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Emerging Therapy for Diabetic Cardiomyopathy: From Molecular Mechanism to Clinical Practice. Biomedicines 2023; 11:biomedicines11030662. [PMID: 36979641 PMCID: PMC10045486 DOI: 10.3390/biomedicines11030662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 02/08/2023] [Accepted: 02/11/2023] [Indexed: 02/24/2023] Open
Abstract
Diabetic cardiomyopathy is characterized by abnormal myocardial structure or performance in the absence of coronary artery disease or significant valvular heart disease in patients with diabetes mellitus. The spectrum of diabetic cardiomyopathy ranges from subtle myocardial changes to myocardial fibrosis and diastolic function and finally to symptomatic heart failure. Except for sodium–glucose transport protein 2 inhibitors and possibly bariatric and metabolic surgery, there is currently no specific treatment for this distinct disease entity in patients with diabetes. The molecular mechanism of diabetic cardiomyopathy includes impaired nutrient-sensing signaling, dysregulated autophagy, impaired mitochondrial energetics, altered fuel utilization, oxidative stress and lipid peroxidation, advanced glycation end-products, inflammation, impaired calcium homeostasis, abnormal endothelial function and nitric oxide production, aberrant epidermal growth factor receptor signaling, the activation of the renin–angiotensin–aldosterone system and sympathetic hyperactivity, and extracellular matrix accumulation and fibrosis. Here, we summarize several important emerging treatments for diabetic cardiomyopathy targeting specific molecular mechanisms, with evidence from preclinical studies and clinical trials.
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Asfaw TN, Bondarenko VE. A compartmentalized mathematical model of the β 1- and β 2-adrenergic signaling systems in ventricular myocytes from mouse in heart failure. Am J Physiol Cell Physiol 2023; 324:C263-C291. [PMID: 36468844 DOI: 10.1152/ajpcell.00366.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mouse models of heart failure are extensively used to research human cardiovascular diseases. In particular, one of the most common is the mouse model of heart failure resulting from transverse aortic constriction (TAC). Despite this, there are no comprehensive compartmentalized mathematical models that describe the complex behavior of the action potential, [Ca2+]i transients, and their regulation by β1- and β2-adrenergic signaling systems in failing mouse myocytes. In this paper, we develop a novel compartmentalized mathematical model of failing mouse ventricular myocytes after TAC procedure. The model describes well the cell geometry, action potentials, [Ca2+]i transients, and β1- and β2-adrenergic signaling in the failing cells. Simulation results obtained with the failing cell model are compared with those from the normal ventricular myocytes. Exploration of the model reveals the sarcoplasmic reticulum Ca2+ load mechanisms in failing ventricular myocytes. We also show a larger susceptibility of the failing myocytes to early and delayed afterdepolarizations and to a proarrhythmic behavior of Ca2+ dynamics upon stimulation with isoproterenol. The mechanisms of the proarrhythmic behavior suppression are investigated and sensitivity analysis is performed. The developed model can explain the existing experimental data on failing mouse ventricular myocytes and make experimentally testable predictions of a failing myocyte's behavior.
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Affiliation(s)
- Tesfaye Negash Asfaw
- Department of Mathematics and Statistics, Georgia State University, Atlanta, Georgia
| | - Vladimir E Bondarenko
- Department of Mathematics and Statistics, Georgia State University, Atlanta, Georgia.,Neuroscience Institute, Georgia State University, Atlanta, Georgia
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3
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Therapeutic Approaches of Ryanodine Receptor-Associated Heart Diseases. Int J Mol Sci 2022; 23:ijms23084435. [PMID: 35457253 PMCID: PMC9031589 DOI: 10.3390/ijms23084435] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 04/11/2022] [Accepted: 04/14/2022] [Indexed: 01/08/2023] Open
Abstract
Cardiac diseases are the leading causes of death, with a growing number of cases worldwide, posing a challenge for both healthcare and research. Therefore, the most relevant aim of cardiac research is to unravel the molecular pathomechanisms and identify new therapeutic targets. Cardiac ryanodine receptor (RyR2), the Ca2+ release channel of the sarcoplasmic reticulum, is believed to be a good therapeutic target in a group of certain heart diseases, collectively called cardiac ryanopathies. Ryanopathies are associated with the impaired function of the RyR, leading to heart diseases such as congestive heart failure (CHF), catecholaminergic polymorphic ventricular tachycardia (CPVT), arrhythmogenic right ventricular dysplasia type 2 (ARVD2), and calcium release deficiency syndrome (CRDS). The aim of the current review is to provide a short insight into the pathological mechanisms of ryanopathies and discuss the pharmacological approaches targeting RyR2.
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4
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Multisite phosphorylation of the cardiac ryanodine receptor: a random or coordinated event? Pflugers Arch 2020; 472:1793-1807. [PMID: 33078311 DOI: 10.1007/s00424-020-02473-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/03/2020] [Accepted: 10/02/2020] [Indexed: 10/23/2022]
Abstract
Many proteins are phosphorylated at more than one phosphorylation site to achieve precise tuning of protein function and/or integrate a multitude of signals into the activity of one protein. Increasing the number of phosphorylation sites significantly broadens the complexity of molecular mechanisms involved in processing multiple phosphorylation sites by one or more distinct kinases. The cardiac ryanodine receptor (RYR2) is a well-established multiple phospho-target of kinases activated in response to β-adrenergic stimulation because this Ca2+ channel is a critical component of Ca2+ handling machinery which is responsible for β-adrenergic enhancement of cardiac contractility. Our review presents a selective overview of the extensive, often conflicting, literature which focuses on identifying reliable lines of evidence to establish if multiple RYR2 phosphorylation is achieved randomly or in a specific sequence, and whether phosphorylation at individual sites is functionally specific and additive or similar and can therefore be substituted.
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5
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Campbell H, Aguilar-Sanchez Y, Quick AP, Dobrev D, Wehrens XHT. SPEG: a key regulator of cardiac calcium homeostasis. Cardiovasc Res 2020; 117:2175-2185. [PMID: 33067609 DOI: 10.1093/cvr/cvaa290] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/15/2020] [Accepted: 10/02/2020] [Indexed: 12/27/2022] Open
Abstract
Proper cardiac Ca2+ homeostasis is essential for normal excitation-contraction coupling. Perturbations in cardiac Ca2+ handling through altered kinase activity has been implicated in altered cardiac contractility and arrhythmogenesis. Thus, a better understanding of cardiac Ca2+ handling regulation is vital for a better understanding of various human disease processes. 'Striated muscle preferentially expressed protein kinase' (SPEG) is a member of the myosin light chain kinase family that is key for normal cardiac function. Work within the last 5 years has revealed that SPEG has a crucial role in maintaining normal cardiac Ca2+ handling through maintenance of transverse tubule formation and phosphorylation of junctional membrane complex proteins. Additionally, SPEG has been causally impacted in human genetic diseases such as centronuclear myopathy and dilated cardiomyopathy as well as in common acquired cardiovascular disease such as heart failure and atrial fibrillation. Given the rapidly emerging role of SPEG as a key cardiac Ca2+ regulator, we here present this review in order to summarize recent findings regarding the mechanisms of SPEG regulation of cardiac excitation-contraction coupling in both physiology and human disease. A better understanding of the roles of SPEG will be important for a more complete comprehension of cardiac Ca2+ regulation in physiology and disease.
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Affiliation(s)
- Hannah Campbell
- Cardiovascular Research Institute, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA.,Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.,Medical Scientist Training Program, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yuriana Aguilar-Sanchez
- Cardiovascular Research Institute, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA.,Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ann P Quick
- Cardiovascular Research Institute, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA.,Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Dobromir Dobrev
- Cardiovascular Research Institute, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA.,Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.,Institute of Pharmacology, University Duisburg-Essen, Essen, Germany
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA.,Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.,Center for Space Medicine, Baylor College of Medicine, Houston, TX 77030, USA
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6
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Pitoulis FG, Terracciano CM. Heart Plasticity in Response to Pressure- and Volume-Overload: A Review of Findings in Compensated and Decompensated Phenotypes. Front Physiol 2020; 11:92. [PMID: 32116796 PMCID: PMC7031419 DOI: 10.3389/fphys.2020.00092] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 01/27/2020] [Indexed: 12/20/2022] Open
Abstract
The adult human heart has an exceptional ability to alter its phenotype to adapt to changes in environmental demand. This response involves metabolic, mechanical, electrical, and structural alterations, and is known as cardiac plasticity. Understanding the drivers of cardiac plasticity is essential for development of therapeutic agents. This is particularly important in contemporary cardiology, which uses treatments with peripheral effects (e.g., on kidneys, adrenal glands). This review focuses on the effects of different hemodynamic loads on myocardial phenotype. We examine mechanical scenarios of pressure- and volume overload, from the initial insult, to compensated, and ultimately decompensated stage. We discuss how different hemodynamic conditions occur and are underlined by distinct phenotypic and molecular changes. We complete the review by exploring how current basic cardiac research should leverage available cardiac models to study mechanical load in its different presentations.
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7
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Sarcoplasmic reticulum and calcium signaling in muscle cells: Homeostasis and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 350:197-264. [PMID: 32138900 DOI: 10.1016/bs.ircmb.2019.12.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The sarco/endoplasmic reticulum is an extensive, dynamic and heterogeneous membranous network that fulfills multiple homeostatic functions. Among them, it compartmentalizes, stores and releases calcium within the intracellular space. In the case of muscle cells, calcium released from the sarco/endoplasmic reticulum in the vicinity of the contractile machinery induces cell contraction. Furthermore, sarco/endoplasmic reticulum-derived calcium also regulates gene transcription in the nucleus, energy metabolism in mitochondria and cytosolic signaling pathways. These diverse and overlapping processes require a highly complex fine-tuning that the sarco/endoplasmic reticulum provides by means of its numerous tubules and cisternae, specialized domains and contacts with other organelles. The sarco/endoplasmic reticulum also possesses a rich calcium-handling machinery, functionally coupled to both contraction-inducing stimuli and the contractile apparatus. Such is the importance of the sarco/endoplasmic reticulum for muscle cell physiology, that alterations in its structure, function or its calcium-handling machinery are intimately associated with the development of cardiometabolic diseases. Cardiac hypertrophy, insulin resistance and arterial hypertension are age-related pathologies with a common mechanism at the muscle cell level: the accumulation of damaged proteins at the sarco/endoplasmic reticulum induces a stress response condition termed endoplasmic reticulum stress, which impairs proper organelle function, ultimately leading to pathogenesis.
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Mohamed BA, Hartmann N, Tirilomis P, Sekeres K, Li W, Neef S, Richter C, Zeisberg EM, Kattner L, Didié M, Guan K, Schmitto JD, Lehnart SE, Luther S, Voigt N, Seidler T, Sossalla S, Hasenfuss G, Toischer K. Sarcoplasmic reticulum calcium leak contributes to arrhythmia but not to heart failure progression. Sci Transl Med 2018; 10:10/458/eaan0724. [DOI: 10.1126/scitranslmed.aan0724] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 01/30/2018] [Accepted: 08/09/2018] [Indexed: 12/30/2022]
Abstract
Increased sarcoplasmic reticulum (SR) Ca2+ leak via the cardiac ryanodine receptor (RyR2) has been suggested to play a mechanistic role in the development of heart failure (HF) and cardiac arrhythmia. Mice treated with a selective RyR2 stabilizer, rycal S36, showed normalization of SR Ca2+ leak and improved survival in pressure overload (PO) and myocardial infarction (MI) models. The development of HF, measured by echocardiography and molecular markers, showed no difference in rycal S36– versus placebo-treated mice. Reduction of SR Ca2+ leak in the PO model by the rycal-unrelated RyR2 stabilizer dantrolene did not mitigate HF progression. Development of HF was not aggravated by increased SR Ca2+ leak due to RyR2 mutation (R2474S) in volume overload, an SR Ca2+ leak–independent HF model. Arrhythmia episodes were reduced by rycal S36 treatment in PO and MI mice in vivo and ex vivo in Langendorff-perfused hearts. Isolated cardiomyocytes from murine failing hearts and human ventricular failing and atrial nonfailing myocardium showed reductions in delayed afterdepolarizations, in spontaneous and induced Ca2+ waves, and in triggered activity in rycal S36 versus placebo cells, whereas the Ca2+ transient, SR Ca2+ load, SR Ca2+ adenosine triphosphatase function, and action potential duration were not affected. Rycal S36 treatment of human induced pluripotent stem cells isolated from a patient with catecholaminergic polymorphic ventricular tachycardia could rescue the leaky RyR2 receptor. These results suggest that SR Ca2+ leak does not primarily influence contractile HF progression, whereas rycal S36 treatment markedly reduces ventricular arrhythmias, thereby improving survival in mice.
