PubMed

Related Articles Can cyanobacteria serve as a model of plant photorespiration? - a comparative meta-analysis of metabolite profiles. J Exp Bot. 2016 Mar 11; Authors: Orf I, Timm S, Bauwe H, Fernie AR, Hagemann M, Kopka J, Nikoloski Z Abstract Photorespiration is a process that is crucial for the survival of oxygenic phototrophs in environments that favour the oxygenation reaction of Rubisco. While photorespiration is conserved among cyanobacteria, algae, and embryophytes, it evolved to different levels of complexity in these phyla. The highest complexity is found in embryophytes, where the pathway involves four cellular compartments and respective transport processes. The complexity of photorespiration in embryophytes raises the question whether a simpler system, such as cyanobacteria, may serve as a model to facilitate our understanding of the common key aspects of photorespiration. In this study, we conducted a meta-analysis of publicly available metabolite profiles from the embryophyte Arabidopsis thaliana and the cyanobacterium Synechocystis sp. PCC 6803 grown under conditions that either activate or suppress photorespiration. The comparative meta-analysis evaluated the similarity of metabolite profiles, the variability of metabolite pools, and the patterns of metabolite ratios. Our results show that the metabolic signature of photorespiration is in part conserved between the compared model organisms under conditions that favour the oxygenation reaction. Therefore, our findings support the claim that cyanobacteria can serve as prokaryotic models of photorespiration in embryophytes. PMID: 26969741 [PubMed - as supplied by publisher]

Related Articles Comparative analysis of volatile oils in the stems and roots of Ephedra sinica via GC-MS-based plant metabolomics. Chin J Nat Med. 2016 Feb;14(2):133-40 Authors: Lv MY, Sun JB, Wang M, Fan HY, Zhang ZJ, Xu FG Abstract With a great difference in therapeutic effects of Mahuang (MH, the stems of Ephedra sinica) and Mahuanggen (MHG, the roots of Ephedra sinica), chemical differences between MH and MHG should be investigated. In the present study, gas chromatography-mass spectrometry (GC-MS)-based plant metabolomics was employed to compare volatile oil profiles of MH and MHG. The antioxidant activities of volatile oils from MH and MHG were also compared. 32 differential chemical markers were identified according to the variable importance in the projection (VIP) value of orthogonal partial least squares discriminant analysis (OPLS-DA) and P value of Mann-Whitney test. Among them, chemical markers of tetramethylpyrazine (TMP) and α-terpineol were quantified. Their contents were much higher in most MH samples compared with MHG. The antioxidant assay demonstrated that MH had significantly higher free radical-scavenging activity than MHG. Although MH and MHG derived from the same medicinal plant, there was much difference in their volatile oil profiles. MH samples had significantly higher content of two reported pharmacologically important chemical markers of TMP and α-terpineol, which may account for their different antioxidant activities. PMID: 26968679 [PubMed - in process]

Alcohol Consumption-Related Metabolites in Relation to Colorectal Cancer and Adenoma: Two Case-Control Studies Using Serum Biomarkers. PLoS One. 2016;11(3):e0150962 Authors: Troche JR, Mayne ST, Freedman ND, Shebl FM, Guertin KA, Cross AJ, Abnet CC Abstract Alcohol is a known carcinogen that may be associated with colorectal cancer. However, most epidemiologic studies assess alcoholic beverage consumption using self-reported data, leading to potential exposure misclassification. Biomarkers of alcohol consumption may provide an alternative, complementary approach that reduces misclassification and incorporates individual differences in alcohol metabolism. Therefore, we evaluated the relationship between previously identified alcohol consumption-related metabolites and colorectal cancer and adenoma using serum metabolomics data from two studies. Data on colorectal cancer were obtained from a nested case-control study of 502 US adults (252 cases, 250 controls) within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Data on colorectal adenoma were obtained from a case-control study of 197 US adults (120 cases, 77 controls) from the Navy Colon Adenoma Study. Unconditional multivariable logistic regression models were fit to calculate odds ratios (OR) and 95% confidence intervals (CI) for eight alcohol consumption-related metabolites identified in a previous analysis: ethyl glucuronide; 4-androstene-3beta,17beta-diol disulfate 1; 5-alpha-androstan-3beta,17beta-diol disulfate; 16-hydroxypalmitate; bilirubin (E,Z or Z,E); cyclo (-leu-pro); dihomo-linoleate (20:2n6); and palmitoleate (16:1n7). We found no clear association between these alcohol consumption-related metabolites and either endpoint. However, we did observe an inverse association between cyclo (-leu-pro) and colorectal adenoma that was only observed in the highest metabolite quantile (OR 4th vs. 1st Quantile = 0.30, 95% CI: 0.12-0.78; P-trend = 0.047), but no association for colorectal cancer. In conclusion, there were no adverse associations between alcohol consumption-related metabolites and colorectal cancer or adenoma. PMID: 26967509 [PubMed - as supplied by publisher]

