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Tabish TA, Xu J, Campbell CK, Abbas M, Myers WK, Didwal P, Carugo D, Xie F, Crabtree MJ, Stride E, Lygate CA. pH-sensitive release of nitric oxide gas using peptide-graphene co-assembled hybrid nanosheets. Nitric Oxide 2024; 147:42-50. [PMID: 38631610 DOI: 10.1016/j.niox.2024.04.008] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Revised: 04/04/2024] [Accepted: 04/11/2024] [Indexed: 04/19/2024]
Abstract
Nitric oxide (NO) donating drugs such as organic nitrates have been used to treat cardiovascular diseases for more than a century. These donors primarily produce NO systemically. It is however sometimes desirable to control the amount, location, and time of NO delivery. We present the design of a novel pH-sensitive NO release system that is achieved by the synthesis of dipeptide diphenylalanine (FF) and graphene oxide (GO) co-assembled hybrid nanosheets (termed as FF@GO) through weak molecular interactions. These hybrid nanosheets were characterised by using X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, zeta potential measurements, X-ray photoelectron spectroscopy, scanning and transmission electron microscopies. The weak molecular interactions, which include electrostatic, hydrogen bonding and π-π stacking, are pH sensitive due to the presence of carboxylic acid and amine functionalities on GO and the dipeptide building blocks. Herein, we demonstrate that this formulation can be loaded with NO gas with the dipeptide acting as an arresting agent to inhibit NO burst release at neutral pH; however, at acidic pH it is capable of releasing NO at the rate of up to 0.6 μM per minute, comparable to the amount of NO produced by healthy endothelium. In conclusion, the innovative conjugation of dipeptide with graphene can store and release NO gas under physiologically relevant concentrations in a pH-responsive manner. pH responsive NO-releasing organic-inorganic nanohybrids may prove useful for the treatment of cardiovascular diseases and other pathologies.
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Affiliation(s)
- Tanveer A Tabish
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford, OX3 7BN, United Kingdom.
| | - Jiamin Xu
- Department of Materials and London Centre for Nanotechnology, Imperial College London, London, SW7 2AZ, United Kingdom
| | - Christopher K Campbell
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), The Botnar Research Centre, University of Oxford, Oxford, OX3 7LD, United Kingdom
| | - Manzar Abbas
- Department of Chemistry, Khalifa University of Science and Technology, P.O. Box, 127788, Abu Dhabi, United Arab Emirates
| | - William K Myers
- Centre for Advanced Electron Spin Resonance (CAESR), Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3QR, United Kingdom
| | - Pravin Didwal
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, United Kingdom
| | - Dario Carugo
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), The Botnar Research Centre, University of Oxford, Oxford, OX3 7LD, United Kingdom
| | - Fang Xie
- Department of Materials and London Centre for Nanotechnology, Imperial College London, London, SW7 2AZ, United Kingdom
| | - Mark J Crabtree
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford, OX3 7BN, United Kingdom; Department of Biochemical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - Eleanor Stride
- Institute of Biomedical Engineering (IBME), Department of Engineering Science, University of Oxford, Oxford, OX3 7LD, United Kingdom
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford, OX3 7BN, United Kingdom
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Tabish TA, Hussain MZ, Zervou S, Myers WK, Tu W, Xu J, Beer I, Huang WE, Chandrawati R, Crabtree MJ, Winyard PG, Lygate CA. S-nitrosocysteamine-functionalised porous graphene oxide nanosheets as nitric oxide delivery vehicles for cardiovascular applications. Redox Biol 2024; 72:103144. [PMID: 38613920 PMCID: PMC11026843 DOI: 10.1016/j.redox.2024.103144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Accepted: 03/29/2024] [Indexed: 04/15/2024] Open
Abstract
Nitric oxide (NO) is a key signalling molecule released by vascular endothelial cells that is essential for vascular health. Low NO bioactivity is associated with cardiovascular diseases, such as hypertension, atherosclerosis, and heart failure and NO donors are a mainstay of drug treatment. However, many NO donors are associated with the development of tolerance and adverse effects, so new formulations for controlled and targeted release of NO would be advantageous. Herein, we describe the design and characterisation of a novel NO delivery system via the reaction of acidified sodium nitrite with thiol groups that had been introduced by cysteamine conjugation to porous graphene oxide nanosheets, thereby generating S-nitrosated nanosheets. An NO electrode, ozone-based chemiluminescence and electron paramagnetic resonance spectroscopy were used to measure NO released from various graphene formulations, which was sustained at >5 × 10-10 mol cm-2 min-1 for at least 3 h, compared with healthy endothelium (cf. 0.5-4 × 10-10 mol cm-2 min-1). Single cell Raman micro-spectroscopy showed that vascular endothelial and smooth muscle cells (SMCs) took up graphene nanostructures, with intracellular NO release detected via a fluorescent NO-specific probe. Functionalised graphene had a dose-dependent effect to promote proliferation in endothelial cells and to inhibit growth in SMCs, which was associated with cGMP release indicating intracellular activation of canonical NO signalling. Chemiluminescence detected negligible production of toxic N-nitrosamines. Our findings demonstrate the utility of porous graphene oxide as a NO delivery vehicle to release physiologically relevant amounts of NO in vitro, thereby highlighting the potential of these formulations as a strategy for the treatment of cardiovascular diseases.
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Affiliation(s)
- Tanveer A Tabish
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Headington, Oxford, OX3 7BN, United Kingdom.
| | - Mian Zahid Hussain
- School of Natural Sciences and Catalysis Research Centre, Department of Chemistry, Chair of Inorganic and Metal-Organic Chemistry, Technical University of Munich (TUM), Lichtenbergstraße 4, 85748, Garching, Germany
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Headington, Oxford, OX3 7BN, United Kingdom
| | - William K Myers
- Centre for Advanced Electron Spin Resonance (CAESR), Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3QR, United Kingdom
| | - Weiming Tu
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, United Kingdom
| | - Jiabao Xu
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, United Kingdom; James Watt School of Engineering, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - Irina Beer
- Institute of Water Chemistry, Chair of Analytical Chemistry and Water Chemistry, Technical University of Munich, Lichtenbergstraße 4, 85748, Garching, Germany
| | - Wei E Huang
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, United Kingdom
| | - Rona Chandrawati
- School of Chemical Engineering and Australian Centre for Nanomedicine (ACN), The University of New South Wales (UNSW), Sydney, NSW, 2052, Australia
| | - Mark J Crabtree
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Headington, Oxford, OX3 7BN, United Kingdom; Department of Biochemical Sciences, School of Biosciences and Medicine, University of Surrey, Guildford, GU2 7XH, United Kingdom
| | - Paul G Winyard
- University of Exeter Medical School, Faculty of Health and Life Sciences, University of Exeter, Exeter, EX1 2LU, United Kingdom
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Headington, Oxford, OX3 7BN, United Kingdom
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Lygate CA. Maintaining energy provision in the heart: the creatine kinase system in ischaemia-reperfusion injury and chronic heart failure. Clin Sci (Lond) 2024; 138:491-514. [PMID: 38639724 DOI: 10.1042/cs20230616] [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] [Received: 12/18/2023] [Revised: 03/25/2024] [Accepted: 04/11/2024] [Indexed: 04/20/2024]
Abstract
The non-stop provision of chemical energy is of critical importance to normal cardiac function, requiring the rapid turnover of ATP to power both relaxation and contraction. Central to this is the creatine kinase (CK) phosphagen system, which buffers local ATP levels to optimise the energy available from ATP hydrolysis, to stimulate energy production via the mitochondria and to smooth out mismatches between energy supply and demand. In this review, we discuss the changes that occur in high-energy phosphate metabolism (i.e., in ATP and phosphocreatine) during ischaemia and reperfusion, which represents an acute crisis of energy provision. Evidence is presented from preclinical models that augmentation of the CK system can reduce ischaemia-reperfusion injury and improve functional recovery. Energetic impairment is also a hallmark of chronic heart failure, in particular, down-regulation of the CK system and loss of adenine nucleotides, which may contribute to pathophysiology by limiting ATP supply. Herein, we discuss the evidence for this hypothesis based on preclinical studies and in patients using magnetic resonance spectroscopy. We conclude that the correlative evidence linking impaired energetics to cardiac dysfunction is compelling; however, causal evidence from loss-of-function models remains equivocal. Nevertheless, proof-of-principle studies suggest that augmentation of CK activity is a therapeutic target to improve cardiac function and remodelling in the failing heart. Further work is necessary to translate these findings to the clinic, in particular, a better understanding of the mechanisms by which the CK system is regulated in disease.
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Affiliation(s)
- Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, United Kingdom
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Tabish TA, Lygate CA. Mitochondria-targeted nanomedicines for cardiovascular applications. Nanomedicine (Lond) 2023; 18:2101-2104. [PMID: 38059500 DOI: 10.2217/nnm-2023-0321] [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: 12/08/2023] Open
Abstract
Tweetable abstract Mitochondria are increasingly a target for drug delivery in cardiovascular diseases. This editorial describes how a nanomedicine approach may improve drug potency and efficacy in a safe and controlled manner.
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Affiliation(s)
- Tanveer A Tabish
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford, OX3 7BN, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford, OX3 7BN, UK
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Tabish TA, Zhu Y, Shukla S, Kadian S, Sangha GS, Lygate CA, Narayan RJ. Graphene nanocomposites for real-time electrochemical sensing of nitric oxide in biological systems. Appl Phys Rev 2023; 10:041310. [PMID: 38229764 PMCID: PMC7615530 DOI: 10.1063/5.0162640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Nitric oxide (NO) signaling plays many pivotal roles impacting almost every organ function in mammalian physiology, most notably in cardiovascular homeostasis, inflammation, and neurological regulation. Consequently, the ability to make real-time and continuous measurements of NO is a prerequisite research tool to understand fundamental biology in health and disease. Despite considerable success in the electrochemical sensing of NO, challenges remain to optimize rapid and highly sensitive detection, without interference from other species, in both cultured cells and in vivo. Achieving these goals depends on the choice of electrode material and the electrode surface modification, with graphene nanostructures recently reported to enhance the electrocatalytic detection of NO. Due to its single-atom thickness, high specific surface area, and highest electron mobility, graphene holds promise for electrochemical sensing of NO with unprecedented sensitivity and specificity even at sub-nanomolar concentrations. The non-covalent functionalization of graphene through supermolecular interactions, including π-π stacking and electrostatic interaction, facilitates the successful immobilization of other high electrolytic materials and heme biomolecules on graphene while maintaining the structural integrity and morphology of graphene sheets. Such nanocomposites have been optimized for the highly sensitive and specific detection of NO under physiologically relevant conditions. In this review, we examine the building blocks of these graphene-based electrochemical sensors, including the conjugation of different electrolytic materials and biomolecules on graphene, and sensing mechanisms, by reflecting on the recent developments in materials and engineering for real-time detection of NO in biological systems.
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Affiliation(s)
- Tanveer A. Tabish
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Yangzhi Zhu
- Terasaki Institute for Biomedical Innovation, Los Angeles, California 90064, USA
| | - Shubhangi Shukla
- Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Raleigh, North Carolina 27695-7907, USA
| | - Sachin Kadian
- Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Raleigh, North Carolina 27695-7907, USA
| | - Gurneet S. Sangha
- Fischell Department of Bioengineering, University of Maryland, 8278 Paint Branch Dr., College Park, Maryland 20742, USA
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation (BHF) Centre of Research Excellence, University of Oxford, Oxford OX3 7BN, United Kingdom
| | - Roger J. Narayan
- Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, Raleigh, North Carolina 27695-7907, USA
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Farzi M, Coveney S, Afzali M, Zdora M, Lygate CA, Rau C, Frangi AF, Dall'Armellina E, Teh I, Schneider JE. Measuring cardiomyocyte cellular characteristics in cardiac hypertrophy using diffusion-weighted MRI. Magn Reson Med 2023; 90:2144-2157. [PMID: 37345727 PMCID: PMC10962572 DOI: 10.1002/mrm.29775] [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] [Received: 01/23/2023] [Revised: 05/05/2023] [Accepted: 06/02/2023] [Indexed: 06/23/2023]
Abstract
PURPOSE This paper presents a hierarchical modeling approach for estimating cardiomyocyte major and minor diameters and intracellular volume fraction (ICV) using diffusion-weighted MRI (DWI) data in ex vivo mouse hearts. METHODS DWI data were acquired on two healthy controls and two hearts 3 weeks post transverse aortic constriction (TAC) using a bespoke diffusion scheme with multiple diffusion times (Δ $$ \Delta $$ ), q-shells and diffusion encoding directions. Firstly, a bi-exponential tensor model was fitted separately at each diffusion time to disentangle the dependence on diffusion times from diffusion weightings, that is, b-values. The slow-diffusing component was attributed to the restricted diffusion inside cardiomyocytes. ICV was then extrapolated atΔ = 0 $$ \Delta =0 $$ using linear regression. Secondly, given the secondary and the tertiary diffusion eigenvalue measurements for the slow-diffusing component obtained at different diffusion times, major and minor diameters were estimated assuming a cylinder model with an elliptical cross-section (ECS). High-resolution three-dimensional synchrotron X-ray imaging (SRI) data from the same specimen was utilized to evaluate the biophysical parameters. RESULTS Estimated parameters using DWI data were (control 1/control 2 vs. TAC 1/TAC 2): major diameter-17.4μ $$ \mu $$ m/18.0μ $$ \mu $$ m versus 19.2μ $$ \mu $$ m/19.0μ $$ \mu $$ m; minor diameter-10.2μ $$ \mu $$ m/9.4μ $$ \mu $$ m versus 12.8μ $$ \mu $$ m/13.4μ $$ \mu $$ m; and ICV-62%/62% versus 68%/47%. These findings were consistent with SRI measurements. CONCLUSION The proposed method allowed for accurate estimation of biophysical parameters suggesting cardiomyocyte diameters as sensitive biomarkers of hypertrophy in the heart.