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Affiliation(s)
- Belal A. Mohamed
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Department of Medical Biochemistry and Molecular Biology, Faculty of Medicine, Mansoura University, Mansoura City 35516, Egypt
| | - Nico Hartmann
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
| | - Petros Tirilomis
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
| | - Karolina Sekeres
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Wener Li
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Stefan Neef
- Department of Internal Medicine II, University Hospital Regensburg, 93053 Regensburg, Germany
| | - Claudia Richter
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Research Group Biomedical Physics, Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
| | - Elisabeth M. Zeisberg
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
| | - Lars Kattner
- Endotherm Life Science Molecules, 66123 Saarbrücken, Germany
| | - Michael Didié
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Georg-August-University, 37075 Göttingen, Germany
| | - Kaomei Guan
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Technische Universität Dresden, 01307 Dresden, Germany
| | - Jan D. Schmitto
- Department of Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, 30625 Hannover, Germany
| | - Stephan E. Lehnart
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- BioMET, Center for Biomedical Engineering and Technology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Stefan Luther
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Research Group Biomedical Physics, Max Planck Institute for Dynamics and Self-Organization, 37077 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Georg-August-University, 37075 Göttingen, Germany
| | - Niels Voigt
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Institute of Pharmacology and Toxicology, Georg-August-University, 37075 Göttingen, Germany
| | - Tim Seidler
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
| | - Samuel Sossalla
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
- Department of Internal Medicine II, University Hospital Regensburg, 93053 Regensburg, Germany
| | - Gerd Hasenfuss
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
| | - Karl Toischer
- Department of Cardiology and Pneumology, Georg-August-University, 37075 Göttingen, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Göttingen, 37075 Göttingen, Germany
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Eblimit Z, Thevananther S, Karpen SJ, Taegtmeyer H, Moore DD, Adorini L, Penny DJ, Desai MS. TGR5 activation induces cytoprotective changes in the heart and improves myocardial adaptability to physiologic, inotropic, and pressure-induced stress in mice. Cardiovasc Ther 2018; 36:e12462. [PMID: 30070769 DOI: 10.1111/1755-5922.12462] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/12/2018] [Accepted: 07/30/2018] [Indexed: 12/13/2022] Open
Abstract
INTRODUCTION Administration of cholic acid, or its synthetic derivative, 6-alpha-ethyl-23(S)-methylcholic acid (INT-777), activates the membrane GPCR, TGR5, influences whole body metabolism, reduces atherosclerosis, and benefits the cardiovascular physiology in mice. Direct effects of TGR5 agonists, and the role for TGR5, on myocardial cell biology and stress response are unknown. METHODS Mice were fed chow supplemented with 0.5% cholic acid (CA) or 0.025% INT-777, a specific TGR5 agonist, or regular chow for 3 weeks. Anthropometric, biochemical, physiologic (electrocardiography and echocardiography), and molecular analysis was performed at baseline. CA and INT-777 fed mice were challenged with acute exercise-induced stress, acute catecholamine-induced stress, and hemodynamic stress induced by transverse aortic constriction (TAC) for a period of 8 weeks. In separate experiments, mice born with constitutive deletion of TGR5 in cardiomyocytes (CM-TGR5del ) were exposed to exercise, inotropic, and TAC-induced stress. RESULTS Administration of CA and INT-777 supplemented diets upregulated TGR5 expression and activated Akt, PKA, and ERK1/2 in the heart. CA and INT-777 fed mice showed improved exercise tolerance, improved sensitivity to catecholamine and attenuation in pathologic remodeling of the heart under hemodynamic stress. In contrast, CM-TGR5del showed poor response to exercise and catecholamine challenge as well as higher mortality and signs of accelerated cardiomyopathy under hemodynamic stress. CONCLUSIONS Bile acids, specifically TGR5 agonists, induce cytoprotective changes in the heart and improve myocardial response to physiologic, inotropic, and hemodynamic stress in mice. TGR5 plays a critical role in myocardial adaptability, and TGR5 activation may represent a potentially attractive treatment option in heart failure.
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Affiliation(s)
- Zeena Eblimit
- Section of Pediatric Critical Care, Baylor College of Medicine, Houston, Texas
| | | | - Saul J Karpen
- Pediatric Gastroenterology, Emory School of Medicine, Atlanta, Georgia
| | - Heinrich Taegtmeyer
- Department of Internal Medicine, Division of Cardiology, McGovern Medical School, University of Texas Health Science Center, Houston, Texas
| | - David D Moore
- Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas
| | | | - Daniel J Penny
- Department of Pediatric Cardiology, Baylor College of Medicine, Houston, Texas
| | - Moreshwar S Desai
- Section of Pediatric Critical Care, Baylor College of Medicine, Houston, Texas
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Li N, Zhou T, Geng X, Jin Y, Wang X, Liu S, Xu X, Gao D, Li Q, Liu Z. Identification of novel genes significantly affecting growth in catfish through GWAS analysis. Mol Genet Genomics 2017; 293:587-599. [PMID: 29230585 DOI: 10.1007/s00438-017-1406-1] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 12/07/2017] [Indexed: 12/01/2022]
Abstract
Growth is the most important economic trait in aquaculture. Improvements in growth-related traits can enhance production, reduce costs and time to produce market-size fish. Catfish is the major aquaculture species in the United States, accounting for 65% of the US finfish production. However, the genes underlying growth traits in catfish were not well studied. Currently, the majority of the US catfish industry uses hybrid catfish derived from channel catfish female mated with blue catfish male. Interestingly, channel catfish and blue catfish exhibit differences in growth-related traits, and therefore the backcross progenies provide an efficient system for QTL analysis. In this study, we conducted a genome-wide association study for catfish body weight using the 250 K SNP array with 556 backcross progenies generated from backcross of male F1 hybrid (female channel catfish × male blue catfish) with female channel catfish. A genomic region of approximately 1 Mb on linkage group 5 was found to be significantly associated with body weight. In addition, four suggestively associated QTL regions were identified on linkage groups 1, 2, 23 and 24. Most candidate genes in the associated regions are known to be involved in muscle growth and bone development, some of which were reported to be associated with obesity in humans and pigs, suggesting that the functions of these genes may be evolutionarily conserved in controlling growth. Additional fine mapping or functional studies should allow identification of the causal genes for fast growth in catfish, and elucidation of molecular mechanisms of regulation of growth in fish.
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Affiliation(s)
- Ning Li
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Tao Zhou
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Xin Geng
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Yulin Jin
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Xiaozhu Wang
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Shikai Liu
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Xiaoyan Xu
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA.,Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Shanghai, 201306, China
| | - Dongya Gao
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Qi Li
- The Shellfish Genetics and Breeding Laboratory, Fisheries College, Ocean University of China, Qingdao, 266003, Shandong, China
| | - Zhanjiang Liu
- Department of Biology, Syracuse University, Syracuse, NY, 13244, USA.
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11
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Hershberger KA, Abraham DM, Martin AS, Mao L, Liu J, Gu H, Locasale JW, Hirschey MD. Sirtuin 5 is required for mouse survival in response to cardiac pressure overload. J Biol Chem 2017; 292:19767-19781. [PMID: 28972174 PMCID: PMC5712617 DOI: 10.1074/jbc.m117.809897] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/16/2017] [Indexed: 01/05/2023] Open
Abstract
In mitochondria, the sirtuin SIRT5 is an NAD+-dependent protein deacylase that controls several metabolic pathways. Although a wide range of SIRT5 targets have been identified, the overall function of SIRT5 in organismal metabolic homeostasis remains unclear. Given that SIRT5 expression is highest in the heart and that sirtuins are commonly stress-response proteins, we used an established model of pressure overload-induced heart muscle hypertrophy caused by transverse aortic constriction (TAC) to determine SIRT5's role in cardiac stress responses. Remarkably, SIRT5KO mice had reduced survival upon TAC compared with wild-type mice but exhibited no mortality when undergoing a sham control operation. The increased mortality with TAC was associated with increased pathological hypertrophy and with key abnormalities in both cardiac performance and ventricular compliance. By combining high-resolution MS-based metabolomic and proteomic analyses of cardiac tissues from wild-type and SIRT5KO mice, we found several biochemical abnormalities exacerbated in the SIRT5KO mice, including apparent decreases in fatty acid oxidation and glucose oxidation as well as an overall decrease in mitochondrial NAD+/NADH. Together, these abnormalities suggest that SIRT5 deacylates protein substrates involved in cellular oxidative metabolism to maintain mitochondrial energy production. Overall, the functional and metabolic results presented here suggest an accelerated development of cardiac dysfunction in SIRT5KO mice in response to TAC, explaining increased mortality upon cardiac stress. Our findings reveal a key role for SIRT5 in maintaining cardiac oxidative metabolism under pressure overload to ensure survival.
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Affiliation(s)
- Kathleen A Hershberger
- From the Duke Molecular Physiology Institute and Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina 27701
- the Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710
| | - Dennis M Abraham
- the Department of Medicine, Division of Cardiology and Duke Cardiovascular Physiology Core, Duke University Medical Center, Durham, North Carolina 27710
| | - Angelical S Martin
- From the Duke Molecular Physiology Institute and Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina 27701
- the Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710
| | - Lan Mao
- the Department of Medicine, Division of Cardiology and Duke Cardiovascular Physiology Core, Duke University Medical Center, Durham, North Carolina 27710
| | - Juan Liu
- From the Duke Molecular Physiology Institute and Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina 27701
- the Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710
| | - Hongbo Gu
- Cell Signaling Technology Inc., Danvers, Massachusetts 01923, and
| | - Jason W Locasale
- From the Duke Molecular Physiology Institute and Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina 27701
- the Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710
| | - Matthew D Hirschey
- From the Duke Molecular Physiology Institute and Sarah W. Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina 27701,
- the Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710
- the Division of Endocrinology, Metabolism, and Nutrition, Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710
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12
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Ding Z, Yuan J, Liang Y, Wu J, Gong H, Ye Y, Jiang G, Yin P, Li Y, Zhang G, Yang C, Guo J, Chen Z, Wang X, Weng L, Zou Y. Ryanodine Receptor Type 2 Plays a Role in the Development of Cardiac Fibrosis under Mechanical Stretch Through TGFβ-1. Int Heart J 2017; 58:957-961. [PMID: 29162778 DOI: 10.1536/ihj.16-572] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Ryanodine receptor type 2 (RyR-2), the main Ca2+ release channel from sarcoplasmic reticulum in cardiomyocytes, plays a vital role in the regulation ofmyocardial contractile function and cardiac hypertrophy. However, the role of RyR-2 in cardiac fibrosis during the development of cardiac hypertrophy remains unclear.In this study, we examined whether RyR-2 regulates TGFβ1, which is secreted from cardiomyocytes and exerts on cardiac fibrosis using cultured cardiomyocytes and cardiac fibroblasts of neonatal rats. The expression of RyR-2 was found only in cardiomyocytesbut not in cardiac fibroblasts. Mechanical stretch induced upregulation of TGFβ1 in cardiomyocytes and RyR-2 knockdown significantly suppressed the upregulation of TGFβ1 expression. The transcript levels of collagen genes were also decreased in fibroblasts compare with wild type, although the expression of both two kinds was higher than those in stationary cardiomyocytes (non-stretch). With the inhibition of the TGFβ1-neutralizing antibody, the expression of collagen genes has no significant difference between the mechanically stretched cardiomyocytes and non-stretchedones. These results indicate that RyR-2 regulated TGFβ1 expression in mechanically stretched cardiomyocytes and TGFβ1 promoted collagen formation of cardiac fibroblasts by a paracrine mechanism.RyR-2 in mechanical stretch could promote the development of cardiac fibrosis involving TGFβ1-dependent paracrine mechanism. Our findings provided more insight into comprehensively understanding the molecular role of RyR-2 in regulating cardiac fibrosis.
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Affiliation(s)
- Zhiwen Ding
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Jie Yuan
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Yanyan Liang
- Department of Cardiology, The First People's Hospital, Shanghai Jiao Tong University School of Medicine
| | - Jian Wu
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Hui Gong
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Yong Ye
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Guoliang Jiang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Peipei Yin
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Yang Li
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Guoping Zhang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Chunjie Yang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Junjie Guo
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University.,Department of Cardiology, The Affiliated Hospital of Qingdao University
| | - Zhidan Chen
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Xingxu Wang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Liqing Weng
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
| | - Yunzeng Zou
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital and Institute of Biomedical Sciences, Fudan University
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13
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Loss of MD1 exacerbates pressure overload-induced left ventricular structural and electrical remodelling. Sci Rep 2017; 7:5116. [PMID: 28698617 PMCID: PMC5505950 DOI: 10.1038/s41598-017-05379-w] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 05/30/2017] [Indexed: 12/24/2022] Open
Abstract
Myeloid differentiation protein 1 (MD1) has been implicated in numerous pathophysiological processes, including immune regulation, obesity, insulin resistance, and inflammation. However, the role of MD1 in cardiac remodelling remains incompletely understood. We used MD1-knockout (KO) mice and their wild-type littermates to determine the functional significance of MD1 in the regulation of aortic banding (AB)-induced left ventricular (LV) structural and electrical remodelling and its underlying mechanisms. After 4 weeks of AB, MD1-KO hearts showed substantial aggravation of LV hypertrophy, fibrosis, LV dilation and dysfunction, and electrical remodelling, which resulted in overt heart failure and increased electrophysiological instability. Moreover, MD1-KO-AB cardiomyocytes showed increased diastolic sarcoplasmic reticulum (SR) Ca2+ leak, reduced Ca2+ transient amplitude and SR Ca2+ content, decreased SR Ca2+-ATPase2 expression, and increased phospholamban and Na+/Ca2+-exchanger 1 protein expression. Mechanistically, the adverse effects of MD1 deletion on LV remodelling were related to hyperactivated CaMKII signalling and increased impairment of intracellular Ca2+ homeostasis, whereas the increased electrophysiological instability was partly attributed to exaggerated prolongation of cardiac repolarisation, decreased action potential duration alternans threshold, and increased diastolic SR Ca2+ leak. Therefore, our study on MD1 could provide new therapeutic strategies for preventing/treating heart failure.