Metabolomics profiling in plasma samples from glioma patients correlates with tumor phenotypes. Oncotarget. 2016 Mar 7; Authors: Zhao H, Heimberger AB, Lu Z, Wu X, Hodges TR, Song R, Shen J Abstract BACKGROUND: Tumor-based molecular biomarkers have redefined in the classification gliomas. However, the association of systemic metabolomics with glioma phenotype has not been explored yet. METHODS: In this study, we conducted two-step (discovery and validation) metabolomic profiling in plasma samples from 87 glioma patients. The metabolomics data were tested for correlation with glioma grade (high vs low), glioblastoma (GBM) versus malignant gliomas, and IDH mutation status. RESULTS: Five metabolites, namely uracil, arginine, lactate, cystamine, and ornithine, significantly differed between high- and low-grade glioma patients in both the discovery and validation cohorts. When the discovery and validation cohorts were combined, we identified 29 significant metabolites with 18 remaining significant after adjusting for multiple comparisons. Those 18 significant metabolites separated high- from low-grade glioma patients with 91.1% accuracy. In the pathway analysis, a total of 18 significantly metabolic pathways were identified. Similarly, we identified 2 and 6 metabolites that significantly differed between GBM and non-GBM, and IDH mutation positive and negative patients after multiple comparison adjusting. Those 6 significant metabolites separated IDH1 mutation positive from negative glioma patients with 94.4% accuracy. Three pathways were identified to be associated with IDH mutation status. Within arginine and proline metabolism, levels of intermediate metabolites in creatine pathway were all significantly lower in IDH mutation positive than in negative patients, suggesting an increased activity of creatine pathway in IDH mutation positive tumors. CONCLUSION: Our findings identified metabolites and metabolic pathways that differentiated tumor phenotypes. These may be useful as host biomarker candidates to further help glioma molecular classification. PMID: 26967252 [PubMed - as supplied by publisher]

PIPINO: A Software Package to Facilitate the Identification of Protein-Protein Interactions from Affinity Purification Mass Spectrometry Data. Biomed Res Int. 2016;2016:2891918 Authors: Kalkhof S, Schildbach S, Blumert C, Horn F, von Bergen M, Labudde D Abstract The functionality of most proteins is regulated by protein-protein interactions. Hence, the comprehensive characterization of the interactome is the next milestone on the path to understand the biochemistry of the cell. A powerful method to detect protein-protein interactions is a combination of coimmunoprecipitation or affinity purification with quantitative mass spectrometry. Nevertheless, both methods tend to precipitate a high number of background proteins due to nonspecific interactions. To address this challenge the software Protein-Protein-Interaction-Optimizer (PIPINO) was developed to perform an automated data analysis, to facilitate the selection of bona fide binding partners, and to compare the dynamic of interaction networks. In this study we investigated the STAT1 interaction network and its activation dependent dynamics. Stable isotope labeling by amino acids in cell culture (SILAC) was applied to analyze the STAT1 interactome after streptavidin pull-down of biotagged STAT1 from human embryonic kidney 293T cells with and without activation. Starting from more than 2,000 captured proteins 30 potential STAT1 interaction partners were extracted. Interestingly, more than 50% of these were already reported or predicted to bind STAT1. Furthermore, 16 proteins were found to affect the binding behavior depending on STAT1 phosphorylation such as STAT3 or the importin subunits alpha 1 and alpha 6. PMID: 26966684 [PubMed - in process]