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Affiliation(s)
- Mohsen Farzi
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Sam Coveney
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Maryam Afzali
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of PsychologyCardiff UniversityCardiffUK
| | - Marie‐Christine Zdora
- Diamond Light Source Ltd.Harwell Science and Innovation CampusDidcotUK
- Department of Physics & AstronomyUniversity College LondonLondonUK
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK
| | - Christoph Rau
- Diamond Light Source Ltd.Harwell Science and Innovation CampusDidcotUK
| | - Alejandro F. Frangi
- Centre for Computational Imaging and Simulation Technologies in Biomedicine (CISTIB), School of ComputingUniversity of LeedsLeedsUK
| | - Erica Dall'Armellina
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Irvin Teh
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Jürgen E. Schneider
- Biomedical Imaging Science Department, Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
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Maguire ML, McAndrew DJ, Lake HA, Ostrowski PJ, Zervou S, Neubauer S, Lygate CA, Schneider JE. Synergistic effect on cardiac energetics by targeting the creatine kinase system: in vivo application of high-resolution 31P-CMRS in the mouse. J Cardiovasc Magn Reson 2023; 25:6. [PMID: 36740688 PMCID: PMC9900916 DOI: 10.1186/s12968-023-00911-6] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 01/05/2023] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Phosphorus cardiovascular magnetic resonance spectroscopy (31P-CMRS) has emerged as an important tool for the preclinical assessment of myocardial energetics in vivo. However, the high rate and diminutive size of the mouse heart is a challenge, resulting in low resolution and poor signal-to-noise. Here we describe a refined high-resolution 31P-CMRS technique and apply it to a novel double transgenic mouse (dTg) with elevated myocardial creatine and creatine kinase (CK) activity. We hypothesised a synergistic effect to augment energetic status, evidenced by an increase in the ratio of phosphocreatine-to-adenosine-triphosphate (PCr/ATP). METHODS AND RESULTS Single transgenic Creatine Transporter overexpressing (CrT-OE, n = 7) and dTg mice (CrT-OE and CK, n = 6) mice were anaesthetised with isoflurane to acquire 31P-CMRS measurements of the left ventricle (LV) utilising a two-dimensional (2D), threefold under-sampled density-weighted chemical shift imaging (2D-CSI) sequence, which provided high-resolution data with nominal voxel size of 8.5 µl within 70 min. (1H-) cine-CMR data for cardiac function assessment were obtained in the same imaging session. Under a separate examination, mice received invasive haemodynamic assessment, after which tissue was collected for biochemical analysis. Myocardial creatine levels were elevated in all mouse hearts, but only dTg exhibited significantly elevated CK activity, resulting in a 51% higher PCr/ATP ratio in heart (3.01 ± 0.96 vs. 2.04 ± 0.57-mean ± SD; dTg vs. CrT-OE), that was absent from adjacent skeletal muscle. No significant differences were observed for any parameters of LV structure and function, confirming that augmentation of CK activity does not have unforeseen consequences for the heart. CONCLUSIONS We have developed an improved 31P-CMRS methodology for the in vivo assessment of energetics in the murine heart which enabled high-resolution imaging within acceptable scan times. Mice over-expressing both creatine and CK in the heart exhibited a synergistic elevation in PCr/ATP that can now be tested for therapeutic potential in models of chronic heart failure.
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Affiliation(s)
- Mahon L Maguire
- Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Philip J Ostrowski
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK.
- British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, UK.
| | - Jurgen E Schneider
- Experimental and Preclinical Imaging Centre (ePIC), Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK.
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Monga S, Valkovič L, Tyler D, Lygate CA, Rider O, Myerson SG, Neubauer S, Mahmod M. Insights Into the Metabolic Aspects of Aortic Stenosis With the Use of Magnetic Resonance Imaging. JACC Cardiovasc Imaging 2022; 15:2112-2126. [PMID: 36481080 PMCID: PMC9722407 DOI: 10.1016/j.jcmg.2022.04.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 02/25/2022] [Accepted: 04/29/2022] [Indexed: 01/13/2023]
Abstract
Pressure overload in aortic stenosis (AS) encompasses both structural and metabolic remodeling and increases the risk of decompensation into heart failure. A major component of metabolic derangement in AS is abnormal cardiac substrate use, with down-regulation of fatty acid oxidation, increased reliance on glucose metabolism, and subsequent myocardial lipid accumulation. These changes are associated with energetic and functional cardiac impairment in AS and can be assessed with the use of cardiac magnetic resonance spectroscopy (MRS). Proton MRS allows the assessment of myocardial triglyceride content and creatine concentration. Phosphorous MRS allows noninvasive in vivo quantification of the phosphocreatine-to-adenosine triphosphate ratio, a measure of cardiac energy status that is reduced in patients with severe AS. This review summarizes the changes to cardiac substrate and high-energy phosphorous metabolism and how they affect cardiac function in AS. The authors focus on the role of MRS to assess these metabolic changes, and potentially guide future (cellular) metabolic therapy in AS.
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Affiliation(s)
- Shveta Monga
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Ladislav Valkovič
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Damian Tyler
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; Wellcome Centre for Human Genetics, Oxford, United Kingdom
| | - Oliver Rider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Saul G Myerson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Masliza Mahmod
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.
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McAndrew DJ, Lake HA, Zervou S, Schwedhelm E, Schneider JE, Neubauer S, Lygate CA. Homoarginine and creatine deficiency do not exacerbate murine ischaemic heart failure. ESC Heart Fail 2022; 10:189-199. [PMID: 36178450 PMCID: PMC9871656 DOI: 10.1002/ehf2.14183] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/23/2022] [Accepted: 09/15/2022] [Indexed: 01/27/2023] Open
Abstract
AIMS Low levels of homoarginine and creatine are associated with heart failure severity in humans, but it is unclear to what extent they contribute to pathophysiology. Both are synthesized via L-arginine:glycine amidinotransferase (AGAT), such that AGAT-/- mice have a combined creatine and homoarginine deficiency. We hypothesized that this would be detrimental in the setting of chronic heart failure. METHODS AND RESULTS Study 1: homoarginine deficiency-female AGAT-/- and wild-type mice were given creatine-supplemented diet so that both had normal myocardial creatine levels, but only AGAT-/- had low plasma homoarginine. Myocardial infarction (MI) was surgically induced and left ventricular (LV) structure and function assessed at 6-7 weeks by in vivo imaging and haemodynamics. Study 2: homoarginine and creatine-deficiency-as before, but AGAT-/- mice were given creatine-supplemented diet until 1 week post-MI, when 50% were changed to a creatine-free diet. Both groups therefore had low homoarginine levels, but one group also developed lower myocardial creatine levels. In both studies, all groups had LV remodelling and dysfunction commensurate with the development of chronic heart failure, for example, LV dilatation and mean ejection fraction <20%. However, neither homoarginine deficiency alone or in combination with creatine deficiency had a significant effect on mortality, LV remodelling, or on any indices of contractile and lusitropic function. CONCLUSIONS Low levels of homoarginine and creatine do not worsen chronic heart failure arguing against a major causative role in disease progression. This suggests that it is unnecessary to correct hArg deficiency in patients with heart failure, although supra-physiological levels may still be beneficial.
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Affiliation(s)
- Debra J. McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK,British Heart Foundation Centre for Research ExcellenceUniversity of OxfordOxfordUK,Wellcome Centre for Human GeneticsRoosevelt DriveOxfordOX3 7BNUK
| | - Hannah A. Lake
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK,British Heart Foundation Centre for Research ExcellenceUniversity of OxfordOxfordUK,Wellcome Centre for Human GeneticsRoosevelt DriveOxfordOX3 7BNUK
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK,British Heart Foundation Centre for Research ExcellenceUniversity of OxfordOxfordUK,Wellcome Centre for Human GeneticsRoosevelt DriveOxfordOX3 7BNUK
| | - Edzard Schwedhelm
- Institute of Clinical Pharmacology and ToxicologyUniversity Medical Center Hamburg‐EppendorfHamburgGermany
| | - Jurgen E. Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK,Experimental and Preclinical Imaging Centre (ePIC), Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK,British Heart Foundation Centre for Research ExcellenceUniversity of OxfordOxfordUK
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of MedicineUniversity of OxfordOxfordUK,British Heart Foundation Centre for Research ExcellenceUniversity of OxfordOxfordUK,Wellcome Centre for Human GeneticsRoosevelt DriveOxfordOX3 7BNUK
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Nitz K, Lacy M, Bianchini M, Wichapong K, Kücükgöze IA, Bonfiglio CA, Migheli R, Wu Y, Burger C, Li Y, Forné I, Ammar C, Janjic A, Mohanta S, Duchene J, Heemskerk JWM, Megens RTA, Schwedhelm E, Huveneers S, Lygate CA, Santovito D, Zimmer R, Imhof A, Weber C, Lutgens E, Atzler D. The Amino Acid Homoarginine Inhibits Atherogenesis by Modulating T-Cell Function. Circ Res 2022; 131:701-712. [PMID: 36102188 DOI: 10.1161/circresaha.122.321094] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Amino acid metabolism is crucial for inflammatory processes during atherogenesis. The endogenous amino acid homoarginine is a robust biomarker for cardiovascular outcome and mortality with high levels being protective. However, the underlying mechanisms remain elusive. We investigated the effect of homoarginine supplementation on atherosclerotic plaque development with a particular focus on inflammation. METHODS Female ApoE-deficient mice were supplemented with homoarginine (14 mg/L) in drinking water starting 2 weeks before and continuing throughout a 6-week period of Western-type diet feeding. Control mice received normal drinking water. Immunohistochemistry and flow cytometry were used for plaque- and immunological phenotyping. T cells were characterized using mass spectrometry-based proteomics, by functional in vitro approaches, for example, proliferation and migration/chemotaxis assays as well as by super-resolution microscopy. RESULTS Homoarginine supplementation led to a 2-fold increase in circulating homoarginine concentrations. Homoarginine-treated mice exhibited reduced atherosclerosis in the aortic root and brachiocephalic trunk. A substantial decrease in CD3+ T cells in the atherosclerotic lesions suggested a T-cell-related effect of homoarginine supplementation, which was mainly attributed to CD4+ T cells. Macrophages, dendritic cells, and B cells were not affected. CD4+ T-cell proteomics and subsequent pathway analysis together with in vitro studies demonstrated that homoarginine profoundly modulated the spatial organization of the T-cell actin cytoskeleton and increased filopodia formation via inhibition of Myh9 (myosin heavy chain 9). Further mechanistic studies revealed an inhibition of T-cell proliferation as well as a striking impairment of the migratory capacities of T cells in response to relevant chemokines by homoarginine, all of which likely contribute to its atheroprotective effects. CONCLUSIONS Our study unravels a novel mechanism by which the amino acid homoarginine reduces atherosclerosis, establishing that homoarginine modulates the T-cell cytoskeleton and thereby mitigates T-cell functions important during atherogenesis. These findings provide a molecular explanation for the beneficial effects of homoarginine in atherosclerotic cardiovascular disease.
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Affiliation(s)
- Katrin Nitz
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.)
| | - Michael Lacy
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.).,Department of Medical Laboratory Sciences, Virginia Commonwealth University, Richmond (M.L.)
| | - Mariaelvy Bianchini
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Kanin Wichapong
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, the Netherlands (K.W., J.W.M.H., C.W.)
| | - Irem Avcilar Kücükgöze
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Cecilia A Bonfiglio
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.)
| | - Roberta Migheli
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Yuting Wu
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Carina Burger
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Yuanfang Li
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Ignasi Forné
- Biomedical Center Munich, Department of Molecular Biology (I.F., A.I.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Constantin Ammar
- Institute of Bioinformatics, Department of Informatics (C.A., R.Z.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Aleksandar Janjic
- Anthropology & Human Genomics, Department of Biology II (A.J.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Sarajo Mohanta
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Johan Duchene
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.)
| | - Johan W M Heemskerk
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, the Netherlands (K.W., J.W.M.H., C.W.)
| | - Remco T A Megens
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,Department of Biomedical Engineering, CARIM, Maastricht University, Maastricht, the Netherlands (R.T.A.M.)
| | - Edzard Schwedhelm
- Department of Clinical Pharmacology and Toxicology, University Medical Centre Hamburg-Eppendorf, Germany (E.S.).,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Hamburg/Kiel/Lübeck, Germany (E.S.)
| | - Stephan Huveneers
- Department of Medical Biochemistry, Amsterdam University Medical Centre, Amsterdam Cardiovascular Sciences, the Netherlands (S.H.)
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and the BHF Centre of Research Excellence, University of Oxford, United Kingdom (C.A.L.)
| | - Donato Santovito
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.)
| | - Ralf Zimmer
- Institute of Bioinformatics, Department of Informatics (C.A., R.Z.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Axel Imhof
- Biomedical Center Munich, Department of Molecular Biology (I.F., A.I.), Ludwig-Maximilians-Universität, Munich, Germany
| | - Christian Weber
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.).,Department of Medical Laboratory Sciences, Virginia Commonwealth University, Richmond (M.L.)
| | - Esther Lutgens
- DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.).,Department of Cardiovascular Medicine, Experimental Cardiovascular Immunology Laboratory, Mayo Clinic, Rochester, MN (E.L.)
| | - Dorothee Atzler
- Institute for Cardiovascular Prevention (K.N., M.L., M.B., I.A.K., C.A.B., R.M., Y.W., C.B., Y.L., S.M., J.D., R.T.A.M., D.S., C.W., E.L., D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,Walther Straub Institute of Pharmacology and Toxicology (D.A.), Ludwig-Maximilians-Universität, Munich, Germany.,DZHK (Deutsches Zentrum für Herz-Kreislauf-Forschung e.V.), partner site Munich Heart Alliance, Munich, Germany (K.N., M.L., C.A.B., J.D., D.S., C.W., E.L., D.A.)
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11
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Lygate CA, Lake HA, McAndrew DJ, Neubauer S, Zervou S. Influence of homoarginine on creatine accumulation and biosynthesis in the mouse. Front Nutr 2022; 9:969702. [PMID: 36017222 PMCID: PMC9395972 DOI: 10.3389/fnut.2022.969702] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 06/16/2022] [Accepted: 07/21/2022] [Indexed: 12/24/2022] Open
Abstract
Organisms obtain creatine from their diet or by de novo synthesis via AGAT (L-arginine:glycine amidinotransferase) and GAMT (Guanidinoacetate N-methyltrasferase) in kidney and liver, respectively. AGAT also synthesizes homoarginine (hArg), low levels of which predict poor outcomes in human cardiovascular disease, while supplementation maintains contractility in murine heart failure. However, the expression pattern of AGAT has not been systematically studied in mouse tissues and nothing is known about potential feedback interactions between creatine and hArg. Herein, we show that C57BL/6J mice express AGAT and GAMT in kidney and liver respectively, whereas pancreas was the only organ to express appreciable levels of both enzymes, but no detectable transmembrane creatine transporter (Slc6A8). In contrast, kidney, left ventricle (LV), skeletal muscle and brown adipose tissue must rely on creatine transporter for uptake, since biosynthetic enzymes are not expressed. The effects of creatine and hArg supplementation were then tested in wild-type and AGAT knockout mice. Homoarginine did not alter creatine accumulation in plasma, LV or kidney, whereas in pancreas from AGAT KO, the addition of hArg resulted in higher levels of tissue creatine than creatine-supplementation alone (P < 0.05). AGAT protein expression in kidney was downregulated by creatine supplementation (P < 0.05), consistent with previous reports of end-product repression. For the first time, we show that hArg supplementation causes a similar down-regulation of AGAT protein (P < 0.05). These effects on AGAT were absent in the pancreas, suggesting organ specific mechanisms of regulation. These findings highlight the potential for interactions between creatine and hArg that may have implications for the use of dietary supplements and other therapeutic interventions.
