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

Salinity tolerance is related to cyanide-resistant alternative respiration in Medicago truncatula under sudden severe stress.

Thu, 16/06/2016 - 14:40
Related Articles Salinity tolerance is related to cyanide-resistant alternative respiration in Medicago truncatula under sudden severe stress. Plant Cell Environ. 2016 Jun 15; Authors: Fernández Del-Saz N, Florez-Sarasa I, Clemente-Moreno MJ, Mhadhbi H, Flexas J, Fernie AR, Ribas-Carbó M Abstract Salt respiration is defined as the increase of respiration under early salt stress. However, the response of respiration varies depending on the degree of salt tolerance and salt stress. It has been hypothesized that the activity of the alternative pathway may increase preventing over-reduction of the ubiquinone pool in response to salinity, which in turn can increase respiration. Three genotypes of Medicago truncatula are reputed as differently responsive to salinity: TN1.11, A17 and TN6.18. We used the oxygen-isotope fractionation technique to study the in vivo respiratory activities of the cytochrome oxidase pathway (COP) and the alternative oxidase pathway (AOP) in leaves and roots of these genotypes treated with severe salt stress (300 mM) during 1 and 3 days. In parallel, AOX capacity, gas exchange measurements, relative water content and metabolomics were determined in control and treated plants. Our study shows for first time that salt respiration is induced by the triggered AOP in response to salinity. Moreover, this phenomenon coincides with increased levels of metabolites such as amino and organic acids, and is shown to be related with higher photosynthetic rate and water content in TN6.18. PMID: 27304415 [PubMed - as supplied by publisher]

Microbiome-Metabolome Responses in the Cecum and Colon of Pig to a High Resistant Starch Diet.

Thu, 16/06/2016 - 14:40
Related Articles Microbiome-Metabolome Responses in the Cecum and Colon of Pig to a High Resistant Starch Diet. Front Microbiol. 2016;7:779 Authors: Sun Y, Su Y, Zhu W Abstract Currently, knowledge about the impact of long-term intake of high resistant starch diet on pig hindgut microbiota and metabolite profile is limited. In this study, a combination of the pyrosequencing and the mass spectrometry (MS)-based metabolomics techniques were used to investigate the effects of a raw potato starch (RPS, high in resistant starch) diet on microbial composition and microbial metabolites in the hindgut of pig. The results showed that Coprococcus, Ruminococcus, and Turicibacter increased significantly, while Sarcina and Clostridium decreased in relative abundances in the hindgut of pigs fed RPS. The metabolimic analysis revealed that RPS significantly affected starch and sucrose metabolites, amino acid turnover or protein biosynthesis, lipid metabolites, glycolysis, the pentose phosphate pathway, inositol phosphate metabolism, and nucleotide metabolism. Furthermore, a Pearson's correlation analysis showed that Ruminococcus and Coprococcus were positively correlated with glucose-6-phosphate, maltose, arachidonic acid, 9, 12-octadecadienoic acid, oleic acid, phosphate, but negatively correlated with α-aminobutyric acid. However, the correlation of Clostridium and Sarcina with these compounds was in the opposite direction. The results suggest that RPS not only alters the composition of the gut microbial community but also modulates the metabolic pathway of microbial metabolism, which may further affect the hindgut health of the host. PMID: 27303373 [PubMed]

Metabolomics of aging requires large-scale longitudinal studies with replication.

Thu, 16/06/2016 - 14:40
Related Articles Metabolomics of aging requires large-scale longitudinal studies with replication. Proc Natl Acad Sci U S A. 2016 Jun 14; Authors: Mäkinen VP, Ala-Korpela M PMID: 27303027 [PubMed - as supplied by publisher]

Reply to Mäkinen and Ala-Korpela: Small-scale but accurate metabolomics with high reproducibility for identifying age-related blood metabolites.

Thu, 16/06/2016 - 14:40
Related Articles Reply to Mäkinen and Ala-Korpela: Small-scale but accurate metabolomics with high reproducibility for identifying age-related blood metabolites. Proc Natl Acad Sci U S A. 2016 Jun 14; Authors: Kondoh H, Yanagida M PMID: 27303026 [PubMed - as supplied by publisher]

Longitudinal monitoring of immunoglobulin A glycosylation during pregnancy by simultaneous MALDI-FTICR-MS analysis of N- and O-glycopeptides.

