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Rodrigues A, Beresford L, Scudamore CL, Yon M. A guide to post-mortem examination procedure in mouse models. Lab Anim 2022; 56:466-470. [PMID: 35360986 DOI: 10.1177/00236772221080827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The main objective of a post mortem is to identify, at a macroscopic level, any anatomical features that characterise mutant or sick mice and to describe lesions contributing to morbidity and mortality. Tissues collected for subsequent examination require appropriate handling and preservation to prevent deterioration. Therefore, efficient routine procedures are essential to facilitate histology and to ensure high-quality samples. In addition, optimised techniques minimise data loss from damaged samples reducing the numbers of animals used and supporting the 3Rs principle of reduction. Here, we describe an optimised method for tissue collection in the mouse. Training tips and points for caution are included.
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2
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Austin A, Beresford L, Price G, Cunningham T, Kalmar B, Yon M. Sectioning and Counting of Motor Neurons in the L3 to L6 Region of the Adult Mouse Spinal Cord. Curr Protoc 2022; 2:e428. [PMID: 35617451 DOI: 10.1002/cpz1.428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Histology is the study of the microscopic structure of tissues. This protocol permits the generation of frozen transverse sections of lumbar spinal cord regions L3 to L6. It enables counting of murine ventral horn lumbar motor neurons in a reproducible manner. Methods include spinal column dissection, hydraulic extrusion, and histological processing. The preparation for cryo-sectioning includes embedding lumbar spinal cord in optimal cutting temperature (OCT) medium. The correct orientation of the tissue is critical as calculating the amount of tissue to discard saved time overall. Specific details regarding section thickness and mounting are described. These requirements not only allow optimum coverage of specific regions but also ensure that no individual motor neuron was counted twice. The Nissl bodies of the motor neurons were stained using gallocyanin. The sections obtained are all of a comparable area and quality assurance is consistent. The specificity of the staining enables the scientist to identify and reliably quantify lumbar motor neurons. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Euthanasia of mouse and isolation of spinal cord Basic Protocol 2: Hydraulic extrusion of the spinal cord Basic Protocol 3: Identification of the lumbar region Basic Protocol 4: Embedding cord in OCT Basic Protocol 5: Collection of frozen sections onto slides Basic Protocol 6: Gallocyanin staining Basic Protocol 7: Motor neuron counting.
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Affiliation(s)
- Adele Austin
- Pathology Department, Mary Lyon Centre, Medical Research Council, Harwell, United Kingdom
| | - Lynn Beresford
- Pathology Department, Mary Lyon Centre, Medical Research Council, Harwell, United Kingdom
| | - Georgia Price
- Mouse Models of Neurodegeneration, Mammalian Genetics Unit, Medical Research Council, Harwell, United Kingdom
| | - Tom Cunningham
- Mouse Models of Neurodegeneration, Mammalian Genetics Unit, Medical Research Council, Harwell, United Kingdom
| | | | - Marianne Yon
- Pathology Department, Mary Lyon Centre, Medical Research Council, Harwell, United Kingdom
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3
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Mušo M, Bentley L, Vizor L, Yon M, Burling K, Barker P, Zolkiewski LAK, Cox RD, Dumbell R. A Wars2 mutant mouse shows a sex and diet specific change in fat distribution, reduced food intake and depot-specific upregulation of WAT browning. Front Physiol 2022; 13:953199. [PMID: 36091365 PMCID: PMC9452902 DOI: 10.3389/fphys.2022.953199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 07/19/2022] [Indexed: 11/21/2022] Open
Abstract
Background: Increased waist-to-hip ratio (WHR) is associated with increased mortality and risk of type 2 diabetes and cardiovascular disease. The TBX15-WARS2 locus has consistently been associated with increased WHR. Previous study of the hypomorphic Wars2 V117L/V117L mouse model found phenotypes including severely reduced fat mass, and white adipose tissue (WAT) browning, suggesting Wars2 could be a potential modulator of fat distribution and WAT browning. Methods: To test for differences in browning induction across different adipose depots of Wars2 V117L/V117L mice, we measured multiple browning markers of a 4-month old chow-fed cohort in subcutaneous and visceral WAT and brown adipose tissue (BAT). To explain previously observed fat mass loss, we also tested for the upregulation of plasma mitokines FGF21 and GDF15 and for differences in food intake in the same cohort. Finally, to test for diet-associated differences in fat distribution, we placed Wars2 V117L/V117L mice on low-fat or high-fat diet (LFD, HFD) and assessed their body composition by Echo-MRI and compared terminal adipose depot weights at 6 months of age. Results: The chow-fed Wars2 V117L/V117L mice showed more changes in WAT browning marker gene expression in the subcutaneous inguinal WAT depot (iWAT) than in the visceral gonadal WAT depot (gWAT). These mice also demonstrated reduced food intake and elevated plasma FGF21 and GDF15, and mRNA from heart and BAT. When exposed to HFD, the Wars2 V117L/V117L mice showed resistance to diet-induced obesity and a male and HFD-specific reduction of gWAT: iWAT ratio. Conclusion: Severe reduction of Wars2 gene function causes a systemic phenotype which leads to upregulation of FGF21 and GDF15, resulting in reduced food intake and depot-specific changes in browning and fat mass.