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Affiliation(s)
- Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
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12
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Farzi M, Mcclymont D, Whittington H, Zdora MC, Khazin L, Lygate CA, Rau C, Dall'Armellina E, Teh I, Schneider JE. Assessing Myocardial Microstructure With Biophysical Models of Diffusion MRI. IEEE Trans Med Imaging 2021; 40:3775-3786. [PMID: 34270420 DOI: 10.1109/tmi.2021.3097907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Biophysical models are a promising means for interpreting diffusion weighted magnetic resonance imaging (DW-MRI) data, as they can provide estimates of physiologically relevant parameters of microstructure including cell size, volume fraction, or dispersion. However, their application in cardiac microstructure mapping (CMM) has been limited. This study proposes seven new two-compartment models with combination of restricted cylinder models and a diffusion tensor to represent intra- and extracellular spaces, respectively. Three extended versions of the cylinder model are studied here: cylinder with elliptical cross section (ECS), cylinder with Gamma distributed radii (GDR), and cylinder with Bingham distributed axes (BDA). The proposed models were applied to data in two fixed mouse hearts, acquired with multiple diffusion times, q-shells and diffusion encoding directions. The cylinderGDR-pancake model provided the best performance in terms of root mean squared error (RMSE) reducing it by 25% compared to diffusion tensor imaging (DTI). The cylinderBDA-pancake model represented anatomical findings closest as it also allows for modelling dispersion. High-resolution 3D synchrotron X-ray imaging (SRI) data from the same specimen was utilized to evaluate the biophysical models. A novel tensor-based registration method is proposed to align SRI structure tensors to the MR diffusion tensors. The consistency between SRI and DW-MRI parameters demonstrates the potential of compartment models in assessing physiologically relevant parameters.
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13
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Lygate CA. The Pitfalls of in vivo Cardiac Physiology in Genetically Modified Mice - Lessons Learnt the Hard Way in the Creatine Kinase System. Front Physiol 2021; 12:685064. [PMID: 34054587 PMCID: PMC8160301 DOI: 10.3389/fphys.2021.685064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 04/22/2021] [Indexed: 12/30/2022] Open
Abstract
In order to fully understand gene function, at some point, it is necessary to study the effects in an intact organism. The creation of the first knockout mouse in the late 1980's gave rise to a revolution in the field of integrative physiology that continues to this day. There are many complex choices when selecting a strategy for genetic modification, some of which will be touched on in this review, but the principal focus is to highlight the potential problems and pitfalls arising from the interpretation of in vivo cardiac phenotypes. As an exemplar, we will scrutinize the field of cardiac energetics and the attempts to understand the role of the creatine kinase (CK) energy buffering and transport system in the intact organism. This story highlights the confounding effects of genetic background, sex, and age, as well as the difficulties in interpreting knockout models in light of promiscuous proteins and metabolic redundancy. It will consider the dose-dependent effects and unintended consequences of transgene overexpression, and the need for experimental rigour in the context of in vivo phenotyping techniques. It is intended that this review will not only bring clarity to the field of cardiac energetics, but also aid the non-expert in evaluating and critically assessing data arising from in vivo genetic modification.
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Affiliation(s)
- Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
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14
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Zervou S, McAndrew DJ, Whittington HJ, Lake HA, Park KC, Cha KM, Ostrowski PJ, Eykyn TR, Schneider JE, Neubauer S, Lygate CA. Subtle Role for Adenylate Kinase 1 in Maintaining Normal Basal Contractile Function and Metabolism in the Murine Heart. Front Physiol 2021; 12:623969. [PMID: 33867998 PMCID: PMC8044416 DOI: 10.3389/fphys.2021.623969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/15/2021] [Indexed: 11/22/2022] Open
Abstract
Aims Adenylate kinase 1 (AK1) catalyses the reaction 2ADP ↔ ATP + AMP, extracting extra energy under metabolic stress and promoting energetic homeostasis. We hypothesised that increased AK1 activity would have negligible effects at rest, but protect against ischaemia/reperfusion (I/R) injury. Methods and Results Cardiac-specific AK1 overexpressing mice (AK1-OE) had 31% higher AK1 activity (P = 0.009), with unchanged total creatine kinase and citrate synthase activities. Male AK1-OE exhibited mild in vivo dysfunction at baseline with lower LV pressure, impaired relaxation, and contractile reserve. LV weight was 19% higher in AK1-OE males due to higher tissue water content in the absence of hypertrophy or fibrosis. AK1-OE hearts had significantly raised creatine, unaltered total adenine nucleotides, and 20% higher AMP levels (P = 0.05), but AMP-activated protein kinase was not activated (P = 0.85). 1H-NMR revealed significant differences in LV metabolite levels compared to wild-type, with aspartate, tyrosine, sphingomyelin, cholesterol all elevated, whereas taurine and triglycerides were significantly lower. Ex vivo global no-flow I/R, caused four-of-seven AK1-OE hearts to develop terminal arrhythmia (cf. zero WT), yet surviving AK1-OE hearts had improved functional recovery. However, AK1-OE did not influence infarct size in vivo and arrhythmias were only observed ex vivo, probably as an artefact of adenine nucleotide loss during cannulation. Conclusion Modest elevation of AK1 may improve functional recovery following I/R, but has unexpected impact on LV weight, function and metabolite levels under basal resting conditions, suggesting a more nuanced role for AK1 underpinning myocardial energy homeostasis and not just as a response to stress.
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Affiliation(s)
- Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Hannah J Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Kyung Chan Park
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom.,Department of Physiology Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Kuan Minn Cha
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Philip J Ostrowski
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Thomas R Eykyn
- British Heart Foundation Centre for Research Excellence, King's College London, St. Thomas Hospital, London, United Kingdom
| | - Jürgen E Schneider
- Experimental and Preclinical Imaging Centre (ePIC), Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.,British Heart Foundation Centre for Research Excellence, University of Oxford, Oxford, United Kingdom
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15
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Carnicer R, Duglan D, Ziberna K, Recalde A, Reilly S, Simon JN, Mafrici S, Arya R, Rosello-Lleti E, Chuaiphichai S, Tyler D, Lygate CA, Channon KM, Casadei B. BH4 Increases nNOS Activity and Preserves Left Ventricular Function in Diabetes. Circ Res 2021; 128:585-601. [PMID: 33494625 PMCID: PMC7612785 DOI: 10.1161/circresaha.120.316656] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 01/25/2021] [Indexed: 12/20/2022]
Abstract
RATIONALE In diabetic patients, heart failure with predominant left ventricular (LV) diastolic dysfunction is a common complication for which there is no effective treatment. Oxidation of the NOS (nitric oxide synthase) cofactor tetrahydrobiopterin (BH4) and dysfunctional NOS activity have been implicated in the pathogenesis of the diabetic vascular and cardiomyopathic phenotype. OBJECTIVE Using mice models and human myocardial samples, we evaluated whether and by which mechanism increasing myocardial BH4 availability prevented or reversed LV dysfunction induced by diabetes. METHODS AND RESULTS In contrast to the vascular endothelium, BH4 levels, superoxide production, and NOS activity (by liquid chromatography) did not differ in the LV myocardium of diabetic mice or in atrial tissue from diabetic patients. Nevertheless, the impairment in both cardiomyocyte relaxation and [Ca2+]i (intracellular calcium) decay and in vivo LV function (echocardiography and tissue Doppler) that developed in wild-type mice 12 weeks post-diabetes induction (streptozotocin, 42-45 mg/kg) was prevented in mGCH1-Tg (mice with elevated myocardial BH4 content secondary to trangenic overexpression of GTP-cyclohydrolase 1) and reversed in wild-type mice receiving oral BH4 supplementation from the 12th to the 18th week after diabetes induction. The protective effect of BH4 was abolished by CRISPR/Cas9-mediated knockout of nNOS (the neuronal NOS isoform) in mGCH1-Tg. In HEK (human embryonic kidney) cells, S-nitrosoglutathione led to a PKG (protein kinase G)-dependent increase in plasmalemmal density of the insulin-independent glucose transporter GLUT-1 (glucose transporter-1). In cardiomyocytes, mGCH1 overexpression induced a NO/sGC (soluble guanylate cyclase)/PKG-dependent increase in glucose uptake via GLUT-1, which was instrumental in preserving mitochondrial creatine kinase activity, oxygen consumption rate, LV energetics (by 31phosphorous magnetic resonance spectroscopy), and myocardial function. CONCLUSIONS We uncovered a novel mechanism whereby myocardial BH4 prevents and reverses LV diastolic and systolic dysfunction associated with diabetes via an nNOS-mediated increase in insulin-independent myocardial glucose uptake and utilization. These findings highlight the potential of GCH1/BH4-based therapeutics in human diabetic cardiomyopathy. Graphic Abstract: A graphic abstract is available for this article.
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Affiliation(s)
| | - Drew Duglan
- Cardiovascular Medicine, University of Oxford
| | | | | | | | | | | | - Ritu Arya
- Cardiovascular Medicine, University of Oxford
| | | | | | - Damian Tyler
- Physiology, Anatomy and Genetics, University of Oxford
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Branovets J, Karro N, Barsunova K, Laasmaa M, Lygate CA, Vendelin M, Birkedal R. Cardiac expression and location of hexokinase changes in a mouse model of pure creatine deficiency. Am J Physiol Heart Circ Physiol 2021; 320:H613-H629. [PMID: 33337958 DOI: 10.1152/ajpheart.00188.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 11/10/2020] [Accepted: 12/03/2020] [Indexed: 02/06/2023]
Abstract
Creatine kinase (CK) is considered the main phosphotransfer system in the heart, important for overcoming diffusion restrictions and regulating mitochondrial respiration. It is substrate limited in creatine-deficient mice lacking l-arginine:glycine amidinotransferase (AGAT) or guanidinoacetate N-methyltranferase (GAMT). Our aim was to determine the expression, activity, and mitochondrial coupling of hexokinase (HK) and adenylate kinase (AK), as these represent alternative energy transfer systems. In permeabilized cardiomyocytes, we assessed how much endogenous ADP generated by HK, AK, or CK stimulated mitochondrial respiration and how much was channeled to mitochondria. In whole heart homogenates, and cytosolic and mitochondrial fractions, we measured the activities of AK, CK, and HK. Lastly, we assessed the expression of the major HK, AK, and CK isoforms. Overall, respiration stimulated by HK, AK, and CK was ∼25, 90, and 80%, respectively, of the maximal respiration rate, and ∼20, 0, and 25%, respectively, was channeled to the mitochondria. The activity, distribution, and expression of HK, AK, and CK did not change in GAMT knockout (KO) mice. In AGAT KO mice, we found no changes in AK, but we found a higher HK activity in the mitochondrial fraction, greater expression of HK I, but a lower stimulation of respiration by HK. Our findings suggest that mouse hearts depend less on phosphotransfer systems to facilitate ADP flux across the mitochondrial membrane. In AGAT KO mice, which are a model of pure creatine deficiency, the changes in HK may reflect changes in metabolism as well as influence mitochondrial regulation and reactive oxygen species production.NEW & NOTEWORTHY In creatine-deficient AGAT-/- and GAMT-/- mice, the myocardial creatine kinase system is substrate limited. It is unknown whether subcellular localization and mitochondrial ADP channeling by hexokinase and adenylate kinase may compensate as alternative phosphotransfer systems. Our results show no changes in adenylate kinase, which is the main alternative to creatine kinase in heart. However, we found increased expression and activity of hexokinase I in AGAT-/- cardiomyocytes. This could affect mitochondrial regulation and reactive oxygen species production.
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Affiliation(s)
- Jelena Branovets
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia
| | - Niina Karro
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia
| | - Karina Barsunova
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia
| | - Martin Laasmaa
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Marko Vendelin
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia
| | - Rikke Birkedal
- Laboratory of Systems Biology, Institute of Cybernetics, Tallinn University of Technology, Tallinn, Estonia
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Laasmaa M, Branovets J, Barsunova K, Karro N, Lygate CA, Birkedal R, Vendelin M. Altered calcium handling in cardiomyocytes from arginine-glycine amidinotransferase-knockout mice is rescued by creatine. Am J Physiol Heart Circ Physiol 2021; 320:H805-H825. [PMID: 33275525 DOI: 10.1152/ajpheart.00300.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 10/30/2020] [Accepted: 11/23/2020] [Indexed: 01/14/2023]
Abstract
The creatine kinase system facilitates energy transfer between mitochondria and the major ATPases in the heart. Creatine-deficient mice, which lack arginine-glycine amidinotransferase (AGAT) to synthesize creatine and homoarginine, exhibit reduced cardiac contractility. We studied how the absence of a functional CK system influences calcium handling in isolated cardiomyocytes from AGAT-knockouts and wild-type littermates as well as in AGAT-knockout mice receiving lifelong creatine supplementation via the food. Using a combination of whole cell patch clamp and fluorescence microscopy, we demonstrate that the L-type calcium channel (LTCC) current amplitude and voltage range of activation were significantly lower in AGAT-knockout compared with wild-type littermates. Additionally, the inactivation of LTCC and the calcium transient decay were significantly slower. According to our modeling results, these changes can be reproduced by reducing three parameters in knockout mice when compared with wild-type: LTCC conductance, the exchange constant of Ca2+ transfer between subspace and cytosol, and SERCA activity. Because tissue expression of LTCC and SERCA protein were not significantly different between genotypes, this suggests the involvement of posttranslational regulatory mechanisms or structural reorganization. The AGAT-knockout phenotype of calcium handling was fully reversed by dietary creatine supplementation throughout life. Our results indicate reduced calcium cycling in cardiomyocytes from AGAT-knockouts and suggest that the creatine kinase system is important for the development of calcium handling in the heart.NEW & NOTEWORTHY Creatine-deficient mice lacking arginine-glycine amidinotransferase exhibit compromised cardiac function. Here, we show that this is at least partially due to an overall slowing of calcium dynamics. Calcium influx into the cytosol via the L-type calcium current (LTCC) is diminished, and the rate of the sarcoendoplasmic reticulum calcium ATPase (SERCA) pumping calcium back into the sarcoplasmic reticulum is slower. The expression of LTCC and SERCA did not change, suggesting that the changes are regulatory.
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Affiliation(s)
- Martin Laasmaa
- Laboratory of Systems Biology, Department of Cybernetics, School of Science, Tallinn University of Technology, Tallinn, Estonia
| | - Jelena Branovets
- Laboratory of Systems Biology, Department of Cybernetics, School of Science, Tallinn University of Technology, Tallinn, Estonia
| | - Karina Barsunova
- Laboratory of Systems Biology, Department of Cybernetics, School of Science, Tallinn University of Technology, Tallinn, Estonia
| | - Niina Karro
- Laboratory of Systems Biology, Department of Cybernetics, School of Science, Tallinn University of Technology, Tallinn, Estonia
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, and the British Heart Foundation Centre of Research Excellence, University of Oxford, Tallinn, United Kingdom
| | - Rikke Birkedal
- Laboratory of Systems Biology, Department of Cybernetics, School of Science, Tallinn University of Technology, Tallinn, Estonia
| | - Marko Vendelin
- Laboratory of Systems Biology, Department of Cybernetics, School of Science, Tallinn University of Technology, Tallinn, Estonia
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Peterzan MA, Clarke WT, Lygate CA, Lake HA, Lau JYC, Miller JJ, Johnson E, Rayner JJ, Hundertmark MJ, Sayeed R, Petrou M, Krasopoulos G, Srivastava V, Neubauer S, Rodgers CT, Rider OJ. Cardiac Energetics in Patients With Aortic Stenosis and Preserved Versus Reduced Ejection Fraction. Circulation 2020; 141:1971-1985. [PMID: 32438845 PMCID: PMC7294745 DOI: 10.1161/circulationaha.119.043450] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Supplemental Digital Content is available in the text. Why some but not all patients with severe aortic stenosis (SevAS) develop otherwise unexplained reduced systolic function is unclear. We investigate the hypothesis that reduced creatine kinase (CK) capacity and flux is associated with this transition.
