PubMed
A hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) based metabolomics study on colour stability of ovine meat.
A hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) based metabolomics study on colour stability of ovine meat.
Meat Sci. 2016 Feb 20;117:163-172
Authors: Subbaraj AK, Kim YH, Fraser K, Farouk MM
Abstract
Meat colour is one of the cues available to the consumer to gauge overall meat quality and wholesomeness. Colour stability of meat is determined by several factors both inherent to the animal and post-slaughter conditions, including ageing, storage/packaging and display times. A hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) based metabolomics study was undertaken to identify and compare polar metabolites between ovine meat samples that were exposed to different durations of ageing, storage conditions, and display times. Primary metabolites comprising amino acids, sugars, nucleotides, nucleosides, organic acids and their breakdown products were mainly identified as discriminating factors. For the first time, boron complexes of sugar and malic acid were also tentatively identified. As expected, most compounds identified were related to myoglobin chemistry, and compounds with antioxidant properties were found in higher levels in colour stable samples. Supplementary studies identifying semi-polar, non-polar and volatile compounds will provide a holistic understanding of the chemical basis of colour stability in ovine meat.
PMID: 26986230 [PubMed - as supplied by publisher]
Uptake of caprolactam and its influence on growth and oxygen production of Desmodesmus quadricauda algae.
Uptake of caprolactam and its influence on growth and oxygen production of Desmodesmus quadricauda algae.
Environ Pollut. 2016 Mar 14;213:518-523
Authors: Kalinová JP, Tříska J, Vrchotová N, Novák J
Abstract
The consumption of polyamides produced from caprolactam is increasing continuously, and for that reason the danger of environmental contamination by this lactam is also rising. This study's aim was to evaluate the influence of caprolactam on the growth and oxygen production of the green alga Desmodesmus quadricauda and on caprolactam uptake by this alga. The presence of caprolactam in water was observed to cause the algae significantly to increase its oxygen production. Caprolactam concentration of 5,000 mg/L stopped algae growth after 6 days and influenced coenobia structure (seen as disappearance of pyrenoids, deformation of cells) but did not decrease the number of cells in the coenobia. Caprolactam uptake is probably passive but relatively rapid. Maximum concentration in the algae was reached after 18-24 h.
PMID: 26985739 [PubMed - as supplied by publisher]
Association of Plasma Small-Molecule Intermediate Metabolites With Age and Body Mass Index Across Six Diverse Study Populations.
Association of Plasma Small-Molecule Intermediate Metabolites With Age and Body Mass Index Across Six Diverse Study Populations.
J Gerontol A Biol Sci Med Sci. 2016 Mar 16;
Authors: Kraus WE, Pieper CF, Huffman KM, Thompson DK, Kraus VB, Morey MC, Cohen HJ, Ravussin E, Redman LM, Bain JR, Stevens RD, Newgard CB
Abstract
BACKGROUND: Older age and obesity are associated with metabolic dysregulation; the mechanism by which these factors impact metabolism across the lifespan is important, but relatively unknown. We evaluated a panel of amino acids (AAs) and acylcarnitines (ACs) to identify effects of age and adiposity (body mass index) on circulating small-molecule metabolites in a meta-analysis of six diverse study populations.
METHODS: Targeted metabolic profiling was performed in six independent studies, representing 739 subjects with a broad range of age, body mass index, health states, and ethnic origin. Principal components analysis was performed on log-normalized values for AAs and ACs separately, generating one AC factor and two AA factors for each study. A common AC factor consisted primarily of acetylcarnitine, medium-chain AC, and several long-chain AC. AA Factor 1 consisted primarily of large neutral AAs. Glycine was its own factor.
RESULTS: Metabolic profiling and factor analysis identified clusters of related metabolites of lipid and AA metabolism that were consistently associated with age and body mass in a series of studies with a broad range of age, body mass index, and health status. An inverse association of glycine with body mass index and male gender supports its role as a marker of favorable metabolic health.
CONCLUSIONS: An important focus of future investigations should be to determine whether these clusters of metabolic intermediates are possible early predictors of health outcomes associated with body mass; are involved with accelerated aging; are involved in the causative pathway of aging; and how modification of these metabolic pathways impact the biology of aging.