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14
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Quick AP, Landstrom AP, Wang Q, Beavers DL, Reynolds JO, Barreto-Torres G, Tran V, Showell J, Philippen LE, Morris SA, Skapura D, Bos JM, Pedersen SE, Pautler RG, Ackerman MJ, Wehrens XHT. Novel junctophilin-2 mutation A405S is associated with basal septal hypertrophy and diastolic dysfunction. ACTA ACUST UNITED AC 2017; 2:56-67. [PMID: 28393127 PMCID: PMC5384575 DOI: 10.1016/j.jacbts.2016.11.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
A JPH2 A405S mutation was found in a human HCM patient. A novel echocardiographic imaging plane revealed septal hypertrophy in a mouse model bearing the human JPH2 mutation, thereby causally linking it to HCM pathogenesis. This alpha helical JPH2 mutation resulted in decreased transverse tubule regularity and aberrant calcium handling in septal cardiomyocytes.
Junctophilin-2 (JPH2) is a structural calcium (Ca2+) handling protein, which approximates the cardiomyocyte transverse tubules (TTs) to the sarcoplasmic reticulum. This facilitates communication of the voltage-gated Ca2+ channel and the ryanodine receptor RyR2. A human patient with hypertrophic cardiomyopathy was positive for a JPH2 mutation substituting alanine-405—located within the alpha helix domain—with a serine (A405S). Using a novel mouse echocardiography plane, we found that mice bearing this JPH2 mutation developed increased subvalvular septal thickness. Cardiomyocytes from the septa of these mice displayed irregular TTs and abnormal Ca2+ handling including increased SERCA activity.
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Affiliation(s)
- Ann P Quick
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Andrew P Landstrom
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics (Cardiology), Baylor College of Medicine, Houston, TX, USA
| | - Qiongling Wang
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - David L Beavers
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Julia O Reynolds
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Giselle Barreto-Torres
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Viet Tran
- Department of Medicine (Cardiology), Baylor College of Medicine, Houston, TX, USA
| | - Jordan Showell
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Leonne E Philippen
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - Shaine A Morris
- Department of Pediatrics (Cardiology), Baylor College of Medicine, Houston, TX, USA
| | - Darlene Skapura
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA
| | - J Martijn Bos
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - Steen E Pedersen
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Robia G Pautler
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Michael J Ackerman
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota, USA
| | - Xander H T Wehrens
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA; Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA; Department of Medicine (Cardiology), Baylor College of Medicine, Houston, TX, USA
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15
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Ji Y, Guo X, Zhang Z, Huang Z, Zhu J, Chen QH, Gui L. CaMKIIδ meditates phenylephrine induced cardiomyocyte hypertrophy through store-operated Ca 2+ entry. Cardiovasc Pathol 2016; 27:9-17. [PMID: 27940402 DOI: 10.1016/j.carpath.2016.11.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 11/10/2016] [Accepted: 11/18/2016] [Indexed: 01/01/2023] Open
Abstract
Evidence suggests that store-operated Ca2+ entry (SOCE) is involved in the hypertrophy of cardiomyocytes. The signaling mechanisms of SOCE contributing to cardiac hypertrophy following phenylephrine (PE) stimulation are not fully understood. Ca2+/calmodulin-dependent protein kinase II δ (CaMKIIδ) plays an important role in regulating intracellular Ca2+ hemostasis and function in the cardimyocytes. This study is aimed to determine the role of CaMKIIδ in regulating the PE-induced myocardial hypertrophy and the associated molecular signaling mechanisms. We used primary cultures of neonatal cardimyocytes isolated from the left ventricle of Sprague Dawley rats to investigate the effects of CaMKIIδ on myocardial hypertrophy and intracellular Ca2+ mobilization. We found that the expression of CaMKIIδ was enhanced in PE-induced hypertrophic cardiomyocytes. CaMKIIδ siRNA, CaMKII inhibitor KN93, and SOCE blocker BTP2 attenuated the increase in the expression of CaMKIIδ and normalized the hypertrophic markers, atrial natriuretic peptide and brain natriuretic peptide, and size of cardiomyocytes induced by PE stimulation. The protein level of stromal interaction molecule 1 and Orai1, the essential components of the SOCE, is also enhanced in hypertrophic cardiomyocytes, which were normalized by CaMKIIδ siRNA and KN93 treatment. Hypertrophic cardiomyocytes showed an increase in the peak of Ca2+ transient following store depletion, which was inhibited by SOCE blocker BTP2, CaMKIIδ siRNA, and KN93. The Ca2+ currents through Ca2+ release-activated Ca2+ channels were increased in PE-treated cardiomyocytes and were attenuated by CaMKIIδ siRNA and KN93. These data indicate that PE-induced myocardial hypertrophy requires a complex signaling pathway that involves activation of both CaMKIIδ and SOCE. In conclusion, these studies reveal that up-regulation of CaMKIIδ may contribute to the PE-induced myocardial hypertrophy through the activation of SOCE expressed in the cardiomyocytes.
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Affiliation(s)
- Yawei Ji
- Department of Cardiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, PR China
| | - Xin Guo
- Department of Urology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, PR China
| | - Zhe Zhang
- Department of Cardiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, PR China
| | - Zhuyun Huang
- Department of Cardiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, PR China
| | - Jianghua Zhu
- Department of Cardiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, PR China
| | - Qing-Hui Chen
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, MI 49931, USA
| | - Le Gui
- Department of Cardiology, Affiliated Hospital of Nantong University, Nantong, Jiangsu 226001, PR China.
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16
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Pang J, Wang J, Zhang Y, Xu F, Chen Y. Targeting acetaldehyde dehydrogenase 2 (ALDH2) in heart failure-Recent insights and perspectives. Biochim Biophys Acta Mol Basis Dis 2016; 1863:1933-1941. [PMID: 27742538 DOI: 10.1016/j.bbadis.2016.10.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 09/24/2016] [Accepted: 10/06/2016] [Indexed: 12/20/2022]
Abstract
Heart failure is one of the major causes of the ever-rising mortality globally. ALDH2 rs671 polymorphism is proven to be closely related to the prevalence of CAD, hypertension, diabetes mellitus and alcoholism, which are etiological factors of heart failure. In addition, growing evidence supports a possible role for ALDH2 in different forms of heart failure. In this mini-review, we will review the recent insights regarding the effects of ALDH2 polymorphism on etiological factors of heart failure and underlying mechanisms involved. In addition, we will also discuss the booming epigenetic information in this field which will greatly improve our understanding of the cardiovascular effect of ALDH2. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure edited by Dr. Jun Ren & Yingmei Zhang.
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Affiliation(s)
- Jiaojiao Pang
- Department of Emergency, Qilu Hospital, Shandong University, Jinan, China; Chest Pain Center, Qilu Hospital, Shandong University, Jinan, China; Institute of Emergency and Critical Care Medicine, Shandong University, Jinan, China; Key Laboratory of Emergency and Critical Care Medicine of Shandong Province, Qilu Hospital, Shandong University, Jinan, China; Key Laboratory of Cardiovascular Remodeling & Function Research, Chinese Ministry of Education & Chinese Ministry of Public Health, Qilu Hospital, Shandong University, Jinan, China.
| | - Jiali Wang
- Department of Emergency, Qilu Hospital, Shandong University, Jinan, China; Chest Pain Center, Qilu Hospital, Shandong University, Jinan, China; Institute of Emergency and Critical Care Medicine, Shandong University, Jinan, China; Key Laboratory of Emergency and Critical Care Medicine of Shandong Province, Qilu Hospital, Shandong University, Jinan, China; Key Laboratory of Cardiovascular Remodeling & Function Research, Chinese Ministry of Education & Chinese Ministry of Public Health, Qilu Hospital, Shandong University, Jinan, China.
| | - Yingmei Zhang
- Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital, Fudan University, Shanghai, China; Center for Cardiovascular Research and Alternative Medicine, University of Wyoming College of Health Sciences, Laramie, WY, USA
| | - Feng Xu
- Department of Emergency, Qilu Hospital, Shandong University, Jinan, China; Chest Pain Center, Qilu Hospital, Shandong University, Jinan, China; Institute of Emergency and Critical Care Medicine, Shandong University, Jinan, China; Key Laboratory of Emergency and Critical Care Medicine of Shandong Province, Qilu Hospital, Shandong University, Jinan, China; Key Laboratory of Cardiovascular Remodeling & Function Research, Chinese Ministry of Education & Chinese Ministry of Public Health, Qilu Hospital, Shandong University, Jinan, China.
| | - Yuguo Chen
- Department of Emergency, Qilu Hospital, Shandong University, Jinan, China; Chest Pain Center, Qilu Hospital, Shandong University, Jinan, China; Institute of Emergency and Critical Care Medicine, Shandong University, Jinan, China; Key Laboratory of Emergency and Critical Care Medicine of Shandong Province, Qilu Hospital, Shandong University, Jinan, China; Key Laboratory of Cardiovascular Remodeling & Function Research, Chinese Ministry of Education & Chinese Ministry of Public Health, Qilu Hospital, Shandong University, Jinan, China.
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17
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Reynolds JO, Quick AP, Wang Q, Beavers DL, Philippen LE, Showell J, Barreto-Torres G, Thuerauf DJ, Doroudgar S, Glembotski CC, Wehrens XHT. Junctophilin-2 gene therapy rescues heart failure by normalizing RyR2-mediated Ca 2+ release. Int J Cardiol 2016; 225:371-380. [PMID: 27760414 DOI: 10.1016/j.ijcard.2016.10.021] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 10/05/2016] [Accepted: 10/07/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND Junctophilin-2 (JPH2) is the primary structural protein for the coupling of transverse (T)-tubule associated cardiac L-type Ca channels and type-2 ryanodine receptors on the sarcoplasmic reticulum within junctional membrane complexes (JMCs) in cardiomyocytes. Effective signaling between these channels ensures adequate Ca-induced Ca release required for normal cardiac contractility. Disruption of JMC subcellular domains, a common feature of failing hearts, has been attributed to JPH2 downregulation. Here, we tested the hypothesis that adeno-associated virus type 9 (AAV9) mediated overexpression of JPH2 could halt the development of heart failure in a mouse model of transverse aortic constriction (TAC). METHODS AND RESULTS Following TAC, a progressive decrease in ejection fraction was paralleled by a progressive decrease of cardiac JPH2 levels. AAV9-mediated expression of JPH2 rescued cardiac contractility in mice subjected to TAC. AAV9-JPH2 also preserved T-tubule structure. Moreover, the Ca2+ spark frequency was reduced and the Ca2+ transient amplitude was increased in AAV9-JPH2 mice following TAC, consistent with JPH2-mediated normalization of SR Ca2+ handling. CONCLUSIONS This study demonstrates that AAV9-mediated JPH2 gene therapy maintained cardiac function in mice with early stage heart failure. Moreover, restoration of JPH2 levels prevented loss of T-tubules and suppressed abnormal SR Ca2+ leak associated with contractile failure following TAC. These findings suggest that targeting JPH2 might be an attractive therapeutic approach for treating pathological cardiac remodeling during heart failure.
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Affiliation(s)
- Julia O Reynolds
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ann P Quick
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Qiongling Wang
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - David L Beavers
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Translational Biology and Molecular Medicine Program, Baylor College of Medicine, Houston, TX 77030, USA
| | - Leonne E Philippen
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jordan Showell
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Giselle Barreto-Torres
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Donna J Thuerauf
- San Diego State University Heart Institute and Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Shirin Doroudgar
- Department of Cardiology, Angiology, and Pneumology, University Hospital Heidelberg, Innere Medizin III, Im Neuenheimer Feld 669, 69120, Heidelberg, Germany; DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, 69120, Heidelberg, Germany
| | - Christopher C Glembotski
- San Diego State University Heart Institute and Department of Biology, San Diego State University, San Diego, CA 92182, USA
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Medicine/Cardiology, Baylor College of Medicine, Houston, TX 77030, USA; Dept. of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
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18
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Bonsu KO, Owusu IK, Buabeng KO, Reidpath DD, Kadirvelu A. Review of novel therapeutic targets for improving heart failure treatment based on experimental and clinical studies. Ther Clin Risk Manag 2016; 12:887-906. [PMID: 27350750 PMCID: PMC4902145 DOI: 10.2147/tcrm.s106065] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Heart failure (HF) is a major public health priority due to its epidemiological transition and the world's aging population. HF is typified by continuous loss of contractile function with reduced, normal, or preserved ejection fraction, elevated vascular resistance, fluid and autonomic imbalance, and ventricular dilatation. Despite considerable advances in the treatment of HF over the past few decades, mortality remains substantial. Pharmacological treatments including β-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone antagonists have been proven to prolong the survival of patients with HF. However, there are still instances where patients remain symptomatic, despite optimal use of existing therapeutic agents. This understanding that patients with chronic HF progress into advanced stages despite receiving optimal treatment has increased the quest for alternatives, exploring the roles of additional pathways that contribute to the development and progression of HF. Several pharmacological targets associated with pathogenesis of HF have been identified and novel therapies have emerged. In this work, we review recent evidence from proposed mechanisms to the outcomes of experimental and clinical studies of the novel pharmacological agents that have emerged for the treatment of HF.
