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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] [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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2
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Lopez-Schenk R, Collins NL, Schenk NA, Beard DA. Integrated Functions of Cardiac Energetics, Mechanics, and Purine Nucleotide Metabolism. Compr Physiol 2023; 14:5345-5369. [PMID: 38158366 PMCID: PMC10956446 DOI: 10.1002/cphy.c230011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Purine nucleotides play central roles in energy metabolism in the heart. Most fundamentally, the free energy of hydrolysis of the adenine nucleotide adenosine triphosphate (ATP) provides the thermodynamic driving force for numerous cellular processes including the actin-myosin crossbridge cycle. Perturbations to ATP supply and/or demand in the myocardium lead to changes in the homeostatic balance between purine nucleotide synthesis, degradation, and salvage, potentially affecting myocardial energetics and, consequently, myocardial mechanics. Indeed, both acute myocardial ischemia and decompensatory remodeling of the myocardium in heart failure are associated with depletion of myocardial adenine nucleotides and with impaired myocardial mechanical function. Yet there remain gaps in the understanding of mechanistic links between adenine nucleotide degradation and contractile dysfunction in heart disease. The scope of this article is to: (i) review current knowledge of the pathways of purine nucleotide depletion and salvage in acute ischemia and in chronic heart disease; (ii) review hypothesized mechanisms linking myocardial mechanics and energetics with myocardial adenine nucleotide regulation; and (iii) highlight potential targets for treating myocardial metabolic and mechanical dysfunction associated with these pathways. It is hypothesized that an imbalance in the degradation, salvage, and synthesis of adenine nucleotides leads to a net loss of adenine nucleotides in both acute ischemia and under chronic high-demand conditions associated with the development of heart failure. This reduction in adenine nucleotide levels results in reduced myocardial ATP and increased myocardial inorganic phosphate. Both of these changes have the potential to directly impact tension development and mechanical work at the cellular level. © 2024 American Physiological Society. Compr Physiol 14:5345-5369, 2024.
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Affiliation(s)
- Rachel Lopez-Schenk
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Nicole L Collins
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Noah A Schenk
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
| | - Daniel A Beard
- Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, USA
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Fujimoto W, Nagao M, Nishimori M, Shinohara M, Takemoto M, Kuroda K, Yamashita S, Imanishi J, Iwasaki M, Todoroki T, Okuda M, Tanaka H, Ishida T, Toh R, Hirata KI. Association Between Serum 3-Hydroxyisobutyric Acid and Prognosis in Patients With Chronic Heart Failure - An Analysis of the KUNIUMI Registry Chronic Cohort. Circ J 2023; 88:110-116. [PMID: 37967948 DOI: 10.1253/circj.cj-23-0577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
BACKGROUND Diabetes increases the risk of heart failure (HF). 3-Hydroxyisobutyric acid (3-HIB) is a muscle-derived metabolite reflecting systemic insulin resistance. In this study, we investigated the prognostic impact of 3-HIB in patients with chronic HF.Methods and Results: The KUNIUMI Registry chronic cohort is a community-based cohort study of chronic HF in Awaji Island, Japan. We analyzed the association between serum 3-HIB concentrations and adverse cardiovascular (CV) events in 784 patients from this cohort. Serum 3-HIB concentrations were significantly higher in patients with than without diabetes (P=0.0229) and were positively correlated with several metabolic parameters. According to Kaplan-Meier analysis, rates of CV death and HF hospitalization at 2 years were significantly higher among HF patients without diabetes in the high 3-HIB group (3-HIB concentrations above the median; i.e., >11.30 μmol/L) than in the low 3-HIB group (log-rank P=0.0151 and P=0.0344, respectively). Multivariable Cox proportional hazard models adjusted for established risk factors for HF revealed high 3-HIB as an independent predictor of CV death (hazard ratio [HR] 1.82; 95% confidence interval [CI] 1.16-2.85; P=0.009) and HF hospitalization (HR 1.72; 95% CI 1.17-2.53, P=0.006) in HF patients without diabetes, whereas no such trend was seen in subjects with diabetes. CONCLUSIONS In a community cohort, circulating 3-HIB concentrations were associated with prognosis in chronic HF patients without diabetes.
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Affiliation(s)
- Wataru Fujimoto
- Department of Cardiology, Hyogo Prefectural Awaji Medical Center
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine
| | - Manabu Nagao
- Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine
| | - Makoto Nishimori
- Division of Molecular Epidemiology, Kobe University Graduate School of Medicine
| | - Masakazu Shinohara
- Division of Molecular Epidemiology, Kobe University Graduate School of Medicine
- The Integrated Center for Mass Spectrometry, Kobe University Graduate School of Medicine
| | - Makoto Takemoto
- Department of Cardiology, Hyogo Prefectural Awaji Medical Center
| | - Koji Kuroda
- Department of Cardiology, Hyogo Prefectural Awaji Medical Center
| | | | - Junichi Imanishi
- Department of Cardiology, Hyogo Prefectural Awaji Medical Center
| | | | | | - Masanori Okuda
- Department of Cardiology, Hyogo Prefectural Awaji Medical Center
| | - Hidekazu Tanaka
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine
| | - Tatsuro Ishida
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine
| | - Ryuji Toh
- Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine
| | - Ken-Ichi Hirata
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine
- Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine
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Kloock S, Ziegler CG, Dischinger U. Obesity and its comorbidities, current treatment options and future perspectives: Challenging bariatric surgery? Pharmacol Ther 2023; 251:108549. [PMID: 37879540 DOI: 10.1016/j.pharmthera.2023.108549] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/08/2023] [Accepted: 10/19/2023] [Indexed: 10/27/2023]
Abstract
Obesity and its comorbidities, including type 2 diabetes mellitus, cardiovascular disease, heart failure and non-alcoholic liver disease are a major health and economic burden with steadily increasing numbers worldwide. The need for effective pharmacological treatment options is strong, but, until recently, only few drugs have proven sufficient efficacy and safety. This article provides a comprehensive overview of obesity and its comorbidities, with a special focus on organ-specific pathomechanisms. Bariatric surgery as the so far most-effective therapeutic strategy, current pharmacological treatment options and future treatment strategies will be discussed. An increasing knowledge about the gut-brain axis and especially the identification and physiology of incretins unfolds a high number of potential drug candidates with impressive weight-reducing potential. Future multi-modal therapeutic concepts in obesity treatment may surpass the effectivity of bariatric surgery not only with regard to weight loss, but also to associated comorbidities.
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Affiliation(s)
- Simon Kloock
- Department of Internal Medicine, Division of Endocrinology and Diabetes, University Hospital, University of Würzburg, Würzburg, Germany
| | - Christian G Ziegler
- Department of Internal Medicine, Division of Endocrinology and Diabetes, University Hospital, University of Würzburg, Würzburg, Germany; Department of Internal Medicine III, University Hospital Carl Gustav Carus Dresden, Dresden, Germany
| | - Ulrich Dischinger
- Department of Internal Medicine, Division of Endocrinology and Diabetes, University Hospital, University of Würzburg, Würzburg, Germany; Comprehensive Heart Failure Center, Würzburg, Germany.
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Kasa G, Bayes-Genis A, Delgado V. Latest Updates in Heart Failure Imaging. Heart Fail Clin 2023; 19:407-418. [PMID: 37714583 DOI: 10.1016/j.hfc.2023.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 09/17/2023]
Abstract
Heart failure (HF), a challenging and heterogeneous syndrome, still remains a major health problem worldwide, despite all the advances in prevention, diagnosis, and treatment of cardiovascular disease. Cardiac imaging plays a pivotal role in the classification of HF, accurate diagnosis of underlying etiology and decision-making. Integration of other imaging techniques such as cardiac magnetic resonance, nuclear imaging, and exercise imaging testing is important to characterize HF accurately. This article reviews the role of multimodality imaging to diagnose patients with HF.
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Affiliation(s)
- Gizem Kasa
- Cardiovascular Imaging Section, Department of Cardiology, Heart Institute, University Hospital Germans Trias i Pujol, Badalona, Spain
| | - Antoni Bayes-Genis
- Cardiovascular Imaging Section, Department of Cardiology, Heart Institute, University Hospital Germans Trias i Pujol, Badalona, Spain
| | - Victoria Delgado
- Cardiovascular Imaging Section, Department of Cardiology, Heart Institute, University Hospital Germans Trias i Pujol, Badalona, Spain.
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Hundertmark MJ, Adler A, Antoniades C, Coleman R, Griffin JL, Holman RR, Lamlum H, Lee J, Massey D, Miller JJ, Milton JE, Monga S, Mózes FE, Nazeer A, Raman B, Rider O, Rodgers CT, Valkovič L, Wicks E, Mahmod M, Neubauer S. Assessment of Cardiac Energy Metabolism, Function, and Physiology in Patients With Heart Failure Taking Empagliflozin: The Randomized, Controlled EMPA-VISION Trial. Circulation 2023; 147:1654-1669. [PMID: 37070436 PMCID: PMC10212585 DOI: 10.1161/circulationaha.122.062021] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 03/16/2023] [Indexed: 04/19/2023]
Abstract
BACKGROUND Sodium-glucose co-transporter 2 inhibitors (SGLT2i) have emerged as a paramount treatment for patients with heart failure (HF), irrespective of underlying reduced or preserved ejection fraction. However, a definite cardiac mechanism of action remains elusive. Derangements in myocardial energy metabolism are detectable in all HF phenotypes, and it was proposed that SGLT2i may improve energy production. The authors aimed to investigate whether treatment with empagliflozin leads to changes in myocardial energetics, serum metabolomics, and cardiorespiratory fitness. METHODS EMPA-VISION (Assessment of Cardiac Energy Metabolism, Function and Physiology in Patients With Heart Failure Taking Empagliflozin) is a prospective, randomized, double-blind, placebo-controlled, mechanistic trial that enrolled 72 symptomatic patients with chronic HF with reduced ejection fraction (HFrEF; n=36; left ventricular ejection fraction ≤40%; New York Heart Association class ≥II; NT-proBNP [N-terminal pro-B-type natriuretic peptide] ≥125 pg/mL) and HF with preserved ejection fraction (HFpEF; n=36; left ventricular ejection fraction ≥50%; New York Heart Association class ≥II; NT-proBNP ≥125 pg/mL). Patients were stratified into respective cohorts (HFrEF versus HFpEF) and randomly assigned to empagliflozin (10 mg; n=35: 17 HFrEF and 18 HFpEF) or placebo (n=37: 19 HFrEF and 18 HFpEF) once daily for 12 weeks. The primary end point was a change in the cardiac phosphocreatine:ATP ratio (PCr/ATP) from baseline to week 12, determined by phosphorus magnetic resonance spectroscopy at rest and during peak dobutamine stress (65% of age-maximum heart rate). Mass spectrometry on a targeted set of 19 metabolites was performed at baseline and after treatment. Other exploratory end points were investigated. RESULTS Empagliflozin treatment did not change cardiac energetics (ie, PCr/ATP) at rest in HFrEF (adjusted mean treatment difference [empagliflozin - placebo], -0.25 [95% CI, -0.58 to 0.09]; P=0.14) or HFpEF (adjusted mean treatment difference, -0.16 [95% CI, -0.60 to 0.29]; P=0.47]. Likewise, there were no changes in PCr/ATP during dobutamine stress in HFrEF (adjusted mean treatment difference, -0.13 [95% CI, -0.35 to 0.09]; P=0.23) or HFpEF (adjusted mean treatment difference, -0.22 [95% CI, -0.66 to 0.23]; P=0.32). No changes in serum metabolomics or levels of circulating ketone bodies were observed. CONCLUSIONS In patients with either HFrEF or HFpEF, treatment with 10 mg of empagliflozin once daily for 12 weeks did not improve cardiac energetics or change circulating serum metabolites associated with energy metabolism when compared with placebo. Based on our results, it is unlikely that enhancing cardiac energy metabolism mediates the beneficial effects of SGLT2i in HF. REGISTRATION URL: https://www. CLINICALTRIALS gov; Unique identifier: NCT03332212.
