PubMed
1,25(OH)2D3 Disrupts glucose metabolism in prostate cancer cells leading to a truncation of the tca cycle and inhibition of txnip expression.
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1,25(OH)2D3 Disrupts glucose metabolism in prostate cancer cells leading to a truncation of the tca cycle and inhibition of txnip expression.
Biochim Biophys Acta. 2017 Jun 23;:
Authors: Abu El Maaty MA, Alborzinia H, Khan SJ, Büttner M, Wölfl S
Abstract
Prostate cell metabolism exhibits distinct profiles pre- and post-malignancy. The malignant metabolic shift converts prostate cells from "citrate-producing" to "citrate-oxidizing" cells, thereby enhancing glucose metabolism, a phenotype that contrasts classical tumoral Warburg metabolism. An on-line biosensor chip system (BIONAS 2500) was used to monitor metabolic changes (glycolysis and respiration) in response to the putative anti-cancer nutraceutical 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], in different prostate cancer (PCa) cell lines (LNCaP, VCaP, DU145 and PC3). LNCaP cells exhibited profound metabolic responsiveness to the treatment and thus extensive analysis of metabolism-modulating effects of 1,25(OH)2D3 were performed, including mRNA expression analysis of key metabolic genes (e.g. GLUT1 and PDHK1), analysis of TCA cycle metabolites, glucose uptake/consumption measurements, ATP production, and mitochondrial biogenesis/activity. All together, data demonstrate a vivid disruption of glucose metabolism by 1,25(OH)2D3, illustrated by a decreased glucose uptake and an accumulation of citrate/isocitrate due to TCA cycle truncation. Depletion of glycolytic intermediates led to a consistent decrease in TXNIP expression in response to 1,25(OH)2D3, an effect that coincided with the activation of AMPK signaling and a reduction in c-MYC expression. Reduction in TXNIP levels in response to 1,25(OH)2D3 was rescued by an AMPK signaling inhibitor and mimicked by a MYC inhibitor highlighting the possible involvement of both pathways in mediating 1,25(OH)2D3's metabolic effects in PCa cells. Furthermore, pharmacological and genetic modulation of the androgen receptor showed similar and disparate effects on metabolic parameters compared to 1,25(OH)2D3 treatment, highlighting the AR-independent nature of 1,25(OH)2D3's metabolism-modulating effects.
PMID: 28651973 [PubMed - as supplied by publisher]
A novel 5-fluorouracil-resistant human esophageal squamous cell carcinoma cell line Eca-109/5-FU with significant drug resistance-related characteristics.
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A novel 5-fluorouracil-resistant human esophageal squamous cell carcinoma cell line Eca-109/5-FU with significant drug resistance-related characteristics.
Oncol Rep. 2017 May;37(5):2942-2954
Authors: Zhang C, Ma Q, Shi Y, Li X, Wang M, Wang J, Ge J, Chen Z, Wang Z, Jiang H
Abstract
5-Fluorouracil (5-FU) is used for the clinical treatment of esophageal squamous cell carcinomas (ESCCs), yet it also induces chemoresistant cancer cells during treatment, which leads to the failure of the therapy. To further explore the resistance mechanism of 5-FU in ESCC, we established the 5-FU-resistant ESCC cell line Eca-109/5-FU, which was prepared by the stepwise exposure to increasing 5-FU concentrations. MTT assay and nude mouse xenograft models were used to test the drug resistance and proliferation of Eca-109 and Eca-109/5-FU cells in vitro and in vivo. Apoptosis and cell cycle distribution were determined using flow cytometry. Drug resistance-related proteins were detected by western blotting. Metabolomic profiles were obtained from nuclear magnetic resonance (NMR) tests. In regards to Eca-109/5-FU, the decreased susceptibility to 5-FU was determined in vitro and in vivo with slower rate of proliferation. Drug resistance-related proteins (multidrug resistance-associated protein 1 and ATP-binding cassette superfamily G member 2), epithelial-to-mesenchymal transition (EMT)-related proteins (E-cadherin and vimentin) and cancer stem cell-related proteins (prominin-1 and hyaluronate receptor) exhibited significant differences between the two cell lines. The 5-FU-resistant cell line Eca-109/5-FU achieved the ability to tolerate 5-FU, which may depend on significant drug resistance-related characteristics, such as EMT and cancer stem cell-like properties. The metabolism of Eca-109/5-FU was altered, and more than 15 metabolites was found to contribute to the difference in the metabolite profile, such as lactate, glutamate, taurine, glutamine, proline, aspartate, methanol, cystine, glycine and uracil. Our results identified that the resistant cell line Eca-109/5-FU showed quite different characteristics compared with the parental Eca-109 cells. The Eca-109/5-FU cell line provides an experimental model for further steps to select chemotherapeutic sensitizers.
