PubMed

The natural variance of the Arabidopsis floral secondary metabolites. Sci Data. 2018 Apr 03;5:180051 Authors: Tohge T, Borghi M, Fernie AR Abstract Application of mass spectrometry-based metabolomics enables the detection of genotype-related natural variance in metabolism. Differences in secondary metabolite composition of flowers of 64 Arabidopsis thaliana (Arabidopsis) natural accessions, representing a considerable portion of the natural variation in this species are presented. The raw metabolomic data of the accessions and reference extracts derived from flavonoid knockout mutants have been deposited in the MetaboLights database. Additionally, summary tables of floral secondary metabolite data are presented in this article to enable efficient re-use of the dataset either in metabolomics cross-study comparisons or correlation-based integrative analysis of other metabolomic and phenotypic features such as transcripts, proteins and growth and flowering related phenotypes. PMID: 29611844 [PubMed - in process]

Chemometrics Strategies for Peak Detection and Profiling from Multidimensional Chromatography. Proteomics. 2018 Apr 03;:e1700327 Authors: Navarro-Reig M, Bedia C, Tauler R, Jaumot J Abstract The increasing complexity of omics research has encouraged the development of new instrumental technologies able to deal with these challenging samples. In this way, the rise of multidimensional separations should be highlighted due to the massive amounts of information that provide with an enhanced analyte determination. Both proteomics and metabolomics benefit from this higher separation capacity achieved when different chromatographic dimensions are combined, either in LC or GC. However, this vast quantity of experimental information requires the application of chemometric data analysis strategies to retrieve this hidden knowledge, especially in the case of non-targeted studies. In this work, we review the most common chemometric tools and approaches for the analysis of this multidimensional chromatographic data. First, different options for data preprocessing and enhancement of the instrumental signal are introduced. Next, the most used chemometric methods for the detection of chromatographic peaks and the resolution of chromatographic and spectral contributions (profiling) are presented. The description of these data analysis approaches is complemented with enlightening examples from omics fields that demonstrate the exceptional potential of the combination of multidimensional separation techniques and chemometrics tools of data analysis. This article is protected by copyright. All rights reserved. PMID: 29611629 [PubMed - as supplied by publisher]

Related Articles Metabolomics Study of Immune Responses of New Zealand Greenshell™ Mussels (Perna canaliculus) Infected with Pathogenic Vibrio sp. Mar Biotechnol (NY). 2018 Apr 02;: Authors: Nguyen TV, Alfaro AC, Young T, Ravi S, Merien F Abstract Vibrio coralliilyticus is a bacterial pathogen which can affect a range of marine organisms, such as corals, fish and shellfish, with sometimes devastating consequences. However, little is known about the mechanisms involved in the host-pathogen interaction, especially within molluscan models. We applied gas chromatography-mass spectrometry (GC-MS)-based metabolomics to characterize the physiological responses in haemolymph of New Zealand Greenshell™ mussels (Perna canaliculus) injected with Vibrio sp. DO1 (V. coralliilyticus/neptunius-like isolate). Univariate data analyses of metabolite profiles in Vibrio-exposed mussels revealed significant changes in 22 metabolites at 6 h post-infection, compared to non-exposed mussels. Among them, 10 metabolites were up-regulated, while 12 metabolites were down-regulated in infected mussels. Multivariate analyses showed a clear distinction between infected and non-infected mussels. In addition, secondary pathway analyses indicated perturbations of the host innate immune system following infection, including oxidative stress, inflammation and disruption of the TCA cycle, change in amino acid metabolism and protein synthesis. These findings provide new insights into the pathogenic mechanisms of Vibrio infection of mussels and demonstrate our ability to detect detailed and rapid host responses from haemolymph samples using a metabolomics approach. PMID: 29611031 [PubMed - as supplied by publisher]