PMID: 26984390 [PubMed - as supplied by publisher]
NMR- and GC/MS-based metabolomics of sulfur mustard exposed individuals: a pilot study.
NMR- and GC/MS-based metabolomics of sulfur mustard exposed individuals: a pilot study.
Biomarkers. 2016 Mar 17;:1-11
Authors: Nobakht BF, Aliannejad R, Rezaei-Tavirani M, Arefi Oskouie A, Naseri MT, Parastar H, Aliakbarzadeh G, Fathi F, Taheri S
Abstract
Sulfur mustard (SM) is a potent alkylating agent and its effects on cells and tissues are varied and complex. Due to limitations in the diagnostics of sulfur mustard exposed individuals (SMEIs) by noninvasive approaches, there is a great necessity to develop novel techniques and biomarkers for this condition. We present here the first nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC/MS) metabolic profiling of serum from and healthy controls to identify novel biomarkers in blood serum for better diagnostics. Of note, SMEIs were exposed to SM 30 years ago and that differences between two groups could still be found. Pathways in which differences between SMEIs and healthy controls are observed are related to lipid metabolism, ketogenesis, tricarboxylic acid (TCA) cycle and amino acid metabolism.
PMID: 26984270 [PubMed - as supplied by publisher]
SIMAT: GC-SIM-MS data analysis tool.
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SIMAT: GC-SIM-MS data analysis tool.
BMC Bioinformatics. 2015;16:259
Authors: Ranjbar MR, Di Poto C, Wang Y, Ressom HW
Abstract
BACKGROUND: Gas chromatography coupled with mass spectrometry (GC-MS) is one of the technologies widely used for qualitative and quantitative analysis of small molecules. In particular, GC coupled to single quadrupole MS can be utilized for targeted analysis by selected ion monitoring (SIM). However, to our knowledge, there are no software tools specifically designed for analysis of GC-SIM-MS data. In this paper, we introduce a new R/Bioconductor package called SIMAT for quantitative analysis of the levels of targeted analytes. SIMAT provides guidance in choosing fragments for a list of targets. This is accomplished through an optimization algorithm that has the capability to select the most appropriate fragments from overlapping chromatographic peaks based on a pre-specified library of background analytes. The tool also allows visualization of the total ion chromatograms (TIC) of runs and extracted ion chromatograms (EIC) of analytes of interest. Moreover, retention index (RI) calibration can be performed and raw GC-SIM-MS data can be imported in netCDF or NIST mass spectral library (MSL) formats.
RESULTS: We evaluated the performance of SIMAT using two GC-SIM-MS datasets obtained by targeted analysis of: (1) plasma samples from 86 patients in a targeted metabolomic experiment; and (2) mixtures of internal standards spiked in plasma samples at varying concentrations in a method development study. Our results demonstrate that SIMAT offers alternative solutions to AMDIS and MetaboliteDetector to achieve accurate detection of targets and estimation of their relative intensities by analysis of GC-SIM-MS data.
CONCLUSIONS: We introduce a new R package called SIMAT that allows the selection of the optimal set of fragments and retention time windows for target analytes in GC-SIM-MS based analysis. Also, various functions and algorithms are implemented in the tool to: (1) read and import raw data and spectral libraries; (2) perform GC-SIM-MS data preprocessing; and (3) plot and visualize EICs and TICs.
PMID: 26283310 [PubMed - indexed for MEDLINE]
Severe disturbance of glucose metabolism in peripheral blood mononuclear cells of schizophrenia patients: a targeted metabolomic study.
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Severe disturbance of glucose metabolism in peripheral blood mononuclear cells of schizophrenia patients: a targeted metabolomic study.
J Transl Med. 2015;13:226
Authors: Liu ML, Zhang XT, Du XY, Fang Z, Liu Z, Xu Y, Zheng P, Xu XJ, Cheng PF, Huang T, Bai SJ, Zhao LB, Qi ZG, Shao WH, Xie P
Abstract
BACKGROUND: Schizophrenia is a widespread and debilitating mental disorder. However, the underlying molecular mechanism of schizophrenia remains largely unknown and no objective laboratory tests are available to diagnose this disorder. The aim of the present study was to characterize the alternations of glucose metabolites and identify potential diagnostic biomarkers for schizophrenia.