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Affiliation(s)
- Mark A Peterzan
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
| | - William T Clarke
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences (W.T.C.), University of Oxford, United Kingdom
| | | | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine (H.A.L.), University of Oxford, United Kingdom
| | - Justin Y C Lau
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
| | - Jack J Miller
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
| | - Errin Johnson
- Dunn School of Pathology (E.J.), University of Oxford, United Kingdom
| | - Jennifer J Rayner
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
| | - Moritz J Hundertmark
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
| | - Rana Sayeed
- Department of Cardiothoracic Surgery, Oxford Heart Centre, John Radcliffe Hospital, United Kingdom (R.S., G.K., V.S.)
| | - Mario Petrou
- Department of Cardiothoracic Surgery, Royal Brompton and Harefield National Health Service Foundation Trust, London, United Kingdom (M.P.)
| | - George Krasopoulos
- Department of Cardiothoracic Surgery, Oxford Heart Centre, John Radcliffe Hospital, United Kingdom (R.S., G.K., V.S.)
| | - Vivek Srivastava
- Department of Cardiothoracic Surgery, Oxford Heart Centre, John Radcliffe Hospital, United Kingdom (R.S., G.K., V.S.)
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
| | | | - Oliver J Rider
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine (M.A.P., J.Y.C.L., J.J.M., J.J.R., M.J.H., S.N., O.J.R.), University of Oxford, United Kingdom
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Aksentijević D, Zervou S, Eykyn TR, McAndrew DJ, Wallis J, Schneider JE, Neubauer S, Lygate CA. Age-Dependent Decline in Cardiac Function in Guanidinoacetate- N-Methyltransferase Knockout Mice. Front Physiol 2020; 10:1535. [PMID: 32038270 PMCID: PMC6985570 DOI: 10.3389/fphys.2019.01535] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [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: 09/09/2019] [Accepted: 12/05/2019] [Indexed: 01/15/2023] Open
Abstract
Aim Guanidinoacetate N-methyltransferase (GAMT) is the second essential enzyme in creatine (Cr) biosynthesis. Short-term Cr deficiency is metabolically well tolerated as GAMT–/– mice exhibit normal exercise capacity and response to ischemic heart failure. However, we hypothesized long-term consequences of Cr deficiency and/or accumulation of the Cr precursor guanidinoacetate (GA). Methods Cardiac function and metabolic profile were studied in GAMT–/– mice >1 year. Results In vivo LV catheterization revealed lower heart rate and developed pressure in aging GAMT–/– but normal lung weight and survival versus age-matched controls. Electron microscopy indicated reduced mitochondrial volume density in GAMT–/– hearts (P < 0.001), corroborated by lower mtDNA copy number (P < 0.004), and citrate synthase activity (P < 0.05), however, without impaired mitochondrial respiration. Furthermore, myocardial energy stores and key ATP homeostatic enzymes were barely altered, while pathology was unrelated to oxidative stress since superoxide production and protein carbonylation were unaffected. Gene expression of PGC-1α was 2.5-fold higher in GAMT–/– hearts while downstream genes were not activated, implicating a dysfunction in mitochondrial biogenesis signaling. This was normalized by 10 days of dietary Cr supplementation, as were all in vivo functional parameters, however, it was not possible to differentiate whether relief from Cr deficiency or GA toxicity was causative. Conclusion Long-term Cr deficiency in GAMT–/– mice reduces mitochondrial volume without affecting respiratory function, most likely due to impaired biogenesis. This is associated with hemodynamic changes without evidence of heart failure, which may represent an acceptable functional compromise in return for reduced energy demand in aging mice.
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Affiliation(s)
- Dunja Aksentijević
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine and Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Sevasti Zervou
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine and Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Thomas R Eykyn
- Department of Imaging Chemistry and Biology, School of Biomedical Engineering and Imaging Sciences, King's College London, St Thomas' Hospital, London, United Kingdom
| | - Debra J McAndrew
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine and Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Julie Wallis
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine and Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Jurgen E Schneider
- Experimental and Preclinical Imaging Centre, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, United Kingdom
| | - Stefan Neubauer
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine and Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Craig A Lygate
- Radcliffe Department of Medicine, Division of Cardiovascular Medicine and Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
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Peterzan MA, Clarke WT, Lygate CA, Lake HA, Lau JYC, Johnson E, Rayner JJ, Hundertmark MJ, Sayeed RA, Petrou M, Krasopoulos G, Srivastava V, Neubauer S, Rodgers CT, Rider OJ. P2272Determinants of left ventricular ATP availability measured in vivo and ex vivo in patients with severe aortic stenosis: correlation of creatine kinase activity with LVEF and ATP diffusion distance. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
The transition to systolic failure in severe aortic stenosis (AS) increases mortality. There are currently no reliable markers of transition, and the guideline LVEF <50% threshold for intervention in asymptomatic severe AS does not capture all subjects at increased risk. In animal models, reduced ATP delivery capacity through creatine kinase (CK) is important, with modest increases in CK capacity conferring cardioprotection. ATP may also diffuse (independent of CK) from mitochondria to the contractile site. We have performed the first human study to test whether ATP diffusion distance relates to CK activity and whether CK activity is reduced in low LVEF severe AS.
Methods
19 patients with severe AS, LVEF ≥55% (AS-pEF, mean±SD LVEF 63±5%, mean gradient 48±14 mmHg) and 10 with severe AS, LVEF <55% (AS-rEF, LVEF 42±8%, mean gradient 32±11) underwent 31P-MRS for CK rate constant (kf) and phosphocreatine/ATP (PCr/ATP) ratio, and MRI for LV volumes. LV biopsies were taken during AVR and analysed for CK total activity, CK isoforms, total creatine, and citrate synthase (CS) activity. 9 biopsies also underwent serial block face scanning electron microscopy and mitochondria-sarcomere 3D distance distributions were plotted. Results were compared to 24 controls (LVEF 61±4%), of which 4 had LV biopsy (3 severe MS, 1 LA myxoma, MS-pEF). Surgical patients had flow-limiting atheroma excluded with invasive angiography and prior myocardial infarction excluded with late gadolinium enhancement MRI.
Results
When compared to controls, both CK total activity and CS activity were lower in AS-pEF (by 27% and 23% respectively, both p<0.05, Panels A-B). Although PCr/ATP reduced in AS-pEF (by 20%, p<0.001, panel C), kf (panel D) and CK flux estimated by kf × total creatine were not different. CK-MB expression reduced in AS-pEF (19 vs 27% of total CK, p=0.003), reflecting compensatory increases in CK-MM (p=0.26) and CK-BB (p=0.18) in the face of reduced CK activity.
AS-rEF was associated with further reduction in both CK and CS activities (by 32% and 22% respectively, both p<0.05, Panels A-B), but no differences in PCr/ATP, CK kf or relative CK isozyme expression were seen. There were no significant between-group differences in total creatine (Panel E). Overall this suggests that CK reserve and oxidative capacity potentially reduce in pressure overload, with further falls commensurate with systolic dysfunction.
When median mitochondria-sarcomere ATP diffusion distances were plotted against CK total activity a strong positive correlation was observed (r=0.86, p=0.003, Panel F). This suggests a compensatory reduction in diffusion distance develops when CK activity falls.
Conclusions
Transition to failure in severe AS is associated with lower oxidative capacity and maximal ATP delivery capacity through CK. Despite compensatory falls in ATP diffusion distance and altered CK isozyme expression, these changes may underlie susceptibility to EF decline in AS.
Acknowledgement/Funding
British Heart Foundation Clinical Research Training Fellowship (FS/15/80/31803) and Programme Grant (RG/18/12/34040).
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Affiliation(s)
- M A Peterzan
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - W T Clarke
- University of Oxford, Oxford, United Kingdom
| | - C A Lygate
- University of Oxford, Oxford, United Kingdom
| | - H A Lake
- University of Oxford, Oxford, United Kingdom
| | - J Y C Lau
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - E Johnson
- University of Oxford, Oxford, United Kingdom
| | - J J Rayner
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - M J Hundertmark
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - R A Sayeed
- John Radcliffe Hospital, Oxford, United Kingdom
| | - M Petrou
- John Radcliffe Hospital, Oxford, United Kingdom
| | | | | | - S Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - C T Rodgers
- University of Cambridge, Wolfson Brain Imaging Centre, Cambridge, United Kingdom
| | - O J Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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Peterzan MA, Clarke WT, Lygate CA, Lake HA, Rayner JJ, Hundertmark MJ, Apps AP, Sayeed RA, Petrou M, Krasopoulos G, Srivastava V, Neubauer S, Rodgers CT, Rider OJ. P1611Non-invasive predictors of LV biopsy-obtained creatine kinase activity in patients with non-failing and failing myocardial hypertrophy. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Myocardial creatine kinase (CK) activity represents an important metabolic reserve: it correlates closely with contractile reserve and post-ischaemic function, keeps cytosolic [ADP] low, and optimises the free energy for ATP hydrolysis. It may also contribute to the transition to failure in the heart hypertrophied by chronic haemodynamic overload; modest up-regulation has been shown to be cardio-protective.
Total CK activity measurement requires chemical freeze-and-extract methods, which destroy tissue, precluding repeated measures. To date, non-invasive assessments of human myocardial CK flux (calculated as kf × [PCr], where kf is the pseudo-first-order forward rate constant measured by 31P-magnetic resonance spectroscopy (MRS) have not assessed creatine content or total CK activity. Thus we aimed to validate kf measurement against total CK activity and investigate predictors of CK activity.
Methods
39 subjects (median age 71, range 43–84) undergoing clinically indicated cardiac surgery had CK total activity measured from LV biopsy. 31 had severe AS (10 with impaired LVEF); 2 had severe primary MR; 5 had severe mitral stenosis (2 with impaired LVEF) and 1 had an LA mass. 35 of 39 contributed triplicate datasets: CK total activity, kf (31P-MRS TRiST sequence at 3T) and LV volumes (cine-MRI, 3T Siemens). 27 had severe AS (8 with impaired LVEF); other groups were the same. Exclusion criteria were prior myocardial infarction and flow-limiting coronary disease. Flash-frozen LV biopsies obtained within 15 min of cardiopulmonary bypass were analysed for CK total activity, total creatine, and citrate synthase (CS) activity (a marker of oxidative phosphorylation capacity).
Results
Multiple, novel correlations were observed between CK total activity (IU/mg protein) and CS activity (r=0.87, p=9e-13), total creatine (r=0.59, p=8e-5), kf (r=0.42, p=0.013), total creatine × kf (r=0.64, p=4e-5), LVESVi (r=−0.52, p=8e-4), LVEF (r=0.48, p=0.002) and LVMi (r=−0.42, p=0.009) (Panels A-E) (LVEDVi and non-indexed counterparts were also significant correlates.) The most predictive linear regression model incorporating elements of the CK rate equation included total creatine (nmol/mg protein), kf (/s), and kf × LVESVi (ml/m2) (adjusted R2=0.56, beta=0.426, 0.618, −1.968 and p=0.001, 5e-5, 0.003 respectively, Panel F).
Figure 1
Conclusions
These results are the first evidence of agreement between non-invasive estimates of human cardiac CK activity (kf) and freeze-extracted chemical methods. The key original finding is that it is feasible to attempt to predict CK capacity in vivo by using a combination of techniques (creatine by 1H MRS, CK kf by 31P-MRS and LVESVi by cine imaging). The key insight is that CK capacity is best estimated not simply from what the rate equation would predict (creatine and kf), but that other factors relating to failing contractility reduce CK activity independently from creatine content and enzyme kf.
Acknowledgement/Funding
British Heart Foundation Clinical Research Training Fellowship (FS/15/80/31803) and Programme Grant (RG/18/12/34040).
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Affiliation(s)
- M A Peterzan
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - W T Clarke
- University of Oxford, Oxford, United Kingdom
| | - C A Lygate
- University of Oxford, Oxford, United Kingdom
| | - H A Lake
- University of Oxford, Oxford, United Kingdom
| | - J J Rayner
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - M J Hundertmark
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - A P Apps
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - R A Sayeed
- John Radcliffe Hospital, Oxford, United Kingdom
| | - M Petrou
- John Radcliffe Hospital, Oxford, United Kingdom
| | | | | | - S Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - C T Rodgers
- University of Cambridge, Wolfson Brain Imaging Centre, Cambridge, United Kingdom
| | - O J Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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Whittington HJ, Ostrowski PJ, McAndrew DJ, Cao F, Shaw A, Eykyn TR, Lake HA, Tyler J, Schneider JE, Neubauer S, Zervou S, Lygate CA. Over-expression of mitochondrial creatine kinase in the murine heart improves functional recovery and protects against injury following ischaemia-reperfusion. Cardiovasc Res 2019; 114:858-869. [PMID: 29509881 PMCID: PMC5909653 DOI: 10.1093/cvr/cvy054] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 03/01/2018] [Indexed: 12/25/2022] Open
Abstract
Aims Mitochondrial creatine kinase (MtCK) couples ATP production via oxidative phosphorylation to phosphocreatine in the cytosol, which acts as a mobile energy store available for regeneration of ATP at times of high demand. We hypothesized that elevating MtCK would be beneficial in ischaemia-reperfusion (I/R) injury. Methods and results Mice were created over-expressing the sarcomeric MtCK gene with αMHC promoter at the Rosa26 locus (MtCK-OE) and compared with wild-type (WT) littermates. MtCK activity was 27% higher than WT, with no change in other CK isoenzymes or creatine levels. Electron microscopy confirmed normal mitochondrial cell density and mitochondrial localization of transgenic protein. Respiration in isolated mitochondria was unaltered and metabolomic analysis by 1 H-NMR suggests that cellular metabolism was not grossly affected by transgene expression. There were no significant differences in cardiac structure or function under baseline conditions by cine-MRI or LV haemodynamics. In Langendorff-perfused hearts subjected to 20 min ischaemia and 30 min reperfusion, MtCK-OE exhibited less ischaemic contracture, and improved functional recovery (Rate pressure product 58% above WT; P < 0.001). These hearts had reduced myocardial infarct size, which was confirmed in vivo: 55 ± 4% in WT vs. 29 ± 4% in MtCK-OE; P < 0.0001). Isolated cardiomyocytes from MtCK-OE hearts exhibited delayed opening of the mitochondrial permeability transition pore (mPTP) compared to WT, which was confirmed by reduced mitochondrial swelling in response to calcium. There was no detectable change in the structural integrity of the mitochondrial membrane. Conclusions Modest elevation of MtCK activity in the heart does not adversely affect cellular metabolism, mitochondrial or in vivo cardiac function, but modifies mPTP opening to protect against I/R injury and improve functional recovery. Our findings support MtCK as a prime therapeutic target in myocardial ischaemia.