Metabolomic Profiling of Statin Use and Genetic Inhibition of HMG-CoA Reductase. J Am Coll Cardiol. 2016 Mar 15;67(10):1200-10 Authors: Würtz P, Wang Q, Soininen P, Kangas AJ, Fatemifar G, Tynkkynen T, Tiainen M, Perola M, Tillin T, Hughes AD, Mäntyselkä P, Kähönen M, Lehtimäki T, Sattar N, Hingorani AD, Casas JP, Salomaa V, Kivimäki M, Järvelin MR, Davey Smith G, Vanhala M, Lawlor DA, Raitakari OT, Chaturvedi N, Kettunen J, Ala-Korpela M Abstract BACKGROUND: Statins are first-line therapy for cardiovascular disease prevention, but their systemic effects across lipoprotein subclasses, fatty acids, and circulating metabolites remain incompletely characterized. OBJECTIVES: This study sought to determine the molecular effects of statin therapy on multiple metabolic pathways. METHODS: Metabolic profiles based on serum nuclear magnetic resonance metabolomics were quantified at 2 time points in 4 population-based cohorts from the United Kingdom and Finland (N = 5,590; 2.5 to 23.0 years of follow-up). Concentration changes in 80 lipid and metabolite measures during follow-up were compared between 716 individuals who started statin therapy and 4,874 persistent nonusers. To further understand the pharmacological effects of statins, we used Mendelian randomization to assess associations of a genetic variant known to mimic inhibition of HMG-CoA reductase (the intended drug target) with the same lipids and metabolites for 27,914 individuals from 8 population-based cohorts. RESULTS: Starting statin therapy was associated with numerous lipoprotein and fatty acid changes, including substantial lowering of remnant cholesterol (80% relative to low-density lipoprotein cholesterol [LDL-C]), but only modest lowering of triglycerides (25% relative to LDL-C). Among fatty acids, omega-6 levels decreased the most (68% relative to LDL-C); other fatty acids were only modestly affected. No robust changes were observed for circulating amino acids, ketones, or glycolysis-related metabolites. The intricate metabolic changes associated with statin use closely matched the association pattern with rs12916 in the HMGCR gene (R(2) = 0.94, slope 1.00 ± 0.03). CONCLUSIONS: Statin use leads to extensive lipid changes beyond LDL-C and appears efficacious for lowering remnant cholesterol. Metabolomic profiling, however, suggested minimal effects on amino acids. The results exemplify how detailed metabolic characterization of genetic proxies for drug targets can inform indications, pleiotropic effects, and pharmacological mechanisms. PMID: 26965542 [PubMed - in process]

Characterization of chemical-induced sterile inflammation in vitro: application of the model compound ketoconazole in a human hepatic co-culture system. Arch Toxicol. 2016 Mar 10; Authors: Wewering F, Jouy F, Wissenbach DK, Gebauer S, Blüher M, Gebhardt R, Pirow R, von Bergen M, Kalkhof S, Luch A, Zellmer S Abstract Liver injury as a result of a sterile inflammation is closely linked to the activation of immune cells, including macrophages, by damaged hepatocytes. This interaction between immune cells and hepatocytes is as yet not considered in any of the in vitro test systems applied during the generation of new drugs. Here, we established and characterized a novel in vitro co-culture model with two human cell lines, HepG2 and differentiated THP-1. Ketoconazole, an antifungal drug known for its hepatotoxicity, was used as a model compound in the testing of the co-culture. Single cultures of HepG2 and THP-1 cells were studied as controls. Different metabolism patterns of ketoconazole were observed for the single and co-culture incubations as well as for the different cell types. The main metabolite N-deacetyl ketoconazole was found in cell pellets, but not in supernatants of cell cultures. Global proteome analysis showed that the NRF2-mediated stress response and the CXCL8 (IL-8) pathway were induced by ketoconazole treatment under co-culture conditions. The upregulation and ketoconazole-induced secretion of several pro-inflammatory cytokines, including CXCL8, TNF-α and CCL3, was observed in the co-culture system only, but not in single cell cultures. Taking together, we provide evidence that the co-culture model applied might be suitable to serve as tool for the prediction of chemical-induced sterile inflammation in liver tissue in vivo. PMID: 26965496 [PubMed - as supplied by publisher]

Metabolomics Study on the Toxicity of Annona squamosa by Ultraperformance Liquid-Chromatography High-Definition Mass Spectrometry Coupled with Pattern Recognition Approach and Metabolic Pathways Analysis. J Ethnopharmacol. 2016 Mar 7; Authors: Miao YJ, Shi YY, Li FQ, Shan CX, Chen Y, Chen JW, Li X Abstract ETHNOPHARMACOLOGICAL RELEVANCE: Annona squamosa Linn (Annonaceae) is a commonly used and effective traditional Chinese medicine (TCM) especially in the South China. The seeds of Annona squamosa Linn (SAS) have been used as a folk remedy to treat "malignant sores" (cancer) in South of China, but they also have high toxicity on human body. AIM OF THE STUDY: To discover the potential biomarkers in the mice caused by SAS. MATERIALS AND METHODS: We made metabonomics studies on the toxicity of SAS by ultraperformance liquid-chromatography high-definition mass spectrometry coupled with pattern recognition approach and metabolic pathways analysis. RESULTS: The significant difference in metabolic profiles and changes of metabolite biomarkers between the Control group and SAS group were well observed. 11 positive ions and 9 negative ions ((P<0.05)) were indicated based on UFLC-QTOF-HDMS. The metabolic pathways of SAS group are discussed according to the identified endogenous metabolites, and eight metabolic pathways are identified using Kyoto Encyclopedia of Genes and Genomes (KEGG). CONCLUSIONS: The present study demonstrates that metabonomics analysis could greatly facilitate and provide useful information for the further comprehensive understanding of the pharmacological activity and potential toxicity of SAS in the progress of them being designed to a new anti-tumor medicine. PMID: 26965366 [PubMed - as supplied by publisher]