PMID: 28393186 [PubMed - indexed for MEDLINE]
Chemoproteomic Profiling of Acetanilide Herbicides Reveals Their Role in Inhibiting Fatty Acid Oxidation.
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Chemoproteomic Profiling of Acetanilide Herbicides Reveals Their Role in Inhibiting Fatty Acid Oxidation.
ACS Chem Biol. 2017 Mar 17;12(3):635-642
Authors: Counihan JL, Duckering M, Dalvie E, Ku WM, Bateman LA, Fisher KJ, Nomura DK
Abstract
Acetanilide herbicides are among the most widely used pesticides in the United States, but their toxicological potential and mechanisms remain poorly understood. Here, we have used chemoproteomic platforms to map proteome-wide cysteine reactivity of acetochlor (AC), the most widely used acetanilide herbicide, in vivo in mice. We show that AC directly reacts with >20 protein targets in vivo in mouse liver, including the catalytic cysteines of several thiolase enzymes involved in mitochondrial and peroxisomal fatty acid oxidation. We show that the fatty acids that are not oxidized, due to impaired fatty acid oxidation, are instead diverted into other lipid pathways, resulting in heightened free fatty acids, triglycerides, cholesteryl esters, and other lipid species in the liver. Our findings show the utility of chemoproteomic approaches for identifying novel mechanisms of toxicity associated with environmental chemicals like acetanilide herbicides.
PMID: 28094496 [PubMed - indexed for MEDLINE]
An Engineered Allele of afsQ1 Facilitates the Discovery and Investigation of Cryptic Natural Products.
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An Engineered Allele of afsQ1 Facilitates the Discovery and Investigation of Cryptic Natural Products.
ACS Chem Biol. 2017 Mar 17;12(3):628-634
Authors: Daniel-Ivad M, Hameed N, Tan S, Dhanjal R, Socko D, Pak P, Gverzdys T, Elliot MA, Nodwell JR
Abstract
New approaches to antimicrobial discovery are needed to address the growing threat of antibiotic resistance. The Streptomyces genus, a proven source of antibiotics, is recognized as having a large reservoir of untapped secondary metabolic genes, many of which are likely to produce uncharacterized compounds. However, most of these compounds are currently inaccessible, as they are not expressed under standard laboratory conditions. Here, we present a novel methodology for activating these "cryptic" metabolites by heterologously expressing a constitutively active pleiotropic regulator. By screening wild Streptomyces isolates, we identified the antibiotic siamycin-I, a lasso peptide that we show is active against multidrug pathogens. We further revealed that siamycin-I interferes with cell wall integrity via lipid II. This new technology has the potential to be broadly applied for use in the discovery of additional "cryptic" metabolites.
PMID: 28075554 [PubMed - indexed for MEDLINE]
Lipid Osteoclastokines Regulate Breast Cancer Bone Metastasis.
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Lipid Osteoclastokines Regulate Breast Cancer Bone Metastasis.
Endocrinology. 2017 Mar 01;158(3):477-489
Authors: Krzeszinski JY, Schwaid AG, Cheng WY, Jin Z, Gallegos ZR, Saghatelian A, Wan Y
Abstract
Bone metastasis is a deadly consequence of cancers, in which osteoclast forms a vicious cycle with tumor cells. Bone metastasis attenuation by clinical usage of osteoclast inhibitors and in our osteopetrotic mouse genetic models with β-catenin constitutive activation or peroxisome proliferator-activated receptor γ deficiency fully support the important role of osteoclast in driving the bone metastatic niche. However, the mechanisms for this "partnership in crime" are underexplored. Here we show that osteoclasts reprogram their lipid secretion to support cancer cells. Metabolomic profiling reveals elevated prometastatic arachidonic acid (AA) but reduced antimetastatic lysophosphatidylcholines (LPCs). This shift in lipid osteoclastokines synergistically stimulates tumor cell proliferation, migration, survival, and expression of prometastatic genes. Pharmacologically, combined treatment with LPCs and BW-755C, an inhibitor of AA signaling via blocking lipoxygenase and cyclooxygenase, impedes breast cancer bone metastasis. Our findings elucidate key paracrine mechanisms for the osteoclast-cancer vicious cycle and uncover important therapeutic targets for bone metastasis.