Thu, 16/06/2016 - 14:40
Related Articles Longitudinal monitoring of immunoglobulin A glycosylation during pregnancy by simultaneous MALDI-FTICR-MS analysis of N- and O-glycopeptides. Sci Rep. 2016;6:27955 Authors: Bondt A, Nicolardi S, Jansen BC, Stavenhagen K, Blank D, Kammeijer GS, Kozak RP, Fernandes DL, Hensbergen PJ, Hazes JM, van der Burgt YE, Dolhain RJ, Wuhrer M Abstract Immunoglobulin A (IgA) is a glycoprotein of which altered glycosylation has been associated with several pathologies. Conventional methods for IgA N- and O-glycosylation analysis are tedious, thus limiting such analyses to small sample sizes. Here we present a high-throughput strategy for the simultaneous analysis of serum-derived IgA1 N- and O-glycopeptides using matrix-assisted laser/desorption ionisation Fourier transform ion cyclotron resonance (MALDI-FTICR) mass spectrometry (MS). Six non-fucosylated diantennary complex type glycoforms were detected on the Asn144-containing glycopeptide. Thirteen distinct glycoforms were identified for the Asn340-containing tailpiece glycopeptide, mainly of the diantennary complex type, and low amounts of triantennary glycoforms. Simultaneously with these N-glycopeptides, 53 compositional glycoforms of the hinge region O-glycopeptide were profiled in a single high resolution MALDI-FTICR spectrum. Since many pregnancy associated changes have been recognized for immunoglobulin G, we sought to demonstrate the clinical applicability of this method in a cohort of 29 pregnant women, from whom samples were collected at three time points during pregnancy and three time points after delivery. Pregnancy associated changes of N-glycan bisection were different for IgA1 as compared to IgG-Fc described earlier. We foresee further applications of the developed method for larger patient cohorts to study IgA N- and O-glycosylation changes in pathologies. PMID: 27302155 [PubMed - in process]

LC-MS based metabolomics and chemometrics study of the toxic effects of copper on Saccharomyces cerevisiae.

Thu, 16/06/2016 - 14:40
Related Articles LC-MS based metabolomics and chemometrics study of the toxic effects of copper on Saccharomyces cerevisiae. Metallomics. 2016 Jun 15; Authors: Farrés M, Piña B, Tauler R Abstract Copper containing fungicides are used to protect vineyards from fungal infections. Higher residues of copper in grapes at toxic concentrations are potentially toxic and affect the microorganisms living in vineyards, such as Saccharomyces cerevisiae. In this study, the response of the metabolic profiles of S. cerevisiae at different concentrations of copper sulphate (control, 1 mM, 3 mM and 6 mM) was analysed by liquid chromatography coupled to mass spectrometry (LC-MS) and multivariate curve resolution-alternating least squares (MCR-ALS) using an untargeted metabolomics approach. Peak areas of the MCR-ALS resolved elution profiles in control and in Cu(ii)-treated samples were compared using partial least squares regression (PLSR) and PLS-discriminant analysis (PLS-DA), and the intracellular metabolites best contributing to sample discrimination were selected and identified. Fourteen metabolites showed significant concentration changes upon Cu(ii) exposure, following a dose-response effect. The observed changes were consistent with the expected effects of Cu(ii) toxicity, including oxidative stress and DNA damage. This research confirmed that LC-MS based metabolomics coupled to chemometric methods are a powerful approach for discerning metabolomics changes in S. cerevisiae and for elucidating modes of toxicity of environmental stressors, including heavy metals like Cu(ii). PMID: 27302082 [PubMed - as supplied by publisher]

Fructose promotes growth and antifungal activity of Penicillium citrinum.