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Affiliation(s)
- Moritz J. Hundertmark
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
- Department of Internal Medicine I, University Hospital Wuerzburg, Germany (M.J.H.)
| | - Amanda Adler
- Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine (A.A., R.C., R.R.H., J.E.M.), University of Oxford, UK
| | - Charalambos Antoniades
- Acute Multidisciplinary Imaging and Interventional Centre (C.A., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Ruth Coleman
- Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine (A.A., R.C., R.R.H., J.E.M.), University of Oxford, UK
| | | | - Rury R. Holman
- Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine (A.A., R.C., R.R.H., J.E.M.), University of Oxford, UK
| | - Hanan Lamlum
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Jisoo Lee
- John Radcliffe Hospital, Oxford University Hospitals National Health Service Foundation Trust, UK (J.L., E.W.)
| | - Daniel Massey
- Elderbrook Solutions GmbH on behalf of Boehringer Ingelheim Pharma GmbH and Co. KG, Biberach, Germany (D.M.)
| | - Jack J.J.J. Miller
- Department of Physics (J.M.), University of Oxford, UK
- Department of Clinical Medicine, Aarhus University, Denmark (J.J.M.)
| | - Joanne E. Milton
- Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, Radcliffe Department of Medicine (A.A., R.C., R.R.H., J.E.M.), University of Oxford, UK
| | - Shveta Monga
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Ferenc E. Mózes
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Areesha Nazeer
- Oxford National Institutes of Health and Care Research Biomedical Research Centre, Oxford University Hospitals, Oxford, UK (R.R.H.)
| | - Betty Raman
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Oliver Rider
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Christopher T. Rodgers
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
- Wolfson Brain Imaging Centre, Department of Clinical Neurosciences, Cambridge Biomedical Campus, UK (C.T.R.)
| | - Ladislav Valkovič
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
- Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava (L.V.)
| | - Eleanor Wicks
- John Radcliffe Hospital, Oxford University Hospitals National Health Service Foundation Trust, UK (J.L., E.W.)
| | - Masliza Mahmod
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research (M.J.H., H.L., S.M., F.E.M., B.R., O.R., C.T.R., L.V., M.M., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
- Acute Multidisciplinary Imaging and Interventional Centre (C.A., S.N.), Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, UK
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Burrage MK, Lewis AJ, Miller JJJ. Functional and Metabolic Imaging in Heart Failure with Preserved Ejection Fraction: Promises, Challenges, and Clinical Utility. Cardiovasc Drugs Ther 2023; 37:379-399. [PMID: 35881280 PMCID: PMC10014679 DOI: 10.1007/s10557-022-07355-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/08/2022] [Indexed: 11/29/2022]
Abstract
Heart failure with preserved ejection fraction (HFpEF) is recognised as an increasingly prevalent, morbid and burdensome condition with a poor outlook. Recent advances in both the understanding of HFpEF and the technological ability to image cardiac function and metabolism in humans have simultaneously shone a light on the molecular basis of this complex condition of diastolic dysfunction, and the inflammatory and metabolic changes that are associated with it, typically in the context of a complex patient. This review both makes the case for an integrated assessment of the condition, and highlights that metabolic alteration may be a measurable outcome for novel targeted forms of medical therapy. It furthermore highlights how recent technological advancements and advanced medical imaging techniques have enabled the characterisation of the metabolism and function of HFpEF within patients, at rest and during exercise.
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Affiliation(s)
- Matthew K Burrage
- Oxford Centre for Clinical Cardiovascular Magnetic Resonance Research (OCMR); Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Andrew J Lewis
- Oxford Centre for Clinical Cardiovascular Magnetic Resonance Research (OCMR); Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, UK
| | - Jack J J. Miller
- Oxford Centre for Clinical Cardiovascular Magnetic Resonance Research (OCMR); Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, UK
- Department of Physiology, Anatomy and Genetics, University of Oxford, Parks Road, Oxford, UK
- The PET Research Centre and The MR Research Centre, Aarhus University, Aarhus, Denmark
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, UK
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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] [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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9
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Tsampasian V, Cameron D, Sobhan R, Bazoukis G, Vassiliou VS. Phosphorus Magnetic Resonance Spectroscopy ( 31P MRS) and Cardiovascular Disease: The Importance of Energy. Medicina (B Aires) 2023; 59:medicina59010174. [PMID: 36676798 PMCID: PMC9866867 DOI: 10.3390/medicina59010174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/10/2023] [Accepted: 01/13/2023] [Indexed: 01/17/2023] Open
Abstract
Background and Objectives: The heart is the organ with the highest metabolic demand in the body, and it relies on high ATP turnover and efficient energy substrate utilisation in order to function normally. The derangement of myocardial energetics may lead to abnormalities in cardiac metabolism, which herald the symptoms of heart failure (HF). In addition, phosphorus magnetic resonance spectroscopy (31P MRS) is the only available non-invasive method that allows clinicians and researchers to evaluate the myocardial metabolic state in vivo. This review summarises the importance of myocardial energetics and provides a systematic review of all the available research studies utilising 31P MRS to evaluate patients with a range of cardiac pathologies. Materials and Methods: We have performed a systematic review of all available studies that used 31P MRS for the investigation of myocardial energetics in cardiovascular disease. Results: A systematic search of the Medline database, the Cochrane library, and Web of Science yielded 1092 results, out of which 62 studies were included in the systematic review. The 31P MRS has been used in numerous studies and has demonstrated that impaired myocardial energetics is often the beginning of pathological processes in several cardiac pathologies. Conclusions: The 31P MRS has become a valuable tool in the understanding of myocardial metabolic changes and their impact on the diagnosis, risk stratification, and prognosis of patients with cardiovascular diseases.
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Affiliation(s)
- Vasiliki Tsampasian
- Norwich Medical School, University of East Anglia, Bob Champion Research & Education Building, Research Park, Rosalind Franklin Rd, Norwich NR4 7UQ, UK
- Correspondence: (V.T.); (V.S.V.)
| | - Donnie Cameron
- C.J. Gorter MRI Center, Department of Radiology, Leiden University Medical Centre, 2333 ZA Leiden, The Netherlands
| | - Rashed Sobhan
- Norwich Medical School, University of East Anglia, Bob Champion Research & Education Building, Research Park, Rosalind Franklin Rd, Norwich NR4 7UQ, UK
| | - George Bazoukis
- Department of Cardiology, Larnaca General Hospital, Larnaca 6301, Cyprus
- Department of Basic and Clinical Sciences, University of Nicosia Medical School, Nicosia 2417, Cyprus
| | - Vassilios S. Vassiliou
- Norwich Medical School, University of East Anglia, Bob Champion Research & Education Building, Research Park, Rosalind Franklin Rd, Norwich NR4 7UQ, UK
- Correspondence: (V.T.); (V.S.V.)
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10
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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] [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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11
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Kumar RA, Thome T, Sharaf OM, Ryan TE, Arnaoutakis GJ, Jeng EI, Ferreira LF. Reversible Thiol Oxidation Increases Mitochondrial Electron Transport Complex Enzyme Activity but Not Respiration in Cardiomyocytes from Patients with End-Stage Heart Failure. Cells 2022; 11:cells11152292. [PMID: 35892589 PMCID: PMC9330889 DOI: 10.3390/cells11152292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 12/10/2022] Open
Abstract
Cardiomyocyte dysfunction in patients with end-stage heart failure with reduced ejection fraction (HFrEF) stems from mitochondrial dysfunction, which contributes to an energetic crisis. Mitochondrial dysfunction reportedly relates to increased markers of oxidative stress, but the impact of reversible thiol oxidation on myocardial mitochondrial function in patients with HFrEF has not been investigated. In the present study, we assessed mitochondrial function in ventricular biopsies from patients with end-stage HFrEF in the presence and absence of the thiol-reducing agent dithiothreitol (DTT). Isolated mitochondria exposed to DTT had increased enzyme activity of complexes I (p = 0.009) and III (p = 0.018) of the electron transport system, while complexes II (p = 0.630) and IV (p = 0.926) showed no changes. However, increased enzyme activity did not carry over to measurements of mitochondrial respiration in permeabilized bundles. Oxidative phosphorylation conductance (p = 0.439), maximal respiration (p = 0.312), and ADP sensitivity (p = 0.514) were unchanged by 5 mM DTT treatment. These results indicate that mitochondrial function can be modulated through reversible thiol oxidation, but other components of mitochondrial energy transfer are rate limiting in end-stage HFrEF. Optimal therapies to normalize cardiac mitochondrial respiration in patients with end-stage HFrEF may benefit from interventions to reverse thiol oxidation, which limits complex I and III activities.
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Affiliation(s)
- Ravi A. Kumar
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (R.A.K.); (T.T.); (T.E.R.)
| | - Trace Thome
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (R.A.K.); (T.T.); (T.E.R.)
| | - Omar M. Sharaf
- College of Medicine, University of Florida, Gainesville, FL 32611, USA;
| | - Terence E. Ryan
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (R.A.K.); (T.T.); (T.E.R.)
| | - George J. Arnaoutakis
- Department of Surgery, Division of Thoracic and Cardiovascular Surgery, University of Florida, Gainesville, FL 32611, USA; (G.J.A.); (E.I.J.)
| | - Eric I. Jeng
- Department of Surgery, Division of Thoracic and Cardiovascular Surgery, University of Florida, Gainesville, FL 32611, USA; (G.J.A.); (E.I.J.)
| | - Leonardo F. Ferreira
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL 32611, USA; (R.A.K.); (T.T.); (T.E.R.)