METHODS: Gas chromatography/mass spectrometry based targeted metabolomic method was used to quantify the levels of 13 glucose metabolites in peripheral blood mononuclear cells (PBMCs) derived from healthy controls, schizophrenia and major depression subjects (n = 55 for each group).
RESULTS: The majority (84.6%) of glucose metabolites were significantly disturbed in schizophrenia subjects, while only two (15.4%) glucose metabolites were differently expressed in depression subjects relative to healthy controls in both training set (n = 35/group) and test set (n = 20/group). Antipsychotics had only a subtle effect on glucose metabolism pathway. Moreover, ribose 5-phosphate in PBMCs showed a high diagnostic performance for first-episode drug-naïve schizophrenia subjects.
CONCLUSION: These findings suggested disturbance of glucose metabolism may be implicated in onset of schizophrenia and could aid in development of diagnostic tool for this disorder.
PMID: 26169624 [PubMed - indexed for MEDLINE]
The effects of size and surface modification of amorphous silica particles on biodistribution and liver metabolism in mice.
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The effects of size and surface modification of amorphous silica particles on biodistribution and liver metabolism in mice.
Nanotechnology. 2015 May 1;26(17):175101
Authors: Lu X, Ji C, Jin T, Fan X
Abstract
Engineered nanoparticles, with unconventional properties, are promising platforms for biomedical applications. Since they may interact with a wide variety of biomolecules, it is critical to understand the impact of the physicochemical properties of engineered nanoparticles on biological systems. In this study, the effects of particle size and surface modification alone or in combination of amorphous silica particles (SPs) on biological responses were determined using a suite of general toxicological assessments and metabonomics analysis in mice model. Our results suggested that amino or carboxyl surface modification mitigated the liver toxicity of plain-surface SPs. 30 nm SPs with amino surface modification were found to be the most toxic SPs among all the surface-modified SP treatments at the same dosage. When treatment dose was increased, submicro-sized SPs with amino or carboxyl surface modification also induced liver toxicity. Biodistribution studies suggested that 70 nm SPs were mainly accumulated in liver and spleen regardless of surface modifications. Interestingly, these two organs exhibited different uptake trends. Furthermore, metabonomics studies indicated that surface modification plays a more dominant role to affect the liver metabolism than particle size.
PMID: 25837432 [PubMed - indexed for MEDLINE]
Diagnosis and Monitoring of Cystinosis Using Immunomagnetically Purified Granulocytes.
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Diagnosis and Monitoring of Cystinosis Using Immunomagnetically Purified Granulocytes.
Clin Chem. 2016 Mar 15;
Authors: Gertsman I, Johnson WS, Nishikawa C, Gangoiti JA, Holmes B, Barshop BA
Abstract
BACKGROUND: Cystine determination is a critical biochemical test for the diagnosis and therapeutic monitoring of the lysosomal storage disease cystinosis. The classical mixed-leukocyte cystine assay requires prompt specialized recovery/isolation following blood drawing, providing cystine concentrations normalized to total protein from assorted types of white blood cells, each with varying cystine content.
METHODS: We present a new workflow for cystine determination using immunomagnetic granulocyte purification, and new reference ranges established form 47 patient and 27 obligate heterozygote samples assayed. Samples were collected in acid-citrate dextrose tubes and their stability was proven to allow for overnight shipping before analysis. Cystine was quantified by LC-MS/MS.
RESULTS: The new method was reproducible (<15% root mean square error) and specific, assaying purified granulocytes from blood samples that no longer required immediate preparation and therefore allowing for up to 30 h before processing. There was a nearly a 2-fold increase in the therapeutic target (1.9 nmol half-cystine/mg protein) range, established using distributions of patient, obligate heterozygote, and control samples. The 2.5-97.5 percentile ranges (- 2 SD to + 2 SD around mean) for these cohorts were 0.67- 6.05 nmol/mg protein for patients, 0.33-1.35 nmol/mg protein for obligate heterozygotes, and 0.09-0.35 nmol/mg protein for controls.
CONCLUSIONS: The intracellular cystine determination method using immunopurified granulocytes followed by LC-MS/MS analysis improves the inherent variability of mixed leukocyte analysis and eliminates the need for immediate sample preparation following blood draw.
PMID: 26980209 [PubMed - as supplied by publisher]
The Presence Of Lc3b Puncta And Hmgb1 Expression In Malignant Cells Correlate With The Immune Infiltrate In Breast Cancer.
