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Ronconi-Krüger N, Müller YMR, Nazari EM. Exploring developmental MeHg impact on extraembryonic and cardiac vessels and its effect on cardiomyocyte contractility. J Appl Toxicol 2024. [PMID: 38978343 DOI: 10.1002/jat.4661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 06/06/2024] [Accepted: 06/10/2024] [Indexed: 07/10/2024]
Abstract
The toxicity of methylmercury (MeHg) during embryonic development is a relevant issue that remains unclear and deserves investigation. In this sense, there is evidence that links the intake of contaminated food with cardiovascular pathologies in human adults and children. Thus, this study aimed to verify the impact of MeHg on the structure and integrity of extraembryonic and cardiac blood vessels and the contractile function of cardiomyocytes, also evaluating embryonic weight and the cardiosomatic index (CSI). Thus, chicken embryos, used as an experimental model, were exposed to a single dose of 0.1 μg MeHg/50 μl saline at E1.5 and analyzed at E10. After exposure, an increase in the number of extraembryonic blood vessels and the veins of the cardiac tissue was observed. These increases were accompanied by a reduction in the content of VEGF and VCAM proteins related to vessel growth and adhesiveness. Together, these results were related to reduced nitrite (NOx) levels. Furthermore, MeHg reduces the number of sarcomeres and increases the content of cardiac troponin I (cTnI), a protein that regulates contraction. In general, exposure to MeHg affected the integrity of extraembryonic and cardiac vessels and the contractile function of cardiomyocytes, which had a systemic impact evidenced by the reduction in embryonic weight gain and CSI.
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Affiliation(s)
- Nathália Ronconi-Krüger
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Yara Maria Rauh Müller
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
| | - Evelise Maria Nazari
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, Santa Catarina, Brazil
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2
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Guo J, Jiang H, Schuftan D, Moreno JD, Ramahdita G, Aryan L, Bhagavan D, Silva J, Huebsch N. Substrate mechanics unveil early structural and functional pathology in iPSC micro-tissue models of hypertrophic cardiomyopathy. iScience 2024; 27:109954. [PMID: 38827401 PMCID: PMC11141149 DOI: 10.1016/j.isci.2024.109954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/22/2024] [Accepted: 05/08/2024] [Indexed: 06/04/2024] Open
Abstract
Hypertension is a major cause of morbidity and mortality in patients with hypertrophic cardiomyopathy (HCM), suggesting a potential role for mechanics in HCM pathogenesis. Here, we developed an in vitro physiological model to investigate how mechanics acts together with HCM-linked myosin binding protein C (MYBPC3) mutations to trigger disease. Micro-heart muscles (μHM) were engineered from induced pluripotent stem cell (iPSC)-derived cardiomyocytes bearing MYBPC3+/- mutations and challenged to contract against substrates of different elasticity. μHMs that worked against substrates with stiffness at or exceeding the stiffness of healthy adult heart muscle exhibited several hallmarks of HCM, including cellular hypertrophy, impaired contractile energetics, and maladaptive calcium handling. Remarkably, we discovered changes in troponin C and T localization in MYBPC3+/- μHM that were entirely absent in 2D culture. Pharmacologic studies suggested that excessive Ca2+ intake through membrane-embedded channels underlie the observed electrophysiological abnormalities. These results illustrate the power of physiologically relevant engineered tissue models to study inherited disease with iPSC technology.