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Affiliation(s)
- Milan Mušo
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire, United Kingdom
| | - Liz Bentley
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire, United Kingdom.,Mary Lyon Centre at MRC Harwell, Oxfordshire, United Kingdom
| | - Lucie Vizor
- Mary Lyon Centre at MRC Harwell, Oxfordshire, United Kingdom
| | - Marianne Yon
- Mary Lyon Centre at MRC Harwell, Oxfordshire, United Kingdom
| | - Keith Burling
- MRC Metabolic Diseases Unit, Mouse Biochemistry Laboratory, Cambridge, United Kingdom
| | - Peter Barker
- MRC Metabolic Diseases Unit, Mouse Biochemistry Laboratory, Cambridge, United Kingdom
| | | | - Roger D Cox
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire, United Kingdom
| | - Rebecca Dumbell
- Mammalian Genetics Unit, MRC Harwell Institute, Oxfordshire, United Kingdom.,Department of Biosciences, School of Science and Technology, Nottingham Trent University, Nottingham, United Kingdom
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4
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Small KS, Todorčević M, Civelek M, El-Sayed Moustafa JS, Wang X, Simon MM, Fernandez-Tajes J, Mahajan A, Horikoshi M, Hugill A, Glastonbury CA, Quaye L, Neville MJ, Sethi S, Yon M, Pan C, Che N, Vinuela A, Tsai PC, Nag A, Buil A, Thorleifsson G, Raghavan A, Ding Q, Morris AP, Bell JT, Thorsteinsdottir U, Stefansson K, Laakso M, Dahlman I, Arner P, Gloyn AL, Musunuru K, Lusis AJ, Cox RD, Karpe F, McCarthy MI. Author Correction: Regulatory variants at KLF14 influence type 2 diabetes risk via a female-specific effect on adipocyte size and body composition. Nat Genet 2018; 50:1342. [PMID: 30087441 DOI: 10.1038/s41588-018-0180-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In the version of this article originally published, minus signs were missing from the three β-values for BMI given in Table 1. The errors have been corrected in the HTML and PDF versions of the article.
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Affiliation(s)
- Kerrin S Small
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK.
| | - Marijana Todorčević
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Mete Civelek
- Center for Public Health Genomics, Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, USA.,Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Xiao Wang
- Cardiovascular Institute, Department of Medicine, Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Michelle M Simon
- Biocomputing, Medical Research Council Harwell Institute, Oxford, UK
| | | | - Anubha Mahajan
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Momoko Horikoshi
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK.,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Alison Hugill
- Genetics of Type 2 Diabetes, Medical Research Council Harwell Institute, Oxford, UK
| | - Craig A Glastonbury
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Lydia Quaye
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Matt J Neville
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK.,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
| | - Siddharth Sethi
- Biocomputing, Medical Research Council Harwell Institute, Oxford, UK
| | - Marianne Yon
- Genetics of Type 2 Diabetes, Medical Research Council Harwell Institute, Oxford, UK
| | - Calvin Pan
- Department of Human Genetics, University of California, Los Angeles, Los Angeles, CA, USA
| | - Nam Che
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Ana Vinuela
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Pei-Chien Tsai
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Abhishek Nag
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Alfonso Buil
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | | | | | - Qiurong Ding
- CAS Key Laboratory of Nutrition and Metabolism , Institute for Nutritional Sciences, Shanghai Institutes for Biological SciencesChinese Academy of Sciences, Shanghai, PR China
| | - Andrew P Morris
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.,Department of Biostatistics, University of Liverpool, Liverpool, UK
| | - Jordana T Bell
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Unnur Thorsteinsdottir
- deCODE Genetics, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Kari Stefansson
- deCODE Genetics, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | - Markku Laakso
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Ingrid Dahlman
- Department of Medicine,Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Peter Arner
- Department of Medicine,Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Anna L Gloyn
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK.,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK.,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
| | - Kiran Musunuru
- Cardiovascular Institute, Department of Medicine, Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Aldons J Lusis
- Department of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Human Genetics, University of California, Los Angeles, Los Angeles, CA, USA.,Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, USA
| | - Roger D Cox
- Genetics of Type 2 Diabetes, Medical Research Council Harwell Institute, Oxford, UK
| | - Fredrik Karpe
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK.,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
| | - Mark I McCarthy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK. .,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK. .,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK.
