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Wang K, Zhang C, Zhou H, Wei H, Yin L, Zhang T, Zhi Y, Zhou J, Han B, Zhang Z, Du X. Detection of glucose transporter 1 in living cells for assessment of tumor development and therapy using an electrochemical biosensor. Biosens Bioelectron 2024; 244:115820. [PMID: 37952321 DOI: 10.1016/j.bios.2023.115820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/26/2023] [Accepted: 11/02/2023] [Indexed: 11/14/2023]
Abstract
The expression level of glucose transporter 1 (GLUT-1) is highly correlated with tumor malignancy, making it a promising therapeutic target for cancer treatment. The detection of GLUT-1 expression level is significant for cancer discovery and valuating the efficacy of drug treatments. However, current methods for GLUT-1 detection primarily rely on traditional techniques. Therefore, the development of anon-destructive in vivo monitoring system would be invaluable for assessing GLUT-1 expression and tumor responses to various drugs. In this study, an electrochemical platform for detection of GLUT-1 on living cells was established using reduced graphene oxide-multi-wall carbon nanotube composite (rGO-MWCNT) as a conductive coating and toluidine blue O (TBO)-graphene-gold nanoparticle-GLUT-1 antibody as the electrochemical probe. The sensor demonstrated excellent performance in detecting GLUT-1 on cells with a linear range of 10 - 105 cells/mL, good stability and selectivity. The sensor successfully detected GLUT-1 expressions in multiple tumor cell types, including those treated with siRNA or drugs, and the results were consistent with those obtained from traditional methods such as flow cytometry, western blotting, and immunofluorescence. The sensor is promising in evaluating the malignant level of tumor cells, distinguishing glucose uptake pathways in tumor cells, reducing medical costs, and facilitating the translation of electrochemical sensing technology to the clinical settings.
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Affiliation(s)
- Kaijing Wang
- Department of Hepatobiliary Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Congcong Zhang
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Han Zhou
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Hongshuai Wei
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Liping Yin
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Tingting Zhang
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Yunqing Zhi
- Department of Assisted Reproductive Medicine, Shanghai First Maternity and Infant Hospital, School of Medicine, Tongji University, Shanghai, 200092, China
| | - Jun Zhou
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Bingkai Han
- Tianjin Key Laboratory of Exercise Physiology and Sports Medicine, Institute of Sport, Exercise & Health, Tianjin University of Sport, Tianjin, 300381, China
| | - Zhenguo Zhang
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China.
| | - Xin Du
- Center for Cell Structure and Function, Shandong Provincial Key Laboratory of Animal Resistance Biology, College of Life Sciences, Shandong Normal University, Jinan, Shandong, 250014, China.
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Amorese AJ, Minchew EC, Tarpey MD, Readyoff AT, Williamson NC, Schmidt CA, McMillin SL, Goldberg EJ, Terwilliger ZS, Spangenburg QA, Witczak CA, Brault JJ, Abel ED, McClung JM, Fisher-Wellman KH, Spangenburg EE. Hypoxia Resistance Is an Inherent Phenotype of the Mouse Flexor Digitorum Brevis Skeletal Muscle. FUNCTION 2023; 4:zqad012. [PMID: 37168496 PMCID: PMC10165545 DOI: 10.1093/function/zqad012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/10/2023] [Accepted: 03/13/2023] [Indexed: 05/13/2023] Open
Abstract
The various functions of skeletal muscle (movement, respiration, thermogenesis, etc.) require the presence of oxygen (O2). Inadequate O2 bioavailability (ie, hypoxia) is detrimental to muscle function and, in chronic cases, can result in muscle wasting. Current therapeutic interventions have proven largely ineffective to rescue skeletal muscle from hypoxic damage. However, our lab has identified a mammalian skeletal muscle that maintains proper physiological function in an environment depleted of O2. Using mouse models of in vivo hindlimb ischemia and ex vivo anoxia exposure, we observed the preservation of force production in the flexor digitorum brevis (FDB), while in contrast the extensor digitorum longus (EDL) and soleus muscles suffered loss of force output. Unlike other muscles, we found that the FDB phenotype is not dependent on mitochondria, which partially explains the hypoxia resistance. Muscle proteomes were interrogated using a discovery-based approach, which identified significantly greater expression of the transmembrane glucose transporter GLUT1 in the FDB as compared to the EDL and soleus. Through loss-and-gain-of-function approaches, we determined that GLUT1 is necessary for the FDB to survive hypoxia, but overexpression of GLUT1 was insufficient to rescue other skeletal muscles from hypoxic damage. Collectively, the data demonstrate that the FDB is uniquely resistant to hypoxic insults. Defining the mechanisms that explain the phenotype may provide insight towards developing approaches for preventing hypoxia-induced tissue damage.
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Affiliation(s)
- Adam J Amorese
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Everett C Minchew
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Michael D Tarpey
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Andrew T Readyoff
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC 27834, USA
| | - Nicholas C Williamson
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Cameron A Schmidt
- Department of Biology, East Carolina University, Greenville, NC 27834, USA
| | - Shawna L McMillin
- Department of Kinesiology, East Carolina University, Greenville, NC 27858, USA
| | - Emma J Goldberg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Zoe S Terwilliger
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Quincy A Spangenburg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Carol A Witczak
- Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Center for Musculoskeletal Health, Indianapolis, IN 46202, USA
- Indiana Center for Diabetes and Metabolic Diseases, Indianapolis, IN 46202, USA
| | - Jeffrey J Brault
- Department of Anatomy, Cell Biology, and Physiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Center for Musculoskeletal Health, Indianapolis, IN 46202, USA
| | - E Dale Abel
- David Geffen School of Medicine, Department of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Joseph M McClung
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- East Carolina Diabetes and Obesity Institute, East Carolina University, Greenville, NC 27834, USA
| | - Kelsey H Fisher-Wellman
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
| | - Espen E Spangenburg
- Department of Physiology, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
- Department of Cardiovascular Sciences, Brody School of Medicine, East Carolina University, Greenville, NC 27834, USA
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miR-275/305 cluster is essential for maintaining energy metabolic homeostasis by the insulin signaling pathway in Bactrocera dorsalis. PLoS Genet 2022; 18:e1010418. [PMID: 36197879 PMCID: PMC9534453 DOI: 10.1371/journal.pgen.1010418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 09/07/2022] [Indexed: 11/19/2022] Open
Abstract
Increasing evidence indicates that miRNAs play crucial regulatory roles in various physiological processes of insects, including systemic metabolism. However, the molecular mechanisms of how specific miRNAs regulate energy metabolic homeostasis remain largely unknown. In the present study, we found that an evolutionarily conserved miR-275/305 cluster was essential for maintaining energy metabolic homeostasis in response to dietary yeast stimulation in Bactrocera dorsalis. Depletion of miR-275 and miR-305 by the CRISPR/Cas9 system significantly reduced triglyceride and glycogen contents, elevated total sugar levels, and impaired flight capacity. Combined in vivo and in vitro experiments, we demonstrated that miR-275 and miR-305 can bind to the 3'UTR regions of SLC2A1 and GLIS2 to repress their expression, respectively. RNAi-mediated knockdown of these two genes partially rescued metabolic phenotypes caused by inhibiting miR-275 and miR-305. Furthermore, we further illustrated that the miR-275/305 cluster acting as a regulator of the metabolic axis was controlled by the insulin signaling pathway. In conclusion, our work combined genetic and physiological approaches to clarify the molecular mechanism of metabolic homeostasis in response to different dietary stimulations and provided a reference for deciphering the potential targets of physiologically important miRNAs in a non-model organism.
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Schoch S, Iacopini D, Dalla Pozza M, Di Pietro S, Degano I, Gasser G, Di Bussolo V, Marchetti F. Tethering Carbohydrates to the Vinyliminium Ligand of Antiproliferative Organometallic Diiron Complexes. Organometallics 2022; 41:514-526. [PMID: 35308582 PMCID: PMC8924928 DOI: 10.1021/acs.organomet.1c00519] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Indexed: 12/23/2022]
Affiliation(s)
- Silvia Schoch
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy
| | - Dalila Iacopini
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy
| | - Maria Dalla Pozza
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, 75005 Paris, France
| | | | - Ilaria Degano
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy
| | - Gilles Gasser
- Chimie ParisTech, PSL University, CNRS, Institute of Chemistry for Life and Health Sciences, 75005 Paris, France
| | | | - Fabio Marchetti
- Department of Chemistry and Industrial Chemistry, University of Pisa, 56124 Pisa, Italy
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Godsman N, Kohlhaas M, Nickel A, Cheyne L, Mingarelli M, Schweiger L, Hepburn C, Munts C, Welch A, Delibegovic M, Van Bilsen M, Maack C, Dawson DK. Metabolic alterations in a rat model of Takotsubo syndrome. Cardiovasc Res 2021; 118:1932-1946. [PMID: 33711093 PMCID: PMC9239582 DOI: 10.1093/cvr/cvab081] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 03/09/2021] [Indexed: 12/16/2022] Open
Abstract
AIMS Cardiac energetic impairment is a major finding in takotsubo patients. We investigate specific metabolic adaptations to direct future therapies. METHODS AND RESULTS An isoprenaline-injection female rat model (versus sham) was studied at day-3; recovery assessed at day-7. Substrate uptake, metabolism, inflammation and remodelling were investigated by 18F-FDG-PET, metabolomics, qPCR and WB. Isolated cardiomyocytes were patch-clamped during stress protocols for redox states of NAD(P)H/FAD or [Ca2+]c, [Ca2+]m and sarcomere length. Mitochondrial respiration was assessed by seahorse/Clark electrode (glycolytic and β-oxidation substrates).Cardiac 18F-FDG metabolic rate was increased in takotsubo (p = 0.006), as were expression of GLUT4-RNA/GLUT1/HK2-RNA and HK activity (all p < 0.05), with concomitant accumulation of glucose- and fructose-6-phosphates (p > 0.0001). Both lactate and pyruvate were lower (p < 0.05) despite increases in LDH-RNA and PDH (p < 0.05 both). β-oxidation enzymes CPT1b-RNA and 3KAT were increased (p < 0.01) but malonyl-CoA (CPT-1 regulator) was upregulated (p = 0.01) with decreased fatty acids and acyl-carnitines levels (p = 0.0001-0.02). Krebs cycle intermediates α-ketoglutarate and succinyl-carnitine were reduced (p < 0.05) as was cellular ATP reporter dihydroorotate (p = 0.003). Mitochondrial Ca2+ uptake during high workload was impaired on day-3 (p < 0.0001), inducing oxidation of NAD(P)H and FAD (p = 0.03) but resolved by day-7. There were no differences in mitochondrial respiratory function, sarcomere shortening or [Ca2+] transients of isolated cardiomyocytes, implying preserved integrity of both mitochondria and cardiomyocyte. Inflammation and remodelling were upregulated - increased CD68-RNA, collagen RNA/protein and skeletal actin RNA (all p < 0.05). CONCLUSION Dys-regulation of glucose and lipid metabolic pathways with decreases in final glycolytic and β-oxidation metabolites and reduced availability of Krebs intermediates characterises takotsubo myocardium. The energetic deficit accompanies defective Ca2+ handling, inflammation and upregulation of remodelling pathways, with preservation of sarcomeric and mitochondrial integrity. TRANSLATIONAL PERSPECTIVE The simultaneous dysregulation in the glycolytic and beta-oxidation pathways which underlies the energetic deficit of the takotsubo heart supports further testing of currently available metabolic modulators as possible candidates for successful therapy, as well as targeting the inflammatory and remodelling pathways.