Thu, 16/06/2016 - 14:40
Related Articles Fructose promotes growth and antifungal activity of Penicillium citrinum. Protein Cell. 2016 Jun 15; Authors: Wu CW, Wu X, Wen C, Peng B, Peng XX, Chen X, Li H PMID: 27301255 [PubMed - as supplied by publisher]

Proteomic and Metabolomic Analyses Reveal Contrasting Anti-Inflammatory Effects of an Extract of Mucor Racemosus Secondary Metabolites Compared to Dexamethasone.

Thu, 16/06/2016 - 14:40
Related Articles Proteomic and Metabolomic Analyses Reveal Contrasting Anti-Inflammatory Effects of an Extract of Mucor Racemosus Secondary Metabolites Compared to Dexamethasone. PLoS One. 2015;10(10):e0140367 Authors: Meier SM, Muqaku B, Ullmann R, Bileck A, Kreutz D, Mader JC, Knasmüller S, Gerner C Abstract Classical drug assays are often confined to single molecules and targeting single pathways. However, it is also desirable to investigate the effects of complex mixtures on complex systems such as living cells including the natural multitude of signalling pathways. Evidence based on herbal medicine has motivated us to investigate potential beneficial health effects of Mucor racemosus (M rac) extracts. Secondary metabolites of M rac were collected using a good-manufacturing process (GMP) approved production line and a validated manufacturing process, in order to obtain a stable product termed SyCircue (National Drug Code USA: 10424-102). Toxicological studies confirmed that this product does not contain mycotoxins and is non-genotoxic. Potential effects on inflammatory processes were investigated by treating stimulated cells with M rac extracts and the effects were compared to the standard anti-inflammatory drug dexamethasone on the levels of the proteome and metabolome. Using 2D-PAGE, slight anti-inflammatory effects were observed in primary white blood mononuclear cells, which were more pronounced in primary human umbilical vein endothelial cells (HUVECs). Proteome profiling based on nLC-MS/MS analysis of tryptic digests revealed inhibitory effects of M rac extracts on pro-inflammatory cytoplasmic mediators and secreted cytokines and chemokines in these endothelial cells. This finding was confirmed using targeted proteomics, here treatment of stimulated cells with M rac extracts down-regulated the secretion of IL-6, IL-8, CXCL5 and GROA significantly. Finally, the modulating effects of M rac on HUVECs were also confirmed on the level of the metabolome. Several metabolites displayed significant concentration changes upon treatment of inflammatory activated HUVECs with the M rac extract, including spermine and lysophosphatidylcholine acyl C18:0 and sphingomyelin C26:1, while the bulk of measured metabolites remained unaffected. Interestingly, the effects of M rac treatment on lipids were orthogonal to the effect of dexamethasone underlining differences in the overall mode of action. PMID: 26496078 [PubMed - indexed for MEDLINE]

Maternal Early Pregnancy Serum Metabolomics Profile and Abnormal Vaginal Bleeding as Predictors of Placental Abruption: A Prospective Study.

Wed, 15/06/2016 - 14:02
Related Articles Maternal Early Pregnancy Serum Metabolomics Profile and Abnormal Vaginal Bleeding as Predictors of Placental Abruption: A Prospective Study. PLoS One. 2016;11(6):e0156755 Authors: Gelaye B, Sumner SJ, McRitchie S, Carlson JE, Ananth CV, Enquobahrie DA, Qiu C, Sorensen TK, Williams MA Abstract BACKGROUND & OBJECTIVE: Placental abruption, an ischemic placental disorder, complicates about 1 in 100 pregnancies, and is an important cause of maternal and perinatal morbidity and mortality worldwide. Metabolomics holds promise for improving the phenotyping, prediction and understanding of pathophysiologic mechanisms of complex clinical disorders including abruption. We sought to evaluate maternal early pregnancy pre-diagnostic serum metabolic profiles and abnormal vaginal bleeding as predictors of abruption later in pregnancy. METHODS: Maternal serum was collected in early pregnancy (mean 16 weeks, range 15 to 22 weeks) from 51 abruption cases and 51 controls. Quantitative targeted metabolic profiles of serum were acquired using electrospray ionization liquid chromatography-mass spectrometry (ESI-LC-MS/MS) and the Absolute IDQ® p180 kit. Maternal sociodemographic characteristics and reproductive history were abstracted from medical records. Stepwise logistic regression models were developed to evaluate the extent to which metabolites aid in the prediction of abruption. We evaluated the predictive performance of the set of selected metabolites using a receiver operating characteristics (ROC) curve analysis and area under the curve (AUC). RESULTS: Early pregnancy vaginal bleeding, dodecanoylcarnitine/dodecenoylcarnitine (C12 / C12:1), and phosphatidylcholine acyl-alkyl C 38:1 (PC ae C38:1) strongly predict abruption risk. The AUC for these metabolites alone was 0.68, for early pregnancy vaginal bleeding alone was 0.65, and combined the AUC improved to 0.75 with the addition of quantitative metabolite data (P = 0.003). CONCLUSION: Metabolomic profiles of early pregnancy maternal serum samples in addition to the clinical symptom, vaginal bleeding, may serve as important markers for the prediction of abruption. Larger studies are necessary to corroborate and validate these findings in other cohorts. PMID: 27300725 [PubMed - as supplied by publisher]