Related Articles Observation of acetyl phosphate formation in mammalian mitochondria using real-time in-organelle NMR metabolomics. Proc Natl Acad Sci U S A. 2018 Apr 02;: Authors: Xu WJ, Wen H, Kim HS, Ko YJ, Dong SM, Park IS, Yook JI, Park S Abstract Recent studies point out the link between altered mitochondrial metabolism and cancer, and detailed understanding of mitochondrial metabolism requires real-time detection of its metabolites. Employing heteronuclear 2D NMR spectroscopy and 13C3-pyruvate, we propose in-organelle metabolomics that allows for the monitoring of mitochondrial metabolic changes in real time. The approach identified acetyl phosphate from human mitochondria, whose production has been largely neglected in eukaryotic metabolism since its first description about 70 years ago in bacteria. The kinetic profile of acetyl phosphate formation was biphasic, and its transient nature suggested its role as a metabolic intermediate. The method also allowed for the estimation of pyruvate dehydrogenase (PDH) enzyme activity through monitoring of the acetyl-CoA formation, independent of competing cytosolic metabolism. The results confirmed the positive regulation of mitochondrial PDH activity by p53, a well-known tumor suppressor. Our approach can easily be applied to other organelle-specific metabolic studies. PMID: 29610354 [PubMed - as supplied by publisher]

Related Articles Cardiac Dysfunction and Metabolic Inflexibility in a Mouse Model of Diabetes Without Dyslipidaemia. Diabetes. 2018 Apr 02;: Authors: Rohm M, Savic D, Ball V, Curtis MK, Bonham S, Fischer R, Legrave N, MacRae JI, Tyler DJ, Ashcroft FM Abstract Diabetes is a well-established risk factor for heart disease leading to impaired cardiac function and a metabolic switch towards fatty acid usage. Here, we investigated if hyperglycaemia/hypoinsulinaemia in the absence of dyslipidaemia is sufficient to drive these changes, and if they can be reversed by restoring euglycaemia. Using the βV59M mouse model, in which diabetes can be rapidly induced and reversed, we show that stroke volume and cardiac output were reduced within two weeks of diabetes induction. Flux through pyruvate dehydrogenase was decreased, as measured in vivo by hyperpolarized [1-13C]pyruvate magnetic resonance spectroscopy. Metabolomics showed accumulation of pyruvate, lactate, alanine, TCA cycle metabolites, and branched chain amino acids. Myristic and palmitoleic acid were decreased. Proteomics revealed proteins involved in fatty acid metabolism were increased whereas those involved in glucose metabolism decreased. Western blotting showed enhanced pyruvate dehydrogenase kinase 4 (PDK4) and uncoupling protein 3 (UCP3) expression. Elevated PDK4 and UCP3 and reduced pyruvate usage were present 24 hr after diabetes induction. The observed effects were independent of dyslipidaemia, as mice showed no evidence of elevated serum triglycerides or lipid accumulation in peripheral organs (including heart). The effects of diabetes were reversible, as glibenclamide therapy restored euglycaemia, cardiac metabolism and function, and PDK4/UCP3 levels. PMID: 29610263 [PubMed - as supplied by publisher]

A comparative proteomic characterization and nutritional assessment of naturally- and artificially-cultivated Cordyceps sinensis. J Proteomics. 2018 Mar 30;: Authors: Zhang X, Liu Q, Zhou W, Li P, Alolga RN, Qian Z, Li W, Qi LW, Yin X Abstract Cordyceps sinensis has gained increasing attention due to its nutritional and medicinal properties. Herein, we employed label-free quantitative mass spectrometry to explore the proteome differences between naturally- and artificially-cultivated C. sinensis. A total of 22,829 peptides with confidence ≥95%, corresponding to 2541 protein groups were identified from the caterpillar bodies/stromata of 12 naturally- and artificially-cultivated samples of C. sinensis. Among them, 341 proteins showed significant differences between the samples of natural and artificial cultivation. These proteins were mainly involved in energy production/conversion, amino acid transport/metabolism, and transcription regulation. The proteomic results were confirmed by the identification of 4 significantly changed metabolites, thus, lysine, threonine, serine, and arginine via untargeted metabolomics. The change tendencies of these metabolites were partly in accordance with changes in abundance of the proteins, which was upstream of their synthetic pathways. In addition, the nutritional value in terms of the levels of nucleosides, nucleotides, and adenosine between the artificially- and naturally-cultivated samples was virtually same. These proteomic data will be useful for understanding the medicinal value of C. sinensis and serve as reference for its artificial cultivation. SIGNIFICANCE: C. sinensis is a precious and valued medicinal product, the current basic proteome dataset would provide useful information to understand its development/infection processes as well as help to artificially cultivate it. This work would also provide basic proteome profile for further study of C. sinensis. PMID: 29609095 [PubMed - as supplied by publisher]