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Affiliation(s)
- Hannah J Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Philip J Ostrowski
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Fang Cao
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Andrew Shaw
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Thomas R Eykyn
- School of Biomedical Engineering and Imaging Sciences, King's College London, King's Health Partners, St Thomas' Hospital, London, UK
| | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jack Tyler
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jurgen E Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.,Experimental and Preclinical Imaging Centre (ePIC), Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, The Wellcome Centre for Human Genetics, and the BHF Centre of Research Excellence, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
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Faller KME, Atzler D, McAndrew DJ, Zervou S, Whittington HJ, Simon JN, Aksentijevic D, Ten Hove M, Choe CU, Isbrandt D, Casadei B, Schneider JE, Neubauer S, Lygate CA. Impaired cardiac contractile function in arginine:glycine amidinotransferase knockout mice devoid of creatine is rescued by homoarginine but not creatine. Cardiovasc Res 2019; 114:417-430. [PMID: 29236952 PMCID: PMC5982714 DOI: 10.1093/cvr/cvx242] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 12/08/2017] [Indexed: 01/09/2023] Open
Abstract
Aims Creatine buffers cellular adenosine triphosphate (ATP) via the creatine kinase reaction. Creatine levels are reduced in heart failure, but their contribution to pathophysiology is unclear. Arginine:glycine amidinotransferase (AGAT) in the kidney catalyses both the first step in creatine biosynthesis as well as homoarginine (HA) synthesis. AGAT-/- mice fed a creatine-free diet have a whole body creatine-deficiency. We hypothesized that AGAT-/- mice would develop cardiac dysfunction and rescue by dietary creatine would imply causality. Methods and results Withdrawal of dietary creatine in AGAT-/- mice provided an estimate of myocardial creatine efflux of ∼2.7%/day; however, in vivo cardiac function was maintained despite low levels of myocardial creatine. Using AGAT-/- mice naïve to dietary creatine we confirmed absence of phosphocreatine in the heart, but crucially, ATP levels were unchanged. Potential compensatory adaptations were absent, AMPK was not activated and respiration in isolated mitochondria was normal. AGAT-/- mice had rescuable changes in body water and organ weights suggesting a role for creatine as a compatible osmolyte. Creatine-naïve AGAT-/- mice had haemodynamic impairment with low LV systolic pressure and reduced inotropy, lusitropy, and contractile reserve. Creatine supplementation only corrected systolic pressure despite normalization of myocardial creatine. AGAT-/- mice had low plasma HA and supplementation completely rescued all other haemodynamic parameters. Contractile dysfunction in AGAT-/- was confirmed in Langendorff perfused hearts and in creatine-replete isolated cardiomyocytes, indicating that HA is necessary for normal cardiac function. Conclusions Our findings argue against low myocardial creatine per se as a major contributor to cardiac dysfunction. Conversely, we show that HA deficiency can impair cardiac function, which may explain why low HA is an independent risk factor for multiple cardiovascular diseases.
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Affiliation(s)
- Kiterie M E Faller
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Dorothee Atzler
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK.,German Centre for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Institute for Cardiovascular Prevention (IPEK), Pettenkoferstraße 8a & 9, 80336 Munich, Germany.,Walther-Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians University, Goethestrasse 33, 80336 Munich, Germany
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Hannah J Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jillian N Simon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Dunja Aksentijevic
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Michiel Ten Hove
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Chi-Un Choe
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Dirk Isbrandt
- Experimental Neurophysiology, German Center for Neurodegenerative Diseases (DZNE), 53175 Bonn, Germany.,The Institute for Molecular and Behavioral Neuroscience, University of Cologne, Kerpener Str. 62, 50937 Cologne, Germany
| | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Jurgen E Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK.,Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence at the University of Oxford and the Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford OX3 7BN, UK
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24
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Valli A, Morotti M, Zois CE, Albers PK, Soga T, Feldinger K, Fischer R, Frejno M, McIntyre A, Bridges E, Haider S, Buffa FM, Baban D, Rodriguez M, Yanes O, Whittington HJ, Lake HA, Zervou S, Lygate CA, Kessler BM, Harris AL. Adaptation to HIF1α Deletion in Hypoxic Cancer Cells by Upregulation of GLUT14 and Creatine Metabolism. Mol Cancer Res 2019; 17:1531-1544. [PMID: 30885992 DOI: 10.1158/1541-7786.mcr-18-0315] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [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] [Received: 03/30/2018] [Revised: 01/28/2019] [Accepted: 03/13/2019] [Indexed: 12/12/2022]
Abstract
Hypoxia-inducible factor 1α is a key regulator of the hypoxia response in normal and cancer tissues. It is well recognized to regulate glycolysis and is a target for therapy. However, how tumor cells adapt to grow in the absence of HIF1α is poorly understood and an important concept to understand for developing targeted therapies is the flexibility of the metabolic response to hypoxia via alternative pathways. We analyzed pathways that allow cells to survive hypoxic stress in the absence of HIF1α, using the HCT116 colon cancer cell line with deleted HIF1α versus control. Spheroids were used to provide a 3D model of metabolic gradients. We conducted a metabolomic, transcriptomic, and proteomic analysis and integrated the results. These showed surprisingly that in three-dimensional growth, a key regulatory step of glycolysis is Aldolase A rather than phosphofructokinase. Furthermore, glucose uptake could be maintained in hypoxia through upregulation of GLUT14, not previously recognized in this role. Finally, there was a marked adaptation and change of phosphocreatine energy pathways, which made the cells susceptible to inhibition of creatine metabolism in hypoxic conditions. Overall, our studies show a complex adaptation to hypoxia that can bypass HIF1α, but it is targetable and it provides new insight into the key metabolic pathways involved in cancer growth. IMPLICATIONS: Under hypoxia and HIF1 blockade, cancer cells adapt their energy metabolism via upregulation of the GLUT14 glucose transporter and creatine metabolism providing new avenues for drug targeting.
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Affiliation(s)
- Alessandro Valli
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Matteo Morotti
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Christos E Zois
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Patrick K Albers
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Tomoyoshi Soga
- Institute for Advanced Biosciences, Keio University, Tsuruoka, Yamagata, Japan
| | - Katharina Feldinger
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Roman Fischer
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Martin Frejno
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Alan McIntyre
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Esther Bridges
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Syed Haider
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Francesca M Buffa
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Dilair Baban
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Miguel Rodriguez
- Metabolomics Platform, IISPV, Department of Electronic Engineering, Universitat Rovira i Virgili, Tarragona, Spain
- Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders-CIBERDEM, Madrid, Spain
| | - Oscar Yanes
- Metabolomics Platform, IISPV, Department of Electronic Engineering, Universitat Rovira i Virgili, Tarragona, Spain
- Spanish Biomedical Research Center in Diabetes and Associated Metabolic Disorders-CIBERDEM, Madrid, Spain
| | - Hannah J Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Benedikt M Kessler
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Adrian L Harris
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
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25
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Affiliation(s)
- Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Oxford, OX3 7BN, UK
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26
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Clarke WT, Peterzan MA, Rayner JJ, Sayeed RA, Petrou M, Krasopoulos G, Lake HA, Raman B, Watson WD, Cox P, Hundertmark MJ, Apps AP, Lygate CA, Neubauer S, Rider OJ, Rodgers CT. Localized rest and stress human cardiac creatine kinase reaction kinetics at 3 T. NMR Biomed 2019; 32:e4085. [PMID: 30920054 PMCID: PMC6542687 DOI: 10.1002/nbm.4085] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/24/2019] [Accepted: 01/28/2019] [Indexed: 05/11/2023]
Abstract
Changes in the kinetics of the creatine kinase (CK) shuttle are sensitive markers of cardiac energetics but are typically measured at rest and in the prone position. This study aims to measure CK kinetics during pharmacological stress at 3 T, with measurement in the supine position. A shorter "stressed saturation transfer" (StreST) extension to the triple repetition time saturation transfer (TRiST) method is proposed. We assess scanning in a supine position and validate the MR measurement against biopsy assay of CK activity. We report normal ranges of stress CK forward rate (kfCK ) for healthy volunteers and obese patients. TRiST measures kfCK in 40 min at 3 T. StreST extends the previously developed TRiST to also make a further kfCK measurement during <20 min of dobutamine stress. We test our TRiST implementation in skeletal muscle and myocardium in both prone and supine positions. We evaluate StreST in the myocardium of six healthy volunteers and 34 obese subjects. We validated MR-measured kfCK against biopsy assays of CK activity. TRiST kfCK values matched literature values in skeletal muscle (kfCK = 0.25 ± 0.03 s-1 vs 0.27 ± 0.03 s-1 ) and myocardium when measured in the prone position (0.32 ± 0.15 s-1 ), but a significant difference was found for TRiST kfCK measured supine (0.24 ± 0.12 s-1 ). This difference was because of different respiratory- and cardiac-motion-induced B0 changes in the two positions. Using supine TRiST, cardiac kfCK values for normal-weight subjects were 0.15 ± 0.09 s-1 at rest and 0.17 ± 0.15 s-1 during stress. For obese subjects, kfCK was 0.16 ± 0.07 s-1 at rest and 0.17 ± 0.10 s-1 during stress. Rest myocardial kfCK and CK activity from LV biopsies of the same subjects correlated (R = 0.43, p = 0.03). We present an independent implementation of TRiST on the Siemens platform using a commercially available coil. Our extended StreST protocol enables cardiac kfCK to be measured during dobutamine-induced stress in the supine position.
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Affiliation(s)
- William T. Clarke
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
- Wellcome Centre for Integrative Neuroimaging, FMRIBUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Mark A. Peterzan
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Jennifer J. Rayner
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Rana A. Sayeed
- Department of Cardiothoracic Surgery, John Radcliffe HospitalOxford University Hospitals NHS Foundation TrustOxfordUK
| | - Mario Petrou
- Department of Cardiothoracic Surgery, John Radcliffe HospitalOxford University Hospitals NHS Foundation TrustOxfordUK
| | - George Krasopoulos
- Department of Cardiothoracic Surgery, John Radcliffe HospitalOxford University Hospitals NHS Foundation TrustOxfordUK
| | - Hannah A. Lake
- Department of Cardiovascular MedicineUniversity of Oxford, Wellcome Trust Centre for Human GeneticsRoosevelt DriveOxfordUK
| | - Betty Raman
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - William D. Watson
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Pete Cox
- Department of Physiology AnatomyUniversity of OxfordParks Road, Sherrington BuildingOxfordUK
| | - Moritz J. Hundertmark
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Andrew P. Apps
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Craig A. Lygate
- Department of Cardiovascular MedicineUniversity of Oxford, Wellcome Trust Centre for Human GeneticsRoosevelt DriveOxfordUK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Oliver J. Rider
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
| | - Christopher T. Rodgers
- Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Division of Cardiovascular Medicine RDMUniversity of Oxford, John Radcliffe HospitalOxfordUK
- Wolfson Brain Imaging CentreUniversity of CambridgeBox 65, Cambridge Biomedical CampusCambridgeUK
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27
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Peterzan MA, Lygate CA, Lake HA, Rayner JJ, Hundertmark MJ, Apps AP, Neubauer S, Clarke WT, Rodgers CT, Rider OJ. P5449ATP delivery rate is maintained in severe aortic stenosis with preserved systolic function despite reduced PCr/ATP ratio. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.p5449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- M A Peterzan
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - C A Lygate
- University of Oxford, Oxford, United Kingdom
| | - H A Lake
- University of Oxford, Oxford, United Kingdom
| | - J J Rayner
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - M J Hundertmark
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - A P Apps
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - S Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - W T Clarke
- University of Oxford, Oxford, United Kingdom
| | - C T Rodgers
- University of Cambridge, Wolfson Brain Imaging Centre, Cambridge, United Kingdom
| | - O J Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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28
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Peterzan MA, Lygate CA, Lake HA, Rayner JJ, Hundertmark MJ, Apps AP, Sayeed RA, Petrou M, Krasopoulos G, Neubauer S, Clarke WT, Rodgers CT, Rider OJ. 6161Reduced myocardial ATP delivery in severe primary mitral regurgitation: a novel marker to guide timing of surgery? Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy566.6161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- M A Peterzan
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - C A Lygate
- University of Oxford, Oxford, United Kingdom
| | - H A Lake
- University of Oxford, Oxford, United Kingdom
| | - J J Rayner
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - M J Hundertmark
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - A P Apps
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - R A Sayeed
- John Radcliffe Hospital, Oxford, United Kingdom
| | - M Petrou
- John Radcliffe Hospital, Oxford, United Kingdom
| | | | - S Neubauer
- John Radcliffe Hospital, Oxford, United Kingdom
| | - W T Clarke
- University of Oxford, Oxford, United Kingdom
| | - C T Rodgers
- University of Cambridge, Wolfson Brain Imaging Centre, Cambridge, United Kingdom
| | - O J Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom
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29
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Chuaiphichai S, Rashbrook VS, Hale AB, Trelfa L, Patel J, McNeill E, Lygate CA, Channon KM, Douglas G. Endothelial Cell Tetrahydrobiopterin Modulates Sensitivity to Ang (Angiotensin) II-Induced Vascular Remodeling, Blood Pressure, and Abdominal Aortic Aneurysm. Hypertension 2018; 72:128-138. [PMID: 29844152 PMCID: PMC6012043 DOI: 10.1161/hypertensionaha.118.11144] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 04/04/2018] [Accepted: 04/10/2018] [Indexed: 12/30/2022]
Abstract
GTPCH (GTP cyclohydrolase 1, encoded by Gch1) is required for the synthesis of tetrahydrobiopterin; a critical regulator of endothelial NO synthase function. We have previously shown that mice with selective loss of Gch1 in endothelial cells have mild vascular dysfunction, but the consequences of endothelial cell tetrahydrobiopterin deficiency in vascular disease pathogenesis are unknown. We investigated the pathological consequence of Ang (angiotensin) II infusion in endothelial cell Gch1 deficient (Gch1fl/fl Tie2cre) mice. Ang II (0.4 mg/kg per day, delivered by osmotic minipump) caused a significant decrease in circulating tetrahydrobiopterin levels in Gch1fl/fl Tie2cre mice and a significant increase in the Nω-nitro-L-arginine methyl ester inhabitable production of H2O2 in the aorta. Chronic treatment with this subpressor dose of Ang II resulted in a significant increase in blood pressure only in Gch1fl/fl Tie2cre mice. This finding was mirrored with acute administration of Ang II, where increased sensitivity to Ang II was observed at both pressor and subpressor doses. Chronic Ang II infusion in Gch1fl/fl Tie2ce mice resulted in vascular dysfunction in resistance mesenteric arteries with an enhanced constrictor and decreased dilator response and medial hypertrophy. Altered vascular remodeling was also observed in the aorta with an increase in the incidence of abdominal aortic aneurysm formation in Gch1fl/fl Tie2ce mice. These findings indicate a specific requirement for endothelial cell tetrahydrobiopterin in modulating the hemodynamic and structural changes induced by Ang II, through modulation of blood pressure, structural changes in resistance vessels, and aneurysm formation in the aorta.