A Multiplatform Metabolomics Approach to Characterize Plasma Levels of Phenylalanine and Tyrosine in Phenylketonuria.

Wed, 15/06/2016 - 14:02
Related Articles A Multiplatform Metabolomics Approach to Characterize Plasma Levels of Phenylalanine and Tyrosine in Phenylketonuria. JIMD Rep. 2016 Jun 15; Authors: Blasco H, Veyrat-Durebex C, Bertrand M, Patin F, Labarthe F, Henique H, Emond P, Andres CR, Antar C, Landon C, Nadal-Desbarats L, Maillot F Abstract BACKGROUND: Different pathophysiological mechanisms have been described in phenylketonuria (PKU) but the indirect metabolic consequences of metabolic disorders caused by elevated Phe or low Tyr concentrations remain partially unknown. We used a multiplatform metabolomics approach to evaluate the metabolic signature associated with Phe and Tyr. MATERIAL AND METHODS: We prospectively included 10 PKU adult patients and matched controls. We analysed the metabolome profile using GC-MS (urine), amino-acid analyzer (urine and plasma) and nuclear magnetic resonance spectroscopy (urine). We performed a multivariate analysis from the metabolome (after exclusion of Phe, Tyr and directly derived metabolites) to explain plasma Phe and Tyr concentrations, and the clinical status. Finally, we performed a univariate analysis of the most discriminant metabolites and we identified the associated metabolic pathways. RESULTS: We obtained a metabolic pattern from 118 metabolites and we built excellent multivariate models to explain Phe, Tyr concentrations and PKU diagnosis. Common metabolites of these models were identified: Gln, Arg, succinate and alpha aminobutyric acid. Univariate analysis showed an inverse correlation between Arg, alpha aminobutyric acid and Phe and a positive correlation between Arg, succinate, Gln and Tyr (p < 0.0003). Thus, we highlighted the following pathways: Arg and Pro, Ala, Asp and Glu metabolism. DISCUSSION: We obtain a specific metabolic signature related to Tyr and Phe concentrations. We confirmed the involvement of different pathophysiological mechanisms previously described in PKU such as protein synthesis, energetic metabolism and oxidative stress. The metabolomics approach is relevant to explore PKU pathogenesis. PMID: 27300702 [PubMed - as supplied by publisher]

Metabolic dynamics of Desulfovibrio vulgaris biofilm grown on a steel surface.

Wed, 15/06/2016 - 14:02
Related Articles Metabolic dynamics of Desulfovibrio vulgaris biofilm grown on a steel surface. Biofouling. 2016 Aug;32(7):725-736 Authors: Zhang Y, Pei G, Chen L, Zhang W Abstract In this study, a comparative metabolomics approach combining gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) was applied first between planktonic cells and biofilms and then between pure cultures and biofilms of Desulfovibrio vulgaris. The results revealed that the overall metabolic level of the biofilm cells was down-regulated, especially for metabolites related to the central carbon metabolism, compared to the planktonic cells and the pure culture of D. vulgaris. In addition, pathway enrichment analysis of the 58 metabolites identified by GC-MS showed that fatty acid biosynthesis in the biofilm cells was up-regulated, suggesting that fatty acids may be important for the formation, maintenance and function of D. vulgaris biofilm. This study offers a valuable perspective on the metabolic dynamics of the D. vulgaris biofilm. PMID: 27299565 [PubMed - as supplied by publisher]

Modulating the direction of carbon flow in Escherichia coli to improve L-tryptophan production by inactivating the global regulator FruR.