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Affiliation(s)
- Kwadwo Osei Bonsu
- School of Medicine and Health Sciences, Monash University Sunway Campus, Jalan Lagoon Selatan, Bandar Sunway, Subang Jaya, Selangor, Malaysia
- Accident and Emergency Directorate, Komfo Anokye Teaching Hospital, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Isaac Kofi Owusu
- Department of Medicine, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Kwame Ohene Buabeng
- Department of Clinical and Social Pharmacy, College of Health Sciences, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Daniel Diamond Reidpath
- School of Medicine and Health Sciences, Monash University Sunway Campus, Jalan Lagoon Selatan, Bandar Sunway, Subang Jaya, Selangor, Malaysia
| | - Amudha Kadirvelu
- School of Medicine and Health Sciences, Monash University Sunway Campus, Jalan Lagoon Selatan, Bandar Sunway, Subang Jaya, Selangor, Malaysia
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19
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RyR2 QQ2958 Genotype and Risk of Malignant Ventricular Arrhythmias. Cardiol Res Pract 2016; 2016:2868604. [PMID: 26904356 PMCID: PMC4745938 DOI: 10.1155/2016/2868604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 01/05/2016] [Indexed: 11/21/2022] Open
Abstract
Ventricular arrhythmias are one of the most common causes of death in developed countries. The use of implantable cardiac defibrillators is the most effective treatment to prevent sudden cardiac death. To date, the ejection fraction is the only approved clinical variable used to determine suitability for defibrillator placement in subjects with heart failure. The purpose of this study was to assess whether genetic polymorphisms found in the ryanodine receptor type 2 (Q2958R) and histidine-rich calcium-binding protein (S96A) might serve as markers for arrhythmias. Genotyping was performed in 235 patients treated with defibrillator for primary and secondary prevention of arrhythmias. No significant association was found between the S96A polymorphism and arrhythmia onset, whereas the QQ2958 genotype in the ryanodine receptor gene was correlated with an increased risk of life-threatening arrhythmias. Concurrent stressor conditions, such as hypertension, seem to increase this effect. Our findings might help to better identify patients who could benefit from defibrillator implantation.
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20
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Ferrantini C, Coppini R, Scellini B, Ferrara C, Pioner JM, Mazzoni L, Priori S, Cerbai E, Tesi C, Poggesi C. R4496C RyR2 mutation impairs atrial and ventricular contractility. ACTA ACUST UNITED AC 2015; 147:39-52. [PMID: 26666913 PMCID: PMC4692489 DOI: 10.1085/jgp.201511450] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 11/09/2015] [Indexed: 12/11/2022]
Abstract
A ryanodine receptor 2 mutation associated with catecholaminergic polymorphic ventricular tachycardia renders cardiomyocytes incapable of mediating a positive inotropic response. Ryanodine receptor (RyR2) is the major Ca2+ channel of the cardiac sarcoplasmic reticulum (SR) and plays a crucial role in the generation of myocardial force. Changes in RyR2 gating properties and resulting increases in its open probability (Po) are associated with Ca2+ leakage from the SR and arrhythmias; however, the effects of RyR2 dysfunction on myocardial contractility are unknown. Here, we investigated the possibility that a RyR2 mutation associated with catecholaminergic polymorphic ventricular tachycardia, R4496C, affects the contractile function of atrial and ventricular myocardium. We measured isometric twitch tension in left ventricular and atrial trabeculae from wild-type mice and heterozygous transgenic mice carrying the R4496C RyR2 mutation and found that twitch force was comparable under baseline conditions (30°C, 2 mM [Ca2+]o, 1 Hz). However, the positive inotropic responses to high stimulation frequency, 0.1 µM isoproterenol, and 5 mM [Ca2+]o were decreased in R4496C trabeculae, as was post-rest potentiation. We investigated the mechanisms underlying inotropic insufficiency in R4496C muscles in single ventricular myocytes. Under baseline conditions, the amplitude of the Ca2+ transient was normal, despite the reduced SR Ca2+ content. Under inotropic challenge, however, R4496C myocytes were unable to boost the amplitude of Ca2+ transients because they are incapable of properly increasing the amount of Ca2+ stored in the SR because of a larger SR Ca2+ leakage. Recovery of force in response to premature stimuli was faster in R4496C myocardium, despite the unchanged rates of recovery of L-type Ca2+ channel current (ICa-L) and SR Ca2+ content in single myocytes. A faster recovery from inactivation of the mutant R4496C channels could explain this behavior. In conclusion, changes in RyR2 channel gating associated with the R4496C mutation could be directly responsible for the alterations in both ventricular and atrial contractility. The increased RyR2 Po and fractional Ca2+ release from the SR induced by the R4496C mutation preserves baseline contractility despite a slight decrease in SR Ca2+ content, but cannot compensate for the inability to increase SR Ca2+ content during inotropic challenge.
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Affiliation(s)
- Cecilia Ferrantini
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Raffaele Coppini
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Beatrice Scellini
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Claudia Ferrara
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Josè Manuel Pioner
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Luca Mazzoni
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Silvia Priori
- IRCCS Fondazione Salvatore Maugeri, 27100 Pavia, Italy
| | - Elisabetta Cerbai
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Chiara Tesi
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
| | - Corrado Poggesi
- Center for Molecular Medicine and Applied Biophysics, University of Florence, 50121 Florence, Italy
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21
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Roe AT, Frisk M, Louch WE. Targeting cardiomyocyte Ca2+ homeostasis in heart failure. Curr Pharm Des 2015; 21:431-48. [PMID: 25483944 PMCID: PMC4475738 DOI: 10.2174/138161282104141204124129] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2014] [Accepted: 08/06/2014] [Indexed: 12/19/2022]
Abstract
Improved treatments for heart failure patients will require the development of novel therapeutic strategies that target basal disease
mechanisms. Disrupted cardiomyocyte Ca2+ homeostasis is recognized as a major contributor to the heart failure phenotype, as it
plays a key role in systolic and diastolic dysfunction, arrhythmogenesis, and hypertrophy and apoptosis signaling. In this review, we outline
existing knowledge of the involvement of Ca2+ homeostasis in these deficits, and identify four promising targets for therapeutic intervention:
the sarcoplasmic reticulum Ca2+ ATPase, the Na+-Ca2+ exchanger, the ryanodine receptor, and t-tubule structure. We discuss
experimental data indicating the applicability of these targets that has led to recent and ongoing clinical trials, and suggest future therapeutic
approaches.
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Affiliation(s)
| | | | - William E Louch
- Institute for Experimental Medical Research, Kirkeveien 166, 4.etg. Bygg 7, Oslo University Hospital Ullevål, 0407 Oslo, Norway.
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Wang Y, Li ZC, Zhang P, Poon E, Kong CW, Boheler KR, Huang Y, Li RA, Yao X. Nitric Oxide-cGMP-PKG Pathway Acts on Orai1 to Inhibit the Hypertrophy of Human Embryonic Stem Cell-Derived Cardiomyocytes. Stem Cells 2015; 33:2973-84. [PMID: 26269433 DOI: 10.1002/stem.2118] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 07/15/2015] [Indexed: 11/08/2022]
Abstract
Cardiac hypertrophy is an abnormal enlargement of heart muscle. It frequently results in congestive heart failure, which is a leading cause of human death. Previous studies demonstrated that the nitric oxide (NO), cyclic GMP (cGMP), and protein kinase G (PKG) signaling pathway can inhibit cardiac hypertrophy and thus improve cardiac function. However, the underlying mechanisms are not fully understood. Here, based on the human embryonic stem cell-derived cardiomyocyte (hESC-CM) model system, we showed that Orai1, the pore-forming subunit of store-operated Ca(2+) entry (SOCE), is the downstream effector of PKG. Treatment of hESC-CMs with an α-adrenoceptor agonist phenylephrine (PE) caused a marked hypertrophy, which was accompanied by an upregulation of Orai1. Moreover, suppression of Orai1 expression/activity using Orai1-siRNAs or a dominant-negative construct Orai1(G98A) inhibited the hypertrophy, suggesting that Orai1-mediated SOCE is indispensable for the PE-induced hypertrophy of hESC-CMs. In addition, the hypertrophy was inhibited by NO and cGMP via activating PKG. Importantly, substitution of Ala for Ser(34) in Orai1 abolished the antihypertrophic effects of NO, cGMP, and PKG. Furthermore, PKG could directly phosphorylate Orai1 at Ser(34) and thus prevent Orai1-mediated SOCE. Together, we conclude that NO, cGMP, and PKG inhibit the hypertrophy of hESC-CMs via PKG-mediated phosphorylation on Orai1-Ser-34. These results provide novel mechanistic insights into the action of cGMP-PKG-related antihypertrophic agents, such as NO donors and sildenafil.
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Affiliation(s)
- Y Wang
- Li Ka Shing Institute of Health Sciences and School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, People's Republic of China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People's Republic of China.,Department of Hematology, The 3rd Xiangya Hospital, Central South University, Changsha, People's Republic of China
| | - Z C Li
- Li Ka Shing Institute of Health Sciences and School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, People's Republic of China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People's Republic of China
| | - P Zhang
- Li Ka Shing Institute of Health Sciences and School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, People's Republic of China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People's Republic of China
| | - E Poon
- Stem Cell and Regenerative Medicine Consortium, The University of Hong Kong, Hong Kong, People's Republic of China.,The Department of Physiology, The University of Hong Kong, Hong Kong, People's Republic of China
| | - C W Kong
- Stem Cell and Regenerative Medicine Consortium, The University of Hong Kong, Hong Kong, People's Republic of China
| | - K R Boheler
- Stem Cell and Regenerative Medicine Consortium, The University of Hong Kong, Hong Kong, People's Republic of China.,The Department of Physiology, The University of Hong Kong, Hong Kong, People's Republic of China
| | - Y Huang
- Li Ka Shing Institute of Health Sciences and School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, People's Republic of China
| | - R A Li
- Stem Cell and Regenerative Medicine Consortium, The University of Hong Kong, Hong Kong, People's Republic of China
| | - X Yao
- Li Ka Shing Institute of Health Sciences and School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Hong Kong, People's Republic of China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, People's Republic of China
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23
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Kwong JQ, Lu X, Correll RN, Schwanekamp JA, Vagnozzi RJ, Sargent MA, York AJ, Zhang J, Bers DM, Molkentin JD. The Mitochondrial Calcium Uniporter Selectively Matches Metabolic Output to Acute Contractile Stress in the Heart. Cell Rep 2015; 12:15-22. [PMID: 26119742 DOI: 10.1016/j.celrep.2015.06.002] [Citation(s) in RCA: 254] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 04/15/2015] [Accepted: 05/30/2015] [Indexed: 11/16/2022] Open
Abstract
In the heart, augmented Ca(2+) fluxing drives contractility and ATP generation through mitochondrial Ca(2+) loading. Pathologic mitochondrial Ca(2+) overload with ischemic injury triggers mitochondrial permeability transition pore (MPTP) opening and cardiomyocyte death. Mitochondrial Ca(2+) uptake is primarily mediated by the mitochondrial Ca(2+) uniporter (MCU). Here, we generated mice with adult and cardiomyocyte-specific deletion of Mcu, which produced mitochondria refractory to acute Ca(2+) uptake, with impaired ATP production, and inhibited MPTP opening upon acute Ca(2+) challenge. Mice lacking Mcu in the adult heart were also protected from acute ischemia-reperfusion injury. However, resting/basal mitochondrial Ca(2+) levels were normal in hearts of Mcu-deleted mice, and mitochondria lacking MCU eventually loaded with Ca(2+) after stress stimulation. Indeed, Mcu-deleted mice were unable to immediately sprint on a treadmill unless warmed up for 30 min. Hence, MCU is a dedicated regulator of short-term mitochondrial Ca(2+) loading underlying a "fight-or-flight" response that acutely matches cardiac workload with ATP production.