- Department of Physiology, Amsterdam UMC, 1081 HZ Amsterdam, The Netherlands
- Correspondence: ; Tel.: +1-352-294-1724
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12
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Yoshikawa S, Nagao M, Toh R, Shinohara M, Iino T, Irino Y, Nishimori M, Tanaka H, Satomi-Kobayashi S, Ishida T, Hirata KI. Inhibition of glutaminase 1-mediated glutaminolysis improves pathological cardiac remodeling. Am J Physiol Heart Circ Physiol 2022; 322:H749-H761. [PMID: 35275762 DOI: 10.1152/ajpheart.00692.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Alterations in cardiac metabolism are strongly associated with the pathogenesis of heart failure (HF). We recently reported that glutamine-dependent anaplerosis, termed glutaminolysis, was activated by H2O2 stimulation in rat cardiomyocytes, which seemed to be an adaptive response by which cardiomyocytes survive acute stress. However, the molecular mechanisms and fundamental roles of glutaminolysis in the pathophysiology of the failing heart are still unknown. Here, we treated wild-type mice (C57BL/6J) and rat neonatal cardiomyocytes (RNCMs) and fibroblasts (RNCFs) with angiotensin II (Ang II) to induce pathological cardiac remodeling. Glutaminase 1 (GLS1), a rate-limiting glutaminolysis enzyme, was significantly increased in Ang II-induced mouse hearts, RNCMs and RNCFs. Unexpectedly, a GLS1 inhibitor attenuated Ang II-induced left ventricular hypertrophy and fibrosis in the mice, and gene knockdown and pharmacological perturbation of GLS1 suppressed hypertrophy and the proliferation of RNCMs and RNCFs, respectively. Using mass spectrometry (MS)-based stable isotope tracing with 13C-labeled glutamine, we observed glutamine metabolic flux in Ang II-treated RNCMs and RNCFs. The incorporation of 13C atoms into tricarboxylic acid (TCA) cycle intermediates and their derivatives was markedly enhanced in both cell types, indicating the activation of glutaminolysis in hypertrophied heart. Notably, GLS1 inhibition reduced the production of glutamine-derived aspartate and citrate, which are required for the biosynthesis of nucleic acids and lipids, possibly contributing to the suppression of cardiac hypertrophy and fibrosis. The findings of the present study reveal that GLS1-mediated upregulation of glutaminolysis leads to maladaptive cardiac remodeling. Inhibition of this anaplerotic pathway could be a novel therapeutic approach for HF.
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Affiliation(s)
- Sachiko Yoshikawa
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Kobe, Hyogo, Japan
| | - Manabu Nagao
- Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine, Kobe, Kobe, Hyogo, Japan
| | - Ryuji Toh
- Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine, Kobe, Kobe, Hyogo, Japan
| | - Masakazu Shinohara
- Division of Epidemiology, Kobe University Graduate School of Medicine, Kobe, Japan; The Integrated Center for Mass Spectrometry, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takuya Iino
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Kobe, Hyogo, Japan
| | - Yasuhiro Irino
- Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Makoto Nishimori
- Division of Epidemiology, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Hidekazu Tanaka
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Seimi Satomi-Kobayashi
- Division of Cardiovascular Medicine, Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Kobe, Hyogo, Japan
| | - Tatsuro Ishida
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Kobe, Hyogo, Japan
| | - Ken-Ichi Hirata
- Division of Cardiovascular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan; Division of Evidence-based Laboratory Medicine, Kobe University Graduate School of Medicine, Kobe, kobe, Japan
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13
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Role of Creatine Supplementation in Conditions Involving Mitochondrial Dysfunction: A Narrative Review. Nutrients 2022; 14:nu14030529. [PMID: 35276888 PMCID: PMC8838971 DOI: 10.3390/nu14030529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 01/24/2022] [Accepted: 01/24/2022] [Indexed: 12/14/2022] Open
Abstract
Creatine monohydrate (CrM) is one of the most widely used nutritional supplements among active individuals and athletes to improve high-intensity exercise performance and training adaptations. However, research suggests that CrM supplementation may also serve as a therapeutic tool in the management of some chronic and traumatic diseases. Creatine supplementation has been reported to improve high-energy phosphate availability as well as have antioxidative, neuroprotective, anti-lactatic, and calcium-homoeostatic effects. These characteristics may have a direct impact on mitochondrion's survival and health particularly during stressful conditions such as ischemia and injury. This narrative review discusses current scientific evidence for use or supplemental CrM as a therapeutic agent during conditions associated with mitochondrial dysfunction. Based on this analysis, it appears that CrM supplementation may have a role in improving cellular bioenergetics in several mitochondrial dysfunction-related diseases, ischemic conditions, and injury pathology and thereby could provide therapeutic benefit in the management of these conditions. However, larger clinical trials are needed to explore these potential therapeutic applications before definitive conclusions can be drawn.
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14
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Abstract
Impaired cardiac energy metabolism has been proposed as a mechanism common to different heart failure aetiologies. The energy-depletion hypothesis was pursued by several researchers, and is still a topic of considerable interest. Unlike most organs, in the heart, the creatine kinase system represents a major component of the metabolic machinery, as it functions as an energy shuttle between mitochondria and cytosol. In heart failure, the decrease in creatine level anticipates the reduction in adenosine triphosphate, and the degree of myocardial phosphocreatine/adenosine triphosphate ratio reduction correlates with disease severity, contractile dysfunction, and myocardial structural remodelling. However, it remains to be elucidated whether an impairment of phosphocreatine buffer activity contributes to the pathophysiology of heart failure and whether correcting this energy deficit might prove beneficial. The effects of creatine deficiency and the potential utility of creatine supplementation have been investigated in experimental and clinical models, showing controversial findings. The goal of this article is to provide a comprehensive overview on the role of creatine in cardiac energy metabolism, the assessment and clinical value of creatine deficiency in heart failure, and the possible options for the specific metabolic therapy.
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15
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Müller J, Bertsch T, Volke J, Schmid A, Klingbeil R, Metodiev Y, Karaca B, Kim SH, Lindner S, Schupp T, Kittel M, Poschet G, Akin I, Behnes M. Narrative review of metabolomics in cardiovascular disease. J Thorac Dis 2021; 13:2532-2550. [PMID: 34012599 PMCID: PMC8107570 DOI: 10.21037/jtd-21-22] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cardiovascular diseases are accompanied by disorders in the cardiac metabolism. Furthermore, comorbidities often associated with cardiovascular disease can alter systemic and myocardial metabolism contributing to worsening of cardiac performance and health status. Biomarkers such as natriuretic peptides or troponins already support diagnosis, prognosis and treatment of patients with cardiovascular diseases and are represented in international guidelines. However, as cardiovascular diseases affect various pathophysiological pathways, a single biomarker approach cannot be regarded as ideal to reveal optimal clinical application. Emerging metabolomics technology allows the measurement of hundreds of metabolites in biological fluids or biopsies and thus to characterize each patient by its own metabolic fingerprint, improving our understanding of complex diseases, significantly altering the management of cardiovascular diseases and possibly personalizing medicine. This review outlines current knowledge, perspectives as well as limitations of metabolomics for diagnosis, prognosis and treatment of cardiovascular diseases such as heart failure, atherosclerosis, ischemic and non-ischemic cardiomyopathy. Furthermore, an ongoing research project tackling current inconsistencies as well as clinical applications of metabolomics will be discussed. Taken together, the application of metabolomics will enable us to gain more insights into pathophysiological interactions of metabolites and disease states as well as improving therapies of patients with cardiovascular diseases in the future.
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Affiliation(s)
- Julian Müller
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Thomas Bertsch
- Institute of Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, Nuremburg General Hospital, Paracelsus Medical University, Nuremberg, Germany
| | - Justus Volke
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Alexander Schmid
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Rebecca Klingbeil
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Yulian Metodiev
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Bican Karaca
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Seung-Hyun Kim
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Simon Lindner
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Tobias Schupp
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Maximilian Kittel
- Institute for Clinical Chemistry, Faculty of Medicine Mannheim, Heidelberg University, Mannheim, Germany
| | - Gernot Poschet
- Centre for Organismal Studies (COS), University of Heidelberg, Heidelberg, Germany
| | - Ibrahim Akin
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
| | - Michael Behnes
- First Department of Medicine, Faculty of Medicine Mannheim, University of Heidelberg, Mannheim, Germany
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16
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O'Sullivan O, Barker-Davies R, Chamley R, Sellon E, Jenkins D, Burley R, Holden L, Nicol AM, Phillip R, Bennett AN, Nicol E, Holdsworth DA. Defence Medical Rehabilitation Centre (DMRC) COVID-19 Recovery Service. BMJ Mil Health 2021; 169:271-276. [PMID: 33547188 DOI: 10.1136/bmjmilitary-2020-001681] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 01/09/2021] [Accepted: 01/11/2021] [Indexed: 11/04/2022]
Abstract
Coronavirus disease 2019 (COVID-19) causes significant mortality and morbidity, with an unknown impact in the medium to long term. Evidence from previous coronavirus epidemics indicates that there is likely to be a substantial burden of disease, potentially even in those with a mild acute illness. The clinical and occupational effects of COVID-19 are likely to impact on the operational effectiveness of the Armed Forces. Collaboration between Defence Primary Healthcare, Defence Secondary Healthcare, Defence Rehabilitation and Defence Occupational Medicine resulted in the Defence Medical Rehabilitation Centre COVID-19 Recovery Service (DCRS). This integrated clinical and occupational pathway uses cardiopulmonary assessment as a cornerstone to identify, diagnose and manage post-COVID-19 pathology.
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Affiliation(s)
- Oliver O'Sullivan
- Academic Department of Military Rehabilitation, Defence Medical Rehabilitation Centre, Stanford Hall, Loughborough, Nottinghamshire, UK.,Headquarters Army Medical Services (HQ AMS), Camberley, Surrey, UK
| | - R Barker-Davies
- Academic Department of Military Rehabilitation, Defence Medical Rehabilitation Centre, Stanford Hall, Loughborough, Nottinghamshire, UK.,School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - R Chamley
- Academic Department of Military Medicine, Birmingham, UK.,Oxford University Hospitals NHS Foundation Trust, Oxford, Oxfordshire, UK
| | - E Sellon
- Oxford University Hospitals NHS Foundation Trust, Oxford, Oxfordshire, UK.,Royal Centre for Defence Medicine, Birmingham, UK
| | - D Jenkins
- Oxford University Hospitals NHS Foundation Trust, Oxford, Oxfordshire, UK.,Royal Centre for Defence Medicine, Birmingham, UK
| | - R Burley
- Headquarters Defence Primary Healthcare, Lichfield, Staffordshire, UK
| | - L Holden
- Royal Centre for Defence Medicine, Birmingham, UK
| | - A M Nicol
- Defence Medical Rehabilitation Centre, Stanford Hall, Loughborough, Nottinghamshire, UK
| | - R Phillip
- Defence Medical Rehabilitation Centre, Stanford Hall, Loughborough, Nottinghamshire, UK
| | - A N Bennett
- Academic Department of Military Rehabilitation, Defence Medical Rehabilitation Centre, Stanford Hall, Loughborough, Nottinghamshire, UK.,National Heart and Lung Institute, Faculty of Medicine, Imperial College London, London, UK
| | - E Nicol
- Royal Centre for Defence Medicine, Birmingham, UK.,Royal Brompton Hospital, London, UK
| | - D A Holdsworth
- Academic Department of Military Medicine, Birmingham, UK .,Oxford University Hospitals NHS Foundation Trust, Oxford, Oxfordshire, UK
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17
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Chazot G, Lemoine S, Kocevar G, Kalbacher E, Sappey-Marinier D, Rouvière O, Juillard L. Intracellular Phosphate and ATP Depletion Measured by Magnetic Resonance Spectroscopy in Patients Receiving Maintenance Hemodialysis. J Am Soc Nephrol 2021; 32:229-237. [PMID: 33093193 PMCID: PMC7894675 DOI: 10.1681/asn.2020050716] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 09/13/2020] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND The precise origin of phosphate that is removed during hemodialysis remains unclear; only a minority comes from the extracellular space. One possibility is that the remaining phosphate originates from the intracellular compartment, but there have been no available data from direct assessment of intracellular phosphate in patients undergoing hemodialysis. METHODS We used phosphorus magnetic resonance spectroscopy to quantify intracellular inorganic phosphate (Pi), phosphocreatine (PCr), and βATP. In our pilot, single-center, prospective study, 11 patients with ESKD underwent phosphorus (31P) magnetic resonance spectroscopy examination during a 4-hour hemodialysis treatment. Spectra were acquired every 152 seconds during the hemodialysis session. The primary outcome was a change in the PCr-Pi ratio during the session. RESULTS During the first hour of hemodialysis, mean phosphatemia decreased significantly (-41%; P<0.001); thereafter, it decreased more slowly until the end of the session. We found a significant increase in the PCr-Pi ratio (+23%; P=0.001) during dialysis, indicating a reduction in intracellular Pi concentration. The PCr-βATP ratio increased significantly (+31%; P=0.001) over a similar time period, indicating a reduction in βATP. The change of the PCr-βATP ratio was significantly correlated to the change of depurated Pi. CONCLUSIONS Phosphorus magnetic resonance spectroscopy examination of patients with ESKD during hemodialysis treatment confirmed that depurated Pi originates from the intracellular compartment. This finding raises the possibility that excessive dialytic depuration of phosphate might adversely affect the intracellular availability of high-energy phosphates and ultimately, cellular metabolism. Further studies are needed to investigate the relationship between objective and subjective effects of hemodialysis and decreases of intracellular Pi and βATP content. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER Intracellular Phosphate Concentration Evolution During Hemodialysis by MR Spectroscopy (CIPHEMO), NCT03119818.