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Affiliation(s)
- Nadine Godsman
- Aberdeen Cardiovascular and Diabetes Centre, University of Aberdeen, Aberdeen, United Kingdom
| | | | | | - Lesley Cheyne
- Aberdeen Cardiovascular and Diabetes Centre, University of Aberdeen, Aberdeen, United Kingdom
| | - Marco Mingarelli
- Biomedical physics, University of Aberdeen, Aberdeen, United Kingdom
| | - Lutz Schweiger
- John Mallard Scottish P.E.T. Centre, University of Aberdeen, Aberdeen, United Kingdom
| | - Claire Hepburn
- Aberdeen Cardiovascular and Diabetes Centre, University of Aberdeen, Aberdeen, United Kingdom
| | - Chantal Munts
- School for Cardiovascular Diseases, Faculty of Health, Medicine and Life Sciences Maastricht University, Netherlands
| | - Andy Welch
- Biomedical physics, University of Aberdeen, Aberdeen, United Kingdom
| | - Mirela Delibegovic
- Aberdeen Cardiovascular and Diabetes Centre, University of Aberdeen, Aberdeen, United Kingdom
| | - Marc Van Bilsen
- School for Cardiovascular Diseases, Faculty of Health, Medicine and Life Sciences Maastricht University, Netherlands
| | - Christoph Maack
- Comprehensive Heart Failure Center (CHFC), Würzburg, Germany
| | - Dana K Dawson
- Aberdeen Cardiovascular and Diabetes Centre, University of Aberdeen, Aberdeen, United Kingdom
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6
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van der Kooij MA. The impact of chronic stress on energy metabolism. Mol Cell Neurosci 2020; 107:103525. [PMID: 32629109 DOI: 10.1016/j.mcn.2020.103525] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 06/02/2020] [Accepted: 06/16/2020] [Indexed: 01/21/2023] Open
Abstract
The brain is exceptionally demanding in terms of energy metabolism. Approximately 20% of the calories consumed are devoted to our cerebral faculties, with the lion's share provided in the form of glucose. The brain's stringent energy dependency requires a high degree of harmonization between the elements responsible for supplying- and metabolizing energetic substrates. However, chronic stress may jeopardize this homeostatic energy balance by disruption of critical metabolic processes. In agreement, stress-related mental disorders have been linked with perturbations in energy metabolism. Prominent stress-induced metabolic alterations include the actions of hormones, glucose uptake and mitochondrial adjustments. Importantly, fundamental stress-responsive metabolic adjustments in humans and animal models bear a striking resemblance. Here, an overview is provided of key findings, demonstrating the pervasive impact of chronic stress on energy metabolism. Furthermore, I argue that medications, aimed primarily at restoring metabolic homeostasis, may constitute a novel approach to treat mental disorders.
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Pharmacologic inhibition of N-linked glycan trimming with kifunensine disrupts GLUT1 trafficking and glucose uptake. Biochimie 2020; 174:18-29. [PMID: 32298759 DOI: 10.1016/j.biochi.2020.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/26/2020] [Accepted: 04/06/2020] [Indexed: 02/06/2023]
Abstract
The facilitative glucose transport GLUT1 (SLC2A1) is a constitutively expressed membrane protein involved in basal uptake of blood glucose. GLUT1 modification by N-linked glycosylation at a single asparagine residue (N45) appears to play multiple roles in the trafficking, stability and transport activity of this protein. Here we examine the role of complex N-glycosylation on GLUT1 function in renal epithelial cells by arresting this modification at the high-mannose stage with the mannosidase I inhibitor kifunensine. Consistent with prior work in which GLUT1 glycosylation was completely inhibited, we find that kifunensine treatment results in a time-dependent decrease of up to 40% in cellular glucose uptake. We further demonstrate that this effect is primarily a result of deficient GLUT1 trafficking to the cell membrane due to quality control mechanisms that instead direct GLUT1 to the ER-associated degradation (ERAD) pathway. Unlike tunicamycin, which inhibits the first step in N-glycosyl transfer and causes dramatic cell cycle arrest, kifunensine causes only a modest decrease in GLUT1 levels and cell cycle progression in both normal and transformed renal cells. The effect of kifunensine on the cell cycle appears to be independent of its effect on GLUT1, since all renal cell types in this study displayed decreased proliferation regardless of their dependence on glucose uptake for growth and survival. Together these results indicate that proper N-glycan processing plays an important role in directing GLUT1 to the cell surface and that disruption of mannosidase activity results in aberrant degradation of GLUT1 by the ERAD pathway.
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Pitman KE, Alluri SR, Kristian A, Aarnes EK, Lyng H, Riss PJ, Malinen E. Influx rate of 18F-fluoroaminosuberic acid reflects cystine/glutamate antiporter expression in tumour xenografts. Eur J Nucl Med Mol Imaging 2019; 46:2190-2198. [PMID: 31264167 DOI: 10.1007/s00259-019-04375-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/27/2019] [Indexed: 02/06/2023]
Abstract
PURPOSE 18F-fluoroaminosuberic acid (18F-FASu) is a recently developed amino acid tracer for positron emission tomography (PET) of oxidative stress that may offer improved tumour assessment over the conventional tracer 18F-fluorodeoxyglucose (18F-FDG). Our aim was to evaluate and relate dynamic 18F-FASu and 18F-FDG uptake with pharmacokinetic modelling to transporter protein expression levels in a panel of diverse tumour xenograft lines. METHODS Four different tumour xenograft lines were implanted in female athymic nude mice: MAS98.12 and HBCx3 (breast), TPMX (osteosarcoma) and A549 (lung). Dynamic PET over 60 min was performed on a small animal unit. The time-activity curves (TACs) for 18F-FASu and 18F-FDG in individual tumours were used to extract early (SUVE; 2 min p.i.) and late (SUVL; 55 min p.i.) standardised uptake values. Pharmacokinetic two-tissue compartment models were applied to the TACs to estimate rate constants K1-k4 and blood volume fraction vB. Relative levels of cystine/glutamate antiporter subunit xCT were assessed by western blotting, and expression of GLUT1 and CD31 by immunohistochemistry. RESULTS 18F-FASu showed higher SUVE, whilst 18F-FDG exhibited higher SUVL. Influx rate K1 for 18F-FASu was significantly correlated with xCT levels (p = 0.001) and was significantly higher than K1 for 18F-FDG (p < 0.001). K1 for 18F-FDG was significantly correlated with GLUT1 levels (p = 0.002). vB estimated from 18F-FASu and 18F-FDG TACs was highly consistent and significantly correlated (r = 0.85, p < 0.001). Two qualitatively different 18F-FASu uptake profiles were identified: type α with low xCT expression and low K1 (A549 and HBCx3), and type β with high xCT expression and high K1 (MAS98.12 and TPMX). CONCLUSION The influx rate of 18F-FASu reflects xCT activity in tumour xenografts. Dynamic PET with pharmacokinetic modelling is needed to fully appraise 18F-FASu distribution routes.
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Affiliation(s)
- Kathinka E Pitman
- Department of Physics, University of Oslo, P.O. Box 1048 Blindern, 0316, Oslo, Norway
- Department of Medical Physics, Oslo University Hospital, Oslo, Norway
| | - Santosh R Alluri
- Department of Chemistry, University of Oslo, P.O. Box 1048 Blindern, 0316, Oslo, Norway
| | | | | | - Heidi Lyng
- Department of Radiation Biology, Oslo University Hospital, Oslo, Norway
| | - Patrick J Riss
- Department of Chemistry, University of Oslo, P.O. Box 1048 Blindern, 0316, Oslo, Norway
| | - Eirik Malinen
- Department of Physics, University of Oslo, P.O. Box 1048 Blindern, 0316, Oslo, Norway.
- Department of Medical Physics, Oslo University Hospital, Oslo, Norway.
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Abdul Razzak R, Florence GJ, Gunn-Moore FJ. Approaches to CNS Drug Delivery with a Focus on Transporter-Mediated Transcytosis. Int J Mol Sci 2019; 20:E3108. [PMID: 31242683 PMCID: PMC6627589 DOI: 10.3390/ijms20123108] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/15/2019] [Accepted: 06/16/2019] [Indexed: 12/13/2022] Open
Abstract
Drug delivery to the central nervous system (CNS) conferred by brain barriers is a major obstacle in the development of effective neurotherapeutics. In this review, a classification of current approaches of clinical or investigational importance for the delivery of therapeutics to the CNS is presented. This classification includes the use of formulations administered systemically that can elicit transcytosis-mediated transport by interacting with transporters expressed by transvascular endothelial cells. Neurotherapeutics can also be delivered to the CNS by means of surgical intervention using specialized catheters or implantable reservoirs. Strategies for delivering drugs to the CNS have evolved tremendously during the last two decades, yet, some factors can affect the quality of data generated in preclinical investigation, which can hamper the extension of the applications of these strategies into clinically useful tools. Here, we disclose some of these factors and propose some solutions that may prove valuable at bridging the gap between preclinical findings and clinical trials.
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Affiliation(s)
- Rana Abdul Razzak
- Medical and Biological Sciences Building, School of Biology, University of St Andrews, St Andrews KY16 9TF, UK.
- Biomedical Science Research Centre, Schools of Chemistry and Biology, University of St Andrews, St Andrews KY16 9TF, UK.
| | - Gordon J Florence
- Biomedical Science Research Centre, Schools of Chemistry and Biology, University of St Andrews, St Andrews KY16 9TF, UK.
| | - Frank J Gunn-Moore
- Medical and Biological Sciences Building, School of Biology, University of St Andrews, St Andrews KY16 9TF, UK.
- Biomedical Science Research Centre, Schools of Chemistry and Biology, University of St Andrews, St Andrews KY16 9TF, UK.
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Boonanuntanasarn S, Nakharuthai C, Schrama D, Duangkaew R, Rodrigues PM. Effects of dietary lipid sources on hepatic nutritive contents, fatty acid composition and proteome of Nile tilapia (Oreochromis niloticus). J Proteomics 2019; 192:208-222. [DOI: 10.1016/j.jprot.2018.09.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 08/05/2018] [Accepted: 09/03/2018] [Indexed: 01/09/2023]
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Chronic social stress-induced hyperglycemia in mice couples individual stress susceptibility to impaired spatial memory. Proc Natl Acad Sci U S A 2018; 115:E10187-E10196. [PMID: 30301805 PMCID: PMC6205456 DOI: 10.1073/pnas.1804412115] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Stress-associated mental disorders and diabetes pose an enormous socio-economic burden. Glucose dysregulation occurs with both psychosocial and metabolic stress. While cognitive impairments are common in metabolic disorders such as diabetes and are accompanied by hyperglycemia, a causal role for glucose has not been established. We show that chronic social defeat (CSD) stress induces lasting peripheral and central hyperglycemia and impaired glucose metabolism in a subgroup of mice. Animals exhibiting hyperglycemia early post-CSD display spatial memory impairments that can be rescued by the antidiabetic empagliflozin. We demonstrate that individual stress vulnerability to glucose homeostasis can be identified early after insult and that stress-induced hyperglycemia directly impinges on cognitive integrity. Our findings further bridge the gap between stress-related pathologies and metabolic disorders. Stringent glucose demands render the brain susceptible to disturbances in the supply of this main source of energy, and chronic stress may constitute such a disruption. However, whether stress-associated cognitive impairments may arise from disturbed glucose regulation remains unclear. Here we show that chronic social defeat (CSD) stress in adult male mice induces hyperglycemia and directly affects spatial memory performance. Stressed mice developed hyperglycemia and impaired glucose metabolism peripherally as well as in the brain (demonstrated by PET and induced metabolic bioluminescence imaging), which was accompanied by hippocampus-related spatial memory impairments. Importantly, the cognitive and metabolic phenotype pertained to a subset of stressed mice and could be linked to early hyperglycemia 2 days post-CSD. Based on this criterion, ∼40% of the stressed mice had a high-glucose (glucose >150 mg/dL), stress-susceptible phenotype. The relevance of this biomarker emerges from the effects of the glucose-lowering sodium glucose cotransporter 2 inhibitor empagliflozin, because upon dietary treatment, mice identified as having high glucose demonstrated restored spatial memory and normalized glucose metabolism. Conversely, reducing glucose levels by empagliflozin in mice that did not display stress-induced hyperglycemia (resilient mice) impaired their default-intact spatial memory performance. We conclude that hyperglycemia developing early after chronic stress threatens long-term glucose homeostasis and causes spatial memory dysfunction. Our findings may explain the comorbidity between stress-related and metabolic disorders, such as depression and diabetes, and suggest that cognitive impairments in both types of disorders could originate from excessive cerebral glucose accumulation.