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The Presence Of Lc3b Puncta And Hmgb1 Expression In Malignant Cells Correlate With The Immune Infiltrate In Breast Cancer.
Autophagy. 2016 Mar 16;:0
Authors: Ladoire S, Enot D, Senovilla L, Ghiringhelli F, Poirier-Colame V, Chaba K, Semeraro M, Chaix M, Penault-Llorca F, Arnould L, Poillot ML, Arveux P, Delaloge S, Andre F, Zitvogel L, Kroemer G
Abstract
Several cell-intrinsic alterations have poor prognostic features in human breast cancer, as exemplified by the absence of MAP1LC3B/LC3B (microtubule associated protein 1 light chain 3 beta)-positive puncta in the cytoplasm (which indicates reduced autophagic flux) or the loss of nuclear HMGB1 expression by malignant cells. It is well established that breast cancer is under strong immunosurveillance, as reflected by the fact that scarce infiltration of the malignant lesion by CD8(+) cytotoxic T lymphocytes or comparatively dense infiltration by immunosuppressive cell types (such as FOXP3(+) regulatory T cells or CD68(+) tumor-associated macrophages), resulting in low CD8(+):FOXP3(+) or CD8(+):CD68(+) ratios, has a negative prognostic impact. Here, we reveal the surprising finding that cell-intrinsic features may influence the composition of the immune infiltrate in human breast cancer. Thus, the absence of LC3B puncta is correlated with intratumoral (but not peritumoral) infiltration by fewer CD8(+) cells and more FOXP3(+) or CD68(+) cells, resulting in a major drop in the CD8(+):FOXP3(+) or CD8(+):CD68(+) ratios. Moreover, absence of HMGB1 expression in nucleus correlated with a general drop in all immune effectors, in particular FOXP3(+) and CD68(+) cells, both within the tumor and close to it. Combined analysis of LC3B puncta and HMGB1 expression allowed for improved stratification of patients with respect to the characteristics of their immune infiltrate as well as overall and metastasis-free survival. It can be speculated that blocked autophagy in, or HMGB1 loss from, cancer cells may favor tumor progression due to their negative impact on anticancer immunosurveillance.
PMID: 26979828 [PubMed - as supplied by publisher]
Insights into mutualism mechanism and versatile metabolism of Ketogulonicigenium vulgare Hbe602 based on comparative genomics and metabolomics studies.
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Insights into mutualism mechanism and versatile metabolism of Ketogulonicigenium vulgare Hbe602 based on comparative genomics and metabolomics studies.
Sci Rep. 2016;6:23068
Authors: Jia N, Ding MZ, Du J, Pan CH, Tian G, Lang JD, Fang JH, Gao F, Yuan YJ
Abstract
Ketogulonicigenium vulgare has been widely used in vitamin C two steps fermentation and requires companion strain for optimal growth. However, the understanding of K. vulgare as well as its companion strain is still preliminary. Here, the complete genome of K. vulgare Hbe602 was deciphered to provide insight into the symbiosis mechanism and the versatile metabolism. K. vulgare contains the LuxR family proteins, chemokine proteins, flagellar structure proteins, peptides and transporters for symbiosis consortium. Besides, the growth state and metabolite variation of K. vulgare were observed when five carbohydrates (D-sorbitol, L-sorbose, D-glucose, D-fructose and D-mannitol) were used as carbon source. The growth increased by 40.72% and 62.97% respectively when K. vulgare was cultured on D-mannitol/D-sorbitol than on L-sorbose. The insufficient metabolism of carbohydrates, amino acids and vitamins is the main reason for the slow growth of K. vulgare. The combined analysis of genomics and metabolomics indicated that TCA cycle, amino acid and nucleotide metabolism were significantly up-regulated when K. vulgare was cultured on the D-mannitol/D-sorbitol, which facilitated the better growth. The present study would be helpful to further understand its metabolic structure and guide the engineering transformation.
PMID: 26979567 [PubMed - in process]
Metabolomics: beyond biomarkers and towards mechanisms.
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Metabolomics: beyond biomarkers and towards mechanisms.