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Affiliation(s)
- Guillaume Chazot
- Service de néphrologie et d’exploration fonctionnelle rénale, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France
| | - Sandrine Lemoine
- Service de néphrologie et d’exploration fonctionnelle rénale, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France,CARMEN U1060 Institut National de la Santé et de la Recherche Médicale (Cardiovascular Metabolisme Nutrition), Université de Lyon, Université Claude Bernard, INSA de Lyon, Bron, France
| | - Gabriel Kocevar
- CREATIS (Centre de Recherche et d'Applications en Traitement de l'Image et du Signal) Unité Mixte de Recherche 5220 Centre National de la Recherche Scientifique and U1206 Institut National de la Santé et de la Recherche Médicale, Université de Lyon, Université Claude Bernard, INSA (Institut National Des Sciences Appliquées) de Lyon, Villeurbanne, France
| | - Emilie Kalbacher
- Service de néphrologie et d’exploration fonctionnelle rénale, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France
| | - Dominique Sappey-Marinier
- CREATIS (Centre de Recherche et d'Applications en Traitement de l'Image et du Signal) Unité Mixte de Recherche 5220 Centre National de la Recherche Scientifique and U1206 Institut National de la Santé et de la Recherche Médicale, Université de Lyon, Université Claude Bernard, INSA (Institut National Des Sciences Appliquées) de Lyon, Villeurbanne, France,CERMEP-Imagerie du vivant (Centre d'Etude et de Recherche Médicale par Emission de Positons), Université de Lyon, Bron, France
| | - Olivier Rouvière
- Service de radiologie, Hôpital Édouard-Herriot, Hospices Civils de Lyon, Lyon, France,Labtau U1032 Institut National de la Santé et de la Recherche Médicale, Université de Lyon, Université Claude Bernard, Villeurbanne, France
| | - Laurent Juillard
- Service de néphrologie et d’exploration fonctionnelle rénale, Hôpital Edouard Herriot, Hospices Civils de Lyon, Lyon, France,CARMEN U1060 Institut National de la Santé et de la Recherche Médicale (Cardiovascular Metabolisme Nutrition), Université de Lyon, Université Claude Bernard, INSA de Lyon, Bron, France
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18
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Lopez R, Marzban B, Gao X, Lauinger E, Van den Bergh F, Whitesall SE, Converso-Baran K, Burant CF, Michele DE, Beard DA. Impaired Myocardial Energetics Causes Mechanical Dysfunction in Decompensated Failing Hearts. FUNCTION 2020; 1:zqaa018. [PMID: 33074265 PMCID: PMC7552914 DOI: 10.1093/function/zqaa018] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 09/11/2020] [Accepted: 09/21/2020] [Indexed: 01/06/2023] Open
Abstract
Cardiac mechanical function is supported by ATP hydrolysis, which provides the chemical-free energy to drive the molecular processes underlying cardiac pumping. Physiological rates of myocardial ATP consumption require the heart to resynthesize its entire ATP pool several times per minute. In the failing heart, cardiomyocyte metabolic dysfunction leads to a reduction in the capacity for ATP synthesis and associated free energy to drive cellular processes. Yet it remains unclear if and how metabolic/energetic dysfunction that occurs during heart failure affects mechanical function of the heart. We hypothesize that changes in phosphate metabolite concentrations (ATP, ADP, inorganic phosphate) that are associated with decompensation and failure have direct roles in impeding contractile function of the myocardium in heart failure, contributing to the whole-body phenotype. To test this hypothesis, a transverse aortic constriction (TAC) rat model of pressure overload, hypertrophy, and decompensation was used to assess relationships between metrics of whole-organ pump function and myocardial energetic state. A multiscale computational model of cardiac mechanoenergetic coupling was used to identify and quantify the contribution of metabolic dysfunction to observed mechanical dysfunction. Results show an overall reduction in capacity for oxidative ATP synthesis fueled by either fatty acid or carbohydrate substrates as well as a reduction in total levels of adenine nucleotides and creatine in myocardium from TAC animals compared to sham-operated controls. Changes in phosphate metabolite levels in the TAC rats are correlated with impaired mechanical function, consistent with the overall hypothesis. Furthermore, computational analysis of myocardial metabolism and contractile dynamics predicts that increased levels of inorganic phosphate in TAC compared to control animals kinetically impair the myosin ATPase crossbridge cycle in decompensated hypertrophy/heart failure.
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Affiliation(s)
- Rachel Lopez
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Bahador Marzban
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Xin Gao
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Ellen Lauinger
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Françoise Van den Bergh
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Steven E Whitesall
- Frankel Cardiovascular Center Physiology and Phenotyping Core, University of Michigan, Ann Arbor, MI, USA
| | - Kimber Converso-Baran
- Frankel Cardiovascular Center Physiology and Phenotyping Core, University of Michigan, Ann Arbor, MI, USA
| | - Charles F Burant
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA,Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Daniel E Michele
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA,Frankel Cardiovascular Center Physiology and Phenotyping Core, University of Michigan, Ann Arbor, MI, USA
| | - Daniel A Beard
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI, USA,Address correspondence to D.A.B. (e-mail: )
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19
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Watson WD, Miller JJJ, Lewis A, Neubauer S, Tyler D, Rider OJ, Valkovič L. Use of cardiac magnetic resonance to detect changes in metabolism in heart failure. Cardiovasc Diagn Ther 2020; 10:583-597. [PMID: 32695639 DOI: 10.21037/cdt.2019.12.13] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The heart has a massive adenosine triphosphate (ATP) requirement, produced from the oxidation of metabolic substrates such as fat and glucose. Magnetic resonance spectroscopy offers a unique opportunity to probe this biochemistry: 31Phosphorus spectroscopy can demonstrate the production of ATP and quantify levels of the transport molecule phosphocreatine while 13Carbon spectroscopy can demonstrate the metabolic fates of glucose in real time. These techniques allow the metabolic deficits in heart failure to be interrogated and can be a potential future clinical tool.
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Affiliation(s)
- William D Watson
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Jack J J Miller
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Andrew Lewis
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Damian Tyler
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Oliver J Rider
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK
| | - Ladislav Valkovič
- Oxford Centre for Clinical Magnetic Resonance Research, Clarendon Laboratory, University of Oxford, Oxford, UK.,Department of Imaging Methods, Institute of Measurement Science, Slovak Academy of Sciences, Bratislava, Slovakia
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20
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Peterzan MA, Lewis AJM, Neubauer S, Rider OJ. Non-invasive investigation of myocardial energetics in cardiac disease using 31P magnetic resonance spectroscopy. Cardiovasc Diagn Ther 2020; 10:625-635. [PMID: 32695642 DOI: 10.21037/cdt-20-275] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cardiac metabolism and function are intrinsically linked. High-energy phosphates occupy a central and obligate position in cardiac metabolism, coupling oxygen and substrate fuel delivery to the myocardium with external work. This insight underlies the widespread clinical use of ischaemia testing. However, other deficits in high-energy phosphate metabolism (not secondary to supply-demand mismatch of oxygen and substrate fuels) may also be documented, and are of particular interest when found in the context of structural heart disease. This review introduces the scope of deficits in high-energy phosphate metabolism that may be observed in the myocardium, how to assess for them, and how they might be interpreted.
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Affiliation(s)
- Mark A Peterzan
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Andrew J M Lewis
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Oliver J Rider
- University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Radcliffe Department of Medicine, University of Oxford, Oxford, UK
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21
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Abstract
Inflammation has long been known to play a role in heart failure (HF). Earlier studies demonstrated that inflammation contributes to the pathogenesis of HF with reduced ejection fraction (HFrEF), and the knowledge about molecules and cell types specifically involved in inflammatory events has been constantly increased ever since. However, conflicting results of several trials with anti-inflammatory treatments led to the conclusions that inflammation does participate in the progression of HFrEF, but more likely it is not the primary event. Conversely, it has been suggested that inflammation drives the development of HF with preserved ejection fraction (HFpEF). Recently the pharmacological blockade of interleukin-1 has been shown to prevent HF hospitalization and mortality in patients with prior myocardial infarction, lending renewed support to the hypothesis that inflammation is a promising therapeutic target in HF. Inflammation has also been proposed to underlie both HF and commonly associated conditions, such as chronic kidney disease or cancer. Within this last paradigm, an emergent role has been ascribed to clonal hematopoiesis of indeterminate potential. Here, we summarize the recent evidence about the role of inflammation in HF, highlighting the similarities and differences in HFrEF vs. HFpEF, and discuss the diagnostic and therapeutic opportunities raised by antinflammatory-based approaches.
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Affiliation(s)
- Gabriele G Schiattarella
- Department of Internal Medicine (Cardiology), University of Texas Southwestern Medical Center, 6000 Harry Hines Blvd, NB11.208, Dallas, TX, 75390-8573, USA.
- Department of Advanced Biomedical Sciences, University of Naples Federico II, Naples, Italy.
| | - Vasco Sequeira
- Comprehensive Heart Failure Center (CHFC), University Clinic Würzburg, Würzburg, Germany
| | - Pietro Ameri
- Department of Internal Medicine, University of Genova, Genoa, Italy.
- IRCCS Ospedale Policlinico San Martino - IRCCS Italian Cardiovascular Network, Genoa, Italy.