PMID: 27967239 [PubMed - indexed for MEDLINE]
The Effects of Long-Term Saturated Fat Enriched Diets on the Brain Lipidome.
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The Effects of Long-Term Saturated Fat Enriched Diets on the Brain Lipidome.
PLoS One. 2016;11(12):e0166964
Authors: Giles C, Takechi R, Mellett NA, Meikle PJ, Dhaliwal S, Mamo JC
Abstract
The brain is highly enriched in lipids, where they influence neurotransmission, synaptic plasticity and inflammation. Non-pathological modulation of the brain lipidome has not been previously reported and few studies have investigated the interplay between plasma lipid homeostasis relative to cerebral lipids. This study explored whether changes in plasma lipids induced by chronic consumption of a well-tolerated diet enriched in saturated fatty acids (SFA) was associated with parallel changes in cerebral lipid homeostasis. Male C57Bl/6 mice were fed regular chow or the SFA diet for six months. Plasma, hippocampus (HPF) and cerebral cortex (CTX) lipids were analysed by LC-ESI-MS/MS. A total of 348 lipid species were determined, comprising 25 lipid classes. The general abundance of HPF and CTX lipids was comparable in SFA fed mice versus controls, despite substantial differences in plasma lipid-class abundance. However, significant differences in 50 specific lipid species were identified as a consequence of SFA treatment, restricted to phosphatidylcholine (PC), phosphatidylethanolamine (PE), alkyl-PC, alkenyl-PC, alkyl-PE, alkenyl-PE, cholesterol ester (CE), diacylglycerol (DG), phosphatidylinositol (PI) and phosphatidylserine (PS) classes. Partial least squares regression of the HPF/CTX lipidome versus plasma lipidome revealed the plasma lipidome could account for a substantial proportion of variation. The findings demonstrate that cerebral abundance of specific lipid species is strongly associated with plasma lipid homeostasis.
PMID: 27907021 [PubMed - indexed for MEDLINE]
Consumption of Walnuts in Combination with Other Whole Foods Produces Physiologic, Metabolic, and Gene Expression Changes in Obese C57BL/6J High-Fat-Fed Male Mice.
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Consumption of Walnuts in Combination with Other Whole Foods Produces Physiologic, Metabolic, and Gene Expression Changes in Obese C57BL/6J High-Fat-Fed Male Mice.
J Nutr. 2016 Sep;146(9):1641-50
Authors: Luo T, Miranda-Garcia O, Adamson A, Hamilton-Reeves J, Sullivan DK, Kinchen JM, Shay NF
Abstract
BACKGROUND: Although a reductionist approach has sought to understand the roles of individual nutrients and biochemicals in foods, it has become apparent that there can be differences when studying food components in isolation or within the natural matrix of a whole food.
OBJECTIVE: The objective of this study was to determine the ability of whole-food intake to modulate the development of obesity and other metabolic dysfunction in mice fed a high-fat (HF), Western-style obesogenic diet. To test the hypothesis that an n-3 (ω-3) polyunsaturated fatty acid-rich food could synergize with other, largely polyphenol-rich foods by producing greater reductions in metabolic disease conditions, the intake of English walnuts was evaluated in combination with 9 other whole foods.
METHODS: Eight-week-old male C57Bl/6J mice were fed low-fat (LF; 10% fat) and HF control diets, along with an HF diet with 8.6% (wt:wt) added walnuts for 9 wk. The HF control diet contained 46% fat with added sucrose (10.9%, wt:wt) and cholesterol (1%, wt:wt); the added sucrose and cholesterol were not present in the LF diet. Other groups were provided the walnut diet with a second whole food-raspberries, apples, cranberries, tart cherries, broccoli sprouts, olive oil, soy protein, or green tea. All of the energy-containing whole foods were added at an energy level equivalent to 1.5 servings/d. Body weights, food intake, and glucose tolerance were determined. Postmortem, serum lipids and inflammatory markers, hepatic fat, gene expression, and the relative concentrations of 594 biochemicals were measured.
RESULTS: The addition of walnuts with either raspberries, apples, or green tea reduced glucose area under the curve compared with the HF diet alone (-93%, -64%, and -54%, respectively, P < 0.05). Compared with HF-fed mice, mice fed walnuts with either broccoli sprouts or green tea (-49% and -61%, respectively, P < 0.05) had reduced hepatic fat concentrations. There were differences in global gene expression patterns related to whole-food content, with many examples of differences in LF- and HF-fed mice, HF- and walnut-fed mice, and mice fed walnuts and walnuts plus other foods. The mean ± SEM increase in relative hepatic concentrations of the n-3 fatty acids α-linolenic acid, eicosapentanoic acid, and docosapentanoic acid in all walnut-fed groups was 124% ± 13%, 159% ± 11%, and 114% ± 10%, respectively (P < 0.0001), compared with LF- and HF-fed mice not consuming walnuts.