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Toyoda Y, Akarlar B, Sarov M, Ozlu N, Saitoh S. Extracellular glucose level regulates dependence on
GRP
78 for cell surface localization of multipass transmembrane proteins in HeLa cells. FEBS Lett 2018; 592:3295-3304. [DOI: 10.1002/1873-3468.13232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 08/20/2018] [Accepted: 08/21/2018] [Indexed: 12/18/2022]
Affiliation(s)
| | - Busra Akarlar
- Department of Molecular Biology and Genetics Koc University Istanbul Turkey
| | - Mihail Sarov
- Max Planck Institute of Molecular Cell Biology and Genetics Dresden Germany
| | - Nurhan Ozlu
- Department of Molecular Biology and Genetics Koc University Istanbul Turkey
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Quercetin inhibits glucose transport by binding to an exofacial site on GLUT1. Biochimie 2018; 151:107-114. [PMID: 29857184 DOI: 10.1016/j.biochi.2018.05.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 05/25/2018] [Indexed: 12/27/2022]
Abstract
Quercetin, a common dietary flavone, is a competitive inhibitor of glucose uptake and is also thought to be transported into cells by GLUT1. In this study, we confirm that quercetin is a competitive inhibitor of GLUT1 and also demonstrate that newly synthesized compounds, WZB-117 and BAY-876 are robust inhibitors of GLUT1 in L929 cells. To measure quercetin interaction with L929 cells, we develop a new fluorescent assay using flow cytometry. The binding of quercetin and its inhibitory effects on 2-deoxyglucose (2DG) uptake showed nearly identical dose dependent effects, with both having maximum effects between 50 and 100 μM and similar half maximum effects at 8.9 and 8.5 μM respectively. The interaction of quercetin was rapid with t1/2 of 54 s and the onset and loss of its inhibitory effects on 2DG uptake were equally fast. This suggests that either quercetin is simply binding to surface GLUT1 or its transport in and out of the cell reaches equilibrium very quickly. If quercetin is transported, the co-incubation of quercetin with other glucose inhibitors should block quercetin uptake. However, we observed that WZB-117, an exofacial binding inhibitor of GLUT1 reduced quercetin interaction, while cytochalasin B, an endofacial binding inhibitor, enhanced quercetin interaction, and BAY-876 had no effect on quercetin interaction. Taken together, these data are more consistent with quercetin simply binding to GLUT1, but not actually being transported into L929 cells via the glucose channel in GLUT1.
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14
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Ceder MM, Lekholm E, Hellsten SV, Perland E, Fredriksson R. The Neuronal and Peripheral Expressed Membrane-Bound UNC93A Respond to Nutrient Availability in Mice. Front Mol Neurosci 2017; 10:351. [PMID: 29163028 PMCID: PMC5671512 DOI: 10.3389/fnmol.2017.00351] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 10/13/2017] [Indexed: 12/31/2022] Open
Abstract
Many transporters such as the solute carriers belonging to the Major facilitator superfamily Pfam clan are orphans in that their tissue and cellular localization as well as substrate profile and function are still unknown. Here we have characterized the putative solute carrier UNC93A. We aimed to investigate the expression profile on both protein and mRNA level of UNC93A in mouse since it has not been clarified. UNC93A staining was found in cortex, hippocampus and cerebellum. It was found to be expressed in many neurons, but not all, with staining located in close proximity to the plasma membrane. Furthermore, we aimed to extend the starvation data available for Unc93a in hypothalamic cell cultures from mouse. We investigated the Unc93a alterations with focus on amino acid deprivation in embryonic cortex cells from mice as well as 24 h starvation in adult male mice and compared it to recently studied putative and known solute carriers. Unc93a expression was found both in the brain and peripheral organs, in low to moderate levels in the adult mice and was affected by amino acid deprivation in embryonic cortex cultures and starvation in in vivo samples. In conclusion, the membrane-bound UNC93A is expressed in both the brain and peripheral tissues and responds to nutrient availability in mice.
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Affiliation(s)
- Mikaela M Ceder
- Molecular Neuropharmacology, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Emilia Lekholm
- Molecular Neuropharmacology, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Sofie V Hellsten
- Molecular Neuropharmacology, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Emelie Perland
- Molecular Neuropharmacology, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | - Robert Fredriksson
- Molecular Neuropharmacology, Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
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15
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Oh CS, Hong JH, Jin SN, Lee WJ, Lee YS, Lee E. Expression of glucose transporters in the developing rat skin. Anat Cell Biol 2017; 50:214-218. [PMID: 29043100 PMCID: PMC5639176 DOI: 10.5115/acb.2017.50.3.214] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 07/10/2017] [Accepted: 07/16/2017] [Indexed: 12/21/2022] Open
Abstract
We found the changed distribution of glucose transporter (GLUT) proteins in the skin during rat development. At 15 days of gestation, GLUT1 and 2 proteins were expressed in the stratum corneum of epidermal cells. In postnatal skin, however, GLUT1 and 2 exhibit different expression patterns. While GLUT1 expression becomes more restricted to the stratum basale with development, GLUT2 was found mainly in stratum spinosum and granulosum, but not being localized in the stratum basale at any stages of perinatal skin development. Considering all these, it can be speculated that each GLUT protein plays its specific role in different epidermal layers and that the glucose used in mammalian skin in utero could be originated from the amniotic fluid during skin development.
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Affiliation(s)
- Chang Seok Oh
- Department of Anatomy and Cell Biology, Seoul National University College of Medicine, Seoul, Korea
| | - Jong Ha Hong
- Department of Anatomy and Cell Biology, Seoul National University College of Medicine, Seoul, Korea
| | - Shun Nu Jin
- Department of Anatomy and Cell Biology, Seoul National University College of Medicine, Seoul, Korea
| | - Wang Jae Lee
- Department of Anatomy and Cell Biology, Seoul National University College of Medicine, Seoul, Korea
| | - Young Soo Lee
- Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Eunju Lee
- Department of Internal Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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16
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Santos GC, Zeidler JD, Pérez-Valencia JA, Sant'Anna-Silva ACB, Da Poian AT, El-Bacha T, Almeida FCL. Metabolomic Analysis Reveals Vitamin D-induced Decrease in Polyol Pathway and Subtle Modulation of Glycolysis in HEK293T Cells. Sci Rep 2017; 7:9510. [PMID: 28842639 PMCID: PMC5573350 DOI: 10.1038/s41598-017-10006-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 08/02/2017] [Indexed: 12/21/2022] Open
Abstract
We combined 1H NMR metabolomics with functional and molecular biochemical assays to describe the metabolic changes elicited by vitamin D in HEK293T, an embryonic proliferative cell line adapted to high-glucose concentrations. Activation of the polyol pathway, was the most important consequence of cell exposure to high glucose concentration, resembling cells exposed to hyperglycemia. Vitamin D induced alterations in HEK293T cells metabolism, including a decrease in sorbitol, glycine, glutamate, guanine. Vitamin D modulated glycolysis by increasing phosphoglycerate mutase and decreasing enolase activities, changing carbon fate without changing glucose consumption, lactate export and Krebs cycle. The decrease in sorbitol intracellular concentration seems to be related to vitamin D regulated redox homeostasis and protection against oxidative stress, and helped maintaining the high proliferative phenotype, supported by the decrease in glycine and guanine and orotate concentration and increase in choline and phosphocholine concentration. The decrease in orotate and guanine indicated an increased biosynthesis of purine and pyrimidines. Vitamin D elicited metabolic alteration without changing cellular proliferation and mitochondrial respiration, but reclaiming reductive power. Our study may contribute to the understanding of the metabolic mechanism of vitamin D upon exposure to hyperglycemia, suggesting a role of protection against oxidative stress.
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Affiliation(s)
- G C Santos
- Federal University of Rio de Janeiro, Institute of Medical Biochemistry, Leopoldo de Meis, Brazil. .,Federal University of Rio de Janeiro, National Center for Structural Biology and Bioimaging (CENABIO)/National Center for Nuclear Magnetic Resonance (CNRMN), Rio de Janeiro, Brazil.
| | - J D Zeidler
- Federal University of Rio de Janeiro, Institute of Medical Biochemistry, Leopoldo de Meis, Brazil
| | - J A Pérez-Valencia
- Federal University of Rio de Janeiro, Institute of Medical Biochemistry, Leopoldo de Meis, Brazil
| | - A C B Sant'Anna-Silva
- Federal University of Rio de Janeiro, Institute of Medical Biochemistry, Leopoldo de Meis, Brazil
| | - A T Da Poian
- Federal University of Rio de Janeiro, Institute of Medical Biochemistry, Leopoldo de Meis, Brazil
| | - T El-Bacha
- Federal University of Rio de Janeiro, National Center for Structural Biology and Bioimaging (CENABIO)/National Center for Nuclear Magnetic Resonance (CNRMN), Rio de Janeiro, Brazil.,Federal University of Rio de Janeiro, Institute of Nutrition Josué de Castro, Rio de Janeiro, Brazil
| | - F C L Almeida
- Federal University of Rio de Janeiro, Institute of Medical Biochemistry, Leopoldo de Meis, Brazil. .,Federal University of Rio de Janeiro, National Center for Structural Biology and Bioimaging (CENABIO)/National Center for Nuclear Magnetic Resonance (CNRMN), Rio de Janeiro, Brazil.
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17
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Seleit I, Bakry OA, Al-Sharaky DR, Ragab RAA, Al-Shiemy SA. Evaluation of Hypoxia Inducible Factor-1α and Glucose Transporter-1 Expression in Non Melanoma Skin Cancer: An Immunohistochemical Study. J Clin Diagn Res 2017; 11:EC09-EC16. [PMID: 28764171 DOI: 10.7860/jcdr/2017/25077.10022] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 01/13/2017] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Hypoxia Inducible Factor-1 (HIF-1) is a mediator enabling cell adaptation to hypoxia. It plays its role mainly through transcription of many target genes including Glucose Transporter-1 (GLUT-1) gene. AIM The present work aimed at evaluating the pattern and distribution of HIF-1α and GLUT-1 in each case and control. MATERIALS AND METHODS A case-control and retrospective study was conducted on archival blocks diagnosed from pathology department as, Basal Cell Carcinoma (BCC, 20 cases), cutaneous Squamous Cell Carcinoma (SCC, 20 cases) and 20 normal site-matched skin biopsies from age and gender-matched healthy subjects as a control. Evaluation of both HIF-1α and GLUT1 expression using standard immunohistochemical techniques was performed on cut sections from selected paraffin embedded blocks. RESULTS HIF-1α was expressed in 90%, 35% and 100% of normal skin, BCC and SCC tumour islands respectively. It was up regulated in both BCC and SCC compared with normal skin (p= 0.001, p<0.001 respectively). GLUT-1 was expressed in 100%, 70% and 100% of normal skin, BCC and SCC tumour islands respectively. It was down regulated in Non Melanoma Skin Cancer (NMSC) cases compared with normal skin (p=0.004). HIF-1α and GLUT-1 localization in tumour nests was central, peripheral or central and peripheral. Both HIF-1α and GLUT-1 showed variable expression in stroma, adnexa and inflammatory cells. No significant correlation was found between Histo (H) score or expression percentage values of HIF-1α and those of GLUT-1 in tumour islands or in overlying epidermis either in BCC or SCC. CONCLUSION HIF-1α may have a role in NMSC pathogenesis through adaptation to hypoxia which results from excessive proliferation. GLUT-1 down regulation in NMSC may be explained by its consumption by proliferating tumour cells. The expression of HIF-1α and GLUT-1 in normal epidermis, stromal and adnexal structures needs further research.
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Affiliation(s)
- Iman Seleit
- Professor, Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine Menoufia University, Egypt
| | - Ola Ahmed Bakry
- Assistant Professor, Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine, Menoufia University, Egypt
| | - Dalia Rifaat Al-Sharaky
- Assistant Professor, Department of Pathology, Faculty of Medicine, Menoufia University, Egypt
| | - Rania Abdel Aziz Ragab
- Resident, Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine, Menoufia University, Egypt
| | - Shimaa Ahmed Al-Shiemy
- Resident, Department of Dermatology, Andrology and S.T.Ds, Faculty of Medicine, Menoufia University, Egypt
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18
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Gunnink LK, Busscher BM, Wodarek JA, Rosette KA, Strohbehn LE, Looyenga BD, Louters LL. Caffeine inhibition of GLUT1 is dependent on the activation state of the transporter. Biochimie 2017; 137:99-105. [PMID: 28322926 DOI: 10.1016/j.biochi.2017.03.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Accepted: 03/15/2017] [Indexed: 10/19/2022]
Abstract
Caffeine has been shown to be a robust uncompetitive inhibitor of glucose uptake in erythrocytes. It preferentially binds to the nucleotide-binding site on GLUT1 in its tetrameric form and mimics the inhibitory action of ATP. Here we demonstrate that caffeine is also a dose-dependent, uncompetitive inhibitor of 2-deoxyglucose (2DG) uptake in L929 fibroblasts. The inhibitory effect on 2DG uptake in these cells was reversible with a rapid onset and was additive to the competitive inhibitory effects of glucose itself, confirming that caffeine does not interfere with glucose binding. We also report for the first time that caffeine inhibition was additive to inhibition by curcumin, suggesting distinct binding sites for curcumin and caffeine. In contrast, caffeine inhibition was not additive to that of cytochalasin B, consistent with previous data that reported that these two inhibitors have overlapping binding sites. More importantly, we show that the magnitude of maximal caffeine inhibition in L929 cells is much lower than in erythrocytes (35% compared to 90%). Two epithelial cell lines, HCLE and HK2, have both higher concentrations of GLUT1 and increased basal 2DG uptake (3-4 fold) compared to L929 cells, and subsequently display greater maximal inhibition by caffeine (66-70%). Interestingly, activation of 2DG uptake (3-fold) in L929 cells by glucose deprivation shifted the responsiveness of these cells to caffeine inhibition (35%-70%) without a change in total GLUT1 concentration. These data indicate that the inhibition of caffeine is dependent on the activity state of GLUT1, not merely on the concentration.