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Affiliation(s)
- Jennifer Q Kwong
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Xiyuan Lu
- Department of Pharmacology, University of California-Davis, Davis, CA 95616, USA
| | - Robert N Correll
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Jennifer A Schwanekamp
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Ronald J Vagnozzi
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Michelle A Sargent
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Allen J York
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA
| | - Jianyi Zhang
- Department of Medicine, Leilihei Heart Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - Donald M Bers
- Department of Pharmacology, University of California-Davis, Davis, CA 95616, USA
| | - Jeffery D Molkentin
- Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH 45229, USA; Howard Hughes Medical Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
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24
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25
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Wang W, Landstrom AP, Wang Q, Munro ML, Beavers D, Ackerman MJ, Soeller C, Wehrens XHT. Reduced junctional Na+/Ca2+-exchanger activity contributes to sarcoplasmic reticulum Ca2+ leak in junctophilin-2-deficient mice. Am J Physiol Heart Circ Physiol 2014; 307:H1317-26. [PMID: 25193470 DOI: 10.1152/ajpheart.00413.2014] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Expression silencing of junctophilin-2 (JPH2) in mouse heart leads to ryanodine receptor type 2 (RyR2)-mediated sarcoplasmic reticulum (SR) Ca(2+) leak and rapid development of heart failure. The mechanism and physiological significance of JPH2 in regulating RyR2-mediated SR Ca(2+) leak remains elusive. We sought to elucidate the role of JPH2 in regulating RyR2-mediated SR Ca(2+) release in the setting of cardiac failure. Cardiac myocytes isolated from tamoxifen-inducible conditional knockdown mice of JPH2 (MCM-shJPH2) were subjected to confocal Ca(2+) imaging. MCM-shJPH2 cardiomyocytes exhibited an increased spark frequency width with altered spark morphology, which caused increased SR Ca(2+) leakage. Single channel studies identified an increased RyR2 open probability in MCM-shJPH2 mice. The increase in spark frequency and width was observed only in MCM-shJPH2 and not found in mice with increased RyR2 open probability with native JPH2 expression. Na(+)/Ca(2+)-exchanger (NCX) activity was reduced by 50% in MCM-shJPH2 with no detectable change in NCX expression. Additionally, 50% inhibition of NCX through Cd(2+) administration alone was sufficient to increase spark width in myocytes obtained from wild-type mice. Additionally, superresolution analysis of RyR2 and NCX colocalization showed a reduced overlap between RyR2 and NCX in MCM-shJPH2 mice. In conclusion, decreased JPH2 expression causes increased SR Ca(2+) leakage by directly increasing open probability of RyR2 and by indirectly reducing junctional NCX activity through increased dyadic cleft Ca(2+). This demonstrates two novel and independent cellular mechanisms by which JPH2 regulates RyR2-mediated SR Ca(2+) leak and heart failure development.
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Affiliation(s)
- Wei Wang
- Department of Molecular Physiology and Biophysics, Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
| | - Andrew P Landstrom
- Department of Pediatrics, Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
| | - Qiongling Wang
- Department of Molecular Physiology and Biophysics, Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
| | - Michelle L Munro
- Department of Physics, University of Exeter and Department of Physiology, University of Auckland, Auckland, New Zealand; and
| | - David Beavers
- Department of Molecular Physiology and Biophysics, Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas
| | - Michael J Ackerman
- Windland Smith Rice Sudden Death Genomics Laboratory, Departments of Medicine, Pediatrics, and Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota
| | - Christian Soeller
- Department of Physics, University of Exeter and Department of Physiology, University of Auckland, Auckland, New Zealand; and
| | - Xander H T Wehrens
- Department of Molecular Physiology and Biophysics, Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas; Department of Medicine/Cardiology, Cardiovascular Research Institute, Baylor College of Medicine, Houston, Texas;
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26
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A knock-in mouse model of N-terminal R420W mutation of cardiac ryanodine receptor exhibits arrhythmogenesis with abnormal calcium dynamics in cardiomyocytes. Biochem Biophys Res Commun 2014; 452:665-8. [DOI: 10.1016/j.bbrc.2014.08.132] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 08/25/2014] [Indexed: 11/22/2022]
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27
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Beavers DL, Landstrom AP, Chiang DY, Wehrens XHT. Emerging roles of junctophilin-2 in the heart and implications for cardiac diseases. Cardiovasc Res 2014; 103:198-205. [PMID: 24935431 DOI: 10.1093/cvr/cvu151] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Cardiomyocytes rely on a highly specialized subcellular architecture to maintain normal cardiac function. In a little over a decade, junctophilin-2 (JPH2) has become recognized as a cardiac structural protein critical in forming junctional membrane complexes (JMCs), which are subcellular domains essential for excitation-contraction coupling within the heart. While initial studies described the structure of JPH2 and its role in anchoring junctional sarcoplasmic reticulum and transverse-tubule (T-tubule) membrane invaginations, recent research has an expanded role of JPH2 in JMC structure and function. For example, JPH2 is necessary for the development of postnatal T-tubule in mammals. It is also critical for the maintenance of the complex JMC architecture and stabilization of local ion channels in mature cardiomyocytes. Loss of this function by mutations or down-regulation of protein expression has been linked to hypertrophic cardiomyopathy, arrhythmias, and progression of disease in failing hearts. In this review, we summarize current views on the roles of JPH2 within the heart and how JPH2 dysregulation may contribute to a variety of cardiac diseases.
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Affiliation(s)
- David L Beavers
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA Translational Biology and Molecular Medicine Program, Baylor College of Medicine, Houston, TX, USA
| | - Andrew P Landstrom
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - David Y Chiang
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA Translational Biology and Molecular Medicine Program, Baylor College of Medicine, Houston, TX, USA
| | - Xander H T Wehrens
- Cardiovascular Research Institute, Baylor College of Medicine, Houston, TX, USA Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, USA Deptartment of Medicine (Cardiology), Baylor College of Medicine, Houston, TX, USA
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28
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Tagashira H, Bhuiyan MS, Shioda N, Fukunaga K. Fluvoxamine rescues mitochondrial Ca2+ transport and ATP production through σ(1)-receptor in hypertrophic cardiomyocytes. Life Sci 2013; 95:89-100. [PMID: 24373833 DOI: 10.1016/j.lfs.2013.12.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Revised: 11/19/2013] [Accepted: 12/12/2013] [Indexed: 01/15/2023]
Abstract
AIMS We previously reported that fluvoxamine, a selective serotonin reuptake inhibitor with high affinity for the σ1-receptor (σ1R), ameliorates cardiac hypertrophy and dysfunction via σ1R stimulation. Although σ1R on non-cardiomyocytes interacts with the IP3 receptor (IP3R) to promote mitochondrial Ca(2+) transport, little is known about its physiological and pathological relevance in cardiomyocytes. MAIN METHODS Here we performed Ca(2+) imaging and measured ATP production to define the role of σ1Rs in regulating sarcoplasmic reticulum (SR)-mitochondrial Ca(2+) transport in neonatal rat ventricular cardiomyocytes treated with angiotensin II to promote hypertrophy. KEY FINDING These cardiomyocytes exhibited imbalances in expression levels of σ1R and IP3R and impairments in both phenylephrine-induced mitochondrial Ca(2+) mobilization from the SR and ATP production. Interestingly, σ1R stimulation with fluvoxamine rescued impaired mitochondrial Ca(2+) mobilization and ATP production, an effect abolished by treatment of cells with the σ1R antagonist, NE-100. Under physiological conditions, fluvoxamine stimulation of σ1Rs suppressed intracellular Ca(2+) mobilization through IP3Rs and ryanodine receptors (RyRs). In vivo, chronic administration of fluvoxamine to TAC mice also rescued impaired ATP production. SIGNIFICANCE These results suggest that σ1R stimulation with fluvoxamine promotes SR-mitochondrial Ca(2+) transport and mitochondrial ATP production, whereas σ1R stimulation suppresses intracellular Ca(2+) overload through IP3Rs and RyRs. These mechanisms likely underlie in part the anti-hypertrophic and cardioprotective action of the σ1R agonists including fluvoxamine.
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Affiliation(s)
- Hideaki Tagashira
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Md Shenuarin Bhuiyan
- Division of Molecular Cardiovascular Biology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Norifumi Shioda
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Kohji Fukunaga
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan.
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29
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Sedej S, Schmidt A, Denegri M, Walther S, Matovina M, Arnstein G, Gutschi EM, Windhager I, Ljubojević S, Negri S, Heinzel FR, Bisping E, Vos MA, Napolitano C, Priori SG, Kockskämper J, Pieske B. Subclinical abnormalities in sarcoplasmic reticulum Ca(2+) release promote eccentric myocardial remodeling and pump failure death in response to pressure overload. J Am Coll Cardiol 2013; 63:1569-79. [PMID: 24315909 DOI: 10.1016/j.jacc.2013.11.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 10/31/2013] [Accepted: 11/01/2013] [Indexed: 12/26/2022]
Abstract
OBJECTIVES This study sought to explore whether subclinical alterations of sarcoplasmic reticulum (SR) Ca(2+) release through cardiac ryanodine receptors (RyR2) aggravate cardiac remodeling in mice carrying a human RyR2(R4496C+/-) gain-of-function mutation in response to pressure overload. BACKGROUND RyR2 dysfunction causes increased diastolic SR Ca(2+) release associated with arrhythmias and contractile dysfunction in inherited and acquired cardiac diseases, such as catecholaminergic polymorphic ventricular tachycardia and heart failure (HF). METHODS Functional and structural properties of wild-type and catecholaminergic polymorphic ventricular tachycardia-associated RyR2(R4496C+/-) hearts were characterized under conditions of pressure overload induced by transverse aortic constriction (TAC). RESULTS Wild-type and RyR2(R4496C+/-) hearts had comparable structural and functional properties at baseline. After TAC, RyR2(R4496C+/-) hearts responded with eccentric hypertrophy, substantial fibrosis, ventricular dilation, and reduced fractional shortening, ultimately resulting in overt HF. RyR2(R4496C+/-)-TAC cardiomyocytes showed increased incidence of spontaneous SR Ca(2+) release events, reduced Ca(2+) transient peak amplitude, and SR Ca(2+) content as well as reduced SR Ca(2+)-ATPase 2a and increased Na(+)/Ca(2+)-exchanger protein expression. HF phenotype in RyR2(R4496C+/-)-TAC mice was associated with increased mortality due to pump failure but not tachyarrhythmic events. RyR2-stabilizer K201 markedly reduced Ca(2+) spark frequency in RyR2(R4496C+/-)-TAC cardiomyocytes. Mini-osmotic pump infusion of K201 prevented deleterious remodeling and improved survival in RyR2(R4496C+/-)-TAC mice. CONCLUSIONS The combination of subclinical congenital alteration of SR Ca(2+) release and pressure overload promoted eccentric remodeling and HF death in RyR2(R4496C+/-) mice, and pharmacological RyR2 stabilization prevented this deleterious interaction. These findings suggest potential clinical relevance for patients with acquired or inherited gain-of-function of RyR2-mediated SR Ca(2+) release.
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Affiliation(s)
- Simon Sedej
- Department of Cardiology, Medical University of Graz, Graz, Austria; Ludwig Boltzmann Institute for Translational Heart Failure Research, Graz, Austria.
| | - Albrecht Schmidt
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Marco Denegri
- IRCCS Salvatore Maugeri Foundation and Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Stefanie Walther
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Marinko Matovina
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Georg Arnstein
- Department of Cardiology, Medical University of Graz, Graz, Austria
| | - Eva-Maria Gutschi
- Department of Cardiology, Medical University of Graz, Graz, Austria; Ludwig Boltzmann Institute for Translational Heart Failure Research, Graz, Austria
| | | | - Senka Ljubojević
- Department of Cardiology, Medical University of Graz, Graz, Austria; Ludwig Boltzmann Institute for Translational Heart Failure Research, Graz, Austria
| | - Sara Negri
- IRCCS Salvatore Maugeri Foundation and Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Frank R Heinzel
- Department of Cardiology, Medical University of Graz, Graz, Austria; Ludwig Boltzmann Institute for Translational Heart Failure Research, Graz, Austria
| | - Egbert Bisping
- Department of Cardiology, Medical University of Graz, Graz, Austria; Ludwig Boltzmann Institute for Translational Heart Failure Research, Graz, Austria
| | - Marc A Vos
- Department of Medical Physiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Carlo Napolitano
- IRCCS Salvatore Maugeri Foundation and Department of Molecular Medicine, University of Pavia, Pavia, Italy; Leon H. Charney Division of Cardiology, New York University School of Medicine, New York, New York
| | - Silvia G Priori
- IRCCS Salvatore Maugeri Foundation and Department of Molecular Medicine, University of Pavia, Pavia, Italy; Leon H. Charney Division of Cardiology, New York University School of Medicine, New York, New York
| | - Jens Kockskämper
- Institute of Pharmacology and Clinical Pharmacy, Philipps-University of Marburg, Marburg, Germany
| | - Burkert Pieske
- Department of Cardiology, Medical University of Graz, Graz, Austria; Ludwig Boltzmann Institute for Translational Heart Failure Research, Graz, Austria.
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30
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Tagashira H, Bhuiyan MS, Fukunaga K. Diverse regulation of IP3 and ryanodine receptors by pentazocine through σ1-receptor in cardiomyocytes. Am J Physiol Heart Circ Physiol 2013; 305:H1201-12. [PMID: 23934856 DOI: 10.1152/ajpheart.00300.2013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although pentazocine binds to σ1-receptor (σ1R) with high affinity, the physiological relevance of its binding remains unclear. We first confirmed that σ1R stimulation with pentazocine rescues contractile dysfunction following pressure overload (PO)-induced cardiac hypertrophy ovariectomized (OVX) female rats. In in vivo studies, vehicle, pentazocine (0.5-1.0 mg/kg ip), and NE-100 (1.0 mg/kg po), a σ1R antagonist, were administered for 4 wk (once daily) starting from the onset of aortic banding after OVX. We also examined antihypertrophic effects of pentazocine (0.5-1 μM) in cultured cardiomyocytes exposed to angiotensin II. Pentazocine administration significantly inhibited PO-induced cardiac hypertrophy and rescued hypertrophy-induced impairment of cardiac dysfunctions such as left ventricular end-diastolic pressure, left ventricular developed pressure, and left ventricular contraction and relaxation (±dp/dt) rates. Coadministration of NE-100 with pentazocine eliminated pentazocine-induced amelioration of heart dysfunction. Interestingly, pentazocine administration inhibited PO-induced σ1R reduction and inositol-1,4,5-trisphosphate (IP3) receptor type 2 (IP3R2) upregulation in heart. Therefore, the reduced mitochondrial ATP production following PO was restored by pentazocine administration. Furthermore, we found that σ1R binds to the ryanodine receptor (RyR) in addition to IP3 receptor (IP3R) in cardiomyocytes. The σ1R/RyR complexes were decreased following OVX-PO and restored by pentazocine administration. We noticed that pentazocine inhibits the ryanodine-induced Ca(2+) release from sarcoplasmic reticulum (SR) in cultured cardiomyocytes. Taken together, the stimulation of σ1R by pentazocine rescues cardiac dysfunction by restoring IP3R-mediated mitochondrial ATP production and by suppressing RyR-mediated Ca(2+) leak from SR in cardiomyocytes.