CONCLUSIONS: In obese male mice, walnut consumption with an HF Western-style diet caused changes in hepatic fat concentrations, gene expression patterns, and fatty acid concentrations. The addition of a second whole food in combination with walnuts produced other changes in metabolite concentrations and gene expression patterns and other physiologic markers. Importantly, these substantial changes occurred in mice fed typical amounts of intake, representing only 1.5 servings each food/d.
PMID: 27489005 [PubMed - indexed for MEDLINE]
Metabolomic profiling to dissect the role of visceral fat in cardiometabolic health.
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Metabolomic profiling to dissect the role of visceral fat in cardiometabolic health.
Obesity (Silver Spring). 2016 Jun;24(6):1380-8
Authors: Menni C, Migaud M, Glastonbury CA, Beaumont M, Nikolaou A, Small KS, Brosnan MJ, Mohney RP, Spector TD, Valdes AM
Abstract
OBJECTIVE: Abdominal obesity is associated with increased risk of type 2 diabetes (T2D) and cardiovascular disease. The aim of this study was to assess whether metabolomic markers of T2D and blood pressure (BP) act on these traits via visceral fat (VF) mass.
METHODS: Metabolomic profiling of 280 fasting plasma metabolites was conducted on 2,401 women from TwinsUK. The overlap was assessed between published metabolites associated with T2D, insulin resistance, or BP and those that were identified to be associated with VF (after adjustment for covariates) measured by dual-energy X-ray absorptiometry.
RESULTS: In addition to glucose, six metabolites were strongly associated with both VF mass and T2D: lactate and branched-chain amino acids, all of them related to metabolism and the tricarboxylic acid cycle; on average, 38.5% of their association with insulin resistance was mediated by their association with VF mass. Five metabolites were associated with BP and VF mass including the inflammation-associated peptide HWESASXX, the steroid hormone androstenedione, lactate, and palmitate. On average, 29% of their effect on BP was mediated by their association with VF mass.
CONCLUSIONS: Little overlap was found between the metabolites associated with BP and those associated with insulin resistance via VF mass.
PMID: 27129722 [PubMed - indexed for MEDLINE]
Early lipid changes in acute kidney injury using SWATH lipidomics coupled with MALDI tissue imaging.
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Early lipid changes in acute kidney injury using SWATH lipidomics coupled with MALDI tissue imaging.
Am J Physiol Renal Physiol. 2016 May 15;310(10):F1136-47
Authors: Rao S, Walters KB, Wilson L, Chen B, Bolisetty S, Graves D, Barnes S, Agarwal A, Kabarowski JH
Abstract
Acute kidney injury (AKI) is one of the leading causes of in-hospital morbidity and mortality, particularly in critically ill patients. Although our understanding of AKI at the molecular level remains limited due to its complex pathophysiology, recent advances in both quantitative and spatial mass spectrometric approaches offer new opportunities to assess the significance of renal metabolomic changes in AKI models. In this study, we evaluated lipid changes in early ischemia-reperfusion (IR)-related AKI in mice by using sequential window acquisition of all theoretical spectra (SWATH)-mass spectrometry (MS) lipidomics. We found a significant increase in two abundant ether-linked phospholipids following IR at 6 h postinjury, a plasmanyl choline, phosphatidylcholine (PC) O-38:1 (O-18:0, 20:1), and a plasmalogen, phosphatidylethanolamine (PE) O-42:3 (O-20:1, 22:2). Both of these lipids correlated with the severity of AKI as measured by plasma creatinine. In addition to many more renal lipid changes associated with more severe AKI, PC O-38:1 elevations were maintained at 24 h post-IR, while renal PE O-42:3 levels decreased, as were all ether PEs detected by SWATH-MS at this later time point. To further assess the significance of this early increase in PC O-38:1, we used matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) to determine that it occurred in proximal tubules, a region of the kidney that is most prone to IR injury and also rich in the rate-limiting enzymes involved in ether-linked phospholipid biosynthesis. Use of SWATH-MS lipidomics in conjunction with MALDI-IMS for lipid localization will help in elucidating the role of lipids in the pathobiology of AKI.
PMID: 26911846 [PubMed - indexed for MEDLINE]
metabolomics; +24 new citations
24 new pubmed citations were retrieved for your search.