MetaboCraft: Building a Minecraft plugin for metabolomics. Bioinformatics. 2018 Mar 28;: Authors: Megalios A, Daly R, Burgess K Abstract Motivation: The rapid advances in metabolomics pose a significant challenge in presentation and interpretation of results. Development of new, engaging visual aids is crucial to advancing our understanding of new findings. Results: We have developed MetaboCraft, a Minecraft plugin which creates immersive visualisations of metabolic networks and pathways in a 3-D environment and allows the results of user experiments to be viewed in this context, presenting a novel approach to exploring the metabolome. Availability and implementation: https://github.com/argymeg/MetaboCraft/; https://hub.docker.com/r/ronandaly/metabocraft/. Contact: karl.burgess@glasgow.ac.uk. Supplementary information: Supplementary data are available at Bioinformatics online. PMID: 29608638 [PubMed - as supplied by publisher]

Targeted and non-targeted metabolite identification of MAM-2201 in human, mouse, and rat hepatocytes. Drug Test Anal. 2018 Apr 02;: Authors: Kim JH, Kong TY, Moon JY, Choi KH, Cho YY, Kang HC, Lee JY, Lee HS Abstract MAM-2201 is a fluorinated naphthoylindole synthetic cannabinoid with potent psychoactive properties that has been detected as an active ingredient in herbal incense blends. To gain a greater understanding of MAM-2201 metabolism and to compare the metabolic fate in humans with those in animals, the metabolism of MAM-2201 in human, mouse, and rat hepatocytes was investigated using liquid chromatography-high-resolution mass spectrometry combined with targeted and non-targeted metabolite profiling approaches. Nineteen phase I metabolites (M1-M19) reported previously in human liver microsomes and 13 novel metabolites were identified in human, mouse, and rat hepatocytes: one phase I metabolite (M20) and 12 phase II metabolites including six glucuronides (G1-G6), one sulfate (S1), and five glutathione (GSH) conjugates (GS1-GS5) of MAM-2201 metabolites. G3 was human-specific, but M20, G1, G2, and 5 GSH conjugates were rat-specific, indicating species-related differences in MAM-2201 metabolism. The findings in the present study can be useful for the experimental design and assessment of metabolism-mediated toxic risk of MAM-2201. PMID: 29608249 [PubMed - as supplied by publisher]

Investigation of Metabolomic Changes in Sunitinib-Resistant Human Renal Carcinoma 786-O Cells by Capillary Electrophoresis-Time of Flight Mass Spectrometry. Biol Pharm Bull. 2018;41(4):619-627 Authors: Hatakeyama H, Fujiwara T, Sato H, Terui A, Hisaka A Abstract Acquired resistance to sunitinib is a challenge in the treatment of renal cell carcinoma (RCC). The dysregulation of cellular metabolism is prevalent during resistance acquisition. It is known that in sunitinib-resistant RCC 786-O (786-O Res) cells sunitinib is mainly sequestered in the intracellular lysosomes. However, the relevance between sunitinib resistance and cellular metabolism has not been examined. In this study, we examined the metabolic changes in 786-O Res by using capillary electrophoresis-time of flight mass spectrometry. The cell line 786-O Res was established via persistent treatment with sunitinib, where increase in intracellular sunitinib, and sizes of lysosomes and nuclei were enhanced as compared with those in the parental 786-O (786-O Par) cells. Metabolic analyses revealed that out of the 110 metabolites examined, 13 were up-regulated and 4 were down-regulated in the 786-O Res cells. The glycolysis, tricarboxylic acid cycle and pentose phosphate pathway (PPP) were identified as being altered in the sunitinib-resistant cells, which resulted in the enhanced metabolisms of energy, nucleic acids, and glutathione redox cycle. As sunitinib was sequestered in the enlarged lysosomes in 786-O Res, the enriched energy metabolism might contribute to the maintenance of luminal pH in lysosomes via the H+ ATPase. The changes in the PPP could contribute to nuclei enlargement through up-regulation of nucleic acid biosynthesis and protect 786-O Res from cytotoxicity induced by sunitinib through up-regulation of reduced glutathione. Though the direct link between sunitinib resistance and metabolic alternation remains to be elucidated, this metabolomics study provides fundamental insights into acquisition of sunitinib resistance. PMID: 29607935 [PubMed - in process]