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Affiliation(s)
- Leesha K Gunnink
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | - Brianna M Busscher
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | - Jeremy A Wodarek
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | - Kylee A Rosette
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | - Lauren E Strohbehn
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | - Brendan D Looyenga
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | - Larry L Louters
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA.
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19
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Xie M, Ye H, Wang H, Charpin-El Hamri G, Lormeau C, Saxena P, Stelling J, Fussenegger M. -cell-mimetic designer cells provide closed-loop glycemic control. Science 2016; 354:1296-1301. [DOI: 10.1126/science.aaf4006] [Citation(s) in RCA: 140] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 11/10/2016] [Indexed: 12/12/2022]
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20
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Bhute VJ, Ma Y, Bao X, Palecek SP. The Poly (ADP-Ribose) Polymerase Inhibitor Veliparib and Radiation Cause Significant Cell Line Dependent Metabolic Changes in Breast Cancer Cells. Sci Rep 2016; 6:36061. [PMID: 27811964 PMCID: PMC5095763 DOI: 10.1038/srep36061] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/04/2016] [Indexed: 12/22/2022] Open
Abstract
Breast tumors are characterized into subtypes based on their surface marker expression, which affects their prognosis and treatment. Poly (ADP-ribose) polymerase (PARP) inhibitors have shown promising results in clinical trials, both as single agents and in combination with other chemotherapeutics, in several subtypes of breast cancer patients. Here, we used NMR-based metabolomics to probe cell line-specific effects of the PARP inhibitor Veliparib and radiation on metabolism in three breast cancer cell lines. Our data reveal several cell line-independent metabolic changes upon PARP inhibition. Pathway enrichment and topology analysis identified that nitrogen metabolism, glycine, serine and threonine metabolism, aminoacyl-tRNA biosynthesis and taurine and hypotaurine metabolism were enriched after PARP inhibition in all three breast cancer cell lines. Many metabolic changes due to radiation and PARP inhibition were cell line-dependent, highlighting the need to understand how these treatments affect cancer cell response via changes in metabolism. Finally, both PARP inhibition and radiation induced a similar metabolic responses in BRCA-mutant HCC1937 cells, but not in MCF7 and MDAMB231 cells, suggesting that radiation and PARP inhibition share similar interactions with metabolic pathways in BRCA mutant cells. Our study emphasizes the importance of differences in metabolic responses to cancer treatments in different subtypes of cancers.
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Affiliation(s)
- Vijesh J Bhute
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Yan Ma
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Xiaoping Bao
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sean P Palecek
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
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21
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Hinger D, Gräfe S, Navarro F, Spingler B, Pandiarajan D, Walt H, Couffin AC, Maake C. Lipid nanoemulsions and liposomes improve photodynamic treatment efficacy and tolerance in CAL-33 tumor bearing nude mice. J Nanobiotechnology 2016; 14:71. [PMID: 27716314 PMCID: PMC5048629 DOI: 10.1186/s12951-016-0223-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 09/27/2016] [Indexed: 11/15/2022] Open
Abstract
Background Photodynamic therapy (PDT) as promising alternative to conventional cancer treatments works by irradiation of a photosensitizer (PS) with light, which creates reactive oxygen species and singlet oxygen (1O2), that damage the tumor. However, a routine use is hindered by the PS’s poor water solubility and extended cutaneous photosensitivity of patients after treatment. In our study we sought to overcome these limitations by encapsulation of the PS m-tetrahydroxyphenylchlorin (mTHPC) into a biocompatible nanoemulsion (Lipidots). Results In CAL-33 tumor bearing nude mice we compared the Lipidots to the existing liposomal mTHPC nanoformulation Foslip and the approved mTHPC formulation Foscan. We established biodistribution profiles via fluorescence measurements in vivo and high performance liquid chromatography (HPLC) analysis. All formulations accumulated in the tumors and we could determine the optimum treatment time point for each substance (8 h for mTHPC, 24 h for Foslip and 72 h for the Lipidots). We used two different light doses (10 and 20 J/cm2) and evaluated immediate PDT effects 48 h after treatment and long term effects 14 days later. We also analyzed tumors by histological analysis and performing reverse transcription real-time PCR with RNA extracts. Concerning tumor destruction Foslip was superior to Lipidots and Foscan while with regard to tolerance and side effects Lipidots were giving the best results. Conclusions We could demonstrate in our study that nanoformulations are superior to the free PS mTHPC. The development of a potent nanoformulation is of major importance because the free PS is related to several issues such as poor bioavailability, solubility and increased photosensibility of patients. We could show in this study that Foslip is very potent in destroying the tumors itself. However, because the Lipidots' biocompatibility is outstanding and superior to the liposomes we plan to carry out further investigations and protocol optimization. Both nanoformulations show great potential to revolutionize PDT in the future. Electronic supplementary material The online version of this article (doi:10.1186/s12951-016-0223-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Doris Hinger
- Institute of Anatomy, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland.
| | - Susanna Gräfe
- Biolitec Research GmbH, Otto-Schott-Str. 15, 07745, Jena, Germany
| | - Fabrice Navarro
- CEA, LETI, MINATEC Campus, Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), Technologies for Biology and Healthcare Division, 38054, Grenoble, France.,Université Grenoble Alpes, Grenoble, 38000, France
| | - Bernhard Spingler
- Department of Inorganic Chemistry, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland
| | - Devaraj Pandiarajan
- Department of Inorganic Chemistry, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland
| | - Heinrich Walt
- Department of Cranio-Maxillofacial Surgery, University Hospital Zurich, Frauenklinikstrasse 24, Zurich, 8091, Switzerland
| | - Anne-Claude Couffin
- CEA, LETI, MINATEC Campus, Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), Technologies for Biology and Healthcare Division, 38054, Grenoble, France.,Université Grenoble Alpes, Grenoble, 38000, France
| | - Caroline Maake
- Institute of Anatomy, University of Zurich, Winterthurerstrasse 190, Zurich, 8057, Switzerland
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22
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Carrig S, Bijjiga E, Wopat MJ, Martino AT. Insulin Therapy Improves Adeno-Associated Virus Transduction of Liver and Skeletal Muscle in Mice and Cultured Cells. Hum Gene Ther 2016; 27:892-905. [PMID: 27358030 DOI: 10.1089/hum.2016.073] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Adeno-associated virus (AAV) gene transfer is a promising treatment for genetic abnormalities. Optimal AAV vectors are showing success in clinical trials. Gene transfer to skeletal muscle and liver is being explored as a potential therapy for some conditions, that is, α1-antitrypsin (AAT) disorder and hemophilia B. Exploring approaches that enhance transduction of liver and skeletal muscle, using these vectors, is beneficial for gene therapy. Regulating hormones as an approach to improve AAV transduction is largely unexplored. In this study we tested whether insulin therapy improves liver and skeletal muscle gene transfer. In vitro studies demonstrated that the temporary coadministration (2, 8, and 24 hr) of insulin significantly improves AAV2-CMV-LacZ transduction of cultured liver cells and differentiated myofibers, but not of lung cells. In addition, there was a dose response related to this improved transduction. Interestingly, when insulin was not coadministered with the virus but given 24 hr afterward, there was no increase in the transgene product. Insulin receptor gene (INSR) expression levels were increased 5- to 13-fold in cultured liver cells and differentiated myofibers when compared with lung cells. Similar INSR gene expression profiles occurred in mouse tissues. Insulin therapy was performed in mice, using a subcutaneously implanted insulin pellet or a high-carbohydrate diet. Insulin treatment began just before intramuscular delivery of AAV1-CMV-schFIX or liver-directed delivery of AAV8-CMV-schFIX and continued for 28 days. Both insulin augmentation therapies improved skeletal muscle- and liver-directed gene transduction in mice as seen by a 3.0- to 4.5-fold increase in human factor IX (hFIX) levels. The improvement was observed even after the insulin therapy ended. Monitoring insulin showed that insulin levels increased during the brief period of rAAV delivery and during the entire insulin augmentation period (28 days). This study demonstrates that AAV transduction of liver or skeletal muscle can be improved by insulin therapy.
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Affiliation(s)
- Sean Carrig
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University , Queens, New York
| | - Enoch Bijjiga
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University , Queens, New York
| | - Mitchell J Wopat
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University , Queens, New York
| | - Ashley T Martino
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University , Queens, New York
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23
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Xu J, Begley P, Church SJ, Patassini S, McHarg S, Kureishy N, Hollywood KA, Waldvogel HJ, Liu H, Zhang S, Lin W, Herholz K, Turner C, Synek BJ, Curtis MA, Rivers-Auty J, Lawrence CB, Kellett KAB, Hooper NM, Vardy ERLC, Wu D, Unwin RD, Faull RLM, Dowsey AW, Cooper GJS. Elevation of brain glucose and polyol-pathway intermediates with accompanying brain-copper deficiency in patients with Alzheimer's disease: metabolic basis for dementia. Sci Rep 2016; 6:27524. [PMID: 27276998 DOI: 10.1038/srep27524] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 05/19/2016] [Indexed: 12/25/2022] Open
Abstract
Impairment of brain-glucose uptake and brain-copper regulation occurs in Alzheimer's disease (AD). Here we sought to further elucidate the processes that cause neurodegeneration in AD by measuring levels of metabolites and metals in brain regions that undergo different degrees of damage. We employed mass spectrometry (MS) to measure metabolites and metals in seven post-mortem brain regions of nine AD patients and nine controls, and plasma-glucose and plasma-copper levels in an ante-mortem case-control study. Glucose, sorbitol and fructose were markedly elevated in all AD brain regions, whereas copper was correspondingly deficient throughout (all P < 0.0001). In the ante-mortem case-control study, by contrast, plasma-glucose and plasma-copper levels did not differ between patients and controls. There were pervasive defects in regulation of glucose and copper in AD brain but no evidence for corresponding systemic abnormalities in plasma. Elevation of brain glucose and deficient brain copper potentially contribute to the pathogenesis of neurodegeneration in AD.