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Affiliation(s)
- Surawee Chuaiphichai
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Victoria S Rashbrook
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Ashley B Hale
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Lucy Trelfa
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Jyoti Patel
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Eileen McNeill
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Craig A Lygate
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
| | - Keith M Channon
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom.
| | - Gillian Douglas
- From the Division of Cardiovascular Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, United Kingdom
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30
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Stockebrand M, Sasani A, Das D, Hornig S, Hermans-Borgmeyer I, Lake HA, Isbrandt D, Lygate CA, Heerschap A, Neu A, Choe CU. A Mouse Model of Creatine Transporter Deficiency Reveals Impaired Motor Function and Muscle Energy Metabolism. Front Physiol 2018; 9:773. [PMID: 30013483 PMCID: PMC6036259 DOI: 10.3389/fphys.2018.00773] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [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: 03/26/2018] [Accepted: 06/04/2018] [Indexed: 11/22/2022] Open
Abstract
Creatine serves as fast energy buffer in organs of high-energy demand such as brain and skeletal muscle. L-Arginine:glycine amidinotransferase (AGAT) and guanidinoacetate N-methyltransferase are responsible for endogenous creatine synthesis. Subsequent uptake into target organs like skeletal muscle, heart and brain is mediated by the creatine transporter (CT1, SLC6A8). Creatine deficiency syndromes are caused by defects of endogenous creatine synthesis or transport and are mainly characterized by intellectual disability, behavioral abnormalities, poorly developed muscle mass, and in some cases also muscle weakness. CT1-deficiency is estimated to be among the most common causes of X-linked intellectual disability and therefore the brain phenotype was the main focus of recent research. Unfortunately, very limited data concerning muscle creatine levels and functions are available from patients with CT1 deficiency. Furthermore, different CT1-deficient mouse models yielded conflicting results and detailed analyses of their muscular phenotype are lacking. Here, we report the generation of a novel CT1-deficient mouse model and characterized the effects of creatine depletion in skeletal muscle. HPLC-analysis showed strongly reduced total creatine levels in skeletal muscle and heart. MR-spectroscopy revealed an almost complete absence of phosphocreatine in skeletal muscle. Increased AGAT expression in skeletal muscle was not sufficient to compensate for insufficient creatine transport. CT1-deficient mice displayed profound impairment of skeletal muscle function and morphology (i.e., reduced strength, reduced endurance, and muscle atrophy). Furthermore, severely altered energy homeostasis was evident on magnetic resonance spectroscopy. Strongly reduced phosphocreatine resulted in decreased ATP/Pi levels despite an increased inorganic phosphate to ATP flux. Concerning glucose metabolism, we show increased glucose transporter type 4 expression in muscle and improved glucose clearance in CT1-deficient mice. These metabolic changes were associated with activation of AMP-activated protein kinase – a central regulator of energy homeostasis. In summary, creatine transporter deficiency resulted in a severe muscle weakness and atrophy despite different compensatory mechanisms.
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Affiliation(s)
- Malte Stockebrand
- German Center for Neurodegenerative Diseases, Bonn, Germany.,Institute for Molecular and Behavioral Neuroscience, University of Cologne, Cologne, Germany
| | - Ali Sasani
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Experimental Neuropediatrics, Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Devashish Das
- Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Sönke Hornig
- Experimental Neuropediatrics, Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Irm Hermans-Borgmeyer
- Transgenic Mouse Unit, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Hannah A Lake
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence, University of Oxford, Oxford, United Kingdom.,Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Dirk Isbrandt
- German Center for Neurodegenerative Diseases, Bonn, Germany
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, BHF Centre of Research Excellence, University of Oxford, Oxford, United Kingdom.,Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Arend Heerschap
- Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen, Netherlands
| | - Axel Neu
- Experimental Neuropediatrics, Department of Pediatrics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Chi-Un Choe
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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31
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Chuaiphichai S, Rashbrook VS, Hale AB, Trelfa L, Mcneill E, Lygate CA, Channon KM, Douglas G. P350Deficiency in endothelial cell tetrahydrobiopterin increases resistance vascular remodelling, blood pressure, and susceptibility to aortic abdominal aneurysm in response to angiotensin II. Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- S Chuaiphichai
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - V S Rashbrook
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - A B Hale
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - L Trelfa
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - E Mcneill
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - C A Lygate
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - K M Channon
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
| | - G Douglas
- University of Oxford, Cardiovascular Medicine, Oxford, United Kingdom
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32
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Abstract
The energy starvation hypothesis proposes that maladaptive metabolic remodeling antedates, initiates, and maintains adverse contractile dysfunction in heart failure (HF). Better understanding of the cardiac metabolic phenotype and metabolic signaling could help identify the role metabolic remodeling plays within HF and the conditions known to transition toward HF, including "pathological" hypertrophy. In this review, we discuss metabolic phenotype and metabolic signaling in the contexts of pathological hypertrophy and HF. We discuss the significance of alterations in energy supply (substrate utilization, oxidative capacity, and phosphotransfer) and energy sensing using observations from human and animal disease models and models of manipulated energy supply/sensing. We aim to provide ways of thinking about metabolic remodeling that center around metabolic flexibility, capacity (reserve), and efficiency rather than around particular substrate preferences or transcriptomic profiles. We show that maladaptive metabolic remodeling takes multiple forms across multiple energy-handling domains. We suggest that lack of metabolic flexibility and reserve (substrate, oxidative, and phosphotransfer) represents a final common denominator ultimately compromising efficiency and contractile reserve in stressful contexts.
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Affiliation(s)
- Mark A Peterzan
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - Oliver J Rider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
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Zervou S, Whittington HJ, Ostrowski PJ, Cao F, Tyler J, Lake HA, Neubauer S, Lygate CA. 222 Augmentation of creatine kinase in vitro protects against simulated ischaemia reperfusion injury. Heart 2017. [DOI: 10.1136/heartjnl-2017-311726.220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Teh I, McClymont D, Zdora MC, Whittington HJ, Davidoiu V, Lee J, Lygate CA, Rau C, Zanette I, Schneider JE. Validation of diffusion tensor MRI measurements of cardiac microstructure with structure tensor synchrotron radiation imaging. J Cardiovasc Magn Reson 2017; 19:31. [PMID: 28279178 PMCID: PMC5345150 DOI: 10.1186/s12968-017-0342-x] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 02/16/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Diffusion tensor imaging (DTI) is widely used to assess tissue microstructure non-invasively. Cardiac DTI enables inference of cell and sheetlet orientations, which are altered under pathological conditions. However, DTI is affected by many factors, therefore robust validation is critical. Existing histological validation is intrinsically flawed, since it requires further tissue processing leading to sample distortion, is routinely limited in field-of-view and requires reconstruction of three-dimensional volumes from two-dimensional images. In contrast, synchrotron radiation imaging (SRI) data enables imaging of the heart in 3D without further preparation following DTI. The objective of the study was to validate DTI measurements based on structure tensor analysis of SRI data. METHODS One isolated, fixed rat heart was imaged ex vivo with DTI and X-ray phase contrast SRI, and reconstructed at 100 μm and 3.6 μm isotropic resolution respectively. Structure tensors were determined from the SRI data and registered to the DTI data. RESULTS Excellent agreement in helix angles (HA) and transverse angles (TA) was observed between the DTI and structure tensor synchrotron radiation imaging (STSRI) data, where HADTI-STSRI = -1.4° ± 23.2° and TADTI-STSRI = -1.4° ± 35.0° (mean ± 1.96 standard deviation across all voxels in the left ventricle). STSRI confirmed that the primary eigenvector of the diffusion tensor corresponds with the cardiomyocyte long-axis across the whole myocardium. CONCLUSIONS We have used STSRI as a novel and high-resolution gold standard for the validation of DTI, allowing like-with-like comparison of three-dimensional tissue structures in the same intact heart free of distortion. This represents a critical step forward in independently verifying the structural basis and informing the interpretation of cardiac DTI data, thereby supporting the further development and adoption of DTI in structure-based electro-mechanical modelling and routine clinical applications.
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Affiliation(s)
- Irvin Teh
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK
| | - Darryl McClymont
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Marie-Christine Zdora
- Diamond Light Source, Didcot, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Hannah J. Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Valentina Davidoiu
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Jack Lee
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Christoph Rau
- Diamond Light Source, Didcot, UK
- University of Manchester, Manchester, UK
- Feinberg School of Medicine, Northwestern University, Chicago, USA
| | | | - Jürgen E. Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
- Leeds Institute of Cardiovascular & Metabolic Medicine, University of Leeds, Leeds, UK
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Carnicer R, Suffredini S, Liu X, Reilly S, Simon JN, Surdo NC, Zhang YH, Lygate CA, Channon KM, Casadei B. The Subcellular Localisation of Neuronal Nitric Oxide Synthase Determines the Downstream Effects of NO on Myocardial Function. Cardiovasc Res 2017; 113:321-331. [PMID: 28158509 PMCID: PMC5408949 DOI: 10.1093/cvr/cvx002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 10/14/2016] [Accepted: 11/26/2016] [Indexed: 01/12/2023] Open
Abstract
Aims In healthy hearts, the neuronal nitric oxide synthase (nNOS) is predominantly localized to the sarcoplasmic reticulum (SR), where it regulates the ryanodine receptor Ca2+ release channel (RyR2) and phospholamban (PLB) phosphorylation, and to a lesser extent to the sarcolemmal membrane where it inhibits the L-type Ca2+ current (I Ca). However, in failing hearts, impaired relaxation and depressed inotropy are associated with a larger proportion of nNOS being localized to the sarcolemmal membrane. Whether there is a causal relationship between altered myocardial function and subcellular localization of nNOS remains to be assessed. Methods and results Adenoviruses (AdV) encoding for a human nNOS.eGFP fusion protein or eGFP were injected into the left ventricle (LV) of nNOS−/− mice. nNOS.eGFP localized to the sarcolemmal and t-tubular membrane and immunoprecipitated with syntrophin and caveolin-3 but not with RyR2. Myocardial transduction of nNOS.eGFP resulted in a significantly increased NOS activity (10-fold, P < 0.01), a 20% increase in myocardial tetrahydrobiopterin (BH4) (P < 0.05), and a 30% reduction in superoxide production (P < 0.001). LV myocytes transduced with nNOS.eGFP showed a significantly lower basal and β-adrenergic stimulated I Ca, [Ca2+]i transient amplitude and cell shortening (vs. eGFP). All differences between groups were abolished after NOS inhibition. In contrast, nNOS.eGFP had no effect on RyR nitrosylation, PLB phosphorylation or the rate of myocardial relaxation and [Ca2+]i decay. Conclusion Our findings indicate that nNOS-mediated regulation of myocardial excitation–contraction (E–C) coupling is exquisitely dependent on nNOS subcellular localization and suggests a partially adaptive role for sarcolemmal nNOS in the human failing myocardium.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, L6 West Wing, John Radcliffe Hospital, Headley Way, Headington, Oxford. OX3 9DU, UK
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Atzler D, McAndrew DJ, Cordts K, Schneider JE, Zervou S, Schwedhelm E, Neubauer S, Lygate CA. Dietary Supplementation with Homoarginine Preserves Cardiac Function in a Murine Model of Post-Myocardial Infarction Heart Failure. Circulation 2017; 135:400-402. [DOI: 10.1161/circulationaha.116.025673] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Dorothee Atzler
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Debra J. McAndrew
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Kathrin Cordts
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Jürgen E. Schneider
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Sevasti Zervou
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Edzard Schwedhelm
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Stefan Neubauer
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
| | - Craig A. Lygate
- From Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK (D.A., D.J.M., J.E.S., S.Z., S.N., C.A.L.); Division of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig Maximilians-University Munich, Germany (D.A.); Institute for Cardiovascular Prevention, Ludwig-Maximilians-University Munich, Deutsches Zentrum füz-Kreislauf-Forschung e.V., partner site Munich Heart Alliance, Germany (D.A.); Department of Clinical Pharmacology and Toxicology,
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Smart N, Riegler J, Turtle CW, Lygate CA, McAndrew DJ, Gehmlich K, Dubé KN, Price AN, Muthurangu V, Taylor AM, Lythgoe MF, Redwood C, Riley PR. Aberrant developmental titin splicing and dysregulated sarcomere length in Thymosin β4 knockout mice. J Mol Cell Cardiol 2017; 102:94-107. [PMID: 27914791 PMCID: PMC5319848 DOI: 10.1016/j.yjmcc.2016.10.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 10/20/2016] [Accepted: 10/22/2016] [Indexed: 02/07/2023]
Abstract
Sarcomere assembly is a highly orchestrated and dynamic process which adapts, during perinatal development, to accommodate growth of the heart. Sarcomeric components, including titin, undergo an isoform transition to adjust ventricular filling. Many sarcomeric genes have been implicated in congenital cardiomyopathies, such that understanding developmental sarcomere transitions will inform the aetiology and treatment. We sought to determine whether Thymosin β4 (Tβ4), a peptide that regulates the availability of actin monomers for polymerization in non-muscle cells, plays a role in sarcomere assembly during cardiac morphogenesis and influences adult cardiac function. In Tβ4 null mice, immunofluorescence-based sarcomere analyses revealed shortened thin filament, sarcomere and titin spring length in cardiomyocytes, associated with precocious up-regulation of the short titin isoforms during the postnatal splicing transition. By magnetic resonance imaging, this manifested as diminished stroke volume and limited contractile reserve in adult mice. Extrapolating to an in vitro cardiomyocyte model, the altered postnatal splicing was corrected with addition of synthetic Tβ4, whereby normal sarcomere length was restored. Our data suggest that Tβ4 is required for setting correct sarcomere length and for appropriate splicing of titin, not only in the heart but also in skeletal muscle. Distinguishing between thin filament extension and titin splicing as the primary defect is challenging, as these events are intimately linked. The regulation of titin splicing is a previously unrecognised role of Tβ4 and gives preliminary insight into a mechanism by which titin isoforms may be manipulated to correct cardiac dysfunction.
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Affiliation(s)
- Nicola Smart
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
| | - Johannes Riegler
- Centre for Advanced Biomedical Imaging, Department of Medicine, University College London (UCL), London, UK
| | - Cameron W Turtle
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Katja Gehmlich
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | | | - Anthony N Price
- Centre for Advanced Biomedical Imaging, Department of Medicine, University College London (UCL), London, UK
| | - Vivek Muthurangu
- Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, London, UK
| | - Andrew M Taylor
- Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, London, UK
| | - Mark F Lythgoe
- Centre for Advanced Biomedical Imaging, Department of Medicine, University College London (UCL), London, UK
| | - Charles Redwood
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Paul R Riley
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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Zak J, Vives V, Szumska D, Vernet A, Schneider JE, Miller P, Slee EA, Joss S, Lacassie Y, Chen E, Escobar LF, Tucker M, Aylsworth AS, Dubbs HA, Collins AT, Andrieux J, Dieux-Coeslier A, Haberlandt E, Kotzot D, Scott DA, Parker MJ, Zakaria Z, Choy YS, Wieczorek D, Innes AM, Jun KR, Zinner S, Prin F, Lygate CA, Pretorius P, Rosenfeld JA, Mohun TJ, Lu X. ASPP2 deficiency causes features of 1q41q42 microdeletion syndrome. Cell Death Differ 2016; 23:1973-1984. [PMID: 27447114 PMCID: PMC5136487 DOI: 10.1038/cdd.2016.76] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [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] [Received: 04/04/2016] [Revised: 06/09/2016] [Accepted: 06/13/2016] [Indexed: 11/09/2022] Open
Abstract
Chromosomal abnormalities are implicated in a substantial number of human developmental syndromes, but for many such disorders little is known about the causative genes. The recently described 1q41q42 microdeletion syndrome is characterized by characteristic dysmorphic features, intellectual disability and brain morphological abnormalities, but the precise genetic basis for these abnormalities remains unknown. Here, our detailed analysis of the genetic abnormalities of 1q41q42 microdeletion cases identified TP53BP2, which encodes apoptosis-stimulating protein of p53 2 (ASPP2), as a candidate gene for brain abnormalities. Consistent with this, Trp53bp2-deficient mice show dilation of lateral ventricles resembling the phenotype of 1q41q42 microdeletion patients. Trp53bp2 deficiency causes 100% neonatal lethality in the C57BL/6 background associated with a high incidence of neural tube defects and a range of developmental abnormalities such as congenital heart defects, coloboma, microphthalmia, urogenital and craniofacial abnormalities. Interestingly, abnormalities show a high degree of overlap with 1q41q42 microdeletion-associated abnormalities. These findings identify TP53BP2 as a strong candidate causative gene for central nervous system (CNS) defects in 1q41q42 microdeletion syndrome, and open new avenues for investigation of the mechanisms underlying CNS abnormalities.