Chemometric methods in data processing of mass spectrometry-based metabolomics: A review. Anal Chim Acta. 2016 Mar 31;914:17-34 Authors: Yi L, Dong N, Yun Y, Deng B, Ren D, Liu S, Liang Y Abstract This review focuses on recent and potential advances in chemometric methods in relation to data processing in metabolomics, especially for data generated from mass spectrometric techniques. Metabolomics is gradually being regarded a valuable and promising biotechnology rather than an ambitious advancement. Herein, we outline significant developments in metabolomics, especially in the combination with modern chemical analysis techniques, and dedicated statistical, and chemometric data analytical strategies. Advanced skills in the preprocessing of raw data, identification of metabolites, variable selection, and modeling are illustrated. We believe that insights from these developments will help narrow the gap between the original dataset and current biological knowledge. We also discuss the limitations and perspectives of extracting information from high-throughput datasets. PMID: 26965324 [PubMed - in process]

Emerging applications of metabolomics in drug discovery and precision medicine. Nat Rev Drug Discov. 2016 Mar 11; Authors: Wishart DS Abstract Metabolomics is an emerging 'omics' science involving the comprehensive characterization of metabolites and metabolism in biological systems. Recent advances in metabolomics technologies are leading to a growing number of mainstream biomedical applications. In particular, metabolomics is increasingly being used to diagnose disease, understand disease mechanisms, identify novel drug targets, customize drug treatments and monitor therapeutic outcomes. This Review discusses some of the latest technological advances in metabolomics, focusing on the application of metabolomics towards uncovering the underlying causes of complex diseases (such as atherosclerosis, cancer and diabetes), the growing role of metabolomics in drug discovery and its potential effect on precision medicine. PMID: 26965202 [PubMed - as supplied by publisher]

Related Articles The oncolytic peptide LTX-315 triggers immunogenic cell death. Cell Death Dis. 2016;7:e2134 Authors: Zhou H, Forveille S, Sauvat A, Yamazaki T, Senovilla L, Ma Y, Liu P, Yang H, Bezu L, Müller K, Zitvogel L, Rekdal Ø, Kepp O, Kroemer G Abstract LTX-315 is a cationic amphilytic peptide that preferentially permeabilizes mitochondrial membranes, thereby causing partially BAX/BAK1-regulated, caspase-independent necrosis. Based on the observation that intratumorally injected LTX-315 stimulates a strong T lymphocyte-mediated anticancer immune response, we investigated whether LTX-315 may elicit the hallmarks of immunogenic cell death (ICD), namely (i) exposure of calreticulin on the plasma membrane surface, (ii) release of ATP into the extracellular space, (iii) exodus of HMGB1 from the nucleus, and (iv) induction of a type-1 interferon response. Using a panel of biosensor cell lines and robotized fluorescence microscopy coupled to automatic image analysis, we observed that LTX-315 induces all known ICD characteristics. This conclusion was validated by several independent methods including immunofluorescence stainings (for calreticulin), bioluminescence assays (for ATP), immunoassays (for HMGB1), and RT-PCRs (for type-1 interferon induction). When injected into established cancers, LTX-315 caused a transiently hemorrhagic focal necrosis that was accompanied by massive release of HMGB1 (from close-to-all cancer cells), as well as caspase-3 activation in a fraction of the cells. LTX-315 was at least as efficient as the positive control, the anthracycline mitoxantrone (MTX), in inducing local inflammation with infiltration by myeloid cells and T lymphocytes. Collectively, these results support the idea that LTX-315 can induce ICD, hence explaining its capacity to mediate immune-dependent therapeutic effects. PMID: 26962684 [PubMed - as supplied by publisher]