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Affiliation(s)
- Jingshu Xu
- School of Biological Sciences, and Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Paul Begley
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Stephanie J Church
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Stefano Patassini
- School of Biological Sciences, and Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Selina McHarg
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Nina Kureishy
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Katherine A Hollywood
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Henry J Waldvogel
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Hong Liu
- School of Biological Sciences, and Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, New Zealand
| | - Shaoping Zhang
- School of Biological Sciences, and Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, New Zealand
| | - Wanchang Lin
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Karl Herholz
- Institute of Brain, Behaviour and Mental Health, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Clinton Turner
- Anatomical Pathology, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Beth J Synek
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Anatomical Pathology, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Maurice A Curtis
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Jack Rivers-Auty
- Institute of Brain, Behaviour and Mental Health, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Catherine B Lawrence
- Institute of Brain, Behaviour and Mental Health, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Katherine A B Kellett
- Institute of Brain, Behaviour and Mental Health, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Nigel M Hooper
- Institute of Brain, Behaviour and Mental Health, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | | | - Donghai Wu
- Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China
| | - Richard D Unwin
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Richard L M Faull
- Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Andrew W Dowsey
- Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
| | - Garth J S Cooper
- School of Biological Sciences, and Maurice Wilkins Centre for Molecular Biodiscovery, Faculty of Science, University of Auckland, New Zealand.,Centre for Brain Research, Faculty of Medical and Health Sciences, University of Auckland, New Zealand.,Centre for Advanced Discovery and Experimental Therapeutics (CADET), Central Manchester University Hospitals NHS Foundation Trust, and Institute of Human Development, Faculty of Medical and Human Sciences, University of Manchester, United Kingdom
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Li S, Wang J, Wei Y, Liu Y, Ding X, Dong B, Xu Y, Wang Y. Critical role of TRPC6 in maintaining the stability of HIF-1α in glioma cells under hypoxia. J Cell Sci 2015; 128:3317-29. [PMID: 26187851 DOI: 10.1242/jcs.173161] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 07/07/2015] [Indexed: 12/19/2022] Open
Abstract
Hypoxia-inducible factor-1 (HIF-1) is a key transcriptional factor responsible for the expression of a broad range of genes that facilitate acclimatization to hypoxia. Its stability is predominantly controlled by rapid hydroxylation of two prolines on its α subunit. However, how the rapid hydroxylation of HIF-1α is regulated is not fully understood. Here, we report that transient receptor potential canonical (TRPC) 6 channels control hydroxylation and stability of HIF-1α in human glioma cells under hypoxia. TRPC6 was rapidly activated by IGF-1R-PLCγ-IP3R pathway in hypoxia. Inhibition of TRPC6 enhanced the levels of α-ketoglutarate (α-KG) and promoted hydroxylation of HIF-1α to suppress HIF-1α accumulation without affecting its transcription or translation. Dimethyloxalylglycine N-(methoxyoxoacetyl)-glycine methyl ester (DMOG), an analog of α-KG, reversed the inhibition of HIF-1α accumulation. Moreover, TRPC6 regulated GLUT1 expression depending on HIF-1α accumulation to affect glucose uptake in hypoxia. Our results suggest that TRPC6 regulates metabolism to affect HIF-1α stability and consequent glucose metabolism in human glioma cells under hypoxia.
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Affiliation(s)
- Shanshan Li
- Laboratory of Neural Signal Transduction, Institute of Neuroscience, Shanghai Institutes of Biological Sciences, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jinkui Wang
- Department of Neurosurgery, 1st Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Yi Wei
- Department of Neurosurgery, 1st Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Yongjian Liu
- Department of Neurosurgery, 1st Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Xia Ding
- Laboratory of Neural Signal Transduction, Institute of Neuroscience, Shanghai Institutes of Biological Sciences, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai 200031, China
| | - Bin Dong
- Department of Neurosurgery, 1st Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Yinghui Xu
- Department of Neurosurgery, 1st Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Yizheng Wang
- Laboratory of Neural Signal Transduction, Institute of Neuroscience, Shanghai Institutes of Biological Sciences, State Key Laboratory of Neuroscience, Chinese Academy of Sciences, Shanghai 200031, China
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Sirover WD, Liu Y, Logan A, Hunter K, Benz RL, Prasad D, Avila J, Venkatchalam T, Weisberg LS, Handelman GJ. Plasma ascorbic acid concentrations in prevalent patients with end-stage renal disease on hemodialysis. J Ren Nutr 2014; 25:292-300. [PMID: 25455040 DOI: 10.1053/j.jrn.2014.09.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 09/18/2014] [Accepted: 09/24/2014] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVE To determine the prevalence of vitamin C (ascorbic acid [AA]) deficiency in patients with end-stage renal disease, the effect of supplemental AA on plasma AA concentrations, and the extrinsic and intrinsic factors that affect plasma AA concentrations in this patient population. DESIGN In study 1, we compared the effect of hemodialysis (HD) on plasma AA concentrations between patients with low and high pre-HD AA concentrations. In study 2, we analyzed kinetic and nonkinetic factors for their association with increased plasma AA concentrations in patients on maintenance HD. Study 1 was performed in a single outpatient HD clinic in Cherry Hill, New Jersey. Study 2 was performed in 4 outpatient HD clinics in Southern New Jersey. SUBJECTS AND INTERVENTION In study 1, we collected plasma samples from 8 adult patients on maintenance HD at various time points around their HD treatment and assayed them for AA concentration. In study 2, we enrolled 203 adult patients and measured pre-HD plasma AA concentrations. We ascertained supplemental AA use and assessed dietary AA intake. MAIN OUTCOME MEASURE In study 1, plasma AA concentrations were compared during the intradialytic and interdialytic period. In study 2, pre-HD plasma AA concentrations were correlated with supplement use and demographic factors. RESULTS Study 1 showed that over the course of a single HD treatment, the plasma AA concentration decreased by a mean (±standard deviation) of 60% (±6.6). In study 2, the median pre-HD plasma AA concentration was 15.7 μM (interquartile range, 8.7-66.8) in patients who did not take a supplement and 50.6 μM (interquartile range, 25.1-88.8) in patients who did take a supplement (P < .001). Supplement use, increasing age, and diabetes mellitus were associated with a pre-HD plasma AA concentration ≥30 μM. CONCLUSION HD depletes plasma AA concentrations, and AA supplementation allows patients to achieve higher plasma AA concentrations.
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Affiliation(s)
- William D Sirover
- Division of Nephrology, Department of Medicine, Cooper Medical School of Rowan University, Camden, New Jersey.
| | - Yuguan Liu
- Clinical Laboratory and Nutritional Sciences, University of Massachusetts, Lowell, Massachusetts
| | | | - Krystal Hunter
- Department of Biostatistics, Cooper Research Institute, Camden, New Jersey
| | - Robert L Benz
- Lankenau Medical Center and Lankenau Institute for Medical Research, Wynnewood, Pennsylvania
| | - Deepali Prasad
- Department of Medicine, Cooper University Hospital, Camden, New Jersey
| | - Jose Avila
- Department of Medicine, Cooper University Hospital, Camden, New Jersey
| | | | - Lawrence S Weisberg
- Division of Nephrology, Department of Medicine, Cooper Medical School of Rowan University, Camden, New Jersey
| | - Garry J Handelman
- Clinical Laboratory and Nutritional Sciences, University of Massachusetts, Lowell, Massachusetts
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Sawangmake C, Pavasant P, Chansiripornchai P, Osathanon T. High Glucose Condition Suppresses Neurosphere Formation by Human Periodontal Ligament-Derived Mesenchymal Stem Cells. J Cell Biochem 2014; 115:928-39. [DOI: 10.1002/jcb.24735] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 12/04/2013] [Indexed: 12/11/2022]
Affiliation(s)
- Chenphop Sawangmake
- Department of Pharmacology; Faculty of Veterinary Science; Chulalongkorn University; Bangkok 10330 Thailand
- Research Unit of Mineralized Tissue; Faculty of Dentistry; Chulalongkorn University; Bangkok 10330 Thailand
- Graduate Program in Veterinary Bioscience; Faculty of Veterinary Science; Chulalongkorn University; Bangkok 10330 Thailand
| | - Prasit Pavasant
- Research Unit of Mineralized Tissue; Faculty of Dentistry; Chulalongkorn University; Bangkok 10330 Thailand
- Department of Anatomy; Faculty of Dentistry; Chulalongkorn University; Bangkok 10330 Thailand
| | - Piyarat Chansiripornchai
- Department of Pharmacology; Faculty of Veterinary Science; Chulalongkorn University; Bangkok 10330 Thailand
| | - Thanaphum Osathanon
- Department of Anatomy; Faculty of Dentistry; Chulalongkorn University; Bangkok 10330 Thailand
- DRU in Genetic and Anatomical Analyses of Craniofacial Structure; Faculty of Dentistry; Chulalongkorn University; Bangkok 10330 Thailand
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Lee JJ, Huang J, England CG, McNally LR, Frieboes HB. Predictive modeling of in vivo response to gemcitabine in pancreatic cancer. PLoS Comput Biol 2013; 9:e1003231. [PMID: 24068909 PMCID: PMC3777914 DOI: 10.1371/journal.pcbi.1003231] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 08/03/2013] [Indexed: 01/03/2023] Open
Abstract
A clear contradiction exists between cytotoxic in-vitro studies demonstrating effectiveness of Gemcitabine to curtail pancreatic cancer and in-vivo studies failing to show Gemcitabine as an effective treatment. The outcome of chemotherapy in metastatic stages, where surgery is no longer viable, shows a 5-year survival <5%. It is apparent that in-vitro experiments, no matter how well designed, may fail to adequately represent the complex in-vivo microenvironmental and phenotypic characteristics of the cancer, including cell proliferation and apoptosis. We evaluate in-vitro cytotoxic data as an indicator of in-vivo treatment success using a mathematical model of tumor growth based on a dimensionless formulation describing tumor biology. Inputs to the model are obtained under optimal drug exposure conditions in-vitro. The model incorporates heterogeneous cell proliferation and death caused by spatial diffusion gradients of oxygen/nutrients due to inefficient vascularization and abundant stroma, and thus is able to simulate the effect of the microenvironment as a barrier to effective nutrient and drug delivery. Analysis of the mathematical model indicates the pancreatic tumors to be mostly resistant to Gemcitabine treatment in-vivo. The model results are confirmed with experiments in live mice, which indicate uninhibited tumor proliferation and metastasis with Gemcitabine treatment. By extracting mathematical model parameter values for proliferation and death from monolayer in-vitro cytotoxicity experiments with pancreatic cancer cells, and simulating the effects of spatial diffusion, we use the model to predict the drug response in-vivo, beyond what would have been expected from sole consideration of the cancer intrinsic resistance. We conclude that this integrated experimental/computational approach may enhance understanding of pancreatic cancer behavior and its response to various chemotherapies, and, further, that such an approach could predict resistance based on pharmacokinetic measurements with the goal to maximize effective treatment strategies.
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Affiliation(s)
- James J. Lee
- School of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Justin Huang
- School of Medicine, University of Louisville, Louisville, Kentucky, United States of America
| | - Christopher G. England
- Department of Pharmacology/Toxicology, University of Louisville, Louisville, Kentucky, United States of America
| | - Lacey R. McNally
- School of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail: (LRM); (HBF)
| | - Hermann B. Frieboes
- James Graham Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
- Department of Bioengineering, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail: (LRM); (HBF)
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Narayanan K, Lin AWH, Zheng Y, Erathodiyil N, Wan ACA, Ying JY. Glucosamine-conjugated nanoparticles for the separation of insulin-secreting beta cells. Adv Healthc Mater 2013; 2:1198-203. [PMID: 23471896 DOI: 10.1002/adhm.201200479] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 01/07/2013] [Indexed: 01/06/2023]
Abstract
A small molecule, glucosamine, is used as targeting moiety for insulin-secreting beta cell separation in artificial cell mixtures and tissue samples. The specificity of glucosamine allows it to be used in cell sorting applications. In addition, a thrombin-specific cleavable peptide was used as an intermediary to release nanoparticles from cell surfaces to facilitate cell attachment and proliferation.
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Affiliation(s)
- Karthikeyan Narayanan
- Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, The Nanos, Singapore 138669 Singapore
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Lertanekawattana S, Wichatrong T, Chaisari K, Uchikawa R, Arizono N. Immunological characteristics of patients infected with common intestinal helminths: results of a study based on reverse-transcriptase PCR. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2013; 99:71-80. [PMID: 15701258 DOI: 10.1179/136485905x19892] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
To determine whether common helminth infections could modify the intestinal immunopathological status of the host, the expression in the human duodenal mucosa of cytokines, eosinophil- and mast-cell-specific molecules and monosaccharide transporters of the glucose-transporter (GLUT) family was explored. The 31 subjects were all patients at the gastro-intestinal disease unit of Nongkhai Hospital, Thailand. Four of the 10 patients who presented with eosinophilia (> or = 6.0% of their leucocytes were eosinophils), and five of the other 21 patients, had intestinal infections with helminths when they presented or within the previous 3 months. Studies based on semi-quantitative, reverse-transcriptase PCR revealed that the interleukin-5/interferon-gamma ratio was significantly higher in the noneosinophilic, helminth-infected patients than in the non-eosinophilic, uninfected patients, whereas the IgE receptor type I (Fc epsilon RI)/mast-cell tryptase ratio was significantly higher in the eosinophilic, helminth-infected patients than in the eosinophilic, uninfected patients. Expression of Charcot-Leyden-crystal protein, GLUT-1 and GLUT-5, however, showed no significant inter-group differences. Principal-components analysis of the data on eosinophils, interleukin-5, interferon-gamma, Fc epsilon RI and mast-cell tryptase revealed that one principal component could discriminate the patients who had helminth infection from the non-eosinophilic, uninfected patients, but not from the eosinophilic, uninfected patients. These results indicate that, whatever the intestinal pathology, patients infected with common intestinal helminths tend to develop a mucosal immunological response of the Th2 type.