Click on the search hyperlink below to display the complete search results:
metabolomics
These pubmed results were generated on 2017/06/27PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books.
Citations may include links to full-text content from PubMed Central and publisher web sites.
Systematic biobanking, novel imaging techniques, and advanced molecular analysis for precise tumor diagnosis and therapy: The Polish MOBIT project.
Systematic biobanking, novel imaging techniques, and advanced molecular analysis for precise tumor diagnosis and therapy: The Polish MOBIT project.
Adv Med Sci. 2017 Jun 21;62(2):405-413
Authors: Niklinski J, Kretowski A, Moniuszko M, Reszec J, Michalska-Falkowska A, Niemira M, Ciborowski M, Charkiewicz R, Jurgilewicz D, Kozlowski M, Ramlau R, Piwkowski C, Kwasniewski M, Kaczmarek M, Ciereszko A, Wasniewski T, Mroz R, Naumnik W, Sierko E, Paczkowska M, Kisluk J, Sulewska A, Cybulski A, Mariak Z, Kedra B, Szamatowicz J, Kurzawa P, Minarowski L, Charkiewicz AE, Mroczko B, Malyszko J, Manegold C, Pilz L, Allgayer H, Abba ML, Juhl H, Koch F, MOBIT Study Group
Abstract
Personalized and precision medicine is gaining recognition due to the limitations by standard diagnosis and treatment; many areas of medicine, from cancer to psychiatry, are moving towards tailored and individualized treatment for patients based on their clinical characteristics and genetic signatures as well as novel imaging techniques. Advances in whole genome sequencing have led to identification of genes involved in a variety of diseases. Moreover, biomarkers indicating severity of disease or susceptibility to treatment are increasingly being characterized. The continued identification of new genes and biomarkers specific to disease subtypes and individual patients is essential and inevitable for translation into personalized medicine, in estimating both, disease risk and response to therapy. Taking into consideration the mostly unsolved necessity of tailored therapy in oncology the innovative project MOBIT (molecular biomarkers for individualized therapy) was designed. The aims of the project are: (i) establishing integrative management of precise tumor diagnosis and therapy including systematic biobanking, novel imaging techniques, and advanced molecular analysis by collecting comprehensive tumor tissues, liquid biopsies (whole blood, serum, plasma), and urine specimens (supernatant; sediment) as well as (ii) developing personalized lung cancer diagnostics based on tumor heterogeneity and integrated genomics, transcriptomics, metabolomics, and radiomics PET/MRI analysis. It will consist of 5 work packages. In this paper the rationale of the Polish MOBIT project as well as its design is presented. (iii) The project is to draw interest in and to invite national and international, private and public, preclinical and clinical initiatives to establish individualized and precise procedures for integrating novel targeted therapies and advanced imaging techniques.
PMID: 28646744 [PubMed - as supplied by publisher]
Metabolomics of Diabetes in Pregnancy.
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Metabolomics of Diabetes in Pregnancy.
Curr Diab Rep. 2017 Aug;17(8):57
Authors: McCabe CF, Perng W
Abstract
PURPOSE OF REVIEW: The purpose of this review is to describe ways in which metabolomics may enhance understanding of gestational diabetes mellitus (GDM) etiology and refine current diagnostic criteria.
RECENT FINDINGS: Current clinical recommendations suggest screening for GDM between 24 and 28 of gestational weeks using an oral glucose tolerance test. Despite this consensus, there are discrepancies regarding the exact criteria for GDM diagnosis. Further, emerging evidence has unveiled heterogeneous physiological pathways underlying GDM-specifically, GDM with defective insulin secretion vs. sensitivity-that have important implications for disease diagnosis and management. The objectives of this review are threefold. First, we seek to provide a brief summary of current knowledge regarding GDM pathophysiology. Next, we describe the potential role of metabolomics to refine and improve the prediction, screening, and diagnosis of GDM. Finally, we propose ways in which metabolomics may eventually impact clinical care and risk assessment for GDM and its comorbidities.
PMID: 28646358 [PubMed - in process]
Chemotherapy-induced gastrointestinal toxicity is associated with changes in serum and urine metabolome and fecal microbiota in male Sprague-Dawley rats.
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Chemotherapy-induced gastrointestinal toxicity is associated with changes in serum and urine metabolome and fecal microbiota in male Sprague-Dawley rats.