Related Articles Intervention Trials with the Mediterranean Diet in Cardiovascular Prevention: Understanding Potential Mechanisms through Metabolomic Profiling. J Nutr. 2016 Mar 9; Authors: Martínez-González MÁ, Ruiz-Canela M, Hruby A, Liang L, Trichopoulou A, Hu FB Abstract Large observational epidemiologic studies and randomized trials support the benefits of a Mediterranean dietary pattern on cardiovascular disease (CVD). Mechanisms postulated to mediate these benefits include the reduction of low-grade inflammation, increased adiponectin concentrations, decreased blood coagulation, enhanced endothelial function, lower oxidative stress, lower concentrations of oxidized LDL, and improved apolipoprotein profiles. However, the metabolic pathways through which the Mediterranean diet influences CVD risk remain largely unknown. Investigating specific mechanisms in the context of a large intervention trial with the use of high-throughput metabolomic profiling will provide more solid public health messages and may help to identify key molecular targets for more effective prevention and management of CVD. Although metabolomics is not without its limitations, the techniques allow for an assessment of thousands of metabolites, providing wide-ranging profiling of small molecules related to biological status. Specific candidate plasma metabolites that may be associated with CVD include branched-chain and aromatic amino acids; the glutamine-to-glutamate ratio; some short- to medium-chain acylcarnitines; gut flora metabolites (choline, betaine, and trimethylamine N-oxide); urea cycle metabolites (citrulline and ornithine); and specific lipid subclasses. In addition to targeted metabolites, the role of a large number of untargeted metabolites should also be assessed. Large intervention trials with the use of food patterns for the prevention of CVD provide an unparalleled opportunity to examine the effects of these interventions on plasma concentrations of specific metabolites and determine whether such changes mediate the benefits of the dietary interventions on CVD risk. PMID: 26962184 [PubMed - as supplied by publisher]

Related Articles Mass spectrometric imaging of metabolites in kidney tissues from rats treated with furosemide. Am J Physiol Renal Physiol. 2016 Mar 9;:ajprenal.00524.2015 Authors: Jung JW, Lee MS, Choi HJ, Jung S, Lee YJ, Hwang GS, Kwon TH Abstract In the kidney, metabolic processes are different among the cortex (COR), outer medulla (OM), and inner medulla (IM). Using matrix-assisted laser desorption/ionization (MALDI) and imaging mass spectrometry (IMS), we examined the change of metabolites in the COR, OM, and IM of the rat kidney after furosemide treatment, compared with vehicle-treated controls. Osmotic minipumps were implanted in male Sprague-Dawley rats to deliver 12 mg/d/rat of furosemide. Vehicle-treated- (n = 14) and furosemide-treated- (furosemide rats, n = 15) rats in metabolic cages received a fixed amount of rat chow (15 g/220 g bw/day/rat) with free access to water intake for 6 days. At day 6, higher urine output (32 ± 4 vs. 9 ± 1 ml/day) and lower urine osmolality (546 ± 44 vs. 1,677 ± 104 mOsm/KgH2O) were observed in furosemide rats. Extracts of COR, OM, and IM were analyzed by UPLC/Q-TOF-MS, where multivariate analysis revealed significant differences between the two groups. Several metabolites, including acetyl carnitine, betaine, carnitine, choline, and glycerophosphorylcholine (GPC), were significantly changed. The changes of metabolites were further identified by MALDI-TOF/TOF and IMS. Their spatial distribution and relative quantitation in the kidneys were analyzed by IMS. Carnitine compounds were increased in COR and IM, whereas carnitine and acetyl carnitine were decreased in OM. Choline compounds were increased in COR and OM, but decreased in IM from furosemide rats. Betaine and GPC were decreased in OM and IM. Taken together, MALDI-TOF/TOF and IMS successfully provide the spatial distribution and relative quantitation of metabolites in the kidney. PMID: 26962105 [PubMed - as supplied by publisher]