Nat Rev Mol Cell Biol. 2016 Mar 16;
Authors: Johnson CH, Ivanisevic J, Siuzdak G
Abstract
Metabolomics, which is the profiling of metabolites in biofluids, cells and tissues, is routinely applied as a tool for biomarker discovery. Owing to innovative developments in informatics and analytical technologies, and the integration of orthogonal biological approaches, it is now possible to expand metabolomic analyses to understand the systems-level effects of metabolites. Moreover, because of the inherent sensitivity of metabolomics, subtle alterations in biological pathways can be detected to provide insight into the mechanisms that underlie various physiological conditions and aberrant processes, including diseases.
PMID: 26979502 [PubMed - as supplied by publisher]
In vitro steroid profiling system for the evaluation of endocrine disruptors.
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In vitro steroid profiling system for the evaluation of endocrine disruptors.
J Biosci Bioeng. 2016 Mar 12;
Authors: Nakano Y, Yamashita T, Okuno M, Fukusaki E, Bamba T
Abstract
Endocrine disruptors (ED) are chemicals that affect various aspects of the endocrine system, often leading to the inhibition of steroidogenesis. Current chemical safety policies that restrict human exposure to such chemicals describe often time-consuming and costly methods for the evaluation of ED effects. We aimed to develop an effective tool for accurate phenotypic chemical toxicology studies. We developed an in vitro ED evaluation system using gas chromatography/mass spectrometry (GC/MS/MS) methods for metabolomic analysis of multi-marker profiles. Accounting for sample preparation and GC/MS/MS conditions, we established a screening method that allowed the simultaneous analysis of 17 steroids with good reproducibility and a linear calibration curve. Moreover, we applied the developed system to H295R human adrenocortical cells exposed to forskolin and prochloraz in accordance with the Organization for Economic Cooperation and Development (OECD) guidelines and observed dose-dependent variations in steroid profiles. While the OECD guidelines include only testosterone and 17β-estradiol, our system enabled a comprehensive and highly sensitive analysis of steroid profile alteration due to ED exposure. The application of our ED evaluation screen could be economical and provide novel insights into the hazards of ED exposure to the endocrine system.
PMID: 26979344 [PubMed - as supplied by publisher]
(1)H NMR brain metabonomics of scrapie exposed sheep.
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(1)H NMR brain metabonomics of scrapie exposed sheep.
Mol Biosyst. 2015 Jul;11(7):2008-16
Authors: Scano P, Rosa A, Incani A, Maestrale C, Santucciu C, Perra D, Vascellari S, Pani A, Ligios C
Abstract
While neurochemical metabolite modifications, determined by different techniques, have been diffusely reported in human and mice brains affected by transmissible spongiform encephalopathies (TSEs), this aspect has been little studied in the natural animal hosts with the same pathological conditions so far. Herein, we investigated, by high resolution (1)H NMR spectroscopy and multivariate statistical data analysis, the brain metabolite profile of sheep exposed to a scrapie agent in a naturally affected flock. On the basis of clinical examinations and western blotting analysis for the pathological prion protein (PrP(Sc)) in brain tissues, sheep were catalogued as not infected (H), infected with clinical signs (S), and infected without clinical signs (A). By discriminant analysis of spectral data, comparing S vs. H, we found a different metabolite distribution, with inosine, cytosine, creatine, and lactate being higher in S than in H brains, while the branched chain amino acids (leucine, isoleucine, and valine), phenylalanine, uracil, tyrosine, gamma-amino butyric acid, total aspartate (aspartate + N-acetyl aspartate) being lower in S. By a soft independent modelling of class analogy approach, 1 out of 3 A samples was assigned to class H. Furthermore, A brains were found to be higher in choline and choline-containing compounds. By means of partial least squares regression, an excellent correlation was found between the PrP(Sc) amount and the (1)H NMR metabolite profile of infected (S and A) sheep, and the metabolite mostly correlated with PrP(Sc) was alanine. The overall results, obtained using different chemometric tools, were able to describe a brain metabolite profile of infected sheep with and without clinical signs, compared to healthy ones, and indicated alanine as a biomarker for PrP(Sc) amounts in scrapie brains.
PMID: 25959287 [PubMed - indexed for MEDLINE]
A metabolomic study of adipose tissue in mice with a disruption of the circadian system.
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A metabolomic study of adipose tissue in mice with a disruption of the circadian system.