Cancer Chemother Pharmacol. 2017 Jun 23;:
Authors: Forsgård RA, Marrachelli VG, Korpela K, Frias R, Collado MC, Korpela R, Monleon D, Spillmann T, Österlund P
Abstract
PURPOSE: Chemotherapy-induced gastrointestinal toxicity (CIGT) is a complex process that involves multiple pathophysiological mechanisms. We have previously shown that commonly used chemotherapeutics 5-fluorouracil, oxaliplatin, and irinotecan damage the intestinal mucosa and increase intestinal permeability to iohexol. We hypothesized that CIGT is associated with alterations in fecal microbiota and metabolome. Our aim was to characterize these changes and examine how they relate to the severity of CIGT.
METHODS: A total of 48 male Sprague-Dawley rats were injected intraperitoneally either with 5-fluorouracil (150 mg/kg), oxaliplatin (15 mg/kg), or irinotecan (200 mg/kg). Body weight change was measured daily after drug administration and the animals were euthanized after 72 h. Blood, urine, and fecal samples were collected at baseline and at the end of the experiment. The changes in the composition of fecal microbiota were analyzed with 16S rRNA gene sequencing. Metabolic changes in serum and urine metabolome were measured with 1 mm proton nuclear magnetic resonance ((1)H-NMR).
RESULTS: Irinotecan increased the relative abundance of Fusobacteria and Proteobacteria, while 5-FU and oxaliplatin caused only minor changes in the composition of fecal microbiota. All chemotherapeutics increased the levels of serum fatty acids and N(CH3)3 moieties and decreased the levels of Krebs cycle metabolites and free amino acids.
CONCLUSIONS: Chemotherapeutic drugs, 5-fluorouracil, oxaliplatin, and irinotecan, induce several microbial and metabolic changes which may play a role in the pathophysiology of CIGT. The observed changes in intestinal permeability, fecal microbiota, and metabolome suggest the activation of inflammatory processes.
PMID: 28646338 [PubMed - as supplied by publisher]
Metabolic Reprogramming via PPARα Signaling in Cardiac Hypertrophy and Failure From Metabolomics to Epigenetics.
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Metabolic Reprogramming via PPARα Signaling in Cardiac Hypertrophy and Failure From Metabolomics to Epigenetics.
Am J Physiol Heart Circ Physiol. 2017 Jun 23;:ajpheart.00103.2017
Authors: Warren JS, Oka SI, Zablocki D, Sadoshima J
Abstract
Studies using -omics-based approaches have advanced our knowledge of metabolic remodeling in cardiac hypertrophy and failure. Metabolomic analysis of the failing heart has revealed global changes in mitochondrial substrate metabolism. Peroxisome proliferator-activated receptor alpha (PPARα) plays a critical role in synergistic regulation of cardiac metabolism through transcriptional control. Metabolic reprogramming via PPARα signaling in heart failure ultimately propagates into myocardial energetics. However, emerging evidence suggests that the expression level of PPARα per se does not always explain the energetic state in the heart. The transcriptional activities of PPARα are dynamic, yet highly coordinated. An additional level of complexity in the PPARα regulatory mechanism arises from its ability to interact with various partners, which ultimately determines the metabolic phenotype of the diseased heart. This review summarizes our current knowledge of the PPARα regulatory mechanisms in cardiac metabolism and the possible role of PPARα in epigenetic modifications in the diseased heart. In addition, we discuss how metabolomics can contribute to a better understanding of the role of PPARα in the progression of cardiac hypertrophy and failure.
PMID: 28646024 [PubMed - as supplied by publisher]
Vitamin E deficiency during embryogenesis in zebrafish causes lasting metabolic and cognitive impairments despite refeeding adequate diets.
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Vitamin E deficiency during embryogenesis in zebrafish causes lasting metabolic and cognitive impairments despite refeeding adequate diets.