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Affiliation(s)
- J Zak
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - V Vives
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - D Szumska
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - A Vernet
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - J E Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - P Miller
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - E A Slee
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
| | - S Joss
- Queen Elizabeth University Hospital Glasgow, Glasgow G51 4TF, UK
| | - Y Lacassie
- Department of Pediatrics, Louisiana State University, New Orleans, LA 70118, USA
- Genetics Services, Children's Hospital New Orleans, New Orleans, LA 70118, USA
| | - E Chen
- Kaiser Permanente, San Francisco Medical Center, San Francisco, CA 94115, USA
| | - L F Escobar
- St Vincent Children's Hospital, Indianapolis, IN 46260, USA
| | - M Tucker
- St Vincent Children's Hospital, Indianapolis, IN 46260, USA
| | - A S Aylsworth
- Departments of Pediatrics and Genetics, University of North Carolina, Chapel Hill, NC 27599, USA
| | - H A Dubbs
- Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - A T Collins
- Seattle Children's Hospital, Seattle, WA 98105, USA
| | - J Andrieux
- Institute of Medical Genetics, Jeanne de Flandre Hospital, CHRU de Lille, Lille 59000, France
| | | | - E Haberlandt
- Clinical Department of Pediatrics, Innsbruck Medical University, Innsbruck A-6020, Austria
| | - D Kotzot
- Division of Human Genetics, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck A-6020, Austria
| | - D A Scott
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - M J Parker
- Sheffield Children's Hospital NHS Foundation Trust, Western Bank, Sheffield, S10 2TH, UK
| | - Z Zakaria
- Institute for Medical Research, Kuala Lumpur, Jalan Pahang 50588, Malaysia
| | - Y S Choy
- Prince Court Medical Centre, Kuala Lumpur 50450, Malaysia
| | - D Wieczorek
- Institute of Human Genetics, University Clinic Essen, Duisburg-Essen University, Essen 45122, Germany
- Institute of Human Genetics, University Clinic, Heinrich-Heine University, Düsseldorf 40225, Germany
| | - A M Innes
- Department of Medical Genetics and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada T3B 6A8
| | - K R Jun
- Department of Laboratory Medicine, Haeundae Paik Hospital, Inje University, Haeundae-gu, Busan, Korea
| | - S Zinner
- Seattle Children's Hospital, Seattle, WA 98105, USA
| | - F Prin
- The Francis Crick Institute Mill Hill Laboratory, London NW7 1AA, UK
| | - C A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - P Pretorius
- Department of Neuroradiology, John Radcliffe Hospital, Oxford University Hospitals NHS Trust, Oxford OX3 9DU, UK
| | - J A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - T J Mohun
- The Francis Crick Institute Mill Hill Laboratory, London NW7 1AA, UK
| | - X Lu
- Ludwig Institute for Cancer Research, Nuffield Department of Clinical Medicine, University of Oxford, Oxford OX3 7DQ, UK
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Abstract
Creatine is a principle component of the creatine kinase (CK) phosphagen system common to all vertebrates. It is found in excitable cells, such as cardiomyocytes, where it plays an important role in the buffering and transport of chemical energy to ensure that supply meets the dynamic demands of the heart. Multiple components of the CK system, including intracellular creatine levels, are reduced in heart failure, while ischaemia and hypoxia represent acute crises of energy provision. Elevation of myocardial creatine levels has therefore been suggested as potentially beneficial, however, achieving this goal is not trivial. This mini-review outlines the evidence in support of creatine elevation and critically examines the pharmacological approaches that are currently available. In particular, dietary creatine-supplementation does not sufficiently elevate creatine levels in the heart due to subsequent down-regulation of the plasma membrane creatine transporter (CrT). Attempts to increase passive diffusion and bypass the CrT, e.g. via creatine esters, have yet to be tested in the heart. However, studies in mice with genetic overexpression of the CrT demonstrate proof-of-principle that elevated creatine protects the heart from ischaemia-reperfusion injury. This suggests activation of the CrT as a major unmet pharmacological target. However, translation of this finding to the clinic will require a greater understanding of CrT regulation in health and disease and the development of small molecule activators.
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Affiliation(s)
| | | | | | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Wellcome Trust Centre for Human Genetics, Roosevelt Drive, Headington OX3 7BN, UK.
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40
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Teh I, McClymont D, Burton RAB, Maguire ML, Whittington HJ, Lygate CA, Kohl P, Schneider JE. Resolving Fine Cardiac Structures in Rats with High-Resolution Diffusion Tensor Imaging. Sci Rep 2016; 6:30573. [PMID: 27466029 PMCID: PMC4964346 DOI: 10.1038/srep30573] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [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] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 07/04/2016] [Indexed: 02/03/2023] Open
Abstract
Cardiac architecture is fundamental to cardiac function and can be assessed non-invasively with diffusion tensor imaging (DTI). Here, we aimed to overcome technical challenges in ex vivo DTI in order to extract fine anatomical details and to provide novel insights in the 3D structure of the heart. An integrated set of methods was implemented in ex vivo rat hearts, including dynamic receiver gain adjustment, gradient system scaling calibration, prospective adjustment of diffusion gradients, and interleaving of diffusion-weighted and non-diffusion-weighted scans. Together, these methods enhanced SNR and spatial resolution, minimised orientation bias in diffusion-weighting, and reduced temperature variation, enabling detection of tissue structures such as cell alignment in atria, valves and vessels at an unprecedented level of detail. Improved confidence in eigenvector reproducibility enabled tracking of myolaminar structures as a basis for segmentation of functional groups of cardiomyocytes. Ex vivo DTI facilitates acquisition of high quality structural data that complements readily available in vivo cardiac functional and anatomical MRI. The improvements presented here will facilitate next generation virtual models integrating micro-structural and electro-mechanical properties of the heart.
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Affiliation(s)
- Irvin Teh
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 7BN, United Kingdom
| | - Darryl McClymont
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 7BN, United Kingdom
| | - Rebecca A. B. Burton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, United Kingdom
| | - Mahon L. Maguire
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 7BN, United Kingdom
| | - Hannah J. Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 7BN, United Kingdom
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 7BN, United Kingdom
| | - Peter Kohl
- National Heart and Lung Institute, Imperial College London, London, SW3 6NP, United Kingdom
- Institute for Experimental Cardiovascular Medicine, University Heart Centre Freiburg · Bad Krozingen, Medical School of the University of Freiburg, Freiburg, 79110, Germany
| | - Jürgen E. Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 7BN, United Kingdom
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Zervou S, Yin X, Nabeebaccus AA, O’Brien BA, Cross RL, McAndrew DJ, Atkinson RA, Eykyn TR, Mayr M, Neubauer S, Lygate CA. Proteomic and metabolomic changes driven by elevating myocardial creatine suggest novel metabolic feedback mechanisms. Amino Acids 2016; 48:1969-81. [PMID: 27143170 PMCID: PMC4974297 DOI: 10.1007/s00726-016-2236-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 04/11/2016] [Indexed: 01/04/2023]
Abstract
Mice over-expressing the creatine transporter have elevated myocardial creatine levels [Cr] and are protected against ischaemia/reperfusion injury via improved energy reserve. However, mice with very high [Cr] develop cardiac hypertrophy and dysfunction. To investigate these contrasting effects, we applied a non-biased hypothesis-generating approach to quantify global protein and metabolite changes in the LV of mice stratified for [Cr] levels: wildtype, moderately elevated, and high [Cr] (65-85; 100-135; 160-250 nmol/mg protein, respectively). Male mice received an echocardiogram at 7 weeks of age with tissue harvested at 8 weeks. RV was used for [Cr] quantification by HPLC to select LV tissue for subsequent analysis. Two-dimensional difference in-gel electrophoresis identified differentially expressed proteins, which were manually picked and trypsin digested for nano-LC-MS/MS. Principal component analysis (PCA) showed efficient group separation (ANOVA P ≤ 0.05) and peptide sequences were identified by mouse database (UniProt 201203) using Mascot. A total of 27 unique proteins were found to be differentially expressed between normal and high [Cr], with proteins showing [Cr]-dependent differential expression, chosen for confirmation, e.g. α-crystallin B, a heat shock protein implicated in cardio-protection and myozenin-2, which could contribute to the hypertrophic phenotype. Nuclear magnetic resonance (¹H-NMR at 700 MHz) identified multiple strong correlations between [Cr] and key cardiac metabolites. For example, positive correlations with α-glucose (r² = 0.45; P = 0.002), acetyl-carnitine (r² = 0.50; P = 0.001), glutamine (r² = 0.59; P = 0.0002); and negative correlations with taurine (r² = 0.74; P < 0.0001), fumarate (r² = 0.45; P = 0.003), aspartate (r² = 0.59; P = 0.0002), alanine (r² = 0.66; P < 0.0001) and phosphocholine (r² = 0.60; P = 0.0002). These findings suggest wide-ranging and hitherto unexpected adaptations in substrate utilisation and energy metabolism with a general pattern of impaired energy generating pathways in mice with very high creatine levels.
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Affiliation(s)
- Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, and the BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Xiaoke Yin
- King’s British Heart Foundation Centre, King’s College London, London, UK
| | | | - Brett A. O’Brien
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Rebecca L. Cross
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, and the BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Debra J. McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, and the BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - R. Andrew Atkinson
- Randall Division of Cell and Molecular Biophysics, and the BHF Centre of Research Excellence, Centre for Biomolecular Spectroscopy, King’s College London, London, UK
| | - Thomas R. Eykyn
- Division of Imaging Sciences and Biomedical Engineering, King’s College London, London, UK
| | - Manuel Mayr
- King’s British Heart Foundation Centre, King’s College London, London, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, and the BHF Centre of Research Excellence, University of Oxford, Oxford, UK
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, and the BHF Centre of Research Excellence, University of Oxford, Oxford, UK
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Whittington HJ, McAndrew DJ, Cross RL, Neubauer S, Lygate CA. Protective Effect of Creatine Elevation against Ischaemia Reperfusion Injury Is Retained in the Presence of Co-Morbidities and during Cardioplegia. PLoS One 2016; 11:e0146429. [PMID: 26765737 PMCID: PMC4713158 DOI: 10.1371/journal.pone.0146429] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [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] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 12/15/2015] [Indexed: 11/18/2022] Open
Abstract
Aims Ischaemic heart disease is most prevalent in the ageing population and often exists with other comorbidities; however the majority of laboratory research uses young, healthy animal models. Several recent workshops and focus meetings have highlighted the importance of using clinically relevant models to help aid translation to realistic patient populations. We have previously shown that mice over-expressing the creatine transporter (CrT-OE) have elevated intracellular creatine levels and are protected against ischaemia-reperfusion injury. Here we test whether elevating intracellular creatine levels retains a cardioprotective effect in the presence of common comorbidities and whether it is additive to protection afforded by hypothermic cardioplegia. Methods and Results CrT-OE mice and wild-type controls were subjected to transverse aortic constriction for two weeks to induce compensated left ventricular hypertrophy (LVH). Hearts were retrogradely perfused in Langendorff mode for 15 minutes, followed by 20 minutes ischaemia and 30 minutes reperfusion. CrT-OE hearts exhibited significantly improved functional recovery (Rate pressure product) during reperfusion compared to WT littermates (76% of baseline vs. 59%, respectively, P = 0.02). Aged CrT-OE mouse hearts (78±5 weeks) also had enhanced recovery following 15 minutes ischaemia (104% of baseline vs. 67%, P = 0.0007). The cardioprotective effect of hypothermic high K+ cardioplegic arrest, as used during cardiac surgery and donor heart transplant, was further enhanced in prolonged ischaemia (90 minutes) in CrT-OE Langendorff perfused mouse hearts (76% of baseline vs. 55% of baseline as seen in WT hearts, P = 0.02). Conclusions These observations in clinically relevant models further support the development of modulators of intracellular creatine content as a translatable strategy for cardiac protection against ischaemia-reperfusion injury.
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Affiliation(s)
- Hannah J. Whittington
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine. Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Debra J. McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine. Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Rebecca L. Cross
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine. Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine. Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine. Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Maguire ML, Geethanath S, Lygate CA, Kodibagkar VD, Schneider JE. Compressed sensing to accelerate magnetic resonance spectroscopic imaging: evaluation and application to 23Na-imaging of mouse hearts. J Cardiovasc Magn Reson 2015; 17:45. [PMID: 26073300 PMCID: PMC4466859 DOI: 10.1186/s12968-015-0149-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 05/15/2015] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Magnetic Resonance Spectroscopic Imaging (MRSI) has wide applicability for non-invasive biochemical assessment in clinical and pre-clinical applications but suffers from long scan times. Compressed sensing (CS) has been successfully applied to clinical 1H MRSI, however a detailed evaluation of CS for conventional chemical shift imaging is lacking. Here we evaluate the performance of CS accelerated MRSI, and specifically apply it to accelerate 23Na-MRSI on mouse hearts in vivo at 9.4 T. METHODS Synthetic phantom data representing a simplified section across a mouse thorax were used to evaluate the fidelity of the CS reconstruction for varying levels of under-sampling, resolution and signal-to-noise ratios (SNR). The amplitude of signals arising from within a compartment, and signal contamination arising from outside the compartment relative to noise-free Fourier-transformed (FT) data were determined. Simulation results were subsequently verified experimentally in phantoms and in three mouse hearts in vivo. RESULTS CS reconstructed MRSI data are scaled linearly relative to absolute signal intensities from the fully-sampled FT reconstructed case (R(2) > 0.8, p-value < 0.001). Higher acceleration factors resulted in a denoising of the reconstructed spectra, but also in an increased blurring of compartment boundaries, particularly at lower spatial resolutions. Increasing resolution and SNR decreased cross-compartment contamination and yielded signal amplitudes closer to the FT data. Proof-of-concept high-resolution, 3-fold accelerated 23Na-amplitude maps of murine myocardium could be obtained within ~23 mins. CONCLUSIONS Relative signal amplitudes (i.e. metabolite ratios) and absolute quantification of metabolite concentrations can be accurately determined with up to 5-fold under-sampled, CS-reconstructed MRSI. Although this work focused on murine cardiac 23Na-MRSI, the results are equally applicable to other nuclei and tissues (e.g., 1H MRSI in brain). Significant reduction in MRSI scan time will reduce the burden on the subject, increase scanner throughput, and may open new avenues for (pre-) clinical metabolic studies.