Related Articles The variations in the nuclear proteome reveal new transcription factors and mechanisms involved in UV stress response in Pinus radiata. J Proteomics. 2016 Mar 4; Authors: Pascual J, Alegre S, Nagler M, Escandón M, Annacondia ML, Weckwerth W, Valledor L, Cañal MJ Abstract The importance of UV stress and its side-effects over the loss of plant productivity in forest species demands a deeper understanding of how pine trees respond to UV irradiation. Although the response to UV stress has been characterized at system and cellular levels, the dynamics within the nuclear proteome triggered by UV is still unknown despite that they are essential for gene expression and regulation of plant physiology. To fill this gap this work aims to characterize the variations in the nuclear proteome as a response to UV irradiation by using state-of-the-art mass spectrometry-based methods combined with novel bioinformatics workflows. The combination of SEQUEST, de novo sequencing, and novel annotation pipelines allowed cover sensing and transduction pathways, endoplasmic reticulum-related mechanisms and the regulation of chromatin dynamism and gene expression by histones, histone-like NF-Ys, and other transcription factors previously unrelated to this stress source, as well as the role of alternative splicing and other mechanisms involved in RNA translation and protein synthesis. The determination of 33 transcription factors, including NF-YB13, Pp005698_3 (NF-YB) and Pr009668_2 (WD-40), which are correlated to stress responsive mechanisms like an increased accumulation of photoprotective pigments and reduced photosynthesis, pointing them as strong candidate biomarkers for breeding programs aimed to improve UV resistance of pine trees. SIGNIFICANCE: The description of the nuclear proteome of Pinus radiata combining a classic approach based on the use of SEQUEST and the use of a mass accuracy precursor alignment (MAPA) allowed an unprecedented protein coverage. This workflow provided the methodological basis for characterizing the changes in the nuclear proteome triggered by UV irradiation, allowing the depiction of the nuclear events involved in stress response and adaption. The relevance of some of the discovered proteins will suppose a major advance in stress biology field, also providing a set of transcription factors that can be considered as strong biomarker candidates to select trees more tolerant to UV radiation in forest upgrade programs. PMID: 26961940 [PubMed - as supplied by publisher]

Related Articles Decreased hepatic phosphorylated p38 mitogen-activated protein kinase contributes to attenuation of thioacetamide-induced hepatic necrosis in diet-induced obese mice. J Toxicol Sci. 2016;41(2):245-53 Authors: Shirai M, Arakawa S, Teranishi M, Kai K Abstract We previously reported that thioacetamide (TA)-induced hepatocellular necrosis was attenuated in mice fed a high-fat diet (HFD mice) compared with mice fed a normal rodent diet (ND mice). In this study, we investigated whether p38 mitogen-activated protein kinase (p38 MAPK) was involved in this attenuation. Western blot analysis revealed that hepatic phosphorylated p38 MAPK protein decreased at 8 and 24 hours (hr) after TA dosing in the HFD mice, while it decreased only at 24 hr in the ND mice in comparison to the time- and diet-matched, vehicle-treated mice. p38 MAPK regulates various biological functions including inflammation, therefore, hepatic metabolomics analysis focusing on pro-inflammatory lipid mediators was performed. At 24 hr after TA dosing, only one pro-inflammatory mediator, 12-hydroxyeicosatetraenoic acid (HETE), was higher in the HFD mice. On the other hand, in addition to 12-HETE, 15-HETE and 12-hydroxyeicosapentaenoic acid (HEPE) were higher and omega-3/omega-6 polyunsaturated fatty acids ratios were lower in the ND mice at 24 hr. These results of metabolomics indicated that less pro-inflammatory state was seen in HFD mice than in ND mice at 24 hr. Finally, to confirm whether the observed decrease in phosphorylated p38 MAPK could attenuate TA-induced hepatocellular necrosis, we showed that SB203580 hydrochloride, an inhibitor of p38 MAPK, partially attenuated TA-induced hepatic necrosis in ND mice. Collectively, these results suggest that a prompt decrease in phosphorylation of p38 MAPK after TA administration is one of the factors that attenuate TA-induced hepatic necrosis in HFD mice. PMID: 26961609 [PubMed - in process]