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22
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Overexpression of mitochondrial creatine kinase preserves cardiac energetics without ameliorating murine chronic heart failure. Basic Res Cardiol 2020; 115:12. [PMID: 31925563 PMCID: PMC6954138 DOI: 10.1007/s00395-020-0777-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 01/02/2020] [Indexed: 01/24/2023]
Abstract
Mitochondrial creatine kinase (Mt-CK) is a major determinant of cardiac energetic status and is down-regulated in chronic heart failure, which may contribute to disease progression. We hypothesised that cardiomyocyte-specific overexpression of Mt-CK would mitigate against these changes and thereby preserve cardiac function. Male Mt-CK overexpressing mice (OE) and WT littermates were subjected to transverse aortic constriction (TAC) or sham surgery and assessed by echocardiography at 0, 3 and 6 weeks alongside a final LV haemodynamic assessment. Regardless of genotype, TAC mice developed progressive LV hypertrophy, dilatation and contractile dysfunction commensurate with pressure overload-induced chronic heart failure. There was a trend for improved survival in OE-TAC mice (90% vs 73%, P = 0.08), however, OE-TAC mice exhibited greater LV dilatation compared to WT and no functional parameters were significantly different under baseline conditions or during dobutamine stress test. CK activity was 37% higher in OE-sham versus WT-sham hearts and reduced in both TAC groups, but was maintained above normal values in the OE-TAC hearts. A separate cohort of mice received in vivo cardiac 31P-MRS to measure high-energy phosphates. There was no difference in the ratio of phosphocreatine-to-ATP in the sham mice, however, PCr/ATP was reduced in WT-TAC but preserved in OE-TAC (1.04 ± 0.10 vs 2.04 ± 0.22; P = 0.007). In conclusion, overexpression of Mt-CK activity prevented the changes in cardiac energetics that are considered hallmarks of a failing heart. This had a positive effect on early survival but was not associated with improved LV remodelling or function during the development of chronic heart failure.
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AlGhuraibawi W, Stromp T, Holtkamp R, Lam B, Rehwald W, Leung SW, Vandsburger M. CEST MRI reveals a correlation between visceral fat mass and reduced myocardial creatine in obese individuals despite preserved ventricular structure and function. NMR IN BIOMEDICINE 2019; 32:e4104. [PMID: 31094042 PMCID: PMC6581603 DOI: 10.1002/nbm.4104] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 03/19/2019] [Accepted: 03/20/2019] [Indexed: 05/29/2023]
Abstract
Systolic cardiac function is typically preserved in obese adults, potentially masking underlying declines in cardiomyocyte metabolism that may contribute to heart failure. We used chemical exchange saturation transfer (CEST) MRI, a sensitive method for measurement of myocardial creatine, to examine whether myocardial creatine levels correlate with cardiac structure, contractile function, or visceral fat mass in obese adults. In this study, obese (body mass index, BMI > 30, n = 20) and healthy (BMI < 25, n = 11) adults were examined with dual-energy x-ray absorptiometry to quantify fat masses. Cine MRI and myocardial tagging were performed at 1.5 T to measure ventricular structure and global function. CEST imaging with offsets in the range of ±10 parts per million (ppm) were performed in one mid-ventricular slice, where creatine CEST contrast was calculated at 1.8 ppm following field homogeneity correction. Ventricular structure, global function (ejection fraction 69.4 ± 4.3% healthy versus 69.6 ± 9.3% obese, NS), and circumferential strain (-17.0 ± 2.3% healthy versus -16.5 ± 1.5% obese, NS) and strain rate were preserved in obese adults. However, creatine CEST contrast was significantly reduced in obese adults (6.8 ± 1.3% healthy versus 4.1 ± 2.7% obese, p = 0.001). Creatine CEST contrast was inversely correlated with total body fat% (ρ = -0.45, p = 0.011), visceral fat mass (ρ = -0.58, p = 0.001), and septal wall thickness (ρ = -0.44, p = 0.013), but uncorrelated to ventricular function or contractile function. In conclusion, creatine CEST-MRI reveals a strong correlation between heightened body and visceral fat masses and reduced myocardial metabolic function that is independent of ventricular structure and global function in obese adults.
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Affiliation(s)
- Wissam AlGhuraibawi
- Department of Bioengineering, University of California Berkeley, Berkeley, California
| | - Tori Stromp
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, Kentucky
- GlaxoSmithKline Research and Development, Philadelphia, Pennsylvania
| | - Rebecca Holtkamp
- Saha Cardiovascular Research Center, University of Kentucky, Lexington, Kentucky
| | - Bonnie Lam
- Department of Bioengineering, University of California Berkeley, Berkeley, California
| | - Wolfgang Rehwald
- Siemens Medical Solutions USA, Inc. And Duke Cardiovascular MR Center, Durham, North Carolina
| | - Steve W. Leung
- Gill Heart and Vascular Institute, University of Kentucky, Lexington, Kentucky
| | - Moriel Vandsburger
- Department of Bioengineering, University of California Berkeley, Berkeley, California
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24
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Ellis J, Valkovič L, Purvis LA, Clarke WT, Rodgers CT. Reproducibility of human cardiac phosphorus MRS ( 31 P-MRS) at 7 T. NMR IN BIOMEDICINE 2019; 32:e4095. [PMID: 30924566 PMCID: PMC6546607 DOI: 10.1002/nbm.4095] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 02/11/2019] [Accepted: 02/20/2019] [Indexed: 05/12/2023]
Abstract
PURPOSE We test the reproducibility of human cardiac phosphorus MRS (31 P-MRS) at ultra-high field strength (7 T) for the first time. The primary motivation of this work was to assess the reproducibility of a 'rapid' 6½ min 31 P three-dimensional chemical shift imaging (3D-CSI) sequence, which if sufficiently reproducible would allow the study of stress-response processes. We compare this with an established 28 min protocol, designed to record high-quality spectra in a clinically feasible scan time. Finally, we use this opportunity to compare the effect of per-subject B0 shimming on data quality and reproducibility in the 6½ min protocol. METHODS 10 healthy subjects were scanned on two occasions: one to test the 28 min 3D-CSI protocol, and one to test the 6½ min protocol. Spectra were fitted using the OXSA MATLAB toolbox. The phosphocreatine to adenosine triphosphate concentration ratio (PCr/ATP) from each scan was analysed for intra- and intersubject variability. The impact of different strategies for voxel selection was assessed. RESULTS There were no significant differences between repeated measurements in the same subject. For the 28 min protocol, PCr/ATP in the midseptal voxel across all scans was 1.91 ± 0.36 (mean ± intersubject SD). For the 6½ min protocol, PCr/ATP in the midseptal voxel was 1.76 ± 0.40. The coefficients of reproducibility (CRs) were 0.49 (28 min) and 0.67 (6½ min). Per-subject B0 shimming improved the fitted PCr/ATP precision (for 6½ min scans), but had negligible effect on the CR (0.67 versus 0.66). CONCLUSIONS Both 7 T protocols show improved reproducibility compared with a previous 3 T study by Tyler et al. Our results will enable informed power calculations and protocol selection for future clinical research studies.
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Affiliation(s)
- Jane Ellis
- OCMR, RDM Cardiovascular MedicineUniversity of OxfordUK
| | - Ladislav Valkovič
- OCMR, RDM Cardiovascular MedicineUniversity of OxfordUK
- Slovak Academy of SciencesInstitute of Measurement ScienceBratislavaSlovakia
| | | | - William T. Clarke
- OCMR, RDM Cardiovascular MedicineUniversity of OxfordUK
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical NeurosciencesUniversity of OxfordUK
| | - Christopher T. Rodgers
- OCMR, RDM Cardiovascular MedicineUniversity of OxfordUK
- Wolfson Brain Imaging Centre, Department of Clinical NeurosciencesUniversity of CambridgeUK
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25
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Dolinsky VW. The role of sirtuins in mitochondrial function and doxorubicin-induced cardiac dysfunction. Biol Chem 2017; 398:955-974. [PMID: 28253192 DOI: 10.1515/hsz-2016-0316] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 02/11/2017] [Indexed: 01/15/2023]
Abstract
Anthracycline chemotherapeutics such as doxorubicin continue to be important treatments for many cancers. Through improved screening and therapy, more patients are surviving and living longer after the diagnosis of their cancer. However, anthracyclines are associated with both short- and long-term cardiotoxic effects. Doxorubicin-induced mitochondrial dysfunction is a central mechanism in the cardiotoxic effects of doxorubicin that contributes to impaired cardiac energy levels, increased reactive oxygen species production, cardiomyocyte apoptosis and the decline in cardiac function. Sirtuins are protein deacetylases that are activated by low energy levels and stimulate energy production through their activation of transcription factors and enzymatic regulators of cardiac energy metabolism. In addition, sirtuins activate oxidative stress resistance pathways. SIRT1 and SIRT3 are expressed at high levels in the cardiomyocyte. This review examines the function of sirtuins in the regulation of cardiac mitochondrial function, with a focus on their role in heart failure and an emphasis on their effects on doxorubicin-induced cardiotoxicity. We discuss the potential for sirtuin activation in combination with anthracycline chemotherapy in order to mitigate its cardiotoxic side-effects without reducing the antineoplastic activity of anthracyclines.
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26
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Brown DA, Perry JB, Allen ME, Sabbah HN, Stauffer BL, Shaikh SR, Cleland JGF, Colucci WS, Butler J, Voors AA, Anker SD, Pitt B, Pieske B, Filippatos G, Greene SJ, Gheorghiade M. Expert consensus document: Mitochondrial function as a therapeutic target in heart failure. Nat Rev Cardiol 2016; 14:238-250. [PMID: 28004807 PMCID: PMC5350035 DOI: 10.1038/nrcardio.2016.203] [Citation(s) in RCA: 455] [Impact Index Per Article: 56.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Heart failure is a pressing worldwide public-health problem with millions of patients having worsening heart failure. Despite all the available therapies, the condition carries a very poor prognosis. Existing therapies provide symptomatic and clinical benefit, but do not fully address molecular abnormalities that occur in cardiomyocytes. This shortcoming is particularly important given that most patients with heart failure have viable dysfunctional myocardium, in which an improvement or normalization of function might be possible. Although the pathophysiology of heart failure is complex, mitochondrial dysfunction seems to be an important target for therapy to improve cardiac function directly. Mitochondrial abnormalities include impaired mitochondrial electron transport chain activity, increased formation of reactive oxygen species, shifted metabolic substrate utilization, aberrant mitochondrial dynamics, and altered ion homeostasis. In this Consensus Statement, insights into the mechanisms of mitochondrial dysfunction in heart failure are presented, along with an overview of emerging treatments with the potential to improve the function of the failing heart by targeting mitochondria.