Lower Concentrations of Circulating Medium and Long Chain Acylcarnitines Characterize Insulin Resistance in Persons with HIV. AIDS Res Hum Retroviruses. 2018 Apr 01;: Authors: Bailin S, Jenkins C, Petucci C, Culver JA, Shepherd BE, Fessel JP, Hulgan T, Koethe JR Abstract In HIV-negative individuals, a plasma metabolite profile characterized by higher levels of branched-chain amino acids (BCAA), aromatic amino acids, and C3/C5 acylcarnitines is associated with insulin resistance and increased risk of diabetes. We sought to characterize the metabolite profile accompanying insulin resistance in HIV-positive persons to assess whether the same or different bioenergetics pathways might be implicated. We performed an observational cohort study of 70 non-diabetic, HIV-positive individuals (50% with body mass index ≥ 30 kg/m2) on efavirenz, tenofovir, and emtricitabine with suppressed HIV-1 RNA levels (< 50 copies/mL) for at least 2 years and a CD4+ count over 350 cells/µL. We measured fasting insulin resistance using the homeostatic model assessment 2, plasma free fatty acids using gas chromatography, and amino acids, acylcarnitines, and organic acids using liquid chromatography/mass spectrometry. We assessed the relationship of plasma metabolites with insulin resistance using multivariable linear regression. The median age was 45 years, median CD4+ count was 701 cells/µL, and median hemoglobin A1c was 5.2%. Insulin resistance was associated with higher plasma C3 acylcarnitines (p=0.01), but not BCAA or C5 acylcarnitines. Insulin resistance was also associated with lower levels of C18, C16, C12, and C2 acylcarnitines (p≤0.03 for all), and lower C18 and C16 acylcarnitine:free fatty acid ratios (p=0.002, and p=0.03, respectively). Insulin resistance in HIV-positive persons is characterized by lower levels of plasma acylcarnitines, including the C2 product of complete fatty acid oxidation, suggesting impaired fatty acid uptake and/or oxidation is a central feature of glucose intolerance in this population. PMID: 29607651 [PubMed - as supplied by publisher]

Urinary Metabolomic Study of Chlorogenic Acid in a Rat Model of Chronic Sleep Deprivation Using Gas Chromatography-Mass Spectrometry. Int J Genomics. 2018;2018:1361402 Authors: Ma WN, Zhou MM, Gou XJ, Zhao L, Cen F, Xu Y, Shen HY Abstract The urinary metabolomic study based on gas chromatography-mass spectrometry (GC-MS) had been developed to investigate the possible antidepressant mechanism of chlorogenic acid (CGA) in a rat model of sleep deprivation (SD). According to pattern recognition analysis, there was a clear separation among big platform group (BP), sleep deprivation group (SD), and the CGA (model + CGA), and CGA group was much closer to the BP group by showing a tendency of recovering towards BP group. Thirty-six significantly changed metabolites related to antidepressant by CGA were identified and used to explore the potential mechanism. Combined with the result of the classic behavioral tests and biochemical indices, CGA has significant antidepressant effects in a rat model of SD, suggesting that the mechanism of action of CGA might be involved in regulating the abnormal pathway of nicotinate and nicotinamide metabolism; glyoxylate and dicarboxylate metabolism; glycine, serine, and threonine metabolism; and arginine and proline metabolism. Our results also show that metabolomics analysis based on GC-MS is a useful tool for exploring biomarkers involved in depression and elucidating the potential therapeutic mechanisms of Chinese medicine. PMID: 29607310 [PubMed]