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MESH Headings
- Adenosine Triphosphate/biosynthesis
- Angiotensin II/pharmacology
- Animals
- Anisoles/pharmacology
- Calcium/metabolism
- Cardiomegaly/metabolism
- Cardiomegaly/physiopathology
- Cells, Cultured
- Female
- Heart/drug effects
- Hypertrophy, Left Ventricular/metabolism
- Hypertrophy, Left Ventricular/physiopathology
- Inositol 1,4,5-Trisphosphate Receptors/drug effects
- Inositol 1,4,5-Trisphosphate Receptors/metabolism
- Mitochondria/drug effects
- Mitochondria/metabolism
- Myocardial Contraction/drug effects
- Myocytes, Cardiac/drug effects
- Myocytes, Cardiac/metabolism
- Narcotic Antagonists/pharmacology
- Narcotics/pharmacology
- Ovariectomy
- Pentazocine/pharmacology
- Propylamines/pharmacology
- Rats
- Rats, Wistar
- Receptors, sigma/agonists
- Receptors, sigma/antagonists & inhibitors
- Ryanodine Receptor Calcium Release Channel/drug effects
- Ryanodine Receptor Calcium Release Channel/metabolism
- Sarcoplasmic Reticulum/drug effects
- Sarcoplasmic Reticulum/metabolism
- Vasoconstrictor Agents/pharmacology
- Sigma-1 Receptor
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Affiliation(s)
- Hideaki Tagashira
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
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Wu SP, Cheng CM, Lanz RB, Wang T, Respress JL, Ather S, Chen W, Tsai SJ, Wehrens XHT, Tsai MJ, Tsai SY. Atrial identity is determined by a COUP-TFII regulatory network. Dev Cell 2013; 25:417-26. [PMID: 23725765 DOI: 10.1016/j.devcel.2013.04.017] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 04/11/2013] [Accepted: 04/29/2013] [Indexed: 11/29/2022]
Abstract
Atria and ventricles exhibit distinct molecular profiles that produce structural and functional differences between the two cardiac compartments. However, the factors that determine these differences remain largely undefined. Cardiomyocyte-specific COUP-TFII ablation produces ventricularized atria that exhibit ventricle-like action potentials, increased cardiomyocyte size, and development of extensive T tubules. Changes in atrial characteristics are accompanied by alterations of 2,584 genes, of which 81% were differentially expressed between atria and ventricles, suggesting that a major function of myocardial COUP-TFII is to determine atrial identity. Chromatin immunoprecipitation assays using E13.5 atria identified classic atrial-ventricular identity genes Tbx5, Hey2, Irx4, MLC2v, MLC2a, and MLC1a, among many other cardiac genes, as potential COUP-TFII direct targets. Collectively, our results reveal that COUP-TFII confers atrial identity through direct binding and by modulating expression of a broad spectrum of genes that have an impact on atrial development and function.
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Affiliation(s)
- San-pin Wu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
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32
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Crossland RF, Durgan DJ, Lloyd EE, Phillips SC, Reddy AK, Marrelli SP, Bryan RM. A new rodent model for obstructive sleep apnea: effects on ATP-mediated dilations in cerebral arteries. Am J Physiol Regul Integr Comp Physiol 2013; 305:R334-42. [PMID: 23761641 DOI: 10.1152/ajpregu.00244.2013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Obstructive sleep apnea (OSA), a condition in which the upper airway collapses during sleep, is strongly associated with metabolic and cardiovascular diseases. Little is known how OSA affects the cerebral circulation. The goals of this study were 1) to develop a rat model of chronic OSA that involved apnea and 2) to test the hypothesis that 4 wk of apneas during the sleep cycle alters endothelium-mediated dilations in middle cerebral arteries (MCAs). An obstruction device, which was chronically implanted into the trachea of rats, inflated to obstruct the airway 30 times/h for 8 h during the sleep cycle. After 4 wk of apneas, MCAs were isolated, pressurized, and exposed to luminally applied ATP, an endothelial P2Y2 receptor agonist that dilates through endothelial-derived nitric oxide (NO) and endothelial-dependent hyperpolarization (EDH). Dilations to ATP were attenuated ~30% in MCAs from rats undergoing apneas compared with those from a sham control group (P < 0.04 group effect; n = 7 and 10, respectively). When the NO component of the dilation was blocked to isolate the EDH component, the response to ATP in MCAs from the sham and apnea groups was similar. This finding suggests that the attenuated dilation to ATP must occur through reduced NO. In summary, we have successfully developed a novel rat model for chronic OSA that incorporates apnea during the sleep cycle. Using this model, we demonstrate that endothelial dysfunction occurred by 4 wk of apnea, likely increasing the vulnerability of the brain to cerebrovascular related accidents.
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Affiliation(s)
- Randy F Crossland
- Department of Anesthesiology, Baylor College of Medicine, Houston, Texas
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Fauconnier J, Roberge S, Saint N, Lacampagne A. Type 2 ryanodine receptor: A novel therapeutic target in myocardial ischemia/reperfusion. Pharmacol Ther 2013; 138:323-32. [DOI: 10.1016/j.pharmthera.2013.01.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 01/22/2013] [Indexed: 10/27/2022]
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Marx SO, Marks AR. Dysfunctional ryanodine receptors in the heart: new insights into complex cardiovascular diseases. J Mol Cell Cardiol 2013; 58:225-31. [PMID: 23507255 DOI: 10.1016/j.yjmcc.2013.03.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 02/26/2013] [Accepted: 03/02/2013] [Indexed: 01/07/2023]
Abstract
Calcium dependent signaling is highly regulated in cardiomyocytes and determines the force of cardiac muscle contraction. The cardiac ryanodine receptors (RyR2) play important roles in health and disease. Modulation of RyR2 by phosphorylation is required for sympathetic regulation of cardiac function. Abnormal regulation of RyR2 contributes to heart failure, and atrial and ventricular arrhythmias. RyR2 channels are oxidized, nitrosylated, and hyperphosphorylated by protein kinase A (PKA) in heart failure, resulting in "leaky" channels. These leaky RyR2 channels contribute to depletion of calcium from the sarcoplasmic reticulum, resulting in defective cardiac excitation-contraction coupling. In this review, we discuss both the importance of PKA and calcium/calmodulin-dependent kinase II (CaMKII) regulation of RyR2 in health, and how altered phosphorylation, nitrosylation and oxidation of RyR2 channels lead to cardiac disease. Correcting these defects using either genetic manipulation (knock-in) in mice, or specific and novel small molecules ameliorates the RyR2 dysfunction, reducing the progression to heart failure and the incidence of arrhythmias.
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Affiliation(s)
- Steven O Marx
- Division of Cardiology, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
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Belevych AE, Radwański PB, Carnes CA, Györke S. 'Ryanopathy': causes and manifestations of RyR2 dysfunction in heart failure. Cardiovasc Res 2013; 98:240-7. [PMID: 23408344 DOI: 10.1093/cvr/cvt024] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The cardiac ryanodine receptor (RyR2), a Ca(2+) release channel on the membrane of the sarcoplasmic reticulum (SR), plays a key role in determining the strength of the heartbeat by supplying Ca(2+) required for contractile activation. Abnormal RyR2 function is recognized as an important part of the pathophysiology of heart failure (HF). While in the normal heart, the balance between the cytosolic and intra-SR Ca(2+) regulation of RyR2 function maintains the contraction-relaxation cycle, in HF, this behaviour is compromised by excessive post-translational modifications of the RyR2. Such modification of the Ca(2+) release channel impairs the ability of the RyR2 to properly deactivate leading to a spectrum of Ca(2+)-dependent pathologies that include cardiac systolic and diastolic dysfunction, arrhythmias, and structural remodelling. In this article, we present an overview of recent advances in our understanding of the underlying causes and pathological consequences of abnormal RyR2 function in the failing heart. We also discuss the implications of these findings for HF therapy.
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Affiliation(s)
- Andriy E Belevych
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
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Kalyanasundaram A, Lacombe VA, Belevych AE, Brunello L, Carnes CA, Janssen PML, Knollmann BC, Periasamy M, Gyørke S. Up-regulation of sarcoplasmic reticulum Ca(2+) uptake leads to cardiac hypertrophy, contractile dysfunction and early mortality in mice deficient in CASQ2. Cardiovasc Res 2012; 98:297-306. [PMID: 23135969 DOI: 10.1093/cvr/cvs334] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
AIMS Although aberrant Ca(2+) release (i.e. Ca(2+) 'leak') from the sarcoplasmic reticulum (SR) through cardiac ryanodine receptors (RyR2) is linked to heart failure (HF), it remains unknown whether and under what conditions SR-derived Ca(2+) can actually cause HF. We tested the hypothesis that combining dysregulated RyR2 function with facilitated Ca(2+) uptake into SR will exacerbate abnormal SR Ca(2+) release and induce HF. We also examined the mechanisms for these alterations. METHODS AND RESULTS We crossbred mice deficient in expression of cardiac calsequestrin (CASQ2) with mice overexpressing the skeletal muscle isoform of SR Ca(2+)ATPase (SERCA1a). The new double-mutant strains displayed early mortality, congestive HF with left ventricular dilated hypertrophy, and decreased ejection fraction. Intact right ventricular muscle preparations from double-mutant mice preserved normal systolic contractile force but were susceptible to spontaneous contractions. Double-mutant cardiomyocytes while preserving normal amplitude of systolic Ca(2+) transients displayed marked disturbances in diastolic Ca(2+) handling in the form of multiple, periodic Ca(2+) waves and wavelets. Dysregulated myocyte Ca(2+) handling and structural and functional cardiac pathology in double-mutant mice were associated with increased rate of apoptotic cell death. Qualitatively similar results were obtained in a hybrid strain created by crossing CASQ2 knockout mice with mice deficient in phospholamban. CONCLUSION We demonstrate that enhanced SR Ca(2+) uptake combined with dysregulated RyR2s results in sustained diastolic Ca(2+) release causing apoptosis, dilated cardiomyopathy, and early mortality. Our data also suggest that up-regulation of SERCA activity must be advocated with caution as a therapy for HF in the context of abnormal RyR2 function.
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Affiliation(s)
- Anuradha Kalyanasundaram
- Department of Physiology and Cell Biology, College of Medicine, 505 Davis Heart and Lung Research Institute, The Ohio State University, 473 W 12th Ave, Columbus, OH 43210, USA
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37
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Ryanodine receptor phosphorylation, calcium/calmodulin-dependent protein kinase II, and life-threatening ventricular arrhythmias. Trends Cardiovasc Med 2012; 21:48-51. [PMID: 22578240 DOI: 10.1016/j.tcm.2012.02.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ryanodine receptor (RyR2) dysfunction, which may result from a variety of mechanisms, has been implicated in the pathogenesis of cardiac arrhythmias and heart failure. In this review, we discuss the important role of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) in the regulation of RyR2-mediated Ca(2+) release. In particular, we examine how pathological activation of CaMKII can lead to an increased risk of sudden arrhythmic death. Finally, we discuss how reduction of CaMKII-mediated RyR2 hyperactivity might reduce the risk of arrhythmias and may serve as a rationale for future pharmacotherapeutic approaches.
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Bround MJ, Asghari P, Wambolt RB, Bohunek L, Smits C, Philit M, Kieffer TJ, Lakatta EG, Boheler KR, Moore EDW, Allard MF, Johnson JD. Cardiac ryanodine receptors control heart rate and rhythmicity in adult mice. Cardiovasc Res 2012; 96:372-80. [PMID: 22869620 DOI: 10.1093/cvr/cvs260] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
AIMS The molecular mechanisms controlling heart function and rhythmicity are incompletely understood. While it is widely accepted that the type 2 ryanodine receptor (Ryr2) is the major Ca(2+) release channel in excitation-contraction coupling, the role of these channels in setting a consistent beating rate remains controversial. Gain-of-function RYR2 mutations in humans and genetically engineered mouse models are known to cause Ca(2+) leak, arrhythmias, and sudden cardiac death. Embryonic stem-cell derived cardiomyocytes lacking Ryr2 display slower beating rates, but no supporting in vivo evidence has been presented. The aim of the present study was to test the hypothesis that RYR2 loss-of-function would reduce heart rate and rhythmicity in vivo. METHODS AND RESULTS We generated inducible, tissue-specific Ryr2 knockout mice with acute ∼50% loss of RYR2 protein in the heart but not in other tissues. Echocardiography, working heart perfusion, and in vivo ECG telemetry demonstrated that deletion of Ryr2 was sufficient to cause bradycardia and arrhythmia. Our results also show that cardiac Ryr2 knockout mice exhibit functional and structural hallmarks of heart failure, including sudden cardiac death. CONCLUSION These results illustrate that the RYR2 channel plays an essential role in pacing heart rate. Moreover, we find that RYR2 loss-of-function can lead to fatal arrhythmias typically associated with gain-of-function mutations. Given that RYR2 levels can be reduced in pathological conditions, including heart failure and diabetic cardiomyopathy, we predict that RYR2 loss contributes to disease-associated bradycardia, arrhythmia, and sudden death.
