4Metabolomics 3.0, the Galaxy online infrastructure for metabolomics.

Sun, 16/07/2017 - 14:26
Create, run, share, publish, and reference your LC-MS, FIA-MS, GC-MS, and NMR data analysis workflows with Workflow4Metabolomics 3.0, the Galaxy online infrastructure for metabolomics. Int J Biochem Cell Biol. 2017 Jul 11;: Authors: Guitton Y, Tremblay-Franco M, Le Corguillé G, Martin JF, Pétéra M, Roger-Mele P, Delabrière A, Goulitquer S, Monsoor M, Duperier C, Canlet C, Servien R, Tardivel P, Caron C, Giacomoni F, Thévenot EA Abstract Metabolomics is a key approach in modern functional genomics and systems biology. Due to the complexity of metabolomics data, the variety of experimental designs, and the variety of existing bioinformatics tools, providing experimenters with a simple and efficient resource to conduct comprehensive and rigorous analysis of their data is of utmost importance. In 2014, we launched the Workflow4Metabolomics (W4M; http://workflow4metabolomics.org) online infrastructure for metabolomics built on the Galaxy environment, which offers user-friendly features to build and run data analysis workflows including preprocessing, statistical analysis, and annotation steps. Here we present the new W4M 3.0 release, which contains twice as many tools as the first version, and provides two features which are, to our knowledge, unique among online resources. First, data from the four major metabolomics technologies (i.e., LC-MS, FIA-MS, GC-MS, and NMR) can be analyzed on a single platform. By using three studies in human physiology, alga evolution, and animal toxicology, we demonstrate how the 40 available tools can be easily combined to address biological issues. Second, the full analysis (including the workflow, the parameter values, the input data and output results) can be referenced with a permanent digital object identifier (DOI). Publication of data analyses is of major importance for robust and reproducible science. Furthermore, the publicly shared workflows are of high-value for e-learning and training. The Workflow4Metabolomics 3.0 e-infrastructure thus not only offers a unique online environment for analysis of data from the main metabolomics technologies, but it is also the first reference repository for metabolomics workflows. PMID: 28710041 [PubMed - as supplied by publisher]

The analytical process to search for metabolomics biomarkers.

Sun, 16/07/2017 - 14:26
The analytical process to search for metabolomics biomarkers. J Pharm Biomed Anal. 2017 Jul 06;: Authors: Luque de Castro MD, Priego-Capote F Abstract The scant number of available metabolomics biomarkers does not reflect the extent of the research in this field. Looking for the reasons of failure, the authors, as analytical chemists, critically discuss each of the steps in the analytical process that requires improvements. They find insufficient information about how the experimental part is developed. After revising the steps from sampling to obtainment of the analytical sample (from typical samples such as blood and urine to others less common such as sweat or saliva), the need for data and metadata for either reproduction of a given study or for taking the study as starting point after biomarker discovery is criticized. The separation and analysis steps are also revised as does data treatment. After the sources of errors from the analytical process are overcome, subsequent steps in the implementation of biomarkers to reach the final aim of clinical adoption should be supported as required. PMID: 28709716 [PubMed - as supplied by publisher]

Peripheral biomarkers of major depression and antidepressant treatment response: Current knowledge and future outlooks.