Wed, 15/06/2016 - 14:02
Related Articles Modulating the direction of carbon flow in Escherichia coli to improve L-tryptophan production by inactivating the global regulator FruR. J Biotechnol. 2016 Jun 10; Authors: Liu L, Duanabd X, Wu J Abstract The fructose repressor (FruR) affects carbon flux through the central metabolic pathways of E. coli. In this study, L-tryptophan production in Escherichia coli FB-04 was improved by knocking out the fruR gene, thereby inactivating FruR. This fruR knockout strain, E. coli FB-04(ΔfruR), not only exhibited higher growth efficiency, it also showed substantially improved L-tryptophan production. L-tryptophan production by E. coli FB-04(ΔfruR) and L-tryptophan yield per glucose were increased by 62.5% and 52.4%, respectively, compared with the parent E. coli FB-04. Metabolomics analysis showed that the fruR knockout significantly enhances metabolic flow through glycolysis, the pentose phosphate pathway and the TCA cycle, increasing levels of critical precursors and substrates for L-tryptophan biosynthesis. These results indicate that fruR deletion should enhance L-tryptophan production and improve the efficiency of carbon source utilization independent of genetic background. PMID: 27297546 [PubMed - as supplied by publisher]

A Subset of Protective γ9δ2 T cells is Activated by Novel Mycobacterial Lipid Components.

Wed, 15/06/2016 - 14:02
Related Articles A Subset of Protective γ9δ2 T cells is Activated by Novel Mycobacterial Lipid Components. Infect Immun. 2016 Jun 13; Authors: Xia M, Hesser DC, De P, Sakala IG, Spencer CT, Kirkwood JS, Abate G, Chatterjee D, Dobos KM, Hoft DF Abstract γ9δ2 T cells provide a natural bridge between innate and adaptive immunity, rapidly and potently respond to pathogen infection in mucosal tissues, and are prominently induced by both tuberculosis (TB) infection and bacillus Calmette Guérin (BCG) vaccination. Mycobacteria-expanded γ9δ2 T cells represent only a subset of the phosphoantigen (IPP and HMBPP)-responsive γ9δ2 T cells, expressing an oligoclonal set of TCR sequences which more efficiently recognize and inhibit intracellular Mycobacterium tuberculosis (Mtb) infection. Based on this premise, we have been searching for Mtb antigens specifically capable of inducing a unique subset of mycobacteria-protective γ9δ2 T cells. Our screening strategy includes the identification of Mtb fractions that expand γ9δ2 T cells with biological functions capable of inhibiting intracellular mycobacteria replication. Chemical treatments of Mtb whole lysates (WL) ruled out protein, nucleic acid and nonpolar lipids as the Mtb antigens inducing protective γ9δ2 T cells. Mild acid hydrolysis, which transforms complex carbohydrate to monomeric residues, abrogated the specific activity of Mtb whole cell lysate, suggesting that a polysaccharide was required for biological activity. Extraction of MtbWL with chloroform: methanol: water (10:10:3) resulted in a polar lipid fraction with highly enriched specific activity; this activity was further enriched by silica gel chromatography. A combination of Mass Spectrometry and Nuclear Magnetic Resonance analysis of bioactive fractions indicated that 6-O-methyl-glucose containing lipopolysaccharides (mGLP) are predominant components present in this active fraction. These results have important implications for the development of new immunotherapeutic approaches for prevention/treatment of TB. PMID: 27297390 [PubMed - as supplied by publisher]

Metabolic connectivity mapping reveals effective connectivity in the resting human brain.