Bayesian estimation of the number of protonation sites for urinary metabolites from NMR spectroscopic data. Metabolomics. 2018;14(5):56 Authors: Ye L, De Iorio M, Ebbels TMD Abstract Introduction: To aid the development of better algorithms for [Formula: see text]H NMR data analysis, such as alignment or peak-fitting, it is important to characterise and model chemical shift changes caused by variation in pH. The number of protonation sites, a key parameter in the theoretical relationship between pH and chemical shift, is traditionally estimated from the molecular structure, which is often unknown in untargeted metabolomics applications. Objective: We aim to use observed NMR chemical shift titration data to estimate the number of protonation sites for a range of urinary metabolites. Methods: A pool of urine from healthy subjects was titrated in the range pH 2-12, standard [Formula: see text]H NMR spectra were acquired and positions of 51 peaks (corresponding to 32 identified metabolites) were recorded. A theoretical model of chemical shift was fit to the data using a Bayesian statistical framework, using model selection procedures in a Markov Chain Monte Carlo algorithm to estimate the number of protonation sites for each molecule. Results: The estimated number of protonation sites was found to be correct for 41 out of 51 peaks. In some cases, the number of sites was incorrectly estimated, due to very close pKa values or a limited amount of data in the required pH range. Conclusions: Given appropriate data, it is possible to estimate the number of protonation sites for many metabolites typically observed in [Formula: see text]H NMR metabolomics without knowledge of the molecular structure. This approach may be a valuable resource for the development of future automated metabolite alignment, annotation and peak fitting algorithms. PMID: 29606928 [PubMed]

Trans-Fats Inhibit Autophagy Induced by Saturated Fatty Acids. EBioMedicine. 2018 Mar 27;: Authors: Sauvat A, Chen G, Müller K, Tong M, Aprahamian F, Durand S, Cerrato G, Bezu L, Leduc M, Franz J, Rockenfeller P, Sadoshima J, Madeo F, Kepp O, Kroemer G Abstract Depending on the length of their carbon backbone and their saturation status, natural fatty acids have rather distinct biological effects. Thus, longevity of model organisms is increased by extra supply of the most abundant natural cis-unsaturated fatty acid, oleic acid, but not by that of the most abundant saturated fatty acid, palmitic acid. Here, we systematically compared the capacity of different saturated, cis-unsaturated and alien (industrial or ruminant) trans-unsaturated fatty acids to provoke cellular stress in vitro, on cultured human cells expressing a battery of distinct biosensors that detect signs of autophagy, Golgi stress and the unfolded protein response. In contrast to cis-unsaturated fatty acids, trans-unsaturated fatty acids failed to stimulate signs of autophagy including the formation of GFP-LC3B-positive puncta, production of phosphatidylinositol-3-phosphate, and activation of the transcription factor TFEB. When combined effects were assessed, several trans-unsaturated fatty acids including elaidic acid (the trans-isomer of oleate), linoelaidic acid, trans-vaccenic acid and palmitelaidic acid, were highly efficient in suppressing autophagy and endoplasmic reticulum stress induced by palmitic, but not by oleic acid. Elaidic acid also inhibited autophagy induction by palmitic acid in vivo, in mouse livers and hearts. We conclude that the well-established, though mechanistically enigmatic toxicity of trans-unsaturated fatty acids may reside in their capacity to abolish cytoprotective stress responses induced by saturated fatty acids. PMID: 29606629 [PubMed - as supplied by publisher]

Application of sequential and orthogonalised-partial least squares (SO-PLS) regression to predict sensory properties of Cabernet Sauvignon wines from grape chemical composition. Food Chem. 2018 Aug 01;256:195-202 Authors: Niimi J, Tomic O, Næs T, Jeffery DW, Bastian SEP, Boss PK Abstract The current study determined the applicability of sequential and orthogonalised-partial least squares (SO-PLS) regression to relate Cabernet Sauvignon grape chemical composition to the sensory perception of the corresponding wines. Grape samples (n = 25) were harvested at a similar maturity and vinified identically in 2013. Twelve measures using various (bio)chemical methods were made on grapes. Wines were evaluated using descriptive analysis with a trained panel (n = 10) for sensory profiling. Data was analysed globally using SO-PLS for the entire sensory profiles (SO-PLS2), as well as for single sensory attributes (SO-PLS1). SO-PLS1 models were superior in validated explained variances than SO-PLS2. SO-PLS provided a structured approach in the selection of predictor chemical data sets that best contributed to the correlation of important sensory attributes. This new approach presents great potential for application in other explorative metabolomics studies of food and beverages to address factors such as quality and regional influences. PMID: 29606438 [PubMed - in process]