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5
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Small KS, Todorčević M, Civelek M, El-Sayed Moustafa JS, Wang X, Simon MM, Fernandez-Tajes J, Mahajan A, Horikoshi M, Hugill A, Glastonbury CA, Quaye L, Neville MJ, Sethi S, Yon M, Pan C, Che N, Viñuela A, Tsai PC, Nag A, Buil A, Thorleifsson G, Raghavan A, Ding Q, Morris AP, Bell JT, Thorsteinsdottir U, Stefansson K, Laakso M, Dahlman I, Arner P, Gloyn AL, Musunuru K, Lusis AJ, Cox R, Karpe F, McCarthy MI. Regulatory variants at KLF14 influence type 2 diabetes risk via a female-specific effect on adipocyte size and body composition. Nat Genet 2018; 50:572-580. [PMID: 29632379 PMCID: PMC5935235 DOI: 10.1038/s41588-018-0088-x] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 02/15/2018] [Indexed: 12/30/2022]
Abstract
Individual risk of type 2 diabetes (T2D) is modified by perturbations to the mass, distribution and function of adipose tissue. To investigate the mechanisms underlying these associations, we explored the molecular, cellular and whole-body effects of T2D-associated alleles near KLF14. We show that KLF14 diabetes-risk alleles act in adipose tissue to reduce KLF14 expression and modulate, in trans, the expression of 385 genes. We demonstrate, in human cellular studies, that reduced KLF14 expression increases pre-adipocyte proliferation but disrupts lipogenesis, and in mice, that adipose tissue-specific deletion of Klf14 partially recapitulates the human phenotype of insulin resistance, dyslipidemia and T2D. We show that carriers of the KLF14 T2D risk allele shift body fat from gynoid stores to abdominal stores and display a marked increase in adipocyte cell size, and that these effects on fat distribution, and the T2D association, are female specific. The metabolic risk associated with variation at this imprinted locus depends on the sex both of the subject and of the parent from whom the risk allele derives.
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Affiliation(s)
- Kerrin S. Small
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK,Corresponding authors: Correspondence should be addressed to K.S.S. () or M.I.M ()
| | - Marijana Todorčević
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK
| | - Mete Civelek
- Center for Public Health Genomics, Department of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, USA,Department of Medicine, University of California, Los Angeles, California, USA
| | | | - Xiao Wang
- Cardiovascular Institute, Department of Medicine, Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Michelle M. Simon
- Biocomputing, Medical Research Council Harwell Institute, Oxford, UK
| | | | - Anubha Mahajan
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Momoko Horikoshi
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Alison Hugill
- Genetics of type 2 diabetes, Medical Research Council Harwell Institute, Oxford, UK
| | - Craig A. Glastonbury
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Lydia Quaye
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Matt J. Neville
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
| | - Siddharth Sethi
- Biocomputing, Medical Research Council Harwell Institute, Oxford, UK
| | - Marianne Yon
- Genetics of type 2 diabetes, Medical Research Council Harwell Institute, Oxford, UK
| | - Calvin Pan
- Department of Human Genetics, University of California, Los Angeles, California, USA
| | - Nam Che
- Department of Medicine, University of California, Los Angeles, California, USA
| | - Ana Viñuela
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Pei-Chien Tsai
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Abhishek Nag
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Alfonso Buil