Related Articles The urinary metabolomic profile following the intake of meals supplemented with a cocoa extract in middle-aged obese subjects. Food Funct. 2016 Mar 10; Authors: Ibero-Baraibar I, Romo-Hualde A, Gonzalez-Navarro CJ, Zulet MA, Martinez JA Abstract Metabolomics is used to assess the compliance and bioavailability of food components, as well as to evaluate the metabolic changes associated with food consumption. This study aimed to analyze the effect of consuming ready-to-eat meals containing a cocoa extract, within an energy restricted diet on urinary metabolomic changes. Fifty middle-aged volunteers [30.6 (2.3) kg m(-2)] participated in a 4-week randomised, parallel and double-blind study. Half consumed meals supplemented with 1.4 g of cocoa extract (645 mg polyphenols) while the remaining subjects received meals without cocoa supplementation. Ready-to-eat meals were included within a 15% energy restricted diet. Urine samples (24 h) were collected at baseline and after 4 weeks and were analyzed by high-performance-liquid chromatography-time-of-flight-mass-spectrometry (HPLC-TOF-MS) in negative and positive ionization modes followed by multivariate analysis. The relationship between urinary metabolites was evaluated by the Spearman correlation test. Interestingly, the principal component analysis discriminated among the baseline group, control group at the endpoint and cocoa group at the endpoint (p < 0.01), although in the positive ionization mode the baseline and control groups were not well distinguished. Metabolites were related to theobromine metabolism (3-methylxanthine and 3-methyluric acid), food processing (l-beta-aspartyl-l-phenylalanine), flavonoids (2,5,7,3',4'-pentahydroxyflavanone-5-O-glucoside and 7,4'-dimethoxy-6-C-methylflavanone), catecholamine (3-methoxy-4-hydroxyphenylglycol-sulphate) and endogenous metabolism (uridine monophosphate). These metabolites were present in higher (p < 0.001) amounts in the cocoa group. 3-Methylxanthine and l-beta-aspartyl-l-phenylalanine were confirmed with standards. Interestingly, 3-methoxy-4-hydroxyphenylglycol-sulphate was positively correlated with 3-methylxanthine (rho = 0.552; p < 0.001) and 7,4'-dimethoxy-6-C-methylflavanone (rho = 447; p = 0.002). In conclusion, the metabolomic approach supported the compliance of the volunteers with the intervention and suggested the bioavailability of cocoa compounds within the meals. PMID: 26961599 [PubMed - as supplied by publisher]

Related Articles Cerebral Metabolic Profiling of Hypothermic Circulatory Arrest with and Without Antegrade Selective Cerebral Perfusion: Evidence from Nontargeted Tissue Metabolomics in a Rabbit Model. Chin Med J (Engl). 2016 20th Mar;129(6):702-708 Authors: Zou LH, Liu JP, Zhang H, Wu SB, Ji BY Abstract BACKGROUND: Antegrade selective cerebral perfusion (ASCP) is regarded to perform cerebral protection during the thoracic aorta surgery as an adjunctive technique to deep hypothermic circulatory arrest (DHCA). However, brain metabolism profile after ASCP has not been systematically investigated by metabolomics technology. METHODS: To clarify the metabolomics profiling of ASCP, 12 New Zealand white rabbits were randomly assigned into 60 min DHCA with (DHCA+ASCP [DA] group, n = 6) and without ( DHCA [D] group, n = 6) ASCP according to the random number table. ASCP was conducted by cannulation on the right subclavian artery and cross-clamping of the innominate artery. Rabbits were sacrificed 60 min after weaning off cardiopulmonary bypass. The metabolic features of the cerebral cortex were analyzed by a nontargeted metabolic profiling strategy based on gas chromatography-mass spectrometry. Variable importance projection values exceeding 1.0 were selected as potentially changed metabolites, and then Student's t-test was applied to test for statistical significance between the two groups. RESULTS: Metabolic profiling of brain was distinctive significantly between the two groups (Q 2 Y = 0.88 for partial least squares-DA model). In comparing to group D, 62 definable metabolites were varied significantly after ASCP, which were mainly related to amino acid metabolism, carbohydrate metabolism, and lipid metabolism. Kyoto Encyclopedia of Genes and Genomes analysis revealed that metabolic pathways after DHCA with ASCP were mainly involved in the activated glycolytic pathway, subdued anaerobic metabolism, and oxidative stress. In addition, L-kynurenine (P = 0.0019), 5-methoxyindole-3-acetic acid (P = 0.0499), and 5-hydroxyindole-3-acetic acid (P = 0.0495) in tryptophan metabolism pathways were decreased, and citrulline (P = 0.0158) in urea cycle was increased in group DA comparing to group D. CONCLUSIONS: The present study applied metabolomics analysis to identify the cerebral metabolic profiling in rabbits with ASCP, and the results may shed new lights that cerebral metabolism is better preserved by ASCP compared with DHCA alone. PMID: 26960374 [PubMed - as supplied by publisher]