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Affiliation(s)
- Jingxuan Guo
- Department of Mechanical Engineering and Material Science, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Huanzhu Jiang
- Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - David Schuftan
- Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Jonathan D. Moreno
- Division of Cardiology, Department of Medicine, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Ghiska Ramahdita
- Department of Mechanical Engineering and Material Science, Washington University in Saint Louis, Saint Louis, MO 63130, USA
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Lavanya Aryan
- Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Druv Bhagavan
- Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Jonathan Silva
- Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO 63130, USA
| | - Nathaniel Huebsch
- Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO 63130, USA
- NSF Science and Technology Center for Engineering Mechanobiology, Washington University in Saint Louis, Saint Louis, MO 63130, USA
- Center for Cardiovascular Research, Center for Regenerative Medicine, Center for Investigation of Membrane Excitability Diseases, Washington University in Saint Louis, Saint Louis, MO 63130, USA
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3
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Cubuk J, Greenberg L, Greenberg AE, Emenecker RJ, Stuchell-Brereton MD, Holehouse AS, Soranno A, Greenberg MJ. Structural dynamics of the intrinsically disordered linker region of cardiac troponin T. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.30.596451. [PMID: 38853835 PMCID: PMC11160775 DOI: 10.1101/2024.05.30.596451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
The cardiac troponin complex, composed of troponins I, T, and C, plays a central role in regulating the calcium-dependent interactions between myosin and the thin filament. Mutations in troponin can cause cardiomyopathies; however, it is still a major challenge for the field to connect how changes in sequence affect troponin's function. Recent high-resolution structures of the thin filament revealed critical insights into the structure-function relationship of the troponin complex, but there remain large, unresolved segments of troponin, including the troponin-T linker region that is a hotspot for several cardiomyopathy mutations. This unresolved yet functionally-significant linker region has been proposed to be intrinsically disordered, with behaviors that are not well described by traditional structural approaches; however, this proposal has not been experimentally verified. Here, we used a combination of single-molecule Förster resonance energy transfer (FRET), molecular dynamics simulations, and functional reconstitution assays to investigate the troponin-T linker region. We experimentally and computationally show that in the context of both isolated troponin and the fully regulated troponin complex, the linker behaves as a dynamic, intrinsically disordered region. This region undergoes polyampholyte expansion in the presence of high salt and distinct conformational changes during the assembly of the troponin complex. We also examine the ΔE160 hypertrophic cardiomyopathy mutation in the linker, and we demonstrate that this mutation does not affect the conformational dynamics of the linker, rather it allosterically affects interactions with other subunits of the troponin complex, leading to increased molecular contractility. Taken together, our data clearly demonstrate the importance of disorder within the troponin-T linker and provide new insights into the molecular mechanisms controlling the pathogenesis of cardiomyopathies.
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Affiliation(s)
- Jasmine Cubuk
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130, Saint Louis, MO, USA
| | - Lina Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
| | - Akiva E. Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
| | - Ryan J. Emenecker
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130, Saint Louis, MO, USA
| | - Melissa D. Stuchell-Brereton
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130, Saint Louis, MO, USA
| | - Alex S. Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130, Saint Louis, MO, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130, Saint Louis, MO, USA
| | - Michael J. Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 Euclid Ave, 63110, Saint Louis, MO, USA
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Guo J, Jiang H, Schuftan D, Moreno JD, Ramahdita G, Aryan L, Bhagavan D, Silva J, Huebsch N. Mechanical Resistance to Micro-Heart Tissue Contractility unveils early Structural and Functional Pathology in iPSC Models of Hypertrophic Cardiomyopathy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.30.564856. [PMID: 37961198 PMCID: PMC10634965 DOI: 10.1101/2023.10.30.564856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Hypertrophic cardiomyopathy is the most common cause of sudden death in the young. Because the disease exhibits variable penetrance, there are likely nongenetic factors that contribute to the manifestation of the disease phenotype. Clinically, hypertension is a major cause of morbidity and mortality in patients with HCM, suggesting a potential synergistic role for the sarcomeric mutations associated with HCM and mechanical stress on the heart. We developed an in vitro physiological model to investigate how the afterload that the heart muscle works against during contraction acts together with HCM-linked MYBPC3 mutations to trigger a disease phenotype. Micro-heart muscle arrays (μHM) were engineered from iPSC-derived cardiomyocytes bearing MYBPC3 loss-of-function mutations and challenged to contract against mechanical resistance with substrates stiffnesses ranging from the of embryonic hearts (0.4 kPa) up to the stiffness of fibrotic adult hearts (114 kPa). Whereas MYBPC3 +/- iPSC-cardiomyocytes showed little signs of disease pathology in standard 2D culture, μHMs that included components of afterload revealed several hallmarks of HCM, including cellular hypertrophy, impaired contractile energetics, and maladaptive calcium handling. Remarkably, we discovered changes in troponin C and T localization in the MYBPC3 +/- μHM that were entirely absent in 2D culture. Pharmacologic studies suggested that excessive Ca 2+ intake through membrane-embedded channels, rather than sarcoplasmic reticulum Ca 2+ ATPase (SERCA) dysfunction or Ca 2+ buffering at myofilaments underlie the observed electrophysiological abnormalities. These results illustrate the power of physiologically relevant engineered tissue models to study inherited disease mechanisms with iPSC technology.