- Department of Genetic Medicine and Development, University of Geneva Medical School, Geneva, Switzerland
| | | | | | - Qiurong Ding
- CAS Key Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, PR China
| | - Andrew P. Morris
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK,Department of Biostatistics, University of Liverpool, Liverpool, UK
| | - Jordana T. Bell
- Department of Twin Research and Genetic Epidemiology, King's College London, London, UK
| | - Unnur Thorsteinsdottir
- deCODE Genetics, Reykjavik, Iceland,Faculty of Medicine, University of Iceland, Reykjavik Iceland
| | - Kari Stefansson
- deCODE Genetics, Reykjavik, Iceland,Faculty of Medicine, University of Iceland, Reykjavik Iceland
| | - Markku Laakso
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland and Kuopio University Hospital, Kuopio, Finland
| | - Ingrid Dahlman
- Department of Medicine, Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Peter Arner
- Department of Medicine, Huddinge, Karolinska Institutet, Stockholm, Sweden
| | - Anna L. Gloyn
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
| | - Kiran Musunuru
- Cardiovascular Institute, Department of Medicine, Department of Genetics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Aldons J. Lusis
- Department of Medicine, University of California, Los Angeles, California, USA,Department of Human Genetics, University of California, Los Angeles, California, USA,Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, California, USA
| | - Roger Cox
- Genetics of type 2 diabetes, Medical Research Council Harwell Institute, Oxford, UK
| | - Fredrik Karpe
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK
| | - Mark I. McCarthy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford, UK,Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK,Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford, UK,Corresponding authors: Correspondence should be addressed to K.S.S. () or M.I.M ()
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6
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Ashrafi R, Yon M, Pickavance L, Yanni Gerges J, Davis G, Wilding J, Jian K, Zhang H, Hart G, Boyett M. Altered Left Ventricular Ion Channel Transcriptome in a High-Fat-Fed Rat Model of Obesity: Insight into Obesity-Induced Arrhythmogenesis. J Obes 2016; 2016:7127898. [PMID: 27747100 PMCID: PMC5056006 DOI: 10.1155/2016/7127898] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Revised: 06/29/2016] [Accepted: 07/21/2016] [Indexed: 01/03/2023] Open
Abstract
Introduction. Obesity is increasingly common and is associated with an increased prevalence of cardiac arrhythmias. The aim of this study was to see whether in obesity there is proarrhythmic gene expression of ventricular ion channels and related molecules. Methods and Results. Rats were fed on a high-fat diet and compared to control rats on a normal diet (n = 8). After 8 weeks, rats on the high-fat diet showed significantly greater weight gain and higher adiposity. Left ventricle samples were removed at 8 weeks and mRNA expression of ion channels and other molecules was measured using qPCR. Obese rats had significant upregulation of Cav1.2, HCN4, Kir2.1, RYR2, NCX1, SERCA2a, and RYR2 mRNA and downregulation of ERG mRNA. In the case of HCN4, it was confirmed that there was a significant increase in protein expression. The potential effects of the mRNA changes on the ventricular action potential and intracellular Ca2+ transient were predicted using computer modelling. Modelling predicted prolongation of the ventricular action potential and an increase in the intracellular Ca2+ transient, both of which would be expected to be arrhythmogenic. Conclusion. High-fat diet causing obesity results in arrhythmogenic cardiac gene expression of ion channels and related molecules.