Sun, 16/07/2017 - 14:26
Peripheral biomarkers of major depression and antidepressant treatment response: Current knowledge and future outlooks. J Affect Disord. 2017 Jul 05;: Authors: Gadad BS, Jha MK, Czysz A, Furman JL, Mayes TL, Emslie MP, Trivedi MH Abstract BACKGROUND: In recent years, we have accomplished a deeper understanding about the pathophysiology of major depressive disorder (MDD). Nevertheless, this improved comprehension has not translated to improved treatment outcome, as identification of specific biologic markers of disease may still be crucial to facilitate a more rapid, successful treatment. Ongoing research explores the importance of screening biomarkers using neuroimaging, neurophysiology, genomics, proteomics, and metabolomics measures. RESULTS: In the present review, we highlight the biomarkers that are differentially expressed in MDD and treatment response and place a particular emphasis on the most recent progress in advancing technology which will continue the search for blood-based biomarkers. LIMITATIONS: Due to space constraints, we are unable to detail all biomarker platforms, such as neurophysiological and neuroimaging markers, although their contributions are certainly applicable to a biomarker review and valuable to the field. CONCLUSIONS: Although the search for reliable biomarkers of depression and/or treatment outcome is ongoing, the rapidly-expanding field of research along with promising new technologies may provide the foundation for identifying key factors which will ultimately help direct patients toward a quicker and more effective treatment for MDD. PMID: 28709695 [PubMed - as supplied by publisher]

A novel Alzheimer's disease drug candidate targeting inflammation and fatty acid metabolism.

Sun, 16/07/2017 - 14:26
A novel Alzheimer's disease drug candidate targeting inflammation and fatty acid metabolism. Alzheimers Res Ther. 2017 Jul 14;9(1):50 Authors: Daugherty D, Goldberg J, Fischer W, Dargusch R, Maher P, Schubert D Abstract BACKGROUND: CAD-31 is an Alzheimer's disease (AD) drug candidate that was selected on the basis of its ability to stimulate the replication of human embryonic stem cell-derived neural precursor cells as well as in APPswe/PS1ΔE9 AD mice. To move CAD-31 toward the clinic, experiments were undertaken to determine its neuroprotective and pharmacological properties, as well as to assay its therapeutic efficacy in a rigorous mouse model of AD. RESULTS: CAD-31 has potent neuroprotective properties in six distinct nerve cell assays that mimic toxicities observed in the old brain. Pharmacological and preliminary toxicological studies show that CAD-31 is brain-penetrant and likely safe. When fed to old, symptomatic APPswe/PS1ΔE9 AD mice starting at 10 months of age for 3 additional months in a therapeutic model of the disease, there was a reduction in the memory deficit and brain inflammation, as well as an increase in the expression of synaptic proteins. Small-molecule metabolic data from the brain and plasma showed that the major effect of CAD-31 is centered on fatty acid metabolism and inflammation. Pathway analysis of gene expression data showed that CAD-31 had major effects on synapse formation and AD energy metabolic pathways. CONCLUSIONS: All of the multiple physiological effects of CAD-31 were favorable in the context of preventing some of the toxic events in old age-associated neurodegenerative diseases. PMID: 28709449 [PubMed - in process]

Integrating multi-omics analyses of Nonomuraea dietziae to reveal the role of soybean oil in [(4'-OH)MeLeu](4)-CsA overproduction.

Sun, 16/07/2017 - 14:26
Integrating multi-omics analyses of Nonomuraea dietziae to reveal the role of soybean oil in [(4'-OH)MeLeu](4)-CsA overproduction. Microb Cell Fact. 2017 Jul 14;16(1):120 Authors: Liu H, Huang D, Jin L, Wang C, Liang S, Wen J Abstract BACKGROUND: Nonomuraea dietziae is a promising microorganism to mediate the region-specific monooxygenation reaction of cyclosporine A (CsA). The main product [(4'-OH)MeLeu](4)-CsA possesses high anti-HIV/HCV and hair growth-stimulating activities while avoiding the immunosuppressive effect of CsA. However, the low conversion efficiency restricts the clinical application. In this study, the production of [(4'-OH)MeLeu](4)-CsA was greatly improved by 55.6% from 182.8 to 284.4 mg/L when supplementing soybean oil into the production medium, which represented the highest production of [(4'-OH)MeLeu](4)-CsA so far. RESULTS: To investigate the effect of soybean oil on CsA conversion, some other plant oils (corn oil and peanut oil) and the major hydrolysates of soybean oil were fed into the production medium, respectively. The results demonstrated that the plant oils, rather than the hydrolysates, could significantly improve the [(4'-OH)MeLeu](4)-CsA production, suggesting that soybean oil might not play its role in the lipid metabolic pathway. To further unveil the mechanism of [(4'-OH)MeLeu](4)-CsA overproduction under the soybean oil condition, a proteomic analysis based on the two-dimensional gel electrophoresis coupled with MALDI TOF/TOF mass spectrometry was implemented. The results showed that central carbon metabolism, genetic information processing and energy metabolism were significantly up-regulated under the soybean oil condition. Moreover, the gas chromatography-mass spectrometry-based metabolomic analysis indicated that soybean oil had a great effect on amino acid metabolism and tricarboxylic acid cycle. In addition, the transcription levels of cytochrome P450 hydroxylase (CYP) genes for CsA conversion were determined by RT-qPCR and the results showed that most of the CYP genes were up-regulated under the soybean oil condition. CONCLUSIONS: These findings indicate that soybean oil could strengthen the primary metabolism and the CYP system to enhance the mycelium growth and the monooxygenation reaction, respectively, and it will be a guidance for the further metabolic engineering of this strain. PMID: 28709434 [PubMed - in process]