Free Radic Biol Med. 2017 Jun 20;:
Authors: McDougall M, Choi J, Truong L, Tanguay R, Traber MG
Abstract
Vitamin E (α-tocopherol; VitE) is a lipophilic antioxidant required for normal embryonic development in vertebrates, but the long-term effects of embryonic VitE deficiency, and whether they are ameliorated by feeding VitE-adequate diets, remain unknown. We addressed these questions using a zebrafish (Danio rerio) model of developmental VitE deficiency followed by dietary remediation. Adult zebrafish maintained on VitE-deficient (E-) or sufficient (E+) diets were spawned to obtained E- and E+ embryos, respectively, which we evaluated up to 12 days post-fertilization (dpf). The E- group suffered significantly increased morbidity and mortality as well as altered DNA methylation status through 5 dpf when compared to E+ larvae, but upon feeding with a VitE-adequate diet from 5-12 dpf both the E- and E+ groups survived and grew normally; the DNA methylation profile also was similar between groups by 12 dpf. However, 12 dpf E- larvae still had behavioral defects. These observations coincided with sustained VitE deficiency in the E- vs. E+ larvae (p< 0.0001), despite adequate dietary supplementation. We also found in E- vs. E+ larvae continued docosahexaenoic acid (DHA) depletion (p< 0.0001) and significantly increased lipid peroxidation. Further, targeted metabolomics analyses revealed persistent dysregulation of the cellular antioxidant network, the CDP-choline pathway, and glucose metabolism. While anaerobic processes were increased, aerobic metabolism was decreased in the E- vs. E+ larvae, indicating mitochondrial damage. Taken together, these outcomes suggest embryonic VitE deficiency causes lasting behavioral impairments due to persistent lipid peroxidation and metabolic perturbations that are not resolved via later dietary VitE supplementation.
PMID: 28645790 [PubMed - as supplied by publisher]
AKR1C3-mediated adipose androgen generation drives lipotoxicity in women with polycystic ovary syndrome.
Related Articles
AKR1C3-mediated adipose androgen generation drives lipotoxicity in women with polycystic ovary syndrome.
J Clin Endocrinol Metab. 2017 Jun 22;:
Authors: O'Reilly MW, Kempegowda P, Walsh M, Taylor AE, Manolopoulos KN, Allwood JW, Semple RK, Hebenstreit D, Dunn WB, Tomlinson JW, Arlt W
Abstract
Context: Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder, occurring in up to 10% of women of reproductive age. PCOS is associated with insulin resistance and cardiovascular risk. Androgen excess is a defining feature of PCOS and has been suggested as causally associated with insulin resistance; however, mechanistic evidence linking both is lacking. We hypothesized that adipose tissue is an important site linking androgen activation and metabolic dysfunction in PCOS.
Methods: We performed a human deep metabolic in vivo phenotyping study, examining the systemic and intra-adipose effects of acute and chronic androgen exposure in ten PCOS women, in comparison to ten body mass index-matched healthy controls, complemented by in vitro experiments.
Results: PCOS women had increased intra-adipose concentrations of testosterone (p=0.0006) and dihydrotestosterone (p=0.01), with increased expression of the androgen-activating enzyme aldo-ketoreductase type 1 C3 (AKR1C3, p=0.04) in subcutaneous adipose tissue. Adipose glycerol levels in subcutaneous adipose tissue microdialysate supported in vivo suppression of lipolysis after acute androgen exposure in PCOS (p=0.04). Mirroring this, non-targeted serum metabolomics revealed pro-lipogenic effects of androgens in PCOS women only. In vitro studies showed that insulin increased adipose AKR1C3 expression and activity while androgen exposure increased adipocyte de novo lipid synthesis. Pharmacological AKR1C3 inhibition in vitro decreased de novo lipogenesis.
Conclusions: These findings define a novel intra-adipose mechanism of androgen activation that contributes to adipose remodelling and a systemic lipotoxic metabolome, with intra-adipose androgens driving lipid accumulation and insulin resistance in PCOS. AKR1C3 represents a promising novel therapeutic target in PCOS.
PMID: 28645211 [PubMed - as supplied by publisher]
System-wide analysis of short-term response to high temperature in Pinus radiata.
Related Articles
System-wide analysis of short-term response to high temperature in Pinus radiata.
J Exp Bot. 2017 Jun 22;:
Authors: Escandón M, Valledor L, Pascual J, Pinto G, Cañal MJ, Meijón M
Abstract
Pinus radiata seedlings, the most widely planted pine species in the world, were exposed to temperatures within a range mimicking future scenarios based on current models of heat increase. The short-term heat response in P. radiata was studied in detail by exploring the metabolome, proteome and targeted transcriptome. The use of complementary mass spectrometry techniques, GC-MS and LC-Orbitrap-MS, together with novel bioinformatics tools allowed the reliable quantification of 2,075 metabolites and 901 protein groups. Integrative analyses of different functional levels and plant physiological status revealed a complex molecular interaction network of positive and negative correlations between proteins and metabolites involved in short-term heat response, including three main physiological functions as: 1) A hormone subnetwork, where fatty acids, flavonoids and hormones presented a key role; 2) An oxidoreductase subnetwork, including several dehydrogenase and peroxidase proteins; and 3) A heat shock protein subnetwork, with numerous proteins that contain a HSP20 domain, all of which were overexpressed at the transcriptional level. Integrated analysis pinpointed the basic mechanisms underlying the short-term physiological reaction of P. radiata during heat response. This approach was feasible in forest species and unmasked two novel candidate biomarkers of heat resistance, PHO1 and TRANSCRIPTION FACTOR APFI, and a MITOCHONDRIAL SMALL HEAT SHOCK PROTEIN, for use in future breeding programs.