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Zhang C, Niu W, Wang Z, Wang X, Xia G. The effect of gonadotropin on glucose transport and apoptosis in rat ovary. PLoS One 2012; 7:e42406. [PMID: 22870326 PMCID: PMC3411621 DOI: 10.1371/journal.pone.0042406] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 07/04/2012] [Indexed: 12/03/2022] Open
Abstract
Although the effects of Gonadotropin on ovarian physiology have been known for many decades, its action on glucose uptake in the rat ovary remained poorly understood. Evidence also suggests that glucose uptake is mediated by a number of glucose transporter proteins (Glut). Therefore, we examined the rat ovary for the presence of Glut1–4 and blood glucose level after eCG (equine chorionic gonadotropin) and anti-eCG antiserum treatment. All of the glucose transports were present in the ovarian oocyte, granulosa cells and theca cells in different stage follicles. The expression of Glut in ovary was up-regulated by eCG, however, anti-eCG antiserum reversed eCG action. Western blot analysis also demonstrated the content of Glut1 was higher in eCG treatment group compared with anti-eCG antiserum and control group. The same tendency was shown in other glut isoforms. Moreover, there were no significant difference between the anti-eCG antiserum and control group. In additional, the level of serum glucose in eCG treatment group was significantly higher than others, which is similar with glut expression pattern. High glucose level in blood is correlated with increased expression of glucose transporter proteins in rat ovary. Meanwhile, anti-eCG antiserum increased granulosa cell apoptosis in antral follicle compared with those in eCG group. Our observations provide potential explanation for the effects of Glut on follicular development in rat ovary and a role for eCG in the regulation of ovarian glucose uptake.
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Affiliation(s)
- Cheng Zhang
- College of Life Science, Capital Normal University, Beijing, People's Republic of China
| | - Wanbao Niu
- State Key Laboratory for Agro-Biotechnology, College of Biological Science, China Agricultural University, Beijing, People's Republic of China
| | - Zhengpin Wang
- State Key Laboratory for Agro-Biotechnology, College of Biological Science, China Agricultural University, Beijing, People's Republic of China
| | - Xiaoxia Wang
- College of Life Science, Capital Normal University, Beijing, People's Republic of China
- * E-mail: (XW); (GX)
| | - Guoliang Xia
- State Key Laboratory for Agro-Biotechnology, College of Biological Science, China Agricultural University, Beijing, People's Republic of China
- * E-mail: (XW); (GX)
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Keats EC, Khan ZA. Vascular stem cells in diabetic complications: evidence for a role in the pathogenesis and the therapeutic promise. Cardiovasc Diabetol 2012; 11:37. [PMID: 22524626 PMCID: PMC3476432 DOI: 10.1186/1475-2840-11-37] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 04/23/2012] [Indexed: 12/25/2022] Open
Abstract
Long standing diabetes leads to structural and functional alterations in both the micro- and the macro-vasculature. Vascular endothelial cells (ECs) are the primary target of the hyperglycemia-induced adverse effects. Vascular stem cells that give rise to endothelial progenitor cells (EPCs) and mesenchymal progenitor cells (MPCs) represent an attractive target for cell therapy for diabetic patients. A number of studies have reported EPC dysfunction as a novel participant in the culmination of the diabetic complications. The controversy behind the identity of EPCs and the similarity between these progenitor cells to hematopoietic cells has led to conflicting results. MPCs, on the other hand, have not been examined for a potential role in the pathogenesis of the complications. These multipotent cells, however, do show a therapeutic role. In this article, we summarize the vascular changes that occur in diabetic complications highlighting some of the common features, the key findings that illustrate an important role of vascular stem cells (VSCs) in the pathogenesis of chronic diabetic complications, and provide mechanisms by which these cells can be used for therapy.
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MESH Headings
- Animals
- Blood Glucose/metabolism
- Diabetic Angiopathies/blood
- Diabetic Angiopathies/pathology
- Diabetic Angiopathies/physiopathology
- Diabetic Angiopathies/surgery
- Endothelial Cells/metabolism
- Endothelial Cells/pathology
- Endothelial Cells/transplantation
- Endothelium, Vascular/metabolism
- Endothelium, Vascular/pathology
- Endothelium, Vascular/physiopathology
- Humans
- Mesenchymal Stem Cell Transplantation
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Muscle, Smooth, Vascular/physiopathology
- Neovascularization, Physiologic
- Regeneration
- Treatment Outcome
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Affiliation(s)
- Emily C Keats
- Department of Pathology, University of Western Ontario, London, ON, Canada
| | - Zia A Khan
- Department of Pathology, University of Western Ontario, London, ON, Canada
- Metabolism and Diabetes Program, Lawson Health Research Institute, London, ON, Canada
- 4011 Dental Sciences Building, 1151 Richmond Street, London, ON, N6A 5C1, Canada
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Haberkorn U, Markert A, Mier W, Askoxylakis V, Altmann A. Molecular imaging of tumor metabolism and apoptosis. Oncogene 2011; 30:4141-51. [DOI: 10.1038/onc.2011.169] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Busk M, Toustrup K, Sørensen BS, Alsner J, Horsman MR, Jakobsen S, Overgaard J. In vivo identification and specificity assessment of mRNA markers of hypoxia in human and mouse tumors. BMC Cancer 2011; 11:63. [PMID: 21306648 PMCID: PMC3042974 DOI: 10.1186/1471-2407-11-63] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 02/09/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Tumor hypoxia is linked to poor prognosis, but identification and quantification of tissue hypoxia remains a challenge. The hypoxia-specificity of HIF-1α target genes in vivo has been questioned due to the confounding influence of other microenvironmental abnormalities known to affect gene expression (e.g., low pH). Here we describe a new technique that by exploiting intratumoral oxygenation heterogeneity allows us to identify and objectively rank the most robust mRNA hypoxia biomarkers. METHODS Mice carrying human (FaDudd) or murine (SCCVII) tumors were injected with the PET hypoxia tracer FAZA. Four hours post-injection tumors were removed, frozen, and crushed into milligram-sized fragments, which were transferred individually to pre-weighed tubes containing RNAlater and then weighed. For each fragment radioactivity per tissue mass and expression patterns of selected mRNA biomarkers were analyzed and compared. RESULTS In both tumour models, fragmentation into pieces weighing 10 to 60 mg resulted in tissue fragments with highly variable relative content of hypoxic cells as evidenced by an up to 13-fold variation in FAZA radioactivity per mass of tissue. Linear regression analysis comparing FAZA retention with patterns of gene expression in individual tissue fragments revealed that CA9, GLUT1 and LOX mRNA levels were equally and strongly correlated to hypoxic extent in FaDudd. The same link between hypoxia and gene expression profile was observed for CA9 and GLUT1, but not LOX, in SCCVII tumors. Apparent in vivo hypoxia-specificity for other putative molecular markers of tissue hypoxia was considerably weaker. CONCLUSIONS The portrayed technique allows multiple pairwise measurements of mRNA transcript levels and extent of hypoxia in individual tumors at a smallest possible volumetric scale which (by limiting averaging effects inherent to whole-tumor analysis) strengthen the conclusiveness on true hypoxia-specificity of candidate genes while limiting the required number of tumors. Among tested genes, our study identified CA9, GLUT1 and possibly LOX as highly specific biomarkers of tumor hypoxia in vivo.
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Affiliation(s)
- Morten Busk
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark.
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Plaisier C, Cok A, Scott J, Opejin A, Bushhouse KT, Salie MJ, Louters LL. Effects of cinnamaldehyde on the glucose transport activity of GLUT1. Biochimie 2010; 93:339-44. [PMID: 20955755 DOI: 10.1016/j.biochi.2010.10.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Accepted: 10/11/2010] [Indexed: 01/09/2023]
Abstract
There is accumulating evidence that cinnamon extracts contain components that enhance insulin action. However, little is know about the effects of cinnamon on non-insulin stimulated glucose uptake. Therefore, the effects of cinnamaldehyde on the glucose transport activity of GLUT1 in L929 fibroblast cells were examined under both basal conditions and conditions where glucose uptake is activated by glucose deprivation. The data reveal that cinnamaldehyde has a dual action on the glucose transport activity of GLUT1. Under basal conditions it stimulates glucose uptake and reaches a 3.5 fold maximum stimulation at 2.0mM. However, cinnamaldehyde also inhibits the activation of glucose uptake by glucose deprivation in a dose dependent manner. Experiments with cinnamaldehyde analogs reveal that these activities are dependent on the α,β-unsaturated aldehyde structural motif in cinnamaldehyde. The inhibitory, but not the stimulatory activity of cinnamaldehyde was maintained after a wash-recovery period. Pretreatment of cinnamaldehyde with thiol-containing compounds, such as β-mercaptoethanol or cysteine, blocked the inhibitory activity of cinnamaldehyde. These results suggest that cinnamaldehyde inhibits the activation of GLUT1 by forming a covalent link to target cysteine residue/s. This dual activity of cinnamaldehyde on the transport activity of GLUT1 suggests that cinnamaldehyde is not a major contributor to the anti-diabetic properties of cinnamon.
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Affiliation(s)
- Christina Plaisier
- Department of Chemistry and Biochemistry, Calvin College, 3201 Burton SE, Grand Rapids, MI 49546, USA
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Zhou SH, Fan J, Chen XM, Cheng KJ, Wang SQ. Inhibition of cell proliferation and glucose uptake in human laryngeal carcinoma cells by antisense oligonucleotides against glucose transporter-1. Head Neck 2010; 31:1624-33. [PMID: 19441091 DOI: 10.1002/hed.21137] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Malignant cells show increased glucose uptake in vitro and in vivo, which is thought to be mediated by glucose transporters. In this study, we investigated the effect of plasmid-derived antisense RNA against the Glut-l gene on proliferation and glucose uptake in laryngeal carcinoma Hep-2 cells. METHODS The expression plasmids pcDNA3.1(+)-Glut-1 and pcDNA3.1(+)-anti Glut-1 were constructed. The MTT method was used to assess cell growth inhibition. The expression of Glut-1 mRNA and protein was detected by reverse transcriptase-polymerase chain reaction and Western blotting, respectively. RESULTS After transfection, Glut-1 AS clearly inhibited glucose uptake and cell growth in Hep-2 cells, and we observed a decrease in the expression of Glut-1 mRNA and protein in Hep-2 cells. CONCLUSIONS Glut-1 AS decreases glucose uptake and inhibits the proliferation of Hep-2 cells.
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Affiliation(s)
- Shui-Hong Zhou
- Department of Otolaryngology, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, China
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Watanabe M, Masaoka N, Nakajima Y, Nagaishi M, Yamamoto T. Changes of expression of glucose transporters in the fetal lamb brain after MCI-186 administration to the maternal circulation with 10-min persistent umbilical cord occlusion. J Matern Fetal Neonatal Med 2010; 22:829-36. [PMID: 19637108 DOI: 10.1080/14767050902801702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To evaluate the effect of MCI-186 (3-methyl-1-phenyl-2-pyrazoline-5-one), a potent hydroxyl radical scavenger, administered to the maternal circulation following umbilical cord occlusion in regard to glucose transporter (GLUT) expression. MATERIALS AND METHODS Fourteen instrumented lambs were prepared. In three cases, a 10-min persistent umbilical cord occlusion was performed; 30 min after the insult, fetal brains were extirpated (Group A). Four cases had a 10-min occlusion(Group B) and four cases had 10-min occlusion and were administered MCI-186 to the maternal circulation (Group C).Three days following the insult, the fetal brains were extirpated. The remaining three cases had a sham operation (Group D).Brain tissue sections were stained at the locations of GLUT-1, -3 and -5 and were evaluated by two pathologists. RESULTS The expression of GLUT-1 and -3 significantly increased in the basal ganglia, hippocampi and periventricular region of Group B when compared with that of Group A. The expression of GLUT-1 and -3 in three regions of Group B were significantly higher than that of Group C and D. GLUT-5 was recognised only in Group B. CONCLUSION On the basis of expression of GLUT, the protective effect of MCI-186 on brain injury resulting from hypoxia/ ischemia-reperfusion is documented.