Mol Biosyst. 2015 Jul;11(7):1897-906
Authors: Castro C, Briggs W, Paschos GK, FitzGerald GA, Griffin JL
Abstract
Adipose tissue functions in terms of energy homeostasis as a rheostat for blood triglyceride, regulating its concentration, in response to external stimuli. In addition it acts as a barometer to inform the central nervous system of energy levels which can vary dramatically between meals and according to energy demand. Here a metabolomic approach, combining both Mass Spectrometry and Nuclear Magnetic Resonance spectroscopy, was used to analyse both white and brown adipose tissue in mice with adipocyte-specific deletion of Arntl (also known as Bmal1), a gene encoding a core molecular clock component. The results are consistent with a peripheral circadian clock playing a central role in metabolic regulation of both brown and white adipose tissue in rodents and show that Arntl induced global changes in both tissues which were distinct for the two types. In particular, anterior subcutaneous white adipose tissue (ASWAT) tissue was effected by a reduction in the degree of unsaturation of fatty acids, while brown adipose tissue (BAT) changes were associated with a reduction in chain length. In addition the aqueous fraction of metabolites in BAT were profoundly affected by Arntl disruption, consistent with the dynamic role of this tissue in maintaining body temperature across the day-night cycle and an upregulation in fatty acid oxidation and citric acid cycle activity to generate heat during the day when rats are inactive (increases in 3-hydroxybutyrate and glutamate), and increased synthesis and storage of lipids during the night when rats feed more (increased concentrations of glycerol, choline and glycerophosphocholine).
PMID: 25907923 [PubMed - indexed for MEDLINE]
Effects of thyroid hormone status on metabolic pathways of arachidonic acid in mice and humans: A targeted metabolomic approach.
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Effects of thyroid hormone status on metabolic pathways of arachidonic acid in mice and humans: A targeted metabolomic approach.
Prostaglandins Other Lipid Mediat. 2015 Apr-Jun;118-119:11-8
Authors: Yao X, Sa R, Ye C, Zhang D, Zhang S, Xia H, Wang YC, Jiang J, Yin H, Ying H
Abstract
Symptoms of cardiovascular diseases are frequently found in patients with hypothyroidism and hyperthyroidism. However, it is unknown whether arachidonic acid metabolites, the potent mediators in cardiovascular system, are involved in cardiovascular disorders caused by hyperthyroidism and hypothyroidism. To answer this question, serum levels of arachidonic acid metabolites in human subjects with hypothyroidism, hyperthyroidism and mice with hypothyroidism or thyroid hormone treatment were determined by a mass spectrometry-based method. Over ten arachidonic acid metabolites belonging to three catalytic pathways: cyclooxygenases, lipoxygenases, and cytochrome P450, were quantified simultaneously and displayed characteristic profiles under different thyroid hormone status. The level of 20-hydroxyeicosatetraenoic acid, a cytochrome P450 metabolite, was positively correlated with thyroid hormone level and possibly contributed to the elevated blood pressured in hyperthyroidism. The increased prostanoid (PG) I2 and decreased PGE2 levels in hypothyroid patients might serve to alleviate atherosclerosis associated with dyslipidemia. The elevated level of thromboxane (TX) A2, as indicated by TXB2, in hyperthyroid patients and mice treated with thyroid hormone might bring about pulmonary hypertension frequently found in hyperthyroid patients. In conclusion, our prospective study revealed that arachidonic acid metabolites were differentially affected by thyroid hormone status. Certain metabolites may be involved in cardiovascular disorders associated with thyroid diseases.
PMID: 25841349 [PubMed - indexed for MEDLINE]
Hypoxia-induced metabolic stress in retinal pigment epithelial cells is sufficient to induce photoreceptor degeneration.
Hypoxia-induced metabolic stress in retinal pigment epithelial cells is sufficient to induce photoreceptor degeneration.