PMID: 28645179 [PubMed - as supplied by publisher]
metabolomics; +33 new citations
33 new pubmed citations were retrieved for your search.
Click on the search hyperlink below to display the complete search results:
metabolomics
These pubmed results were generated on 2017/06/24PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books.
Citations may include links to full-text content from PubMed Central and publisher web sites.
Covalent attachment and Pro-Pro endopeptidase (PPEP-1)-mediated release of Clostridium difficile cell surface proteins involved in adhesion.
Covalent attachment and Pro-Pro endopeptidase (PPEP-1)-mediated release of Clostridium difficile cell surface proteins involved in adhesion.
Mol Microbiol. 2017 Jun 21;:
Authors: Corver J, Cordo' V, van Leeuwen HC, Klychnikov OI, Hensbergen PJ
Abstract
In the past decade, Clostridium difficile has emerged as an important gut pathogen. This anaerobic, Gram-positive bacterium is the main cause of infectious nosocomial diarrhea. Whereas much is known about the mechanism through which the C. difficile toxins cause diarrhea, relatively little is known about the dynamics of adhesion and motility, which is mediated by cell surface proteins. This review will discuss the recent advances in our understanding of the sortase-mediated covalent attachment of cell surface (adhesion) proteins to the peptidoglycan layer of C. difficile and their release through the action of a highly specific secreted metalloprotease (Pro-Pro endopeptidase 1, PPEP-1). Specific emphasis will be on a model in which PPEP-1 and its substrates control the switch from a sessile to motile phenotype in C. difficile, and how this is regulated by the cyclic dinucleotide c-di-GMP (3'-5' cyclic dimeric guanosine monophosphate). This article is protected by copyright. All rights reserved.
PMID: 28636257 [PubMed - as supplied by publisher]
Evaluation of Classifier Performance for Multiclass Phenotype Discrimination in Untargeted Metabolomics.
Evaluation of Classifier Performance for Multiclass Phenotype Discrimination in Untargeted Metabolomics.
Metabolites. 2017 Jun 21;7(2):
Authors: Trainor PJ, DeFilippis AP, Rai SN
Abstract
Statistical classification is a critical component of utilizing metabolomics data for examining the molecular determinants of phenotypes. Despite this, a comprehensive and rigorous evaluation of the accuracy of classification techniques for phenotype discrimination given metabolomics data has not been conducted. We conducted such an evaluation using both simulated and real metabolomics datasets, comparing Partial Least Squares-Discriminant Analysis (PLS-DA), Sparse PLS-DA, Random Forests, Support Vector Machines (SVM), Artificial Neural Network, k-Nearest Neighbors (k-NN), and Naïve Bayes classification techniques for discrimination. We evaluated the techniques on simulated data generated to mimic global untargeted metabolomics data by incorporating realistic block-wise correlation and partial correlation structures for mimicking the correlations and metabolite clustering generated by biological processes. Over the simulation studies, covariance structures, means, and effect sizes were stochastically varied to provide consistent estimates of classifier performance over a wide range of possible scenarios. The effects of the presence of non-normal error distributions, the introduction of biological and technical outliers, unbalanced phenotype allocation, missing values due to abundances below a limit of detection, and the effect of prior-significance filtering (dimension reduction) were evaluated via simulation. In each simulation, classifier parameters, such as the number of hidden nodes in a Neural Network, were optimized by cross-validation to minimize the probability of detecting spurious results due to poorly tuned classifiers. Classifier performance was then evaluated using real metabolomics datasets of varying sample medium, sample size, and experimental design. We report that in the most realistic simulation studies that incorporated non-normal error distributions, unbalanced phenotype allocation, outliers, missing values, and dimension reduction, classifier performance (least to greatest error) was ranked as follows: SVM, Random Forest, Naïve Bayes, sPLS-DA, Neural Networks, PLS-DA and k-NN classifiers. When non-normal error distributions were introduced, the performance of PLS-DA and k-NN classifiers deteriorated further relative to the remaining techniques. Over the real datasets, a trend of better performance of SVM and Random Forest classifier performance was observed.
PMID: 28635678 [PubMed - in process]