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Affiliation(s)
- David A Brown
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, 1035 Integrated Life Sciences Building, 1981 Kraft Drive, Blacksburg, Virginia 24060, USA
| | - Justin B Perry
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, 1035 Integrated Life Sciences Building, 1981 Kraft Drive, Blacksburg, Virginia 24060, USA
| | - Mitchell E Allen
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, 1035 Integrated Life Sciences Building, 1981 Kraft Drive, Blacksburg, Virginia 24060, USA
| | - Hani N Sabbah
- Division of Cardiovascular Medicine, Department of Medicine, Henry Ford Hospital, 2799 West Grand Boulevard, Detroit, Michigan 48202, USA
| | - Brian L Stauffer
- Division of Cardiology, Department of Medicine, University of Colorado Denver, 12700 East 19th Avenue, B139, Aurora, Colorado 80045, USA
| | - Saame Raza Shaikh
- Department of Biochemistry and Molecular Biology, East Carolina Diabetes and Obesity Institute, Brody School of Medicine, East Carolina University, 115 Heart Drive, Greenville, North Carolina 27834, USA
| | - John G F Cleland
- National Heart &Lung Institute, National Institute of Health Research Cardiovascular Biomedical Research Unit, Royal Brompton &Harefield Hospitals, Imperial College, London, UK
| | - Wilson S Colucci
- Cardiovascular Medicine Section, Boston University School of Medicine and Boston Medical Center, 88 East Newton Street, C-8, Boston, Massachusetts 02118, USA
| | - Javed Butler
- Division of Cardiology, Health Sciences Center, T-16 Room 080, SUNY at Stony Brook, New York 11794, USA
| | - Adriaan A Voors
- University of Groningen, Department of Cardiology, University Medical Center Groningen, Groningen 9713 GZ, Netherlands
| | - Stefan D Anker
- Department of Innovative Clinical Trials, University Medical Centre Göttingen (UMG), Robert-Koch-Straße, D-37075, Göttingen, Germany
| | - Bertram Pitt
- University of Michigan School of Medicine, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109, USA
| | - Burkert Pieske
- Department of Cardiology, Charité University Medicine, Campus Virchow Klinikum, and German Heart Center Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Gerasimos Filippatos
- National and Kopodistrian University of Athens, School of Medicine, Heart Failure Unit, Department of Cardiology, Athens University Hospital Attikon, Rimini 1, Athens 12462, Greece
| | - Stephen J Greene
- Division of Cardiology, Duke University Medical Center, 2301 Erwin Road Suite 7400, Durham, North Carolina 27705, USA
| | - Mihai Gheorghiade
- Center for Cardiovascular Innovation, Northwestern University Feinberg School of Medicine, 201 East Huron, Galter 3-150, Chicago, Illinois 60611, USA
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27
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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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28
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Slingo M, Cole M, Carr C, Curtis MK, Dodd M, Giles L, Heather LC, Tyler D, Clarke K, Robbins PA. The von Hippel-Lindau Chuvash mutation in mice alters cardiac substrate and high-energy phosphate metabolism. Am J Physiol Heart Circ Physiol 2016; 311:H759-67. [PMID: 27422990 PMCID: PMC5142182 DOI: 10.1152/ajpheart.00912.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 07/12/2016] [Indexed: 02/07/2023]
Abstract
This is the first integrative metabolic and functional study of the effects of modest hypoxia-inducible factor manipulation within the heart. Of particular note, the combination (and correlation) of perfused heart metabolic flux measurements with the new technique of real-time in vivo magnetic resonance spectroscopy using hyperpolarized pyruvate is a novel development. Hypoxia-inducible factor (HIF) appears to function as a global master regulator of cellular and systemic responses to hypoxia. HIF pathway manipulation is of therapeutic interest; however, global systemic upregulation of HIF may have as yet unknown effects on multiple processes. We used a mouse model of Chuvash polycythemia (CP), a rare genetic disorder that modestly increases expression of HIF target genes in normoxia, to understand what these effects might be within the heart. An integrated in and ex vivo approach was employed. Compared with wild-type controls, CP mice had evidence (using in vivo magnetic resonance imaging) of pulmonary hypertension, right ventricular hypertrophy, and increased left ventricular ejection fraction. Glycolytic flux (measured using [3H]glucose) in the isolated contracting perfused CP heart was 1.8-fold higher. Net lactate efflux was 1.5-fold higher. Furthermore, in vivo 13C-magnetic resonance spectroscopy (MRS) of hyperpolarized [13C1]pyruvate revealed a twofold increase in real-time flux through lactate dehydrogenase in the CP hearts and a 1.6-fold increase through pyruvate dehydrogenase. 31P-MRS of perfused CP hearts under increased workload (isoproterenol infusion) demonstrated increased depletion of phosphocreatine relative to ATP. Intriguingly, no changes in cardiac gene expression were detected. In summary, a modest systemic dysregulation of the HIF pathway resulted in clear alterations in cardiac metabolism and energetics. However, in contrast to studies generating high HIF levels within the heart, the CP mice showed neither the predicted changes in gene expression nor any degree of LV impairment. We conclude that the effects of manipulating HIF on the heart are dose dependent.
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Affiliation(s)
- Mary Slingo
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Mark Cole
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Carolyn Carr
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Mary K Curtis
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Michael Dodd
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Lucia Giles
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Lisa C Heather
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Damian Tyler
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Kieran Clarke
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
| | - Peter A Robbins
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom
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29
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Stoll VM, Clarke WT, Levelt E, Liu A, Myerson SG, Robson MD, Neubauer S, Rodgers CT. Dilated Cardiomyopathy: Phosphorus 31 MR Spectroscopy at 7 T. Radiology 2016; 281:409-417. [PMID: 27326664 PMCID: PMC5084974 DOI: 10.1148/radiol.2016152629] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Cardiac phosphorus spectroscopy is demonstrated to be feasible in patients at 7 T,
giving higher signal-to-noise ratios and more precise quantification of the
phosphocreatine to adenosine triphosphate concentration ratio than at 3 T in a group
of 25 patients with dilated cardiomyopathy. Purpose To test whether the increased signal-to-noise ratio of phosphorus 31
(31P) magnetic resonance (MR) spectroscopy at 7 T improves precision
in cardiac metabolite quantification in patients with dilated cardiomyopathy (DCM)
compared with that at 3 T. Materials and Methods Ethical approval was obtained, and participants provided written informe consent.
In a prospective study, 31P MR spectroscopy was performed at 3 T and 7
T in 25 patients with DCM. Ten healthy matched control subjects underwent
31P MR spectroscopy at 7 T. Paired Student t tests
were performed to compare results between the 3-T and 7-T studies. Results The phosphocreatine (PCr) signal-to-noise ratio increased 2.5 times at 7 T
compared with that at 3 T. The PCr to adenosine triphosphate (ATP) concentration
ratio (PCr/ATP) was similar at both field strengths (mean ± standard
deviation, 1.48 ± 0.44 at 3 T vs 1.54 ± 0.39 at 7 T, P
= .49), as expected. The Cramér-Rao lower bounds in PCr concentration (a
measure of uncertainty in the measured ratio) were 45% lower at 7 T than at 3 T,
reflecting the higher quality of 7-T 31P spectra. Patients with dilated
cardioyopathy had a significantly lower PCr/ATP than did healthy control subjects
at 7 T (1.54 ± 0.39 vs 1.95 ± 0.25, P = .005),
which is consistent with previous findings. Conclusion 7-T cardiac 31P MR spectroscopy is feasible in patients with DCM and
gives higher signal-to-noise ratios and more precise quantification of the PCr/ATP
than that at 3 T. PCr/ATP was significantly lower in patients with DCM than in
control subjects at 7 T, which is consistent with previous findings at lower field
strengths.
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Affiliation(s)
- Victoria M Stoll
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - William T Clarke
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - Eylem Levelt
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - Alexander Liu
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - Saul G Myerson
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - Matthew D Robson
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - Stefan Neubauer
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
| | - Christopher T Rodgers
- From the Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Level 0, John Radcliffe Hospital, Oxford OX3 9DU, England
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30
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Marcinkiewicz-Siemion M, Ciborowski M, Kretowski A, Musial WJ, Kaminski KA. Metabolomics - A wide-open door to personalized treatment in chronic heart failure? Int J Cardiol 2016; 219:156-63. [PMID: 27323342 DOI: 10.1016/j.ijcard.2016.06.022] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 06/12/2016] [Indexed: 12/29/2022]
Abstract
Heart failure (HF) is a complex syndrome representing a final stage of various cardiovascular diseases. Despite significant improvement in the diagnosis and treatment (e.g. ACE-inhibitors, β-blockers, aldosterone antagonists, cardiac resynchronization therapy) of the disease, prognosis of optimally treated patients remains very serious and HF mortality is still unacceptably high. Therefore there is a strong need for further exploration of novel analytical methods, predictive and prognostic biomarkers and more personalized treatment. The metabolism of the failing heart being significantly impaired from its baseline state may be a future target not only for biomarker discovery but also for the pharmacologic intervention. However, an assessment of a particular, isolated metabolite or protein cannot be fully informative and makes a correct interpretation difficult. On the other hand, metabolites profile analysis may greatly assist investigator in an interpretation of the altered pathway dynamics, especially when combined with other lines of evidence (e.g. metabolites from the same pathway, transcriptomics, proteomics). Despite many prior studies on metabolism, the knowledge of peripheral and cardiac pathophysiological mechanisms responsible for the metabolic imbalance and progression of the disease is still insufficient. Metabolomics enabling comprehensive characterization of low molecular weight metabolites (e.g. lipids, sugars, organic acids, amino acids) that reflects the complete metabolic phenotype seems to be the key for further potential improvement in HF treatment (diet-based or biochemical-based). Will this -omics technique one day open a door to easy patients identification before they have a heart failure onset or its decompensation?
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Affiliation(s)
| | - M Ciborowski
- Clinical Research Centre, Medical University of Bialystok, Poland
| | - A Kretowski
- Clinical Research Centre, Medical University of Bialystok, Poland
| | - W J Musial
- Cardiology Department, University Hospital, Bialystok, Poland
| | - K A Kaminski
- Cardiology Department, University Hospital, Bialystok, Poland; Department of Population Medicine and Civilization Disease Prevention, Medical University of Bialystok, Poland.
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31
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Rayner JJ, Neubauer S, Rider OJ. The paradox of obesity cardiomyopathy and the potential for weight loss as a therapy. Obes Rev 2015; 16:679-90. [PMID: 26096833 DOI: 10.1111/obr.12292] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/08/2015] [Accepted: 04/23/2015] [Indexed: 12/18/2022]
Abstract
Obesity is an independent risk factor for developing heart failure and the combination of the two disease states will prove to be a significant health burden over the coming years. Obesity is likely to contribute to the development of heart failure through a variety of mechanisms, including structural and functional changes, lipotoxicity and steatosis and altered substrate selection. However, once heart failure has developed, it seems that obesity confers a beneficial influence on prognosis in what has been termed the 'obesity paradox'. This may be a statistical phenomenon, but it should be considered that there is truly a protective state in the physiology of obesity. There is little evidence regarding the impact of weight loss in obese heart failure and whether or not this is beneficial. There have been small studies regarding the cardiovascular effects of both dietary weight loss and bariatric surgery, but few in heart failure. This is an important and increasingly relevant clinical question which must be addressed.
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Affiliation(s)
- J J Rayner
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - S Neubauer
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
| | - O J Rider
- Oxford Centre for Clinical Magnetic Resonance Research, Radcliffe Department of Medicine, Division of Cardiovascular Medicine, University of Oxford, Oxford, UK
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Kundu BK, Zhong M, Sen S, Davogustto G, Keller SR, Taegtmeyer H. Remodeling of glucose metabolism precedes pressure overload-induced left ventricular hypertrophy: review of a hypothesis. Cardiology 2015; 130:211-20. [PMID: 25791172 DOI: 10.1159/000369782] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 11/10/2014] [Indexed: 12/14/2022]
Abstract
When subjected to pressure overload, the ventricular myocardium shifts from fatty acids to glucose as its main source for energy provision and frequently increases its mass. Here, we review the evidence in support of the concept that metabolic remodeling, measured as an increased myocardial glucose uptake using dynamic positron emission tomography (PET) with the glucose analogue 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG), precedes the onset of left ventricular hypertrophy (LVH) and heart failure. Consistent with this, early intervention with propranolol, which attenuates glucose uptake, prevents the maladaptive metabolic response and preserves cardiac function in vivo. We also review ex vivo studies suggesting a link between dysregulated myocardial glucose metabolism, intracellular accumulation of glucose 6-phosphate (G6P) and contractile dysfunction of the heart. G6P levels correlate with activation of mTOR (mechanistic target of rapamycin) and endoplasmic reticulum stress. This sequence of events could be prevented by pretreatment with rapamycin (mTOR inhibition) or metformin (enzyme 5'-AMP-activated protein kinase activation). In conclusion, we propose that metabolic imaging with FDG PET may provide a novel approach to guide the treatment of patients with hypertension-induced LVH.