Rho kinase proteins display aberrant upregulation in vascular tumors and contribute to vascular tumor growth.

Sun, 16/07/2017 - 14:26
Rho kinase proteins display aberrant upregulation in vascular tumors and contribute to vascular tumor growth. BMC Cancer. 2017 Jul 14;17(1):485 Authors: Amaya CN, Mitchell DC, Bryan BA Abstract BACKGROUND: The serine/threonine protein kinases ROCK1 and 2 are key RhoA-mediated regulators of cell shape and cytoskeletal dynamics. These proteins perform multiple functions in vascular endothelial cell physiology and are attractive targets for cancer therapy based on their roles as oncogenes and metastatic promoters. Given their critical functions in both of these processes, we hypothesized that molecular targeting of ROCK proteins would be exceedingly effective against vascular tumors such as hemangiomas and angiosarcomas, which are neoplasms composed of aberrant endothelial cells. METHODS: In this study, we compared ROCK1 and 2 protein expression in a large panel of benign and malignant vascular tumors to that of normal vasculature. We then utilized shRNA technology to knockdown the expression of ROCK1 and 2 in SVR tumor-forming vascular cells, and evaluated tumor size and proliferation rate in a xenograft model. Finally, we employed proteomics and metabolomics to assess how knockdown of the ROCK paralogs induced alterations in protein expression/phosphorylation and metabolite concentrations in the xenograft tumors. RESULTS: Our findings revealed that ROCK1 was overexpressed in malignant vascular tumors such as hemangioendotheliomas and angiosarcomas, and ROCK2 was overexpressed in both benign and malignant vascular tumors including hemangiomas, hemangioendotheliomas, hemangiopericytomas, and angiosarcomas. shRNA-mediated knockdown of ROCK2, but not ROCK1, in xenograft vascular tumors significantly reduced tumor size and proliferative index compared to control tumors. Proteomics and metabolomics analysis of the xenograft tumors revealed both overlapping as well as unique roles for the ROCK paralogs in regulating signal transduction and metabolite concentrations. CONCLUSIONS: Collectively, these data indicate that ROCK proteins are overexpressed in diverse vascular tumors and suggest that specific targeting of ROCK2 proteins may show efficacy against malignant vascular tumors. PMID: 28709411 [PubMed - in process]

Structure elucidation of metabolite x17299 by interpretation of mass spectrometric data.