Related Articles [Anti-dementia effect of Tongluo Xingnao effervescent tablet based on urinary metabonomics]. Zhongguo Zhong Yao Za Zhi. 2015 Aug;40(16):3287-92 Authors: Wei JP, Zhang YJ, Ma YT, Xu SJ, Wang YY Abstract Tongluo Xingnao effervescent tablet (TLXNET) is a patented prescription, which comes from modified Xionggui decoction and can improve cognitive function. However, its effect on the urine metabolites and anti-dementia mechanism in the dementia model rats induced by hippocampal injection with Aβ25-35 remains unclear. The experiment focused on the changes in trajectory and inter-relationship among the urinary metabolite of rats in the blank group, Aβ25-35 hippocampal injection dementia model group and the TLXNET intervention group, in order to determine theirs characteristic metabolic markers and explain the anti-dementia effect of TLX-NET base on the change of metabolic trajectory of these bio-markers. According to the experimental results, 5, 6-indolequinone, 4-hydroxyphenyl pyruvic acid (4-HPPA), cortisol and 3-thiosulfate lactic were preliminarily identified as the characteristic metabolic markers. They mainly participate in dopamine system, glucocorticoids and energy metabolic pathways. TLXNET can apparently downregulate the disturbances of metabolic trajectory of the four bio-markers. The experiment indicates that the dementia model induced by injecting Aβ25-3 into hippocampus has its characteristic endogenous metabolic markers in urine, and ELXNET can ameliorate dementia by down-regulating the disturbances of metabolic trajectory. PMID: 26790309 [PubMed - indexed for MEDLINE]

Related Articles Study of levan productivity from Bacillus subtilis Natto by surface response methodology and its antitumor activity against HepG2 cells using metabolomic approach. Pak J Pharm Sci. 2015 Nov;28(6):1917-26 Authors: Cabral de Melo FC, Borsato D, de Macedo Júnior FC, Mantovani MS, Luiz RC, Colabone-Celligoi MA Abstract Levan productivity of Bacillus subtilis Natto was evaluated in submerged culture varying the pH, temperature and culture time, using factorial design and response surface methodology. The characterization of levan molecular weight was performed by HPSEC and its antitumor activity against HepG2 cells using metabolomic approach was also evaluated. At first, the variables investigated, as well as their interactions, demonstrated significant effect. Further, a second design using the same variables at different levels was developed. Thus, according to the model, an optimized value corresponding to 5.82 g.L⁻¹.h⁻¹ was achieved at pH 8, 39.5°C in 21 hours, the highest value reported so far. After analysis by HPSEC, two molecular weights were obtained corresponding to 72.37 and 4146 kDa. The levan promoted an increase of acetate, alanine, lactate and phosphocreatine in HepG2 cells suggesting an alteration in the bioenergetics pathways and cellular homeostasis by intracellular accumulation of lactate, justifying its antitumor activity. PMID: 26639487 [PubMed - indexed for MEDLINE]

Related Articles LKB1 couples glucose metabolism to insulin secretion in mice. Diabetologia. 2015 Jul;58(7):1513-22 Authors: Fu A, Robitaille K, Faubert B, Reeks C, Dai XQ, Hardy AB, Sankar KS, Ogrel S, Al-Dirbashi OY, Rocheleau JV, Wheeler MB, MacDonald PE, Jones R, Screaton RA Abstract AIMS/HYPOTHESIS: Precise regulation of insulin secretion by the pancreatic beta cell is essential for the maintenance of glucose homeostasis. Insulin secretory activity is initiated by the stepwise breakdown of ambient glucose to increase cellular ATP via glycolysis and mitochondrial respiration. Knockout of Lkb1, the gene encoding liver kinase B1 (LKB1) from the beta cell in mice enhances insulin secretory activity by an undefined mechanism. Here, we sought to determine the molecular basis for how deletion of Lkb1 promotes insulin secretion. METHODS: To explore the role of LKB1 on individual steps in the insulin secretion pathway, we used mitochondrial functional analyses, electrophysiology and metabolic tracing coupled with by gas chromatography and mass spectrometry. RESULTS: Beta cells lacking LKB1 surprisingly display impaired mitochondrial metabolism and lower ATP levels following glucose stimulation, yet compensate for this by upregulating both uptake and synthesis of glutamine, leading to increased production of citrate. Furthermore, under low glucose conditions, Lkb1(-/-) beta cells fail to inhibit acetyl-CoA carboxylase 1 (ACC1), the rate-limiting enzyme in lipid synthesis, and consequently accumulate NEFA and display increased membrane excitability. CONCLUSIONS/INTERPRETATION: Taken together, our data show that LKB1 plays a critical role in coupling glucose metabolism to insulin secretion, and factors in addition to ATP act as coupling intermediates between feeding cues and secretion. Our data suggest that beta cells lacking LKB1 could be used as a system to identify additional molecular events that connect metabolism to cellular excitation in the insulin secretion pathway. PMID: 25874445 [PubMed - indexed for MEDLINE]