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Affiliation(s)
- Michael J Bround
- Cardiovascular Research Group, Life Sciences Institute, University of British Columbia, 5358 Life Sciences Building, 2350 Health Sciences Mall, Vancouver, BC, Canada V6T 1Z3
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Xu H, Zhang Y, Sun J, Wei J, Sun L, Zhang J. Effect of distinct sources of Ca2+ on cardiac hypertrophy in cardiomyocytes. Exp Biol Med (Maywood) 2012; 237:271-8. [DOI: 10.1258/ebm.2011.011273] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
It is believed that intracellular calcium (Ca2+) overload can cause the cardiac hypertrophy, but it is possible that the Ca2+ entering the cytoplasm through distinct pathways will induce various effects on cardiomyocytes. The aim of the present study is to explore the effect of different sources of Ca2+ on cardiomyocyte hypertrophy. The cardiomyocytes isolated from neonatal Sprague–Dawley rats were treated with three agents (ionomycin, caffeine and angiotensin II [Ang II]) that increased the intracellular Ca2+ concentration via different pathways. Treatments with ionomycin, caffeine and Ang II for 24 h caused a significant increase in resting [Ca2+]i by 108.0 ± 7.8%, 102.0 ± 6.9% and 59.8 ± 3.3%, respectively. Caffeine and Ang II increased the cell surface area of cardiomyocytes and the mRNA level of atrial natriuretic peptide, brain natriuretic peptide and β-myosin heavy chain, but ionomycin did not. Moreover, sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) activity and the amplitudes of the twitch [Ca2+]i transients were reduced in the caffeine-treated group and Ang II-treated group. Furthermore, cardiomyocyte hypertrophy induced by caffeine was inhibited by cyclosporin A (CsA) and KN93, whereas cardiomyocyte hypertrophy induced by Ang II was inhibited by KN93, but not CsA. Our results show that cardiomyocyte hypertrophy is associated with SERCA2a activity, contractile performance and signaling pathways of CaMKII and/or calcineurin, whereas the Ca2+ overload is not sufficient to cause the cardiomyocyte hypertrophy.
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Affiliation(s)
- Hao Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Yali Zhang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Junqing Sun
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jinhong Wei
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Lijun Sun
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
| | - Jianbao Zhang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, China
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40
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Vinet L, Pezet M, Bito V, Briec F, Biesmans L, Rouet-Benzineb P, Gellen B, Prévilon M, Chimenti S, Vilaine JP, Charpentier F, Sipido KR, Mercadier JJ. Cardiac FKBP12.6 overexpression protects against triggered ventricular tachycardia in pressure overloaded mouse hearts. Basic Res Cardiol 2012; 107:246. [DOI: 10.1007/s00395-012-0246-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 12/23/2011] [Accepted: 01/19/2012] [Indexed: 10/14/2022]
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Ke J, Xiao X, Chen F, He L, Dai MS, Wang XP, Chen B, Chen M, Zhang CT. Function of the CaMKII-ryanodine receptor signaling pathway in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia. World J Emerg Med 2012; 3:65-70. [PMID: 25215041 DOI: 10.5847/wjem.j.issn.1920-8642.2012.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2011] [Accepted: 12/19/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Calcium calmodulin-dependent kinase II (CaMKII) can be more active in patients with left ventricular hypertrophy (LVH), which in turn causes phosphorylation of ryanodine receptors, resulting in inactivation and the instability of intracellular calcium homeostasis. The present study aimed to determine the effect of CaMKII-ryanodine receptor pathway signaling in rabbits with left ventricular hypertrophy and triggered ventricular arrhythmia. METHODS Forty New Zealand rabbits were randomized into four groups (10 per group): sham group, LVH group, KN-93 group (LVH+KN-93), and ryanodine group (LVH+ryanodine). Rabbits in the LVH, KN-93, and ryanodine groups were used to establish a left ventricular hypertrophy model by the coarctation of the abdominal aorta, while those in the sham group did not undergo the coarctation. After eight weeks, action potentials (APs) were recorded simultaneously in the endocardium and epicardium, and a transmural electrocardiogram (ECG) was also recorded in the rabbit left ventricular wedge model. Drugs were administered to the animals in the KN-93 and ryanodine groups, and the frequency of triggered APs and ventricular tachycardia was recorded after the rabbits were given isoprenaline (1 μmol/L) and high-frequency stimulation. RESULTS The frequency (animals/group) of triggered APs was 0/10 in the sham group, 10/10 in the LVH group, 4/10 in the KN-93 group, and 1/10 in the ryanodine group. The frequencies of ventricular tachycardia were 0/10, 9/10, 3/10, and 1/10, respectively. The frequencies of polymorphic ventricular tachycardia or ventricular fibrillation were 0/10, 7/10, 2/10, and 1/10, respectively. The frequencies of triggered ventricular arrhythmias in the KN-93 and ryanodine groups were much lower than those in the LVH group (P<0.05). CONCLUSIONS KN-93 and ryanodine can effectively reduce the occurrence of triggered ventricular arrhythmia in rabbits with LVH. The CaMKII-ryanodine signaling pathway can be used as a new means of treating ventricular arrhythmia.
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Affiliation(s)
- Jun Ke
- Department of Emergency Internal Medicine, Fujian Provincial Hospital, Provincial Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Xing Xiao
- Integrated Department, Tongji Hospital Affiliated to Tongji Medical College of Huazhong Science Technology University, Wuhan 430030, China
| | - Feng Chen
- Department of Emergency Internal Medicine, Fujian Provincial Hospital, Provincial Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Li He
- Department of Cardiology, Tongji Hospital Affiliated to Tongji Medical College of Huazhong Science Technology University, Wuhan 430030, China
| | - Mu-Sen Dai
- Department of Emergency Internal Medicine, Fujian Provincial Hospital, Provincial Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Xiao-Ping Wang
- Department of Emergency Internal Medicine, Fujian Provincial Hospital, Provincial Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Bing Chen
- Department of Emergency Internal Medicine, Fujian Provincial Hospital, Provincial Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Min Chen
- Department of Emergency Internal Medicine, Fujian Provincial Hospital, Provincial Clinical Medical College of Fujian Medical University, Fuzhou 350001, China
| | - Cun-Tai Zhang
- Integrated Department, Tongji Hospital Affiliated to Tongji Medical College of Huazhong Science Technology University, Wuhan 430030, China
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Zou Y, Liang Y, Gong H, Zhou N, Ma H, Guan A, Sun A, Wang P, Niu Y, Jiang H, Takano H, Toko H, Yao A, Takeshima H, Akazawa H, Shiojima I, Wang Y, Komuro I, Ge J. Ryanodine Receptor Type 2 Is Required for the Development of Pressure Overload-Induced Cardiac Hypertrophy. Hypertension 2011; 58:1099-110. [PMID: 21986507 DOI: 10.1161/hypertensionaha.111.173500] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ryanodine receptor type 2 (RyR-2) mediates Ca
2+
release from sarcoplasmic reticulum and contributes to myocardial contractile function. However, the role of RyR-2 in the development of cardiac hypertrophy is not completely understood. Here, mice with or without reduction of
RyR-2
gene (
RyR-2
+/−
and wild-type, respectively) were analyzed. At baseline, there was no difference in morphology of cardiomyocyte and heart and cardiac contractility between
RyR-2
+/−
and wild-type mice, although Ca
2+
release from sarcoplasmic reticulum was impaired in isolated
RyR-2
+/−
cardiomyocytes. During a 3-week period of pressure overload, which was induced by constriction of transverse aorta, isolated
RyR-2
+/−
cardiomyocytes displayed more reduction of Ca
2+
transient amplitude, rate of an increase in intracellular Ca
2+
concentration during systole, and percentile of fractional shortening, and hearts of
RyR-2
+/−
mice displayed less compensated hypertrophy, fibrosis, and contractility; more apoptosis with less autophagy of cardiomyocytes; and similar decrease of angiogenesis as compared with wild-type ones. Moreover, constriction of transverse aorta-induced increases in the activation of calcineurin, extracellular signal-regulated protein kinases, and protein kinase B/Akt but not that of Ca
2+
/calmodulin-dependent protein kinase II, and its downstream targets in the heart of wild-type mice were abolished in the
RyR-2
+/−
one, suggesting that RyR-2 is a regulator of calcineurin, extracellular signal-regulated protein kinases, and Akt but not of calmodulin-dependent protein kinase II activation during pressure overload. Taken together, our data indicate that RyR-2 contributes to the development of cardiac hypertrophy and adaptation of cardiac function during pressure overload through regulation of the sarcoplasmic reticulum Ca
2+
release; activation of calcineurin, extracellular signal-regulated protein kinases, and Akt; and cardiomyocyte survival.
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Affiliation(s)
- Yunzeng Zou
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Yanyan Liang
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Hui Gong
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Ning Zhou
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Hong Ma
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Aili Guan
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Aijun Sun
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Ping Wang
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Yuhong Niu
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Hong Jiang
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Hiroyuki Takano
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Haruhiro Toko
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Atsushi Yao
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Hiroshi Takeshima
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Hiroshi Akazawa
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Ichiro Shiojima
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Yuqi Wang
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Issei Komuro
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
| | - Junbo Ge
- From the Shanghai Institute of Cardiovascular Diseases, Zhongshan Hospital (Y.Z., Y.L., N.Z., A.G., A.S., Y.N., H.J., J.G.) and Institutes of Biomedical Sciences (H.G.), Fudan University, Shanghai, China; Department of Vascular Surgery (Y.W.), Zhongshan Hospital, Fudan University, Shanghai, China; Department of Cardiology (H.M.), Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China; Department of Cardiovascular Science and Medicine (P.W., H.Taka., H.To.), Chiba
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Goonasekera SA, Hammer K, Auger-Messier M, Bodi I, Chen X, Zhang H, Reiken S, Elrod JW, Correll RN, York AJ, Sargent MA, Hofmann F, Moosmang S, Marks AR, Houser SR, Bers DM, Molkentin JD. Decreased cardiac L-type Ca²⁺ channel activity induces hypertrophy and heart failure in mice. J Clin Invest 2011; 122:280-90. [PMID: 22133878 DOI: 10.1172/jci58227] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Accepted: 10/12/2011] [Indexed: 02/06/2023] Open
Abstract
Antagonists of L-type Ca²⁺ channels (LTCCs) have been used to treat human cardiovascular diseases for decades. However, these inhibitors can have untoward effects in patients with heart failure, and their overall therapeutic profile remains nebulous given differential effects in the vasculature when compared with those in cardiomyocytes. To investigate this issue, we examined mice heterozygous for the gene encoding the pore-forming subunit of LTCC (calcium channel, voltage-dependent, L type, α1C subunit [Cacna1c mice; referred to herein as α1C⁻/⁺ mice]) and mice in which this gene was loxP targeted to achieve graded heart-specific gene deletion (termed herein α1C-loxP mice). Adult cardiomyocytes from the hearts of α1C⁻/⁺ mice at 10 weeks of age showed a decrease in LTCC current and a modest decrease in cardiac function, which we initially hypothesized would be cardioprotective. However, α1C⁻/⁺ mice subjected to pressure overload stimulation, isoproterenol infusion, and swimming showed greater cardiac hypertrophy, greater reductions in ventricular performance, and greater ventricular dilation than α1C⁺/⁺ controls. The same detrimental effects were observed in α1C-loxP animals with a cardiomyocyte-specific deletion of one allele. More severe reductions in α1C protein levels with combinatorial deleted alleles produced spontaneous cardiac hypertrophy before 3 months of age, with early adulthood lethality. Mechanistically, our data suggest that a reduction in LTCC current leads to neuroendocrine stress, with sensitized and leaky sarcoplasmic reticulum Ca²⁺ release as a compensatory mechanism to preserve contractility. This state results in calcineurin/nuclear factor of activated T cells signaling that promotes hypertrophy and disease.
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Affiliation(s)
- Sanjeewa A Goonasekera
- Department of Pediatrics, University of Cincinnati, Cincinnati Children's Hospital Medical Center, Howard Hughes Medical Institute, Cincinnati, Ohio 45229, USA
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Unraveling the secrets of a double life: contractile versus signaling Ca2+ in a cardiac myocyte. J Mol Cell Cardiol 2011; 52:317-22. [PMID: 21600216 DOI: 10.1016/j.yjmcc.2011.05.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2011] [Revised: 04/27/2011] [Accepted: 05/03/2011] [Indexed: 11/21/2022]
Abstract
No other inorganic molecule known in biology is considered as versatile as Ca(2+). In a vast majority of cell types, Ca(2+) acts as a universal second messenger underlying critical cellular processes varying from gene transcription to cell death. Although the role of Ca(2+) in myocyte contraction has been known for over a century, it was only more recently that this divalent cation has been implicated in mediating reactive signal transduction to promote cardiac hypertrophy. However, it remains unclear how Ca(2+)-dependent signaling pathways are regulated/activated in a cardiac myocyte given the prevailing conditions throughout the cytosol where Ca(2+) concentration oscillates between 100 nM and upwards of 1-2 μM during each contractile cycle. In this review we will examine three hypotheses put forward to explain how Ca(2+) might still function as a hypertrophic signaling molecule in cardiac myocytes and discuss the current literature that supports each of these views. This article is part of a special issue entitled "Local Signaling in Myocytes."