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Affiliation(s)
- Masao Watanabe
- Department of Obstetrics and Gynecology, Tokyo Womnen's Medical University Yachiyo Medical Center, 477-96 Owada-Shinden, Yachiyo Chiba 276-8524, Japan
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Lowengrub JS, Frieboes HB, Jin F, Chuang YL, Li X, Macklin P, Wise SM, Cristini V. Nonlinear modelling of cancer: bridging the gap between cells and tumours. NONLINEARITY 2010; 23:R1-R9. [PMID: 20808719 PMCID: PMC2929802 DOI: 10.1088/0951-7715/23/1/r01] [Citation(s) in RCA: 222] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Despite major scientific, medical and technological advances over the last few decades, a cure for cancer remains elusive. The disease initiation is complex, and including initiation and avascular growth, onset of hypoxia and acidosis due to accumulation of cells beyond normal physiological conditions, inducement of angiogenesis from the surrounding vasculature, tumour vascularization and further growth, and invasion of surrounding tissue and metastasis. Although the focus historically has been to study these events through experimental and clinical observations, mathematical modelling and simulation that enable analysis at multiple time and spatial scales have also complemented these efforts. Here, we provide an overview of this multiscale modelling focusing on the growth phase of tumours and bypassing the initial stage of tumourigenesis. While we briefly review discrete modelling, our focus is on the continuum approach. We limit the scope further by considering models of tumour progression that do not distinguish tumour cells by their age. We also do not consider immune system interactions nor do we describe models of therapy. We do discuss hybrid-modelling frameworks, where the tumour tissue is modelled using both discrete (cell-scale) and continuum (tumour-scale) elements, thus connecting the micrometre to the centimetre tumour scale. We review recent examples that incorporate experimental data into model parameters. We show that recent mathematical modelling predicts that transport limitations of cell nutrients, oxygen and growth factors may result in cell death that leads to morphological instability, providing a mechanism for invasion via tumour fingering and fragmentation. These conditions induce selection pressure for cell survivability, and may lead to additional genetic mutations. Mathematical modelling further shows that parameters that control the tumour mass shape also control its ability to invade. Thus, tumour morphology may serve as a predictor of invasiveness and treatment prognosis.
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Affiliation(s)
- J S Lowengrub
- Department of Biomedical Engineering, Center for Mathematical and Computational Biology, University of California at Irvine, Irvine, CA 92697, USA
| | - H B Frieboes
- School of Health Information Sciences, University of Texas Health Science Center, Houston, TX 77030, USA
- Department of Mathematics, University of California at Irvine, Irvine, CA 92697, USA
| | - F Jin
- School of Health Information Sciences, University of Texas Health Science Center, Houston, TX 77030, USA
- Department of Mathematics, University of California at Irvine, Irvine, CA 92697, USA
| | - Y-L Chuang
- School of Health Information Sciences, University of Texas Health Science Center, Houston, TX 77030, USA
| | - X Li
- Department of Mathematics, University of California at Irvine, Irvine, CA 92697, USA
| | - P Macklin
- School of Health Information Sciences, University of Texas Health Science Center, Houston, TX 77030, USA
| | - S M Wise
- Department of Mathematics, University of Tennessee, Knoxville, TN 37996, USA
| | - V Cristini
- School of Health Information Sciences, University of Texas Health Science Center, Houston, TX 77030, USA
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39
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Endogenous Hypoxia Markers: Case Not Proven! ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 614:127-36. [DOI: 10.1007/978-0-387-74911-2_15] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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40
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Drogat B, Auguste P, Nguyen DT, Bouchecareilh M, Pineau R, Nalbantoglu J, Kaufman RJ, Chevet E, Bikfalvi A, Moenner M. IRE1 signaling is essential for ischemia-induced vascular endothelial growth factor-A expression and contributes to angiogenesis and tumor growth in vivo. Cancer Res 2007; 67:6700-7. [PMID: 17638880 DOI: 10.1158/0008-5472.can-06-3235] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In solid tumors, cancer cells subjected to ischemic conditions trigger distinct signaling pathways contributing to angiogenic stimulation and tumor development. Characteristic features of tumor ischemia include hypoxia and glucose deprivation, leading to the activation of hypoxia-inducible factor-1-dependent signaling pathways and to complex signaling events known as the unfolded protein response. Here, we show that the activation of the endoplasmic reticulum stress sensor IRE1 is a common determinant linking hypoxia- and hypoglycemia-dependent responses to the up-regulation of vascular endothelial growth factor-A (VEGF-A). Tumor cells expressing a dominant-negative IRE1 transgene as well as Ire1alpha-null mouse embryonic fibroblasts were unable to trigger VEGF-A up-regulation upon either oxygen or glucose deprivation. These data correlated with a reduction of tumor angiogenesis and growth in vivo. Our results therefore suggest an essential role for IRE1-dependent signaling pathways in response to ischemia and identify this protein as a potential therapeutic target to control both the angiogenic switch and tumor development.
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Affiliation(s)
- Benjamin Drogat
- INSERM E0113, Université Bordeaux I, Bâtiment B2, Avenue des Facultes, Falence F-33400, France
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41
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Haberkorn U, Hoffend J, Schmidt K, Altmann A, Bonaterra GA, Dimitrakopoulou-Strauss A, Strauss LG, Eisenhut M, Kinscherf R. Changes in glucose metabolism and gene expression after transfer of anti-angiogenic genes in rat hepatoma. Eur J Nucl Med Mol Imaging 2007; 34:2011-23. [PMID: 17701172 DOI: 10.1007/s00259-007-0520-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2007] [Accepted: 06/22/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE Human troponin I (TROP), the soluble receptor for vascular endothelial growth factor (sFLT) and angiostatin (ASTAT) are potent inhibitors of endothelial cell proliferation, angiogenesis and tumour growth in vivo. Transfer of these genes into tumours may induce changes not only in perfusion, but also more general ones such as changes in metabolism. The aim of this study was to assess these reactions using FDG-PET and high-throughput methods such as gene profiling. METHODS We established Morris hepatoma (MH3924A) cell lines expressing TROP, sFLT or ASTAT and quantified (18)F-fluorodeoxyglucose ((18)FDG) uptake by dynamic positron emission tomography (PET) after tumour inoculation in ACI rats. Furthermore, expression of glucose transporter-1 and -3 (GLUT-1 and GLUT-3) as well as hexokinase-1 and -2 were investigated by RT-PCR and immunohistomorphometry. In addition, gene array analyses were performed. RESULTS (18)FDG uptake, vascular fraction and distribution volume were significantly higher in all genetically modified tumours. Immunohistomorphometry showed an increased percentage of hexokinase-1 and -2 as well as GLUT-1 and -3 immunoreactive (ir) cells. Using gene arrays and comparing all three groups of genetically modified tumours, we found upregulated expression of 36 genes related to apoptosis, signal transduction, stress or metabolism. CONCLUSION TROP-, sFLT- or ASTAT-expressing MH3924A tumours show enhanced influx of (18)FDG, which seems to be caused by several factors: enhanced exchange of nutrients between blood and tumour, increased amounts of glucose transporters and hexokinases, and increased expression of genes related to apoptosis, matrix and stress, which induce an increased demand for glucose.
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Affiliation(s)
- Uwe Haberkorn
- Department of Nuclear Medicine, University of Heidelberg, Heidelberg, Germany.
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42
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Wincewicz A, Sulkowska M, Koda M, Kanczuga-Koda L, Witkowska E, Sulkowski S. Significant Coexpression of GLUT-1, Bcl-xL, and Bax in Colorectal Cancer. Ann N Y Acad Sci 2007; 1095:53-61. [PMID: 17404017 DOI: 10.1196/annals.1397.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Hypoxic cancer cells overexpress Glucose transporter 1 (GLUT-1) to accelerate glucose intake mainly for low effective, anaerobic respiration, so that they would not die of oxygen deficiency. Ischemic cell injury triggers apoptosis. Regulators of cell suicide like Bax and Bcl-xL combine their functions to cause apoptosis or to rescue cells from death. GLUT-1, Bax, and Bcl-xL are of prognostic significance in colorectal cancer but they have not been compared, yet. Thus, we aimed to determine eventual correlations between GLUT-1, Bax, and Bcl-xL in association with different clinicopathological features of colorectal cancer patients. Expressions of the proteins were evaluated in specimens of 150 colorectal patients by immunohistochemistry. The levels of tissue expressions were statistically analyzed with Spearman's correlation test. As in group of all the patients, GLUT-1 matched Bcl-xL and Bax in statistically significant manner regardless of different node status, grade of histological differentiation, histopathological type, tumor site, gender and age of patients. GLUT-1 correlated highly with Bcl-xL in both groups of various tumor growth extent: pT1 + pT2 and pT3 + pT4 tumors (P < 0.016, r = 0.6340, P < 0.0001, r = 0.5204, respectively). Bax correlated with GLUT-1 (P < 0.0001, r = 0.4284) and Bcl-xL (P < 0.0001, r = 0.5233) in pT3 and pT4 tumors without any statistical significance in a homologous comparison at pT1 and pT2 stage (P > 0.173, r = 0.1078, P > 0.744, r = 0.1, respectively). Significant coexpression of GLUT-1, Bcl-xL, and Bax could point to cooperation of these regulatory proteins in elimination due to irreversible injury, adaptation to hypoxia, reduction of further damage, and survival of colorectal cancer cells.
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Affiliation(s)
- Andrzej Wincewicz
- Departments of General and Clinical Pathomorphology, Medical University of Bialystok, Waszyngtona St. 13, 15-269 Bialystok, Poland
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43
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Roelofs B, Tidball A, Lindborg AE, TenHarmsel A, Vander Kooy TO, Louters LL. Acute activation of glucose uptake by glucose deprivation in L929 fibroblast cells. Biochimie 2006; 88:1941-6. [PMID: 17010494 DOI: 10.1016/j.biochi.2006.08.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Accepted: 08/17/2006] [Indexed: 11/24/2022]
Abstract
Glucose is a very important energy source for a wide variety of cells, and the ability of cells to respond to changes in glucose availability or other cell stresses is of critical importance. Many mammalian cells respond to acute stress by increasing the V(max) of transport through GLUT1; the most ubiquitously expressed glucose transporter isoform. This study investigated the acute response of glucose uptake to glucose deprivation in L929 fibroblast cells--a cell line that expresses only the GLUT1 transporter. Results indicated that glucose deprivation of only a minute activated glucose uptake 10-fold and reached a maximum of 20-fold within 10 min. The activation was dose dependent and only partially muted by addition of up to 20mM pyruvate as an alternate energy source. In contrast to the kinetics of acute metabolic stress, glucose deprivation decreased the K(m) of transport, but did not alter the V(max). Maximal activation of glucose transport by glucose deprivation was completely additive to activation of transport by methylene blue--a stimulant that increased the V(max) of transport without a change in the K(m). Glucose-deprived activation of glucose transport was not inhibited by wortmannin or herbimycin A, but was completely inhibited by phenylarsine oxide. Altogether, the data indicate that L929 fibroblast cells respond quickly and robustly to the cell stress of glucose deprivation and methylene blue treatment by two distinct activation pathways.
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Affiliation(s)
- Brian Roelofs
- Department of Chemistry and Biochemistry, Calvin College, 3201 Burton SE, Grand Rapids, MI 49546, USA
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44
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Jonathan RA, Wijffels KIEM, Peeters W, de Wilde PCM, Marres HAM, Merkx MAW, Oosterwijk E, van der Kogel AJ, Kaanders JHAM. The prognostic value of endogenous hypoxia-related markers for head and neck squamous cell carcinomas treated with ARCON. Radiother Oncol 2006; 79:288-97. [PMID: 16730088 DOI: 10.1016/j.radonc.2006.04.008] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2005] [Revised: 04/06/2006] [Accepted: 04/19/2006] [Indexed: 11/21/2022]
Abstract
BACKGROUND AND PURPOSE Hypoxic radioresistance is an important cause for treatment failure in a number of tumor types including head and neck cancers. Recent studies suggest that outcome can be improved by oxygenation modifying treatments such as ARCON. A robust endogenous marker of hypoxia might be a valuable aid to select patients for such treatments. The aim of this investigation was to study associations between the putative endogenous hypoxia markers CA-IX, Glut-1 and Glut-3 and clinical tumor and patient characteristics and to evaluate the prognostic value of these markers. PATIENTS AND METHODS Tumor biopsies from 58 patients treated with ARCON in a phase II trial were included. Tumor sections were immunohistochemically stained for CA-IX, Glut-1 and Glut-3. Sections were scored for relative tumor area stained by the markers (CA-IX and Glut-3) and for intensity of staining (Glut-1 and Glut-3). Further, sections were stained for CD34, an endothelial marker to assess microvascular density. RESULTS Staining of CA-IX and Glut-3 was observed at some distance from vessels and adjacent to necrosis. Glut-1 staining was generally very diffuse. The distribution of clinical characteristics was equal between tumors with high and low marker expression. Significant differences were found for locoregional control (P = 0.04) and for freedom of distant metastases (P = 0.02) in favour of patients with high CA-IX positivity (>25% of tumor area). High Glut-3 expression was associated with a better locoregional control (P = 0.04). Higher Glut-1 intensity was associated with an increased rate of distant metastases (P = 0.0005) and a worse overall survival (P = 0.001). CONCLUSIONS The inconsistent associations with outcome of CA-IX and the glucose transporters indicate that different factors play a role in up-regulation of these markers. Compared to studies with conventional treatment, the correlation between CA-IX expression and Glut-3 expression and outcome was reversed after treatment with ARCON. This does not support the potential of any of these proteins as very specific and robust hypoxia markers.