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Affiliation(s)
- Bijoy K Kundu
- Department of Radiology and Medical Imaging, University of Virginia, Charlottesville, Va., USA
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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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Rider OJ, Francis JM, Ali MK, Holloway C, Pegg T, Robson MD, Tyler D, Byrne J, Clarke K, Neubauer S. Effects of catecholamine stress on diastolic function and myocardial energetics in obesity. Circulation 2012; 125:1511-9. [PMID: 22368152 DOI: 10.1161/circulationaha.111.069518] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Obesity is characterized by impaired cardiac energetics, which may play a role in the development of diastolic dysfunction and inappropriate shortness of breath. We assessed whether, in obesity, derangement of energetics and diastolic function is further altered during acute cardiac stress. METHODS AND RESULTS Normal-weight (body mass index, 22±2 kg/m(2); n=9-17) and obese (body mass index, 39±7 kg/m(2); n=17-46) subjects underwent assessment of diastolic left ventricular function (cine magnetic resonance imaging volume-time curve analysis) and cardiac energetics (phosphocreatine/ATP ratio; (31)P-magnetic resonance spectroscopy) at rest and during dobutamine stress (heart rate increase, 65±22% and 69±14%, respectively; P=0.61). At rest, obesity was associated with a 22% lower peak filling rate (P<0.001) and a 15% lower phosphocreatine/ATP ratio (1.73±0.40 versus 2.03±0.28; P=0.048). Peak filling rate correlated with fat mass, left ventricular mass, leptin, waist-to-hip ratio, and phosphocreatine/ATP ratio. On multivariable analysis, phosphocreatine/ATP was the only independent predictor of peak filling rate (β=0.50; P=0.03). During stress, a further reduction in phosphocreatine/ATP occurred in obese (from 1.73±0.40 to 1.53±0.50; P=0.03) but not in normal-weight (from 1.98±0.24 to 2.04±0.34; P=0.50) subject. For similar levels of inotropic stress, there were smaller increases in peak filling rate in obesity (38% versus 70%; P=0.01). CONCLUSIONS In obesity, cardiac energetics are further deranged during inotropic stress, in association with continued diastolic dysfunction. Myocardial energetics may play a key role in the impairment of diastolic function in obesity.
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Affiliation(s)
- Oliver J Rider
- Department of Cardiovascular Medicine, John Radcliffe Hospital, Oxford, UK.
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Abstract
Cardiac magnetic resonance spectroscopy (MRS) is a noninvasive tool for the assessment of myocardial metabolism, without the use of radiation or intravenous contrast agents. Using the intrinsic magnetic resonance signals from nuclei, including (31)Phosphorus, (1)Hydrogen, (23)Sodium, and (13)Carbon and, more recently, hyperpolarization techniques, MRS provides a comprehensive metabolic assessment of cardiac muscle. This highly versatile technique has provided insights into the pathophysiology of cardiac metabolism in a wide range of conditions, including ischemic heart disease, heart failure, genetic cardiomyopathies, heart transplantation, hypertensive heart disease, valvular heart disease, and diabetes. In addition, MRS has value in the assessment of prognosis and for monitoring therapeutic strategies in heart failure. However, because of the low temporal and spatial resolution of the technique, MRS has so far been limited to research applications. With higher field strength magnets and novel hyperpolarization techniques, the promise of using MRS for clinical applications may eventually be fulfilled.
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Affiliation(s)
- Cameron J Holloway
- Department of Cardiovascular Medicine, The University of Oxford Centre for Clinical Magnetic Resonance Research, University of Oxford, UK.
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Abstract
Being independent of coronary artery disease and hypertension, diabetic cardiomyopathy is a distinct primary disease process, which precedes the development of congestive heart failure. Epidemiologic as well as clinical studies confirmed the close link between diabetes mellitus and heart failure. Altered cardiac structure and function are common diagnoses in patients with type 2 diabetes mellitus. Hyperglycemia leading to the formation of advanced glycation end products and hyperlipidemia resulting in lipotoxicity are of structural and functional impact on cardiac muscle and cardiomyocytes. New and more sensitive methods of diagnosis identify early diastolic dysfunction as a precursor of the development of congestive heart failure. This review focuses on the mechanistic approach to understand the molecular basis of diabetic cardiomyopathy in patients with type 2 diabetes mellitus.
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Affiliation(s)
- Bernd Stratmann
- Heart and Diabetes Center NRW, Ruhr, University of Bochum, Bochum, Germany
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Seppet E, Gruno M, Peetsalu A, Gizatullina Z, Nguyen HP, Vielhaber S, Wussling MH, Trumbeckaite S, Arandarcikaite O, Jerzembeck D, Sonnabend M, Jegorov K, Zierz S, Striggow F, Gellerich FN. Mitochondria and energetic depression in cell pathophysiology. Int J Mol Sci 2009; 10:2252-2303. [PMID: 19564950 PMCID: PMC2695278 DOI: 10.3390/ijms10052252] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2009] [Revised: 04/25/2009] [Accepted: 05/14/2009] [Indexed: 12/21/2022] Open
Abstract
Mitochondrial dysfunction is a hallmark of almost all diseases. Acquired or inherited mutations of the mitochondrial genome DNA may give rise to mitochondrial diseases. Another class of disorders, in which mitochondrial impairments are initiated by extramitochondrial factors, includes neurodegenerative diseases and syndromes resulting from typical pathological processes, such as hypoxia/ischemia, inflammation, intoxications, and carcinogenesis. Both classes of diseases lead to cellular energetic depression (CED), which is characterized by decreased cytosolic phosphorylation potential that suppresses the cell's ability to do work and control the intracellular Ca(2+) homeostasis and its redox state. If progressing, CED leads to cell death, whose type is linked to the functional status of the mitochondria. In the case of limited deterioration, when some amounts of ATP can still be generated due to oxidative phosphorylation (OXPHOS), mitochondria launch the apoptotic cell death program by release of cytochrome c. Following pronounced CED, cytoplasmic ATP levels fall below the thresholds required for processing the ATP-dependent apoptotic cascade and the cell dies from necrosis. Both types of death can be grouped together as a mitochondrial cell death (MCD). However, there exist multiple adaptive reactions aimed at protecting cells against CED. In this context, a metabolic shift characterized by suppression of OXPHOS combined with activation of aerobic glycolysis as the main pathway for ATP synthesis (Warburg effect) is of central importance. Whereas this type of adaptation is sufficiently effective to avoid CED and to control the cellular redox state, thereby ensuring the cell survival, it also favors the avoidance of apoptotic cell death. This scenario may underlie uncontrolled cellular proliferation and growth, eventually resulting in carcinogenesis.
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Affiliation(s)
- Enn Seppet
- Department of Pathophysiology, University of Tartu, Tartu, Estonia; E-Mail:
(M.G.)
| | - Marju Gruno
- Department of Pathophysiology, University of Tartu, Tartu, Estonia; E-Mail:
(M.G.)
| | - Ants Peetsalu
- Department of Surgery, University of Tartu, Tartu, Estonia; E-Mail:
(A.P.)
| | - Zemfira Gizatullina
- KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany; E-Mails:
(Z.G.);
(D.J.);
(M.S.);
(K.J.);
(F.S.);
(F.N.G.)
| | - Huu Phuc Nguyen
- Department of Medical Genetics, University of Tübingen, Tübingen, Germany; E-Mail:
(H.P.N.)
| | - Stefan Vielhaber
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany; E-Mail:
(S.V.)
| | - Manfred H.P. Wussling
- Bernstein Institute for Physiology, Martin-Luther-University Halle-Wittenberg, Germany; E-Mail:
(M.H.P.W.)
| | - Sonata Trumbeckaite
- Institute for Biomedical Research, Kaunas University of Medicine, Kaunas, Lithuania; E-Mails:
(S.T.);
(O.A.)
| | - Odeta Arandarcikaite
- Institute for Biomedical Research, Kaunas University of Medicine, Kaunas, Lithuania; E-Mails:
(S.T.);
(O.A.)
| | - Doreen Jerzembeck
- KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany; E-Mails:
(Z.G.);
(D.J.);
(M.S.);
(K.J.);
(F.S.);
(F.N.G.)
| | - Maria Sonnabend
- KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany; E-Mails:
(Z.G.);
(D.J.);
(M.S.);
(K.J.);
(F.S.);
(F.N.G.)
| | - Katharina Jegorov
- KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany; E-Mails:
(Z.G.);
(D.J.);
(M.S.);
(K.J.);
(F.S.);
(F.N.G.)
| | - Stephan Zierz
- Department of Neurology, Martin-Luther-University Halle-Wittenberg, Germany; E-Mail:
(S.Z.)
| | - Frank Striggow
- KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany; E-Mails:
(Z.G.);
(D.J.);
(M.S.);
(K.J.);
(F.S.);
(F.N.G.)
| | - Frank N. Gellerich
- KeyNeurotek AG, ZENIT-Technology Park Magdeburg, Magdeburg, Germany; E-Mails:
(Z.G.);
(D.J.);
(M.S.);
(K.J.);
(F.S.);
(F.N.G.)
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Hudsmith LE, Neubauer S. Magnetic Resonance Spectroscopy in Myocardial Disease. JACC Cardiovasc Imaging 2009; 2:87-96. [DOI: 10.1016/j.jcmg.2008.08.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Accepted: 08/06/2008] [Indexed: 10/21/2022]
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Detection of myocardial disorders by magnetic resonance spectroscopy. ACTA ACUST UNITED AC 2008; 5 Suppl 2:S49-56. [DOI: 10.1038/ncpcardio1158] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2007] [Accepted: 12/14/2007] [Indexed: 11/08/2022]
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40
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Eisen HJ. Exercise Training and Myocardial Energetics in Patients With Heart Failure. J Am Coll Cardiol 2008; 51:1892-5. [DOI: 10.1016/j.jacc.2008.02.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 02/08/2008] [Indexed: 10/22/2022]
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Abstract
Magnetic resonance spectroscopy (MRS) allows for the non-invasive detection of a wide variety of metabolites in the heart. To study the metabolic changes that occur in heart failure, (31)P- and (1)H-MRS have been applied in both patients and experimental animal studies. (31)P-MRS allows for the detection of phosphocreatine (PCr), ATP, inorganic phosphate (Pi) and intracellular pH, while (1)H-MRS allows for the detection of total creatine. All these compounds are involved in the regulation of the available energy from ATP hydrolysis via the creatine kinase (CK) reaction. Using cardiac MRS, it has been found that the PCr/CK system is impaired in the failing heart. In both, patients and experimental models, PCr levels as well as total creatine levels are reduced, and in severe heart failure ATP is also reduced. PCr/ATP ratios correlate with the clinical severity of heart failure and, importantly, are a prognostic indicator of mortality in patients. In addition, the chemical flux through the CK reaction, measured with (31)P saturation transfer MRS, is reduced more than the steady-state levels of high-energy phosphates in failing myocardium in both experimental models and in patients. Experimental studies suggest that these changes can result in increased free ADP levels when the failing heart is stressed. Increased free ADP levels, in turn, result in a reduction in the available free energy of ATP hydrolysis, which may directly contribute to contractile dysfunction. Data from transgenic mouse models also suggest that an intact creatine/CK system is critical for situations of cardiac stress.