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van Oort RJ, Garbino A, Wang W, Dixit SS, Landstrom AP, Gaur N, De Almeida AC, Skapura DG, Rudy Y, Burns AR, Ackerman MJ, Wehrens XHT. Disrupted junctional membrane complexes and hyperactive ryanodine receptors after acute junctophilin knockdown in mice. Circulation 2011; 123:979-88. [PMID: 21339484 DOI: 10.1161/circulationaha.110.006437] [Citation(s) in RCA: 207] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Excitation-contraction coupling in striated muscle requires proper communication of plasmalemmal voltage-activated Ca2+ channels and Ca2+ release channels on sarcoplasmic reticulum within junctional membrane complexes. Although previous studies revealed a loss of junctional membrane complexes and embryonic lethality in germ-line junctophilin-2 (JPH2) knockout mice, it has remained unclear whether JPH2 plays an essential role in junctional membrane complex formation and the Ca(2+)-induced Ca(2+) release process in the heart. Our recent work demonstrated loss-of-function mutations in JPH2 in patients with hypertrophic cardiomyopathy. METHODS AND RESULTS To elucidate the role of JPH2 in the heart, we developed a novel approach to conditionally reduce JPH2 protein levels using RNA interference. Cardiac-specific JPH2 knockdown resulted in impaired cardiac contractility, which caused heart failure and increased mortality. JPH2 deficiency resulted in loss of excitation-contraction coupling gain, precipitated by a reduction in the number of junctional membrane complexes and increased variability in the plasmalemma-sarcoplasmic reticulum distance. CONCLUSIONS Loss of JPH2 had profound effects on Ca2+ release channel inactivation, suggesting a novel functional role for JPH2 in regulating intracellular Ca2+ release channels in cardiac myocytes. Thus, our novel approach of cardiac-specific short hairpin RNA-mediated knockdown of junctophilin-2 has uncovered a critical role for junctophilin in intracellular Ca2+ release in the heart.
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Affiliation(s)
- Ralph J van Oort
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA
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Three 4-letter words of hypertension-related cardiac hypertrophy: TRPC, mTOR, and HDAC. J Mol Cell Cardiol 2011; 50:964-71. [PMID: 21320507 DOI: 10.1016/j.yjmcc.2011.02.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Revised: 01/26/2011] [Accepted: 02/02/2011] [Indexed: 12/12/2022]
Abstract
Left ventricular hypertrophy due to hypertension represents a major risk factor for adverse cardiovascular events and death. In recent years, the prevalence of cardiac hypertrophy has increased due to obesity and an aging population. Notably, a significant number of individuals have persistent cardiac hypertrophy in the face of blood pressure that is normalized by drug treatment. Thus, a better understanding of the processes underlying the cardiac remodeling events that are set into play by hypertension is needed. At the level of the cardiac myocytes, hypertrophic growth is often described as physiological, as occurs with exercise, or pathological, as seen with hypertension. Here we discuss recent developments in three areas that are fundamental to pathological hypertrophic growth of cardiac myocytes. These areas are the transient receptor potential canonical (TRPC) channels, mammalian target of rapamycin (mTOR) complexes, and histone deacetylase (HDAC) enzymes. In the last several years, studies in each of these areas have yielded new and exciting discoveries into the genesis of pathological growth of cardiac myocytes. The phosphoinositide 3-kinase-Akt signaling network may be the common denominator that links these areas together. Defining the interrelationship among TRPC channels, mTOR signaling, and HDAC enzymes is a promising, but challenging area of research. Such knowledge will undoubtedly lead to new drugs that better prevent or reverse left ventricular hypertension.
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Dunn ME, Manfredi TG, Cosmas AC, Vetter FJ, King JN, Rodgers RL. Mechanical function, glycolysis, and ultrastructure of perfused working mouse hearts following thoracic aortic constriction. Cardiovasc Pathol 2011; 20:343-51. [PMID: 21296006 DOI: 10.1016/j.carpath.2010.12.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/02/2010] [Accepted: 12/13/2010] [Indexed: 10/18/2022] Open
Abstract
BACKGROUND Glycolytic flux in the mouse heart during the progression of left ventricular hypertrophy (LVH) and mechanical dysfunction has not been described. METHODS The main objectives of this study were to characterize the effects of thoracic aortic banding, of 3- and 6-week duration, on: (1) left ventricular (LV) systolic and diastolic function of perfused working hearts quantified by analysis of pressure-volume loops; (2) glycolytic flux in working hearts expressed as the rate of conversion of (3)H-glucose to (3)H(2)O, and (3) ultrastructure of LV biopsies assessed by quantitative and qualitative analysis of light and electron micrographs. RESULTS Results revealed that (1) indexes of systolic function, including LV end-systolic pressure, cardiac output, and rate of LV pressure development and decline, were depressed to similar degrees at 3 and 6 weeks post-banding; (2) diastolic dysfunction, represented by elevated LV end-diastolic pressure and volume, was more severe at 6 than at 3 weeks, consistent with a transition to failure; (3) a progressive decline in glycolytic flux that was roughly half the control rate by 6 weeks post-banding; and (4) structural derangements, manifested by increases in interstitial collagen content and myocyte Z-band disruption, that were more marked at 3 weeks than at 6 weeks. CONCLUSION The results are consistent with the view that myocyte damage, fibrosis, and suppressed glycolytic flux represent maladaptive structural and metabolic remodeling that contribute to the development of failure in high pressure load-induced LVH in the mouse.
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Affiliation(s)
- Michael E Dunn
- Department of Biomedical and Pharmaceutical Sciences, University of Rhode Island, Kingston, RI 02881, USA
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van Deel ED, de Boer M, Kuster DW, Boontje NM, Holemans P, Sipido KR, van der Velden J, Duncker DJ. Exercise training does not improve cardiac function in compensated or decompensated left ventricular hypertrophy induced by aortic stenosis. J Mol Cell Cardiol 2011; 50:1017-25. [PMID: 21291889 DOI: 10.1016/j.yjmcc.2011.01.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2010] [Revised: 01/11/2011] [Accepted: 01/22/2011] [Indexed: 01/14/2023]
Abstract
There is ample evidence that regular exercise exerts beneficial effects on left ventricular (LV) hypertrophy, remodeling and dysfunction produced by ischemic heart disease or systemic hypertension. In contrast, the effects of exercise on pathological LV hypertrophy and dysfunction produced by LV outflow obstruction have not been studied to date. Consequently, we evaluated the effects of 8 weeks of voluntary wheel running in mice (which mitigates post-infarct LV dysfunction) on LV hypertrophy and dysfunction produced by mild (mTAC) and severe (sTAC) transverse aortic constriction. mTAC produced ~40% LV hypertrophy and increased myocardial expression of hypertrophy marker genes but did not affect LV function, SERCA2a protein levels, apoptosis or capillary density. Exercise had no effect on global LV hypertrophy and function in mTAC but increased interstitial collagen, and ANP expression. sTAC produced ~80% LV hypertrophy and further increased ANP expression and interstitial fibrosis and, in contrast with mTAC, also produced LV dilation, systolic as well as diastolic dysfunction, pulmonary congestion, apoptosis and capillary rarefaction and decreased SERCA2a and ryanodine receptor (RyR) protein levels. LV diastolic dysfunction was likely aggravated by elevated passive isometric force and Ca(2+)-sensitivity of myofilaments. Exercise training failed to mitigate the sTAC-induced LV hypertrophy and capillary rarefaction or the decreases in SERCA2a and RyR. Exercise attenuated the sTAC-induced increase in passive isometric force but did not affect myofilament Ca(2+)-sensitivity and tended to aggravate interstitial fibrosis. In conclusion, exercise had no effect on LV function in compensated and decompensated cardiac hypertrophy produced by LV outflow obstruction, suggesting that the effect of exercise on pathologic LV hypertrophy and dysfunction depends critically on the underlying cause.
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Affiliation(s)
- Elza D van Deel
- Experimental Cardiology, Thoraxcenter, Cardiovascular Research School COEUR, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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van Oort RJ, McCauley MD, Dixit SS, Pereira L, Yang Y, Respress JL, Wang Q, De Almeida AC, Skapura DG, Anderson ME, Bers DM, Wehrens XHT. Ryanodine receptor phosphorylation by calcium/calmodulin-dependent protein kinase II promotes life-threatening ventricular arrhythmias in mice with heart failure. Circulation 2010; 122:2669-79. [PMID: 21098440 DOI: 10.1161/circulationaha.110.982298] [Citation(s) in RCA: 240] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND approximately half of patients with heart failure die suddenly as a result of ventricular arrhythmias. Although abnormal Ca(2+) release from the sarcoplasmic reticulum through ryanodine receptors (RyR2) has been linked to arrhythmogenesis, the molecular mechanisms triggering release of arrhythmogenic Ca(2+) remain unknown. We tested the hypothesis that increased RyR2 phosphorylation by Ca(2+)/calmodulin-dependent protein kinase II is both necessary and sufficient to promote lethal ventricular arrhythmias. METHODS AND RESULTS mice in which the S2814 Ca(2+)/calmodulin-dependent protein kinase II site on RyR2 is constitutively activated (S2814D) develop pathological sarcoplasmic reticulum Ca(2+) release events, resulting in reduced sarcoplasmic reticulum Ca(2+) load on confocal microscopy. These Ca(2+) release events are associated with increased RyR2 open probability in lipid bilayer preparations. At baseline, young S2814D mice have structurally and functionally normal hearts without arrhythmias; however, they develop sustained ventricular tachycardia and sudden cardiac death on catecholaminergic provocation by caffeine/epinephrine or programmed electric stimulation. Young S2814D mice have a significant predisposition to sudden arrhythmogenic death after transverse aortic constriction surgery. Finally, genetic ablation of the Ca(2+)/calmodulin-dependent protein kinase II site on RyR2 (S2814A) protects mutant mice from pacing-induced arrhythmias versus wild-type mice after transverse aortic constriction surgery. CONCLUSIONS our results suggest that Ca(2+)/calmodulin-dependent protein kinase II phosphorylation of RyR2 Ca(2+) release channels at S2814 plays an important role in arrhythmogenesis and sudden cardiac death in mice with heart failure.
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Affiliation(s)
- Ralph J van Oort
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, BCM335, Houston, TX 77030, USA
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Seidler T, Teucher N, Hellenkamp K, Unsöld B, Grebe C, Kramps P, Schotola H, Wagner S, Schöndube FA, Hasenfuss G, Maier LS. Limitations of FKBP12.6-directed treatment strategies for maladaptive cardiac remodeling and heart failure. J Mol Cell Cardiol 2010; 50:33-42. [PMID: 20797399 DOI: 10.1016/j.yjmcc.2010.08.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 08/16/2010] [Accepted: 08/17/2010] [Indexed: 11/29/2022]
Abstract
Sarcoplasmic reticulum (SR) calcium (Ca) leak can be reduced by enhancing FKBP12.6 binding to SR Ca release channels (RyR2) and expression of a "sticky" FKBP12.6(D37S) mutant may correct reduced binding stoichiometry in RyR2 from failing hearts. Both calcium/calmodulin-dependent protein kinase IIδc (CaMKIIδc) and protein kinase A (PKA) are activated in heart failure and promote SR Ca leak at RyR2. It is possible that FKBP12.6 dissociation from RyR2 may promote remodeling and that interventions to reassociate FKBP12.6 with RyR2 reflect a future therapeutic strategy. We created transgenic (TG) mice expressing FKBP12.6(D37S) and tested their capacity to improve intracellular Ca handling and pathological remodeling in vivo. FKBP12.6(D37S) TG mice were cross-bred with CaMKIIδc TG mice, which are known to exhibit pronounced RyR2 dysfunction and heart failure. We observed a significant improvement of post-rest Ca transients and a higher SR Ca content in FKBP12.6(D37S) TG mice. In double-TG mice, a marked reduction of SR Ca spark frequency indicated reduced SR Ca leak but neither SR Ca transient amplitude, SR Ca content nor morphological or functional parameters improved in vivo. Likewise, FKBP12.6(D37S) TG mice subjected to increased afterload after aortic banding exhibited higher SR Ca load but did not exhibit any improvement in hypertrophic growth or functional decline. Enhancement of FKBP12.6-RyR2 binding markedly reduced RyR2 Ca leak in CaMKIIδc-induced heart failure and in pressure overload. Our data suggest that activation of CaMKIIδc and pressure overload confer significant resistance towards approaches aiming at FKBP12.6-RyR2 reconstitution in heart failure and maladaptive remodeling, although RyR2 Ca leak can be reduced.
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Affiliation(s)
- Tim Seidler
- Department of Cardiology and Pneumology, Heart Center, University of Göttingen, Germany.
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