Related Articles Chemical profiling of two congeneric sea mat corals along the Brazilian coast: adaptive and functional patterns. Chem Commun (Camb). 2018 Feb 20;54(16):1952-1955 Authors: Costa-Lotufo LV, Carnevale-Neto F, Trindade-Silva AE, Silva RR, Silva GGZ, Wilke DV, Pinto FCL, Sahm BDB, Jimenez PC, Mendonça JN, Lotufo TMC, Pessoa ODL, Lopes NP Abstract Metabolomic profiles were explored to understand environmental and taxonomic influences on the metabolism of two congeneric zoanthids, Palythoa caribaeorum and P. variabilis, collected across distinct geographical ranges. Integrated mass spectrometry data suggested the major influence of geographical location on chemical divergence when compared to species differentiation. PMID: 29323379 [PubMed - indexed for MEDLINE]

Related Articles Beyond COX-1: the effects of aspirin on platelet biology and potential mechanisms of chemoprevention. Cancer Metastasis Rev. 2017 Jun;36(2):289-303 Authors: Ornelas A, Zacharias-Millward N, Menter DG, Davis JS, Lichtenberger L, Hawke D, Hawk E, Vilar E, Bhattacharya P, Millward S Abstract After more than a century, aspirin remains one of the most commonly used drugs in western medicine. Although mainly used for its anti-thrombotic, anti-pyretic, and analgesic properties, a multitude of clinical studies have provided convincing evidence that regular, low-dose aspirin use dramatically lowers the risk of cancer. These observations coincide with recent studies showing a functional relationship between platelets and tumors, suggesting that aspirin's chemopreventive properties may result, in part, from direct modulation of platelet biology and biochemistry. Here, we present a review of the biochemistry and pharmacology of aspirin with particular emphasis on its cyclooxygenase-dependent and cyclooxygenase-independent effects in platelets. We also correlate the results of proteomic-based studies of aspirin acetylation in eukaryotic cells with recent developments in platelet proteomics to identify non-cyclooxygenase targets of aspirin-mediated acetylation in platelets that may play a role in its chemopreventive mechanism. PMID: 28762014 [PubMed - indexed for MEDLINE]

Regulation of Kynurenine Metabolism by a Ketogenic Diet. J Lipid Res. 2018 Mar 31;: Authors: Heischmann S, Gano LB, Quinn K, Liang LP, Klepacki J, Christians U, Reisdorph N, Patel M Abstract Ketogenic diets (KDs) are increasingly utilized as treatments for epilepsy, other neurological diseases, and cancer. Despite their long history in suppressing seizures, the distinct molecular mechanisms of action of KDs are still largely unknown. The goal of this study was to identify key metabolites and pathways altered in hippocampus and plasma of rats fed a KD vs. control diet either ad libitum or calorically restricted to 90% of the recommended intake. This was accomplished using a combination of targeted methods and untargeted mass spectrometry-based metabolomics analyses. Various metabolites of and related to the tryptophan degradation pathway, such as kynurenine and kynurenic acid, as well as enzyme cofactors showed significant changes between groups fed different diets and/or calorie amounts in plasma and/or the hippocampus. Kynurenine was significantly downregulated in both matrices in animals of the control diet-calorically restricted, KD-ad libitum, and KD-calorically restricted groups compared to the control diet-ad libitum group. Our data suggest that the tryptophan degradation pathway is a key target of the KD. PMID: 29605816 [PubMed - as supplied by publisher]

Baseline levels of metabolites in different tissues of mussel Mytilus galloprovincialis (Bivalvia: Mytilidae). Comp Biochem Physiol Part D Genomics Proteomics. 2018 Mar 27;26:32-39 Authors: Cappello T, Giannetto A, Parrino V, Maisano M, Oliva S, De Marco G, Guerriero G, Mauceri A, Fasulo S Abstract The Mediterranean mussel Mytilus galloprovincialis (Lamarck 1819) is a popular shellfish commonly included in human diet and is routinely used as bioindicator in environmental monitoring programmes worldwide. Recently, metabolomics has emerged as a powerful tool both in food research and ecotoxicology for monitoring mussels' freshness and assessing the effects of environmental changes. However, there is still a paucity of data on complete metabolic baseline of mussel tissues. To mitigate this knowledge gap, similarities and differences in metabolite profile of digestive gland (DG), gills (G), and posterior adductor muscle (PAM) of aquaculture-farmed M. galloprovincialis were herein investigated by a proton nuclear magnetic resonance (1H NMR)-based metabolomic approach and discussed considering their physiological role. A total of 44 metabolites were identified in mussel tissues and grouped in amino acids, energy metabolites, osmolytes, neurotransmitters, nucleotides, alkaloids, and miscellaneous metabolites. A PCA showed that mussel tissues clustered separately from each other, suggesting a clear differentiation in their metabolic profiles. A Venn diagram revealed that mussel DG, G and PAM shared 27 (61.36%) common metabolites, though with different concentrations. Osmolytes were found to dominate the metabolome of all tissues. The DG exhibited higher level of glutathione and carbohydrates. The G showed greater level of osmolytes and the exclusive presence of neurotransmitters, namely acetylcholine and serotonin. In PAM higher levels of energetics-related metabolites were found. Overall, findings from this study are helpful for a better understanding of mussel tissue-specific physiological functions as well as for future NMR-based metabolomic investigations of marine mussel health and safety. PMID: 29605489 [PubMed - as supplied by publisher]