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Affiliation(s)
- Reza Ashrafi
- Department of Obesity & Endocrinology, Institute of Ageing and Chronic Disease, Faculty of Health & Life Sciences, University of Liverpool, 4th Floor, UCD, Duncan Building, Daulby Street, Liverpool L69 3GA, UK
- *Reza Ashrafi:
| | - Marianne Yon
- Department of Obesity & Endocrinology, Institute of Ageing and Chronic Disease, Faculty of Health & Life Sciences, University of Liverpool, 4th Floor, UCD, Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Lucy Pickavance
- Department of Obesity & Endocrinology, Institute of Ageing and Chronic Disease, Faculty of Health & Life Sciences, University of Liverpool, 4th Floor, UCD, Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Joseph Yanni Gerges
- Institute of Cardiovascular Sciences, University of Manchester, Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
| | - Gershan Davis
- Department of Obesity & Endocrinology, Institute of Ageing and Chronic Disease, Faculty of Health & Life Sciences, University of Liverpool, 4th Floor, UCD, Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - John Wilding
- Department of Obesity & Endocrinology, Institute of Ageing and Chronic Disease, Faculty of Health & Life Sciences, University of Liverpool, 4th Floor, UCD, Duncan Building, Daulby Street, Liverpool L69 3GA, UK
| | - Kun Jian
- Biological Physics Group, School of Physics & Astronomy, University of Manchester, Schuster Building, Oxford Road, Manchester M13 9PL, UK
| | - Henggui Zhang
- Biological Physics Group, School of Physics & Astronomy, University of Manchester, Schuster Building, Oxford Road, Manchester M13 9PL, UK
| | - George Hart
- Institute of Cardiovascular Sciences, University of Manchester, Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
| | - Mark Boyett
- Institute of Cardiovascular Sciences, University of Manchester, Core Technology Facility, 46 Grafton Street, Manchester M13 9NT, UK
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7
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Krizhanovsky V, Xue W, Zender L, Yon M, Hernando E, Lowe SW. Implications of cellular senescence in tissue damage response, tumor suppression, and stem cell biology. Cold Spring Harb Symp Quant Biol 2008; 73:513-22. [PMID: 19150958 PMCID: PMC3285266 DOI: 10.1101/sqb.2008.73.048] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Cellular senescence is characterized by an irreversible cell cycle arrest that, when bypassed by mutation, contributes to cellular immortalization. Activated oncogenes induce a hyperproliferative response, which might be one of the senescence cues. We have found that expression of such an oncogene, Akt, causes senescence in primary mouse hepatoblasts in vitro. Additionally, AKT-driven tumors undergo senescence in vivo following p53 reactivation and show signs of differentiation. In another in vivo system, i.e., liver fibrosis, hyperproliferative signaling through AKT might be a driving force of the senescence in activated hepatic stellate cells. Senescent cells up-regulate and secrete molecules that, on the one hand, can reinforce the arrest and, on the other hand, can signal to an innate immune system to clear the senescent cells. The mechanisms governing senescence and immortalization are overlapping with those regulating self-renewal and differentiation. These respective control mechanisms, or their disregulation, are involved in multiple pathological conditions including fibrosis, wound healing, and cancer. Understanding extracellular cues that regulate these processes may enable new therapies for these conditions.
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Affiliation(s)
- V Krizhanovsky
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York 11724, USA
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8
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Han YH, Yon M, Hyun TH. Folate intake estimated with an updated database and its association to blood folate and homocysteine in Korean college students. Eur J Clin Nutr 2004; 59:246-54. [PMID: 15483632 DOI: 10.1038/sj.ejcn.1602065] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To measure folate content in cooked foods commonly consumed in Korea for evaluating its relation to folate nutriture of college students. DESIGN Folate content in 32 raw and cooked foods was measured by microbiological assay after trienzyme extraction. These values and the previously published values of 110 raw foods commonly consumed in Korea were used to update the currently available food tables to estimate dietary folate intake of 106 students based on a 3-day 24-h recall. The association of folate intake with blood folate and homocysteine concentrations was evaluated. SETTING Cheongju, Korea. SUBJECTS Healthy college students aged 18 to 27 y old (44 males and 62 females). RESULTS The average folate loss in 32 foods caused by cooking was 29%. The mean daily dietary folate intakes estimated with an updated database were 406 and 305 mug in males and females, respectively. About 10% of both male and female students showed low serum folate (<6.8 nmol/l). Folate intake was positively correlated with serum and erythrocyte folate concentrations in female students (r=0.27 and 0.29, respectively, P<0.05), and negatively correlated with serum homocysteine in male students (r=-0.41, P<0.05). CONCLUSIONS Mean dietary folate intake was higher than those of previous studies since the database was updated using values obtained with trienzyme extraction. Folate intake for the general population should be re-evaluated using reliable food folate values obtained with trienzyme extraction.