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Affiliation(s)
- Ruth A Jonathan
- Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, The Netherlands
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45
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Bélanger M, Desjardins P, Chatauret N, Butterworth RF. Selectively increased expression of the astrocytic/endothelial glucose transporter protein GLUT1 in acute liver failure. Glia 2006; 53:557-62. [PMID: 16374780 DOI: 10.1002/glia.20310] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Acute liver failure (ALF) is consistently accompanied by alterations in brain energy metabolites and recent nuclear magnetic resonance (NMR) studies suggest disturbances in brain oxidative metabolism in experimental ALF. Glucose transport across the blood-brain barrier is essential to sustain brain energy metabolism and is accomplished by the facilitative glucose transporter GLUT1. To investigate alterations in brain glucose uptake in acute liver failure further, GLUT1 expression and [14C]-2-deoxy-D-glucose uptake were measured in the brains of rats with hepatic devascularization. RT-PCR and Western blot analyses showed significant increases in steady-state levels of GLUT1 mRNA and protein in frontal cortex as early as 6 h following hepatic devascularization, (prior to the onset of brain edema and encephalopathy) which remained elevated at coma stages of encephalopathy. Expression of the astrocytic (45-kDa) and endothelial (55-kDa) forms of GLUT1 was increased as a result of hepatic devascularization. Exposure of cultured astrocytes to pathophysiologically relevant concentrations of ammonia resulted in increased GLUT1 expression, suggesting that elevated ammonia levels are responsible for GLUT1 upregulation in ALF. Increased GLUT1 expression in ALF was selective, since expression of the neuronal glucose transporter GLUT3 and other glucose-regulated proteins (GRP-78 and GRP-94) was unaltered. [14C]-2-deoxy-D-glucose autoradiography revealed increases in cerebral glucose uptake following the induction of GLUT1 in ALF. These results suggest that ammonia-induced increases of GLUT1 expression resulting in increased cerebral glucose uptake occur in ALF and could contribute to the pathophysiological mechanisms responsible for the neurological complications of this condition.
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Affiliation(s)
- Mireille Bélanger
- Neuroscience Research Unit, C.H.U.M. (Hôpital Saint-Luc), Montreal, Quebec, Canada
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46
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Somboonwiwat K, Supungul P, Rimphanitchayakit V, Aoki T, Hirono I, Tassanakajon A. Differentially Expressed Genes in Hemocytes of Vibrio harveyi-challenged Shrimp Penaeus monodon. BMB Rep 2006; 39:26-36. [PMID: 16466635 DOI: 10.5483/bmbrep.2006.39.1.026] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Differential Display PCR technique (DD-PCR) was used for the analysis of altered gene expression in hemocytes of Vibrio harveyi-infected Penaeus monodon. Forty-four combinations of arbitrary and oligo(dT) primers were used to screen for differentially expressed genes. A total of 79 differentially expressed bands could be identified from 33 primer combinations. These included 48 bands (61%) whose expression level increased and 31 bands (39%) decreased after V. harveyi challenge. Subsequently, forty-eight differential display fragments were successfully reamplified and cloned. A total of 267 clones were randomly selected and sequenced. The sequence analysis showed that 85 (31%) out of 267 clones were matched with sequences in the GenBank database which represented 24 different genes with known functions. Among the known genes, glucose transporter 1, interferon-related developmental regulator 1, lysozyme, profilin, SERPINB3, were selected for further confirmation of their differentially expression patterns by real-time PCR. The results showed increasing in expression level of the selected genes in shrimp hemocytes after microbial challenge suggesting the involvement of such genes in bacterial response in shrimp. The anti-lipopolysaccharide factor type 3 (ALFPm3) gene, previously reported in P. monodon (Supungul et al., 2002) was found among the up-regulated genes but diversity due to amino acid changes was observed. Increase in ALFPm3 transcripts upon V. harveyi injection is in accordance with that found in the previous study.
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Affiliation(s)
- Kunlaya Somboonwiwat
- Department of Biochemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
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Totary-Jain H, Naveh-Many T, Riahi Y, Kaiser N, Eckel J, Sasson S. Calreticulin Destabilizes Glucose Transporter-1 mRNA in Vascular Endothelial and Smooth Muscle Cells Under High-Glucose Conditions. Circ Res 2005; 97:1001-8. [PMID: 16210549 DOI: 10.1161/01.res.0000189260.46084.e5] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Substrate autoregulation of glucose transporter-1 (GLUT-1) mRNA and protein expression provides vascular endothelial and smooth muscle cells a sensitive mechanism to adapt their rate of glucose transport in response to changing glycemic conditions. Hyperglycemia-induced downregulation of glucose transport is particularly important in protecting these cells against an excessive influx of glucose and consequently increased intracellular protein glycation and generation of free radicals; both are detrimental in the development of vascular disease in diabetes. We aimed to investigate the molecular mechanism of high glucose–induced downregulation of GLUT-1 mRNA expression in primary bovine aortic vascular endothelial (VEC) and smooth muscle (VSMC) cell cultures. Using RNA mobility shift, UV cross-linking, and in vitro degradation assays, followed by mass-spectrometric analysis, we identified calreticulin as a specific destabilizing
trans
-acting factor that binds to a 10-nucleotide
cis
-acting element (CAE
2181-2190
) in the 3′-untranslated region of GLUT-1 mRNA. Pure calreticulin accelerated the rate of GLUT-1 mRNA-probe degradation in vitro, whereas overexpression of calreticulin in vascular cells decreased significantly the total cell content of GLUT-1 mRNA and protein. The expression of calreticulin was augmented in vascular cells exposed to high glucose in comparison with low-glucose conditions. Similarly, increased expression of calreticulin was observed in aortae of diabetic
Psammomys obesus
in comparison with normoglycemic controls. These data suggest that CAE
2181-2190
–calreticulin complex, which is formed in VSMC and VEC exposed to hyperglycemic conditions, renders GLUT-1 mRNA susceptible to degradation. This interaction underlies the process of downregulation of glucose transport in vascular cells under high-glucose conditions.
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Affiliation(s)
- Hana Totary-Jain
- Department of Pharmacology, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Israel
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Blüher M, Wilson-Fritch L, Leszyk J, Laustsen PG, Corvera S, Kahn CR. Role of Insulin Action and Cell Size on Protein Expression Patterns in Adipocytes. J Biol Chem 2004; 279:31902-9. [PMID: 15131120 DOI: 10.1074/jbc.m404570200] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mice with a fat-specific insulin receptor knock-out (FIRKO) exhibit a polarization of white adipose tissue into two populations of cells, one small (diameter <50 microm) and one large (diameter >100 microm), accompanied by changes in insulin-stimulated glucose uptake, triglyceride synthesis, and lipolysis. To characterize these subclasses of adipocytes, we have used a proteomics approach in which isolated adipocytes from FIRKO and control (IR lox/lox) mice were separated by size, fractionated into cytosolic and membrane subfractions, and analyzed by sucrose gradient, SDS-PAGE, and mass spectrometry. A total of 27 alterations in protein expression at key steps in lipid and energy metabolism could be defined, which were coordinately regulated by adipocyte cell size, impaired insulin signaling, or both. Nine proteins, including vimentin, EH-domain-containing protein 2, elongation factor 2, glucose-regulated protein 78, transketolase, and succinyl-CoA transferase were primarily affected by presence or absence of insulin signaling, whereas 21 proteins, including myosin non-muscle form A, annexin 2, annexin A6, and Hsp47 were regulated in relation to adipocyte size. Of these 27 alterations in protein expression, 14 changes correlated with altered levels of mRNA, whereas the remaining 13 were the result of changes in protein translation or turnover. These data suggest an intrinsic heterogeneity in adipocytes with differences in protein expression patterns caused by transcriptional and post-transcriptional alterations related to insulin action and cellular lipid accumulation.
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Affiliation(s)
- Matthias Blüher
- Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts 02215, USA
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49
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Alpert E, Altman H, Totary H, Gruzman A, Barnea D, Barash V, Sasson S. 4-Hydroxy tempol-induced impairment of mitochondrial function and augmentation of glucose transport in vascular endothelial and smooth muscle cells. Biochem Pharmacol 2004; 67:1985-95. [PMID: 15130774 DOI: 10.1016/j.bcp.2004.02.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2003] [Accepted: 02/02/2004] [Indexed: 11/21/2022]
Abstract
The water-soluble and cell permeable nitroxide derivative 4-hydroxy tempol (TPL) has been shown to reduce or ameliorate oxidative stress-induced dysfunction and damage in vascular endothelial cells. We studied the effects of TPL on glucose transport and metabolism in bovine aortic endothelial (VEC) and smooth muscle cells (VSMC) under normal and high glucose conditions. Normally, these cells operate an autoregulatory protective mechanism that limits the rate of glucose transport under hyperglycemic conditions by decreasing the cell content of their typical glucose transporter GLUT-1 mRNA and protein as well as its plasma membrane abundance. TPL augmented the rate of glucose transport both under normo- and hyperglycemic conditions by increasing GLUT-1 mRNA and protein content and its plasma membrane abundance in both types of cells, leading to an increased flux of glucose into the cells. These effects were found related to ROS-generating and oxidant activities of TPL and to a decreased rate of mitochondrial ATP production under both normo- and hyperglycemic conditions. Since impaired mitochondrial functions, and in particular decreased rate of ATP production, augment the expression of GLUT-1 protein and glucose transport and metabolism, we suggest that the stimulatory effects of TPL in vascular cells results from its unfavorable interactions in the mitochondrion. It is therefore suggested that effects of TPL in cells of cardiovascular system be evaluated in parallel to its adverse effects on glucose and energy metabolism.
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Affiliation(s)
- Evgenia Alpert
- Department of Pharmacology, School of Pharmacy, The Hebrew University-Hadassah Faculty of Medicine, P.O. Box 12272, Jerusalem 91120, Israel
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50
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Vogl-Willis CA, Edwards IJ. High-glucose-induced structural changes in the heparan sulfate proteoglycan, perlecan, of cultured human aortic endothelial cells. Biochim Biophys Acta Gen Subj 2004; 1672:36-45. [PMID: 15056491 DOI: 10.1016/j.bbagen.2004.02.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2003] [Revised: 02/06/2004] [Accepted: 02/13/2004] [Indexed: 02/06/2023]
Abstract
Hyperglycemia is an independent risk factor for diabetes-associated cardiovascular disease. One potential mechanism involves hyperglycemia-induced changes in arterial wall extracellular matrix components leading to increased atherosclerosis susceptibility. A decrease in heparan sulfate (HS) glycosaminoglycans (GAG) has been reported in diabetic arteries. The present studies examined the effects of high glucose on in vitro production of proteoglycans (PG) by aortic endothelial cells. Exposure of cells to high glucose (30 vs. 5 mM glucose) resulted in decreased [(35)S] sodium sulfate incorporation specifically into secreted HSPG. Differences were not due to hyperosmolar effects and no changes were observed in CS/DSPG. Enzymatic procedures, immunoprecipitation and Western analyses demonstrated that high glucose induced changes specifically in the HSPG, perlecan. In double-label experiments, lower sulfate incorporation in high-glucose-treated cells was accompanied by lower [(3)H] glucosamine incorporation into GAG but not lower [(3)H] serine incorporation into PG core proteins. Size exclusion chromatography demonstrated that GAG size was unchanged and GAG sulfation was not reduced. These results indicate that the level of regulation of perlecan by high glucose is posttranslational, involving a modification in molecular structure, possibly a decrease in the number of HS GAG chains on the core protein.
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Affiliation(s)
- Catherine A Vogl-Willis
- Department of Pathology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157, USA
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