Wed, 15/06/2016 - 14:02
Related Articles Metabolic connectivity mapping reveals effective connectivity in the resting human brain. Proc Natl Acad Sci U S A. 2016 Jan 12;113(2):428-33 Authors: Riedl V, Utz L, Castrillón G, Grimmer T, Rauschecker JP, Ploner M, Friston KJ, Drzezga A, Sorg C Abstract Directionality of signaling among brain regions provides essential information about human cognition and disease states. Assessing such effective connectivity (EC) across brain states using functional magnetic resonance imaging (fMRI) alone has proven difficult, however. We propose a novel measure of EC, termed metabolic connectivity mapping (MCM), that integrates undirected functional connectivity (FC) with local energy metabolism from fMRI and positron emission tomography (PET) data acquired simultaneously. This method is based on the concept that most energy required for neuronal communication is consumed postsynaptically, i.e., at the target neurons. We investigated MCM and possible changes in EC within the physiological range using "eyes open" versus "eyes closed" conditions in healthy subjects. Independent of condition, MCM reliably detected stable and bidirectional communication between early and higher visual regions. Moreover, we found stable top-down signaling from a frontoparietal network including frontal eye fields. In contrast, we found additional top-down signaling from all major clusters of the salience network to early visual cortex only in the eyes open condition. MCM revealed consistent bidirectional and unidirectional signaling across the entire cortex, along with prominent changes in network interactions across two simple brain states. We propose MCM as a novel approach for inferring EC from neuronal energy metabolism that is ideally suited to study signaling hierarchies in the brain and their defects in brain disorders. PMID: 26712010 [PubMed - indexed for MEDLINE]

Plants Possess a Cyclic Mitochondrial Metabolic Pathway similar to the Mammalian Metabolic Repair Mechanism Involving Malate Dehydrogenase and l-2-Hydroxyglutarate Dehydrogenase.

Wed, 15/06/2016 - 14:02
Related Articles Plants Possess a Cyclic Mitochondrial Metabolic Pathway similar to the Mammalian Metabolic Repair Mechanism Involving Malate Dehydrogenase and l-2-Hydroxyglutarate Dehydrogenase. Plant Cell Physiol. 2015 Sep;56(9):1820-30 Authors: Hüdig M, Maier A, Scherrers I, Seidel L, Jansen EE, Mettler-Altmann T, Engqvist MK, Maurino VG Abstract Enzymatic side reactions can give rise to the formation of wasteful and toxic products that are removed by metabolite repair pathways. In this work, we identify and characterize a mitochondrial metabolic repair mechanism in Arabidopsis thaliana involving malate dehydrogenase (mMDH) and l-2-hydroxyglutarate dehydrogenase (l-2HGDH). We analyze the kinetic properties of both A. thaliana mMDH isoforms, and show that they produce l-2-hydroxyglutarate (l-2HG) from 2-ketoglutarate (2-KG) at low rates in side reactions. We identify A. thaliana l-2HGDH as a mitochondrial FAD-containing oxidase that converts l-2HG back to 2-KG. Using loss-of-function mutants, we show that the electrons produced in the l-2HGDH reaction are transferred to the mitochondrial electron transport chain through the electron transfer protein (ETF). Thus, plants possess the biochemical components of an l-2HG metabolic repair system identical to that found in mammals. While deficiencies in the metabolism of l-2HG result in fatal disorders in mammals, accumulation of l-2HG in plants does not adversely affect their development under a range of tested conditions. However, orthologs of l-2HGDH are found in all examined genomes of viridiplantae, indicating that the repair reaction we identified makes an essential contribution to plant fitness in as yet unidentified conditions in the wild. PMID: 26203119 [PubMed - indexed for MEDLINE]

Smoking-Associated Disordering of the Airway Basal Stem/Progenitor Cell Metabotype.