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Affiliation(s)
- Y H Han
- Department of Food and Nutrition, Chungbuk National University, Gaeshin-dong, Cheongju, Korea
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9
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Atkins CM, Yon M, Groome NP, Sweatt JD. Regulation of myelin basic protein phosphorylation by mitogen-activated protein kinase during increased action potential firing in the hippocampus. J Neurochem 1999; 73:1090-7. [PMID: 10461899 DOI: 10.1046/j.1471-4159.1999.0731090.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Myelin basic protein (MBP) phosphorylation is a complex regulatory process that modulates the contribution of MBP to the stability of the myelin sheath. Recent research has demonstrated the modulation of MBP phosphorylation by mitogen-activated protein kinase (MAPK) during myelinogenesis and in the demyelinating disease multiple sclerosis. Here we investigated the physiological regulation of MBP phosphorylation by MAPK during neuronal activity in the alveus, the myelinated output fibers of the hippocampus. Using a phosphospecific antibody that recognizes the predominant MAPK phosphorylation site in MBP, Thr95, we found that MBP phosphorylation is regulated by high-frequency stimulation but not low-frequency stimulation of the alveus. This change was blocked by application of tetrodotoxin, indicating that action potential propagation in axons is required. It is interesting that the change in MBP phosphorylation was attenuated by the reactive oxygen species scavengers superoxide dismutase and catalase and the nitric oxide synthase inhibitor N-nitro-L-arginine. Removal of extracellular calcium also blocked the changes in MBP phosphorylation. Thus, we propose that during periods of increased neuronal activity, calcium activates axonal nitric oxide synthase, which generates the intercellular messengers nitric oxide and superoxide and regulates the phosphorylation state of MBP by MAPK.
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Affiliation(s)
- C M Atkins
- Division of Neuroscience, Baylor College of Medicine, Houston, Texas 77030, USA
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Yon M, Ackerley CA, Mastronardi FG, Groome N, Moscarello MA. Identification of a mitogen-activated protein kinase site in human myelin basic protein in situ. J Neuroimmunol 1996; 65:55-9. [PMID: 8642064 DOI: 10.1016/0165-5728(95)00183-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Ultrastructural localization of a specific phosphorylated isomer of myelin basic protein (MBP) has been achieved with a monoclonal antibody specific for human MBP sequence, 89-105, in which Thr98 was phosphorylated. Cryosections of human brain white matter revealed that gold particles were found localized almost exclusively to the major dense line demonstrating that threonine 98 in the sequence Thr-Pro-Arg-Thr-Pro-Pro-Pro, a mitogen-activated protein kinase-specific site, was phosphorylated in vivo. In two cases of multiple sclerosis, the density of gold particles in myelin was reduced by about 30%, in one case by 42%, and by 80% in a fourth case. However, gold labelling was seen in areas of demyelination suggesting that the phosphorylated threonyl peptide was protected from degradation.
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Affiliation(s)
- M Yon
- School of Biological and Molecular Sciences, Oxford Brookes University, Headington, UK
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Abstract
Phosphorylation is one of a number of post-translational modifications resulting in charge microheterogeneity of myelin basic protein (MBP). This phosphorylation is claimed to destabilise the compact myelin sheath by decreasing the interaction of membrane bilayers, thereby creating or maintaining pockets of cytoplasm. To further investigate and localise MBP phosphorylation to discrete regions of the myelin sheath we raised a monoclonal antibody with specificity for a known phosphorylation site in MBP. A synthetic peptide was made by Fmoc peptide chemistry and phosphorylation of Thr98 was achieved on the resin by the global phosphorylation methodology, utilising dibenzyl-N,N-diethylphosphoramidite phosphitylation and t-butylhydroperoxide oxidation. The peptide coupled to tuberculin was used to immunise mice for monoclonal antibody production. The selected hybridoma (Clone P12) secreted an IgG2a antibody which reacted strongly with the phosphorylated immunogen and with phosphorylated fractions of bovine MBP obtained by ion exchange chromatography. The antibody had minimal reactivity with the unphosphorylated peptide; the same peptide phosphorylated at another site Ser102; a preparation of unphosphorylated MBP obtained by ion exchange chromatography; and with an irrelevant phosphorylated protein (histone). Similar phosphorylation state-specific monoclonal antibodies could be made to recognise other specific phosphorylation sites in MBP or other proteins. It is planned to use these antibodies to quantify and locate the extent of MBP phosphorylation in normal and multiple sclerosis myelin.
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Affiliation(s)
- M Yon
- School of Biological and Molecular Sciences, Oxford Brookes University, Headington, UK
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Yon M, Davignon JP. [Medicinal plants of long ago specific to dentistry]. Rev Fr Prothes Dent 1985:74-5. [PMID: 3860895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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