Elife. 2016 Mar 15;5
Authors: Kurihara T, Westenskow PD, Gantner ML, Usui Y, Schultz A, Bravo S, Aguilar E, Wittgrove C, Friedlander MS, Paris LP, Chew E, Siuzdak G, Friedlander M
Abstract
Photoreceptors are the most numerous and metabolically demanding cells in the retina. Their primary nutrient source is the choriocapillaris, and both the choriocapillaris and photoreceptors require trophic and functional support from retinal pigment epithelium (RPE) cells. Defects in RPE, photoreceptors, and the choriocapillaris are characteristic of age-related macular degeneration (AMD), a common vision-threatening disease. RPE dysfunction or death is a primary event in AMD, but the combination(s) of cellular stresses that affect the function and survival of RPE are incompletely understood. Here, using mouse models in which hypoxia can be genetically triggered in RPE, we show that hypoxia-induced metabolic stress alone leads to photoreceptor atrophy. Glucose and lipid metabolism are radically altered in hypoxic RPE cells; these changes impact nutrient availability for the sensory retina and promote progressive photoreceptor degeneration. Understanding the molecular pathways that control these responses may provide important clues about AMD pathogenesis and inform future therapies.
PMID: 26978795 [PubMed - as supplied by publisher]
Overdose taking curcumin initiating the unbalanced state of bodies.
Overdose taking curcumin initiating the unbalanced state of bodies.
J Agric Food Chem. 2016 Mar 15;
Authors: Qiu P, Man S, Li J, Liu J, Zhang L, Yu P, Gao W
Abstract
Curcumin is the major active component of turmeric and widely used as spice and coloring agent in food. However, its safety evaluation has been few investigated. To evaluate the 90-day subchronic toxicity of curcumin in rats, its general observation, clinical biochemistry, pathology and metabolomics were evaluated. The results showed that curcumin induced liver injury through the generation of the over-expression of reactive oxygen species (ROS) and pro-inflammatory cytokines IL6, and the decrease of the levels of antioxidant enzyme SOD and detoxified enzyme GST. Meanwhile, as the self-protection of rats, curcumin treatment activated the transcription of Nrf2 and elevated the expression of HO-1 to reduce tissues damage. What's more, curcumin significantly increased key mRNA levels of HK2, PKM2, LDHA, CES, Cpt1, Cpt2, FASN, and ATP5b, and decreased levels of GLUT2 and ACC1 to enhance glycolysis and inhibit lipid metabolism and TCA cycle. Therefore, overdose or long-term taking curcumin could initiate the unbalanced state of bodies through oxidative stress, inflammation and metabolic disorders, which induces liver injury. It's necessary for intermittent administration of curcumin in our daily life.
PMID: 26978516 [PubMed - as supplied by publisher]
Impact of 4-epi-oxytetracycline on the gut microbiota and blood metabolomics of Wistar rats.
Impact of 4-epi-oxytetracycline on the gut microbiota and blood metabolomics of Wistar rats.
Sci Rep. 2016;6:23141
Authors: Han H, Xiao H, Zhang K, Lu Z
Abstract
The impact of 4-epi-oxytetracycline (4-EOTC), one of the main oxytetracycline (OTC) metabolites, on the gut microbiota and physiological metabolism of Wistar rats was analyzed to explore the dynamic alterations apparent after repeated oral exposure (0.5, 5.0 or 50.0 mg/kg bw) for 15 days as shown by 16S rRNA pyrosequencing and UPLC-Q-TOF/MS analysis. Both principal component analysis and cluster analysis showed consistently altered patterns with distinct differences in the treated groups versus the control groups. 4-EOTC treatment at 5.0 or 50.0 mg/kg increased the relative abundance of the Actinobacteria, specifically Bifidobacteriaceae, and improved the synthesis of lysophosphatidylcholine (LysoPC), as shown by the lipid biomarkers LysoPC(16:0), LysoPC(18:3), LysoPC(20:3), and LysoPC(20:4). The metabolomic analysis of urine samples also identified four other decreased metabolites: diacylglycerol, sphingomyelin, triacylglycerol, and phosphatidylglycerol. Notably, the significant changes observed in these biomarkers demonstrated the ongoing disorder induced by 4-EOTC. Blood and urine analysis revealed that residual 4-EOTC accumulated in the rats, even two weeks after oral 4-EOTC administration, ceased. Thus, through thorough analysis, it can be concluded that the alteration of the gut microbiota and disorders in blood metabolomics are correlated with 4-EOTC treatment.
PMID: 26976662 [PubMed - in process]
Manipulating proteostasis to repair the F508del-CFTR defect in cystic fibrosis.
Manipulating proteostasis to repair the F508del-CFTR defect in cystic fibrosis.