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Affiliation(s)
- Mahon L Maguire
- British Heart Foundation Experimental Magnetic Resonance Unit, Radcliffe Department of Medicine - Division of Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Sairam Geethanath
- Medical Imaging Research Centre, Dayananda Sagar College of Engineering, Bangalore, 560078, India
| | - Craig A Lygate
- British Heart Foundation Experimental Magnetic Resonance Unit, Radcliffe Department of Medicine - Division of Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Vikram D Kodibagkar
- School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, 85287-9709, USA
| | - Jürgen E Schneider
- British Heart Foundation Experimental Magnetic Resonance Unit, Radcliffe Department of Medicine - Division of Cardiovascular Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK.
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Ruparelia N, Godec J, Lee R, Chai JT, Dall'Armellina E, McAndrew D, Digby JE, Forfar JC, Prendergast BD, Kharbanda RK, Banning AP, Neubauer S, Lygate CA, Channon KM, Haining NW, Choudhury RP. Acute myocardial infarction activates distinct inflammation and proliferation pathways in circulating monocytes, prior to recruitment, and identified through conserved transcriptional responses in mice and humans. Eur Heart J 2015; 36:1923-34. [PMID: 25982896 PMCID: PMC4571177 DOI: 10.1093/eurheartj/ehv195] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 04/29/2015] [Indexed: 11/13/2022] Open
Abstract
AIMS Monocytes play critical roles in tissue injury and repair following acute myocardial infarction (AMI). Specifically targeting inflammatory monocytes in experimental models leads to reduced infarct size and improved healing. However, data from humans are sparse, and it remains unclear whether monocytes play an equally important role in humans. The aim of this study was to investigate whether the monocyte response following AMI is conserved between humans and mice and interrogate patterns of gene expression to identify regulated functions. METHODS AND RESULTS Thirty patients (AMI) and 24 control patients (stable coronary atherosclerosis) were enrolled. Female C57BL/6J mice (n = 6/group) underwent AMI by surgical coronary ligation. Myocardial injury was quantified by magnetic resonance imaging (human) and echocardiography (mice). Peripheral monocytes were isolated at presentation and at 48 h. RNA from separated monocytes was hybridized to Illumina beadchips. Acute myocardial infarction resulted in a significant peripheral monocytosis in both species that positively correlated with the extent of myocardial injury. Analysis of the monocyte transcriptome following AMI demonstrated significant conservation and identified inflammation and mitosis as central processes to this response. These findings were validated in both species. CONCLUSIONS Our findings show that the monocyte transcriptome is conserved between mice and humans following AMI. Patterns of gene expression associated with inflammation and proliferation appear to be switched on prior to their infiltration of injured myocardium suggesting that the specific targeting of inflammatory and proliferative processes in these immune cells in humans are possible therapeutic strategies. Importantly, they could be effective in the hours after AMI.
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Affiliation(s)
- Neil Ruparelia
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Jernej Godec
- Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Boston, MA 02115, USA
| | - Regent Lee
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - Joshua T Chai
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - Erica Dall'Armellina
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK Acute Vascular Imaging Centre, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - Debra McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - Janet E Digby
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - J Colin Forfar
- Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | | | - Rajesh K Kharbanda
- Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Adrian P Banning
- Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
| | - Keith M Channon
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK
| | - Nicholas W Haining
- Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Boston, MA 02115, USA
| | - Robin P Choudhury
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK Oxford Heart Centre, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK Acute Vascular Imaging Centre, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, Headley Way, Oxford OX3 9DU, UK
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Douglas G, Hale AB, Crabtree MJ, Ryan BJ, Hansler A, Watschinger K, Gross SS, Lygate CA, Alp NJ, Channon KM. A requirement for Gch1 and tetrahydrobiopterin in embryonic development. Dev Biol 2015; 399:129-138. [PMID: 25557619 PMCID: PMC4347993 DOI: 10.1016/j.ydbio.2014.12.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 12/19/2014] [Accepted: 12/20/2014] [Indexed: 10/28/2022]
Abstract
INTRODUCTION GTP cyclohydrolase I (GTPCH) catalyses the first and rate-limiting reaction in the synthesis of the enzymatic cofactor, tetrahydrobiopterin (BH4). Loss of function mutations in the GCH1 gene lead to congenital neurological diseases such as DOPA-responsive dystonia and hyperphenylalaninemia. However, little is known about how GTPCH and BH4 affects embryonic development in utero, and in particular whether metabolic replacement or supplementation in pregnancy is sufficient to rescue genetic GTPCH deficiency in the developing embryo. METHODS AND RESULTS Gch1 deficient mice were generated by the insertion of loxP sites flanking exons 2-3 of the Gch1 gene. Gch1(fl/fl) mice were bred with Sox2cre mice to generate mice with global Gch1 deficiency. Genetic ablation of Gch1 caused embryonic lethality by E13.5. Despite loss of Gch1 mRNA and GTPCH enzymatic activity, whole embryo BH4 levels were maintained until E11.5, indicating sufficient maternal transfer of BH4 to reach this stage of development. After E11.5, Gch1(-/-) embryos were deficient in BH4, but an unbiased metabolomic screen indicated that the lethality was not due to a gross disturbance in metabolic profile. Embryonic lethality in Gch1(-/-) embryos was not caused by structural abnormalities, but was associated with significant bradycardia at E11.5. Embryonic lethality was not rescued by maternal supplementation of BH4, but was partially rescued, up to E15.5, by maternal supplementation of BH4 and l-DOPA. CONCLUSION These findings demonstrate a requirement for Gch1 in embryonic development and have important implications for the understanding of pathogenesis and treatment of genetic BH4 deficiencies, as well as the identification of new potential roles for BH4.
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Affiliation(s)
- Gillian Douglas
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Ashley B Hale
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - Mark J Crabtree
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - Brent J Ryan
- Oxford Parkinson׳s Disease Centre, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Alex Hansler
- Department of Pharmacology, Weill Cornell Medical College, NY, USA
| | - Katrin Watschinger
- Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Steven S Gross
- Department of Pharmacology, Weill Cornell Medical College, NY, USA
| | - Craig A Lygate
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - Nicholas J Alp
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
| | - Keith M Channon
- BHF Centre of Research Excellence, Division of Cardiovascular Medicine, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK
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Faller KME, McAndrew DJ, Schneider JE, Lygate CA. Refinement of analgesia following thoracotomy and experimental myocardial infarction using the Mouse Grimace Scale. Exp Physiol 2015; 100:164-72. [PMID: 25480160 PMCID: PMC4340041 DOI: 10.1113/expphysiol.2014.083139] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [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: 09/23/2014] [Accepted: 11/24/2014] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? There is an ethical imperative to optimize analgesia protocols for laboratory animals, but this is impeded by our inability to recognize pain reliably. We examined whether the Mouse Grimace Scale (MGS) provides benefits over a standard welfare scoring system for identifying a low level of pain in the frequently used murine surgical model of myocardial infarction. What is the main finding and its importance? Low-level pain, responsive to analgesia, was detected by MGS but not standard methods. In this model, most of the pain is attributable to the thoracotomy, excepted in mice with very large infarcts. This approach represents a model for assessing postsurgical analgesia in rodents. The Mouse Grimace Scale (MGS) was developed for assessing pain severity, but the general applicability to complex postsurgical pain has not been established. We sought to determine whether the MGS provides benefits over and above a standard welfare scoring system for identifying pain in mice following experimental myocardial infarction. Female C57BL/6J mice (n = 60), anaesthetized with isoflurane, were subjected to thoracotomy with ligation of a coronary artery or sham procedure. A single s.c. dose of buprenorphine (1.1 mg kg(-1) ) was given at the time of surgery and pain assessed at 24 h by MGS and a procedure-specific welfare scoring system. In some animals, a second dose of 0.6 mg kg(-1) buprenorphine was given and pain assessment repeated after 30 min. The MGS was scored from multiple photographs by two independent blinded observers with good correlation (r = 0.98). Using the average MGS score of both observers, we identified a subset of mice with low scores that were not considered to be in pain by the welfare scoring system or by single observer MGS. These mice showed a significant improvement with additional analgesia, suggesting that this low-level pain is real. Pain attributable to the myocardial injury, as opposed to thoracotomy, persisted at 24 h only in mice with large infarcts >40%. In conclusion, the use of a multi-observer, post hoc version of the MGS is a sensitive tool to assess the efficacy of postsurgical analgesic protocols. Following surgical induction of myocardial infarction, we identified a significant proportion of mice that were in low-level pain at 24 h that were not identified by other assessment methods.
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Affiliation(s)
- Kiterie M E Faller
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation Centre of Research Excellence and Wellcome Trust Centre for Human Genetics, University of Oxford, UK; School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
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Whittington HJ, Atzler D, Zervou S, Faller KME, McAndrew DJ, Choe C, Isbrandt D, Schneider JE, Neubauer S, Lygate CA. LOSS OF HOMOARGININE IS RESPONSIBLE FOR CARDIAC DYSFUNCTION IN CREATINE-DEFICIENT ARGININE:GLYCINE AMIDINOTRANSFERASE (AGAT) KNOCKOUT MICE. Heart 2014. [DOI: 10.1136/heartjnl-2014-306916.33] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Aksentijević D, Zervou S, Faller KME, McAndrew DJ, Schneider JE, Neubauer S, Lygate CA. Myocardial creatine levels do not influence response to acute oxidative stress in isolated perfused heart. PLoS One 2014; 9:e109021. [PMID: 25272153 PMCID: PMC4182806 DOI: 10.1371/journal.pone.0109021] [Citation(s) in RCA: 13] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 09/01/2014] [Indexed: 01/01/2023] Open
Abstract
Background Multiple studies suggest creatine mediates anti-oxidant activity in addition to its established role in cellular energy metabolism. The functional significance for the heart has yet to be established, but antioxidant activity could contribute to the cardioprotective effect of creatine in ischaemia/reperfusion injury. Objectives To determine whether intracellular creatine levels influence responses to acute reactive oxygen species (ROS) exposure in the intact beating heart. We hypothesised that mice with elevated creatine due to over-expression of the creatine transporter (CrT-OE) would be relatively protected, while mice with creatine-deficiency (GAMT KO) would fare worse. Methods and Results CrT-OE mice were pre-selected for creatine levels 20–100% above wild-type using invivo1H–MRS. Hearts were perfused in isovolumic Langendorff mode and cardiac function monitored throughout. After 20 min equilibration, hearts were perfused with either H2O2 0.5 µM (30 min), or the anti-neoplastic drug doxorubicin 15 µM (100 min). Protein carbonylation, creatine kinase isoenzyme activities and phospho-PKCδ expression were quantified in perfused hearts as markers of oxidative damage and apoptotic signalling. Wild-type hearts responded to ROS challenge with a profound decline in contractile function that was ameliorated by co-administration of catalase or dexrazoxane as positive controls. In contrast, the functional deterioration in CrT-OE and GAMT KO hearts was indistinguishable from wild-type controls, as was the extent of oxidative damage and apoptosis. Exogenous creatine supplementation also failed to protect hearts from doxorubicin-induced dysfunction. Conclusions Intracellular creatine levels do not influence the response to acute ROS challenge in the intact beating heart, arguing against creatine exerting (patho-)physiologically relevant anti-oxidant activity.
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Affiliation(s)
- Dunja Aksentijević
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Kiterie M. E. Faller
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Debra J. McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Jurgen E. Schneider
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
| | - Craig A. Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine and British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Abstract
The creatine kinase (CK) system is thought to play an integral role in maintaining levels of chemical energy in the form of ATP, which is essential for normal cardiac function. In the failing heart, it has long been established that multiple components of CK energy metabolism are commonly impaired and that these correlate with disease severity. A recent study published in Science Translational Medicine adds significantly to this body of evidence by demonstrating that the rate of ATP transfer via CK, measured noninvasively by magnetic resonance spectroscopy, is an independent predictor of adverse clinical outcome in patients with nonischemic cardiomyopathy. This finding invites speculation on the future role of metabolic imaging for risk stratification in patients with heart failure. The authors further assert an implied causal role for energetics in disease progression. Although this is not supported by recent findings in loss-of-function mouse models, there is, nonetheless, a strong argument for the development of novel metabolic therapies for the failing heart.
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Affiliation(s)
- Craig A Lygate
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, British Heart Foundation Centre of Research Excellence, University of Oxford, Oxford, United Kingdom
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Aksentijević D, McAndrew DJ, Karlstädt A, Zervou S, Sebag-Montefiore L, Cross R, Douglas G, Regitz-Zagrosek V, Lopaschuk GD, Neubauer S, Lygate CA. Cardiac dysfunction and peri-weaning mortality in malonyl-coenzyme A decarboxylase (MCD) knockout mice as a consequence of restricting substrate plasticity. J Mol Cell Cardiol 2014; 75:76-87. [PMID: 25066696 PMCID: PMC4169183 DOI: 10.1016/j.yjmcc.2014.07.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 07/15/2014] [Accepted: 07/16/2014] [Indexed: 01/21/2023]
Abstract
UNLABELLED Inhibition of malonyl-coenzyme A decarboxylase (MCD) shifts metabolism from fatty acid towards glucose oxidation, which has therapeutic potential for obesity and myocardial ischemic injury. However, ~40% of patients with MCD deficiency are diagnosed with cardiomyopathy during infancy. AIM To clarify the link between MCD deficiency and cardiac dysfunction in early life and to determine the contributing systemic and cardiac metabolic perturbations. METHODS AND RESULTS MCD knockout mice ((-/-)) exhibited non-Mendelian genotype ratios (31% fewer MCD(-/-)) with deaths clustered around weaning. Immediately prior to weaning (18days) MCD(-/-) mice had lower body weights, elevated body fat, hepatic steatosis and glycogen depletion compared to wild-type littermates. MCD(-/-) plasma was hyperketonemic, hyperlipidemic, had 60% lower lactate levels and markers of cellular damage were elevated. MCD(-/-) hearts exhibited hypertrophy, impaired ejection fraction and were energetically compromised (32% lower total adenine nucleotide pool). However differences between WT and MCD(-/-) converged with age, suggesting that, in surviving MCD(-/-) mice, early cardiac dysfunction resolves over time. These observations were corroborated by in silico modelling of cardiomyocyte metabolism, which indicated improvement of the MCD(-/-) metabolic phenotype and improved cardiac efficiency when switched from a high-fat diet (representative of suckling) to a standard post-weaning diet, independent of any developmental changes. CONCLUSIONS MCD(-/-) mice consistently exhibited cardiac dysfunction and severe metabolic perturbations while on a high-fat, low carbohydrate diet of maternal milk and these gradually resolved post-weaning. This suggests that dysfunction is a common feature of MCD deficiency during early development, but that severity is dependent on composition of dietary substrates.
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Affiliation(s)
- Dunja Aksentijević
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Debra J McAndrew
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Anja Karlstädt
- Institute of Gender in Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany; Center for Cardiovascular Research, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Sevasti Zervou
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Liam Sebag-Montefiore
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Rebecca Cross
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Gillian Douglas
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Vera Regitz-Zagrosek
- Institute of Gender in Medicine, Charité-Universitätsmedizin Berlin, Berlin, Germany; Center for Cardiovascular Research, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Gary D Lopaschuk
- Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK
| | - Craig A Lygate
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, UK; British Heart Foundation Centre for Research Excellence, University of Oxford, UK.
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