Related Articles Identification of metabolites in plasma for predicting survival in glioblastoma. Mol Carcinog. 2018 Mar 30;: Authors: Shen J, Song R, Hodges TR, Heimberger AB, Zhao H Abstract Circulating metabolomics profiling holds prognostic potential. However, such efforts have not been extensively carried out in glioblastoma. In this study, two-step (training and testing) metabolomics profiling was conducted from the plasma samples of 159 glioblastoma patients. Metabolomics profiling was tested for correlation with 2-year overall and disease-free survivals. Arginine, methionine, and kynurenate levels were significantly associated with 2-year overall survival in both the training and testing sets. In the combined sets, elevated levels of arginine and methionine were associated with a 34% and 37% increased probability whereas kynurenate was associated with a 55% decreased probability of 2-year overall survival. These three metabolites were also significantly associated with 2-year disease-free survival. Risk scores were generated using the linear combination of levels of these significant metabolites. Glioblastoma patients with a high-risk score exhibited a 2.41-fold decreased probability of 2-year overall survival (hazard ratio (HR) = 2.41; 95% Confidence Interval (CI) = 1.20-4.93) and a 3.17 fold decreased probability of 2-year disease free survival (HR = 3.17, 95% CI = 1.42-7.54) relative to those with a low-risk score. In conclusion, we identified a unique plasma metabolite profile that is predictive of glioblastoma prognosis. This article is protected by copyright. All rights reserved. PMID: 29603794 [PubMed - as supplied by publisher]

Related Articles Changes in Plasma Metabolite Concentrations after a Low-Glycemic Index Diet Intervention. Mol Nutr Food Res. 2018 Mar 30;:e1700975 Authors: Hernández-Alonso P, Giardina S, Cañueto D, Salas-Salvadó J, Cañellas N, Bulló M Abstract SCOPE: To examine whether a low-glycemic index (LGI) diet improves a set of plasma metabolites related to different metabolic diseases and compared to a high-glycemic index (HGI) diet and a low-fat (LF) diet. METHODS AND RESULTS: We conducted a parallel, randomized trial with three intervention diets: a LGI diet, a HGI diet and a LF diet. A total of 122 adult overweight and obese subjects were enrolled in the study for 6 months. Blood samples were collected at baseline and at the end of the intervention. We analyzed the plasma metabolomic profile of 102 subjects using three different approaches: GC/quadrupole-TOF, LC/quadrupole-TOF and NMR. Both univariate and multivariate analysis were performed. Serine levels were significantly higher following the LGI diet compared to both the HGI and LF diets (q = 0.002), whereas leucine (q = 0.015) and valine (q = 0.024) were lower in the LGI diet compared to the LF diet. A set of two sphingomyelins, two lysophosphatidylcholines and six phosphatidylcholines were significantly modulated after the LGI diet compared to the HGI and LF diets (q<0.05). We found significant correlations between changes in plasma amino acids and lipid species with changes in body weight, glucose, insulin and some inflammatory markers. CONCLUSION: Our results suggest that a LGI diet modulates certain circulating amino acids and lipid levels. These findings may explain the health benefits attributed to LGI diets in metabolic diseases such as type 2 diabetes. This article is protected by copyright. All rights reserved. PMID: 29603657 [PubMed - as supplied by publisher]