Mol Cell Pediatr. 2016 Dec;3(1):13
Authors: Esposito S, Tosco A, Villella VR, Raia V, Kroemer G, Maiuri L
Abstract
Cystic fibrosis (CF) is a lethal monogenic disease caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that entails the (diagnostic) increase in sweat electrolyte concentrations, progressive lung disease with chronic inflammation and recurrent bacterial infections, pancreatic insufficiency, and male infertility. Therapies aimed at restoring the CFTR defect have emerged. Thus, a small molecule which facilitates chloride channel opening, the potentiator Ivacaftor, has been approved for the treatment of CF patients bearing a particular class of rare CFTR mutations. However, small molecules that directly target the most common misfolded CFTR mutant, F508del, and improve its intracellular trafficking in vitro, have been less effective than expected when tested in CF patients, even in combination with Ivacaftor. Thus, new strategies are required to circumvent the F508del-CFTR defect. Airway and intestinal epithelial cells from CF patients bearing the F508del-CFTR mutation exhibit an impressive derangement of cellular proteostasis, with oxidative stress, overactivation of the tissue transglutaminase (TG2), and disabled autophagy. Proteostasis regulators such as cysteamine can rescue and stabilize a functional F508del-CFTR protein through suppressing TG2 activation and restoring autophagy in vivo in F508del-CFTR homozygous mice, in vitro in CF patient-derived cell lines, ex vivo in freshly collected primary patient's nasal cells, as well as in a pilot clinical trial involving homozygous F508del-CFTR patients. Here, we discuss how the therapeutic normalization of defective proteostasis can be harnessed for the treatment of CF patients with the F508del-CFTR mutation.
PMID: 26976279 [PubMed]
Metabolites Associated With Circulating Interleukin-6 in Older Adults.
Metabolites Associated With Circulating Interleukin-6 in Older Adults.
J Gerontol A Biol Sci Med Sci. 2016 Mar 14;
Authors: Lustgarten MS, Fielding RA
Abstract
BACKGROUND: Circulating levels of the pro-inflammatory cytokine interleukin-6 (IL-6) levels are elevated in older adults, but mechanisms are unclear. In the current study, we used an untargeted metabolomic approach to develop an improved understanding about mechanisms related to circulating IL-6 in older adults.
METHODS: Serum IL-6 values were log-transformed to normalize its distribution. Multivariable-adjusted linear regression was used to examine the association between 324 serum metabolites with log IL-6. Backward elimination linear regression was used to develop a metabolite predictor set representative of log IL-6.
RESULTS: Thirty-six metabolites were significantly associated (p < 0.05 and q < 0.30) with log IL-6 in 73 older adults (average age, 78 years). Metabolites related to tryptophan metabolism (kynurenine, 3-indoxyl sulfate, indoleacetate, indolepropionate, C-glycosyltryptophan), infectious burden (C-glycosyltryptophan, N6-carbamoylthreonyladenosine, 1-methylurate, N-formylmethionine, N1-methyladenosine, 3-indoxyl sulfate, bilirubin (E,E), indoleacetate, γ-CEHC, N-acetylneuraminate), aryl hydrocarbon receptor activation and cytochrome P450 (CYP) 1A expression (kynurenine, 3-indoxyl sulfate, indoleacetate, N6-carbamoylthreonyladenosine, bilirubin, 1-methylurate) were positively associated, whereas metabolites related to CYP-mediated ω-oxidation (adipate, 8-hydroxyoctanoate, azelate, sebacate, undecanedioate, γ-CEHC), and peroxisome proliferator activated receptor-alpha (PPAR-α) activation (13 + 9-HODE, bilirubin, 5-oxoproline, cholesterol, glycerate, uridine) were negatively associated with log IL-6. The use of backward elimination regression identified tyrosine, cysteine, uridine, bilirubin, N-formylmethionine, indoleacetate, and 3-indoxyl sulfate to collectively explain 51% of the variance inherent in log IL-6.
CONCLUSIONS: These data suggest roles for tryptophan metabolism, infectious burden, activation of host defense, and detoxification through CYP1A-mediated pathways in mechanisms related to elevated inflammation, whereas CYP-mediated ω-oxidation and PPAR-α activation may be related to decreased inflammation in older adults.
PMID: 26975982 [PubMed - as supplied by publisher]