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Affiliation(s)
- Michiel Ten Hove
- Department of Cardiovascular Medicine, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, OX3 7BN, UK.
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42
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Affiliation(s)
- Stefan Neubauer
- Department of Cardiovascular Medicine, University of Oxford and John Radcliffe Hospital, Oxford, United Kingdom.
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43
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Abstract
Viruses are the most common cause of myocarditis in economically advanced countries. Enteroviruses and adenoviruses are the most common etiologic agents. Viral myocarditis is a triphasic process. Phase 1 is the period of active viral replication in the myocardium during which the symptoms of myocardial damage range from none to cardiogenic shock. If the disease process continues, it enters phase 2, which is characterized by autoimmunity triggered by viral and myocardial proteins. Heart failure often appears for the first time in phase 2. Phase 3, dilated cardiomyopathy, is the end result in some patients. Diagnostic procedures and treatment should be tailored to the phase of disease. Viral myocarditis is a significant cause of dilated cardiomyopathy, as proved by the frequent presence of viral genomic material in the myocardium, and by improvement in ventricular function by immunomodulatory therapy. Myocarditis of any etiology usually presents with heart failure, but the second most common presentation is ventricular arrhythmia. As a result, myocarditis is one of the most common causes of sudden death in young people and others without preexisting structural heart disease. Myocarditis can be definitively diagnosed by endomyocardial biopsy. However, it is clear that existing criteria for the histologic diagnosis need to be refined, and that a variety of molecular markers in the myocardium and the circulation can be used to establish the diagnosis. Treatment of myocarditis has been generally disappointing. Accurate staging of the disease will undoubtedly improve treatment in the future. It is clear that immunosuppression and immunomodulation are effective in some patients, especially during phase 2, but may not be as useful in phases 1 and 3. Since myocarditis is often selflimited, bridging and recovery therapy with circulatory assistance may be effective. Prevention by immunization or receptor blocking strategies is under development. Giant cell myocarditis is an unusually fulminant form of the disease that progresses rapidly to heart failure or sudden death. Rapid onset of disease in young people, especially those with other autoimmune manifestations, accompanied by heart failure or ventricular arrhythmias, suggests giant cell myocarditis. Peripartum cardiomyopathy in economically developed countries is usually the result of myocarditis.
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Affiliation(s)
- James T. Willerson
- The University of Texas Health Science Center in Houston, Houston, ,Texas Heart Institute, Houston, TX USA
| | - Hein J. J. Wellens
- Department of Cardiology, University of Maastricht, Masstricht, The Netherlands
| | - Jay N. Cohn
- Rasmussen Center for Cardiovascular Disease Prevention Cardiovascular Division, University of Minnesota, Minneapolis, MN USA
| | - David R. Holmes
- Cardiovascular Medicine, Mayo Clinic College of Medicine, Rochester, MN USA
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Fowler SJ, Narula J, Gurudevan SV. Review of Noninvasive Imaging for Hypertrophic Cardiac Syndromes and Restrictive Physiology. Heart Fail Clin 2006; 2:215-30. [PMID: 17386891 DOI: 10.1016/j.hfc.2006.04.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Cha YM, Dzeja PP, Redfield MM, Shen WK, Terzic A. Bioenergetic protection of failing atrial and ventricular myocardium by vasopeptidase inhibitor omapatrilat. Am J Physiol Heart Circ Physiol 2005; 290:H1686-92. [PMID: 16339841 DOI: 10.1152/ajpheart.00384.2005] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Deficient bioenergetic signaling contributes to myocardial dysfunction and electrical instability in both atrial and ventricular cardiac chambers. Yet, approaches capable to prevent metabolic distress are only partially established. Here, in a canine model of tachycardia-induced congestive heart failure, we compared atrial and ventricular bioenergetics and tested the efficacy of metabolic rescue with the vasopeptidase inhibitor omapatrilat. Despite intrinsic differences in energy metabolism, failing atria and ventricles demonstrated profound bioenergetic deficiency with reduced ATP and creatine phosphate levels and compromised adenylate kinase and creatine kinase catalysis. Depressed phosphotransfer enzyme activities correlated with reduced tissue ATP levels, whereas creatine phosphate inversely related with atrial and ventricular load. Chronic treatment with omapatrilat maintained myocardial ATP, the high-energy currency, and protected adenylate and creatine kinase phosphotransfer capacity. Omapatrilat-induced bioenergetic protection was associated with maintained atrial and ventricular structural integrity, albeit without full recovery of the creatine phosphate pool. Thus therapy with omapatrilat demonstrates the benefit in protecting phosphotransfer enzyme activities and in preventing impairment of atrial and ventricular bioenergetics in heart failure.
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Affiliation(s)
- Yong-Mei Cha
- Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA
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Abstract
There is compelling evidence that alterations in myocardial substrate use play a key role in a variety of normal and abnormal cardiac conditions such as aging, left ventricular hypertrophy, and diabetic heart disease. However, it is unclear whether the metabolic changes are adaptive or maladaptive. Development of transgenic models targeting key aspects of myocardial substrate use, such as uptake, oxidation, and storage, is accelerating our understanding of the metabolic perturbations of cardiac disease. However, whether the metabolic phenotype in these models is relevant to the human condition is frequently unknown. The importance of altered myocardial metabolism in the pathogenesis of cardiac disease is underscored by the current robust development of novel therapeutics that target myocardial substrate use. Currently, magnetic resonance spectroscopy, single photon emission computed tomography, and positron emission tomography are the 3 methods available to image myocardial substrate metabolism. In this review the role of metabolic imaging in the study of specific cardiac disease processes will be discussed. Both the current and future capabilities of metabolic imaging to furthering our understanding of cardiac disease are highlighted.
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Affiliation(s)
- Pilar Herrero
- Division of Radiological Sciences, Mallinckrodt Institute of Radiology, St Louis, MO 63110, USA
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Nakae I, Mitsunami K, Matsuo S, Inubushi T, Morikawa S, Tsutamoto T, Koh T, Horie M. Myocardial Creatine Concentration in Various Nonischemic Heart Diseases Assessed by 1H Magnetic Resonance Spectroscopy. Circ J 2005; 69:711-6. [PMID: 15914951 DOI: 10.1253/circj.69.711] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Previous (31)P magnetic resonance spectroscopy (MRS) studies demonstrated that the myocardial phosphocreatine-to-ATP ratio offered important information concerning the degree of dysfunction and prognosis in patients with cardiomyopathy. In the present study, we investigated total creatine (CR) levels in various diseased hearts using 1H MRS. METHODS AND RESULTS Fourteen patients with the following conditions were examined: cardiac amyloidosis (n = 2); hypertensive heart disease (4); valvular disease (2); hypertrophic cardiomyopathy (2); dilated cardiomyopathy (2); restrictive cardiomyopathy (1); and post-operative atrial septal defect (1). Myocardial CR was measured using 1H MRS with point-resolved spectroscopy localization. Overall, myocardial CR levels in diseased hearts were significantly lower than those in the control group [16.5+/-6.0 (n = 14) vs 27.1+/-3.2 micromol/g (n = 10), p < 0.001]. There was a positive correlation between myocardial CR and left ventricular ejection fraction (42.9+/-13.8%, range 19.5-69.1%) despite the different mechanisms of cardiac dysfunction (r = 0.60, p < 0.05). Myocardial CR levels in patients who were hospitalized due to heart failure within 1 year were significantly lower than those in other patients [11.3+/-1.0 (n = 4) vs 18.6+/-5.9 micromol/g (n = 10), p < 0.05]. CONCLUSIONS Noninvasive measurement of myocardial CR using 1H MRS may be valuable in the assessment of disease severity and prediction of clinical course in various forms of heart disease.
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Affiliation(s)
- Ichiro Nakae
- Department of Cardiovascular and Respiratory Medicine, Shiga University of Medical Science, Otsu, Japan
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Abstract
ATP-binding cassette (ABC) transporters are multidomain integral membrane proteins that utilise the energy of ATP hydrolysis to translocate solutes across cellular membranes in all phyla. ABC transporters form one of the largest of all protein families and are central to many important biomedical phenomena, including resistance of cancers and pathogenic microbes to drugs. Elucidation of the structure and mechanism of ABC transporters is essential to the rational design of agents to control their function. While a wealth of high-resolution structures of ABC proteins have been produced in recent years, many fundamental questions regarding the protein's mechanism remain unanswered. In this review, we examine the recent structural data concerning ABC transporters and related proteins in the light of other experimental and theoretical data, and discuss these data in relation to current ideas concerning the transporters' molecular mechanism.
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Affiliation(s)
- P. M. Jones
- Department of Cell and Molecular Biology, University of Technology Sydney, Broadway, 2007 Sydney, Australia
| | - A. M. George
- Department of Cell and Molecular Biology, University of Technology Sydney, Broadway, 2007 Sydney, Australia
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50
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Nakae I, Mitsunami K, Matsuo S, Matsumoto T, Morikawa S, Inubushi T, Koh T, Horie M. Assessment of Myocardial Creatine Concentration in Dysfunctional Human Heart by Proton Magnetic Resonance Spectroscopy. Magn Reson Med Sci 2004; 3:19-25. [PMID: 16093616 DOI: 10.2463/mrms.3.19] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Creatine depletion in the non-viable infarcted human heart was previously demonstrated with proton magnetic resonance (MR) spectroscopy (1H MRS). In the present study, we assessed total creatine (CR) in human hearts with non-ischemic dysfunctions such as cardiomyopathy. Using cardiac-gated 1H MRS with MR image-guided PRESS localization, we measured septal CR in healthy and diseased human hearts. Fifteen patients with chronic heart failure (CHF, left ventricular ejection fraction < 45%) and 14 age-matched normal subjects were examined. Myocardial CR was significantly (p < 0.001) lower in failing hearts (15.1+/-SD 5.0 micromol/g wet weight, range 8.0-22.9) than in normal hearts (27.6+/-4.1 micromol/g wet weight, range 20.8-36.2). Myocardial CR concentrations in six heart failure patients with plasma B-type natriuretic peptide (BNP) levels of > 200 pg/ml (11.5+/-0.9 micromol/g wet weight, range 9.9-12.3) were significantly lower than those in four heart failure patients with plasma BNP levels of < 200 pg/ml (19.8+/-2.5 micromol/g wet weight, range 17.7-22.9, p < 0.001). Thus, our study showed that myocardial CR was decreased in non-ischemic dysfunctional hearts. Noninvasive measurements of myocardial CR by 1H MRS may be useful in the assessment of the severity of heart failure.
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Affiliation(s)
- Ichiro Nakae
- Department of Cardiovascular and Respiratory Medicine, Shiga University of Medical Science, Seta, otsu, Japan
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