Wed, 15/06/2016 - 14:02
Related Articles Smoking-Associated Disordering of the Airway Basal Stem/Progenitor Cell Metabotype. Am J Respir Cell Mol Biol. 2016 Feb;54(2):231-40 Authors: Deeb RS, Walters MS, Strulovici-Barel Y, Chen Q, Gross SS, Crystal RG Abstract The airway epithelium is a complex pseudostratified multicellular layer lining the tracheobronchial tree, functioning as the primary defense against inhaled environmental contaminants. The major cell types of the airway epithelium include basal, intermediate columnar, ciliated, and secretory. Basal cells (BCs) are the proliferating stem/progenitor population that differentiate into the other specialized cell types of the airway epithelium during normal turnover and repair. Given that cigarette smoke delivers thousands of xenobiotics and high levels of reactive molecules to the lung epithelial surface, we hypothesized that cigarette smoke broadly perturbs BC metabolism. To test this hypothesis, primary airway BCs were isolated from healthy nonsmokers (n = 11) and healthy smokers (n = 7) and assessed by global metabolic profiling by liquid chromatography-mass spectrometry. The analysis identified 52 significant metabolites in BCs differentially expressed between smokers and nonsmokers (P < 0.05). These changes included metabolites associated with redox pathways, energy production, and inflammatory processes. Notably, BCs from smokers exhibited altered levels of the key enzyme cofactors/substrates nicotinamide adenine dinucleotide, flavin adenine dinucleotide, acetyl coenzyme A, and membrane phospholipid levels. Consistent with the high burden of oxidants in cigarette smoke, glutathione levels were diminished, whereas 3-nitrotyrosine levels were increased, suggesting that protection of airway epithelial cells against oxidative and nitrosative stress is significantly compromised in smoker BCs. It is likely that this altered metabotype is a reflection of, and likely contributes to, the disordered biology of airway BCs consequent to the stress cigarette smoking puts on the airway epithelium. PMID: 26161876 [PubMed - indexed for MEDLINE]

Kinesin-1 promotes post-Golgi trafficking of NCAM140 and NCAM180 to the cell surface.

Wed, 15/06/2016 - 14:02
Related Articles Kinesin-1 promotes post-Golgi trafficking of NCAM140 and NCAM180 to the cell surface. J Cell Sci. 2015 Aug 1;128(15):2816-29 Authors: Wobst H, Schmitz B, Schachner M, Diestel S, Leshchyns'ka I, Sytnyk V Abstract The neural cell adhesion molecule (NCAM, also known as NCAM1) is important during neural development, because it contributes to neurite outgrowth in response to its ligands at the cell surface. In the adult brain, NCAM is involved in regulating synaptic plasticity. The molecular mechanisms underlying delivery of NCAM to the neuronal cell surface remain poorly understood. We used a protein macroarray and identified the kinesin light chain 1 (KLC1), a component of the kinesin-1 motor protein, as a binding partner of the intracellular domains of the two transmembrane isoforms of NCAM, NCAM140 and NCAM180. KLC1 binds to amino acids CGKAGPGA within the intracellular domain of NCAM and colocalizes with kinesin-1 in the Golgi compartment. Delivery of NCAM180 to the cell surface is increased in CHO cells and neurons co-transfected with kinesin-1. We further demonstrate that the p21-activated kinase 1 (PAK1) competes with KLC1 for binding to the intracellular domain of NCAM and contributes to the regulation of the membrane insertion of NCAM. Our results indicate that NCAM is delivered to the cell surface through a kinesin-1-mediated transport mechanism in a PAK1-dependent manner. PMID: 26101351 [PubMed - indexed for MEDLINE]

Metabolomic quality control of commercial Asian ginseng, and cultivated and wild American ginseng using (1)H NMR and multi-step PCA.

Wed, 15/06/2016 - 14:02
Related Articles Metabolomic quality control of commercial Asian ginseng, and cultivated and wild American ginseng using (1)H NMR and multi-step PCA. J Pharm Biomed Anal. 2015 Oct 10;114:113-20 Authors: Zhao H, Xu J, Ghebrezadik H, Hylands PJ Abstract Ginseng, mainly Asian ginseng and American ginseng, is the most widely consumed herbal product in the world . However, the existing quality control method is not adequate: adulteration is often seen in the market. In this study, 31 batches of ginseng from Chinese stores were analyzed using (1)H NMR metabolite profiles together with multi-step principal component analysis. The most abundant metabolites, sugars, were excluded from the NMR spectra after the first principal component analysis, in order to reveal differences contributed by less abundant metabolites. For the first time, robust, distinctive and representative differences of Asian ginseng from American ginseng were found and the key metabolites responsible were identified as sucrose, glucose, arginine, choline, and 2-oxoglutarate and malate. Differences between wild and cultivated ginseng were identified as ginsenosides. A substitute cultivated American ginseng was noticed. These results demonstrated that the combination of (1)H NMR and PCA is effective in quality control of ginseng. PMID: 26037159 [PubMed - indexed for MEDLINE]

Mitophagy-driven mitochondrial rejuvenation regulates stem cell fate.