Sat, 15/07/2017 - 13:41
Structure elucidation of metabolite x17299 by interpretation of mass spectrometric data. Metabolomics. 2017;13(8):92 Authors: Zhang Q, Ford LA, Evans AM, Toal DR Abstract INTRODUCTION: A major bottleneck in metabolomic studies is metabolite identification from accurate mass spectrometric data. Metabolite x17299 was identified in plasma as an unknown in a metabolomic study using a compound-centric approach where the associated ion features of the compound were used to determine the true molecular mass. OBJECTIVES: The aim of this work is to elucidate the chemical structure of x17299, a new compound by de novo interpretation of mass spectrometric data. METHODS: An Orbitrap Elite mass spectrometer was used for acquisition of mass spectra up to MS(4) at high resolution. Synthetic standards of N,N,N-trimethyl-l-alanyl-l-proline betaine (l,l-TMAP), a diastereomer, and an enantiomer were chemically prepared. RESULTS: The planar structure of x17299 was successfully proposed by de novo mechanistic interpretation of mass spectrometric data without any laborious purification and nuclear magnetic resonance spectroscopic analysis. The proposed structure was verified by deuterium exchanged mass spectrometric analysis and confirmed by comparison to a synthetic standard. Relative configuration of x17299 was determined by direct chromatographic comparison to a pair of synthetic diastereomers. Absolute configuration was assigned after derivatization of x17299 with a chiral auxiliary group followed by its chromatographic comparison to a pair of synthetic standards. CONCLUSION: The chemical structure of metabolite x17299 was determined to be l,l-TMAP. PMID: 28706470 [PubMed]

Metabolic response of porcine colon explants to in vitro infection by Brachyspira hyodysenteriae: a leap into disease pathophysiology.

Sat, 15/07/2017 - 13:41
Metabolic response of porcine colon explants to in vitro infection by Brachyspira hyodysenteriae: a leap into disease pathophysiology. Metabolomics. 2017;13(7):83 Authors: Welle T, Hoekstra AT, Daemen IAJJM, Berkers CR, Costa MO Abstract INTRODUCTION: Swine dysentery caused by Brachyspira hyodysenteriae is a production limiting disease in pig farming. Currently antimicrobial therapy is the only treatment and control method available. OBJECTIVE: The aim of this study was to characterize the metabolic response of porcine colon explants to infection by B. hyodysenteriae. METHODS: Porcine colon explants exposed to B. hyodysenteriae were analyzed for histopathological, metabolic and pro-inflammatory gene expression changes. RESULTS: Significant epithelial necrosis, increased levels of l-citrulline and IL-1α were observed on explants infected with B. hyodysenteriae. CONCLUSIONS: The spirochete induces necrosis in vitro likely through an inflammatory process mediated by IL-1α and NO. PMID: 28706469 [PubMed]

Retinal metabolic events in preconditioning light stress as revealed by wide-spectrum targeted metabolomics.

Sat, 15/07/2017 - 13:41
Retinal metabolic events in preconditioning light stress as revealed by wide-spectrum targeted metabolomics. Metabolomics. 2017;13(3):22 Authors: de la Barca JMC, Huang NT, Jiao H, Tessier L, Gadras C, Simard G, Natoli R, Tcherkez G, Reynier P, Valter K Abstract INTRODUCTION: Light is the primary stimulus for vision, but may also cause damage to the retina. Pre-exposing the retina to sub-lethal amount of light (or preconditioning) improves chances for retinal cells to survive acute damaging light stress. OBJECTIVES: This study aims at exploring the changes in retinal metabolome after mild light stress and identifying mechanisms that may be involved in preconditioning. METHODS: Retinas from 12 rats exposed to mild light stress (1000 lux × for 12 h) and 12 controls were collected one and seven days after light stress (LS). One retina was used for targeted metabolomics analysis using the Biocrates p180 kit while the fellow retina was used for histological and immunohistochemistry analysis. RESULTS: Immunohistochemistry confirmed that in this experiment, a mild LS with retinal immune response and minimal photoreceptor loss occurred. Compared to controls, LS induced an increased concentration in phosphatidylcholines. The concentration in some amino acids and biogenic amines, particularly those related to the nitric oxide pathway (like asymmetric dimethylarginine (ADMA), arginine and citrulline) also increased 1 day after LS. 7 days after LS, the concentration in two sphingomyelins and phenylethylamine was found to be higher. We further found that in controls, retina metabolome was different between males and females: male retinas had an increased concentration in tyrosine, acetyl-ornithine, phosphatidylcholines and (acyl)-carnitines. CONCLUSIONS: Besides retinal sexual metabolic dimorphism, this study shows that preconditioning is mostly associated with re-organisation of lipid metabolism and changes in amino acid composition, likely reflecting the involvement of arginine-dependent NO signalling. PMID: 28706468 [PubMed]

Affinity purification of erythropoietin from cell culture supernatant combined with MALDI-TOF-MS analysis of erythropoietin N-glycosylation.