Tue, 14/06/2016 - 16:07
Related Articles Mitophagy-driven mitochondrial rejuvenation regulates stem cell fate. Aging (Albany NY). 2016 Jun 13; Authors: Vazquez-Martin A, Van den Haute C, Cufí S, Corominas-Faja B, Cuyàs E, Lopez-Bonet E, Rodriguez-Gallego E, Fernández-Arroyo S, Joven J, Baekelandt V, Menendez JA Abstract Our understanding on how selective mitochondrial autophagy, or mitophagy, can sustain the archetypal properties of stem cells is incomplete. PTEN-induced putative kinase 1 (PINK1) plays a key role in the maintenance of mitochondrial morphology and function and in the selective degradation of damaged mitochondria by mitophagy. Here, using embryonic fibroblasts fromPINK1 gene-knockout (KO) mice, we evaluated whether mitophagy is a causal mechanism for the control of cell-fate plasticity and maintenance of pluripotency. Loss of PINK1-dependent mitophagy was sufficient to dramatically decrease the speed and efficiency of induced pluripotent stem cell (iPSC) reprogramming. Mitophagy-deficient iPSC colonies, which were characterized by a mixture of mature and immature mitochondria, seemed unstable, with a strong tendency to spontaneously differentiate and form heterogeneous populations of cells. Although mitophagy-deficient iPSC colonies normally expressed pluripotent markers, functional monitoring of cellular bioenergetics revealed an attenuated glycolysis in mitophagy-deficient iPSC cells. Targeted metabolomics showed a notable alteration in numerous glycolysis- and TCA-related metabolites in mitophagy-deficient iPSC cells, including a significant decrease in the intracellular levels of α-ketoglutarate -a key suppressor of the differentiation path in stem cells. Mitophagy-deficient iPSC colonies exhibited a notably reduced teratoma-initiating capacity, but fully retained their pluripotency and multi-germ layer differentiation capacity in vivo. PINK1-dependent mitophagy pathway is an important mitochondrial switch that determines the efficiency and quality of somatic reprogramming. Mitophagy-driven mitochondrial rejuvenation might contribute to the ability of iPSCs to suppress differentiation by directing bioenergetic transition and metabolome remodeling traits. These findings provide new insights into how mitophagy might influence the stem cell decisions to retain pluripotency or differentiate in tissue regeneration and aging, tumor growth, and regenerative medicine. PMID: 27295498 [PubMed - as supplied by publisher]

Metabolomics as a Challenging Approach for Medicinal Chemistry and Personalized Medicine.

Tue, 14/06/2016 - 16:07
Related Articles Metabolomics as a Challenging Approach for Medicinal Chemistry and Personalized Medicine. J Med Chem. 2016 Jun 13; Authors: Frederich M, Pirotte B, Fillet M, De Tullio P Abstract "Omics" sciences have been developed to provide a holistic point of view of biology and to better understand the complexity of an organism as a whole. These systems biology approaches can be examined at different levels, starting from the most fundamental, i.e., the genome, and finishing with the most functional, i.e., the metabolome. Similar to how genomics is applied to the exploration of DNA, metabolomics is the qualitative and quantitative study of metabolites. This emerging field is clearly linked to genomics, transcriptomics and proteomics. In addition, metabolomics provides a unique and direct vision of the functional outcome of an organism's activities that are required for it to survive, grow and respond to internal and external stimuli or stress, e.g., pathologies and drugs. The links between metabolic changes, patient phenotype, physiological and/or pathological status and treatment are now well established and have opened a new area for the application of metabolomics in the drug discovery process and in personalized medicine. PMID: 27295417 [PubMed - as supplied by publisher]

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