Sat, 15/07/2017 - 13:41
Affinity purification of erythropoietin from cell culture supernatant combined with MALDI-TOF-MS analysis of erythropoietin N-glycosylation. Sci Rep. 2017 Jul 13;7(1):5324 Authors: Falck D, Haberger M, Plomp R, Hook M, Bulau P, Wuhrer M, Reusch D Abstract Erythropoietin (EPO) is a heavily glycosylated hormone whose recombinant forms are used for treatment of anaemia. EPO glycosylation is important for its pharmacological properties. An analytical workflow, which can determine EPO glycosylation in an accurate and high-throughput fashion from cell culture supernatant (CCS) in approximately 24 h, offers the possibility to follow changes during production. To address this challenge, we present a complete workflow consisting of protein purification, glycan release, sialic acid derivatization, solid phase extraction, matrix-assisted laser desorption/ionization - mass spectrometry (MALDI-MS) analysis and MassyTools data processing. EPO purification from CCS by anti-EPO antibody coupled Sepharose beads yielded excellent purity with acceptable recovery and was free of glycoform bias. Glycosylation profiles obtained by MALDI-MS were highly comparable to those obtained with an established capillary gel electrophoresis-laser induced fluorescence method. Our method delivers accurate results for the analysis of changes of important glycosylation parameters, such as sialylation and number of N-acetyllactosamine units, for the time course of a fermentation. We could resolve differences in glycosylation between several CCS samples. PMID: 28706253 [PubMed - in process]

Inhibitor of growth protein 4 interacts with Beclin 1 and represses autophagy.

Sat, 15/07/2017 - 13:41
Inhibitor of growth protein 4 interacts with Beclin 1 and represses autophagy. Oncotarget. 2017 Jul 06;: Authors: Sica V, Bravo-San Pedro JM, Chen G, Mariño G, Lachkar S, Izzo V, Maiuri MC, Niso-Santano M, Kroemer G Abstract Beclin 1 (BECN1) is a multifunctional protein that activates the pro-autophagic class III phosphatidylinositol 3-kinase (PIK3C3, best known as VPS34), yet also interacts with multiple negative regulators. Here we report that BECN1 interacts with inhibitor of growth family member 4 (ING4), a tumor suppressor protein that is best known for its capacity to interact with the tumor suppressor protein p53 (TP53) and the acetyltransferase E1A binding protein p300 (EP300). Removal of TP53 or EP300 did not affect the BECN1/ING4 interaction, which however was lost upon culture of cells in autophagy-inducing, nutrient free conditions. Depletion of ING4 stimulated the enzymatic activity of PIK3C3, as visualized by means of a red fluorescent protein-tagged short peptide (FYVE) that specifically binds to phosphatidylinositol-3-phosphate (PI3P)-containing subcellular vesicles and enhanced autophagy, as indicated by an enhanced lipidation of microtubule-associated proteins 1A/1B light chain 3 beta (LC3B) and the redistribution of a green-fluorescent protein (GFP)-LC3B fusion protein to cytoplasmic puncta. The generation of GFP-LC3B puncta stimulated by ING4 depletion was reduced by simultaneous depletion, or pharmacological inhibition, of PIK3C3/VPS34. In conclusion, ING4 acts as a negative regulator of the lipid kinase activity of the BECN1 complex, and starvation-induced autophagy is accompanied by the dissociation of the ING4/BECN1 interaction. PMID: 28706153 [PubMed - as supplied by publisher]

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