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Rivas VN, Kaplan JL, Kennedy SA, Fitzgerald S, Crofton AE, Farrell A, Grubb L, Jauregui CE, Grigorean G, Choi E, Harris SP, Stern JA. Multi-Omic, Histopathologic, and Clinicopathologic Effects of Once-Weekly Oral Rapamycin in a Naturally Occurring Feline Model of Hypertrophic Cardiomyopathy: A Pilot Study. Animals (Basel) 2023; 13:3184. [PMID: 37893908 PMCID: PMC10603660 DOI: 10.3390/ani13203184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) remains the single most common cardiomyopathy in cats, with a staggering prevalence as high as 15%. To date, little to no direct therapeutical intervention for HCM exists for veterinary patients. A previous study aimed to evaluate the effects of delayed-release (DR) rapamycin dosing in a client-owned population of subclinical, non-obstructive, HCM-affected cats and reported that the drug was well tolerated and resulted in beneficial LV remodeling. However, the precise effects of rapamycin in the hypertrophied myocardium remain unknown. Using a feline research colony with naturally occurring hereditary HCM (n = 9), we embarked on the first-ever pilot study to examine the tissue-, urine-, and plasma-level proteomic and tissue-level transcriptomic effects of an intermittent low dose (0.15 mg/kg) and high dose (0.30 mg/kg) of DR oral rapamycin once weekly. Rapamycin remained safe and well tolerated in cats receiving both doses for eight weeks. Following repeated weekly dosing, transcriptomic differences between the low- and high-dose groups support dose-responsive suppressive effects on myocardial hypertrophy and stimulatory effects on autophagy. Differences in the myocardial proteome between treated and control cats suggest potential anti-coagulant/-thrombotic, cellular remodeling, and metabolic effects of the drug. The results of this study closely recapitulate what is observed in the human literature, and the use of rapamycin in the clinical setting as the first therapeutic agent with disease-modifying effects on HCM remains promising. The results of this study establish the need for future validation efforts that investigate the fine-scale relationship between rapamycin treatment and the most compelling gene expression and protein abundance differences reported here.
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Affiliation(s)
- Victor N. Rivas
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Joanna L. Kaplan
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | | | | | - Amanda E. Crofton
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
| | | | | | - Carina E. Jauregui
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
| | - Gabriela Grigorean
- Proteomics Core Facility, University of California-Davis, Davis, CA 95616, USA
| | - Eunju Choi
- Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA;
| | - Samantha P. Harris
- Department of Physiology, College of Medicine-Tucson, University of Arizona, Tucson, AZ 85724, USA
| | - Joshua A. Stern
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27607, USA
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6
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Tikunova SB, Thuma J, Davis JP. Mouse Models of Cardiomyopathies Caused by Mutations in Troponin C. Int J Mol Sci 2023; 24:12349. [PMID: 37569724 PMCID: PMC10419064 DOI: 10.3390/ijms241512349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 07/27/2023] [Accepted: 08/01/2023] [Indexed: 08/13/2023] Open
Abstract
Cardiac muscle contraction is regulated via Ca2+ exchange with the hetero-trimeric troponin complex located on the thin filament. Binding of Ca2+ to cardiac troponin C, a Ca2+ sensing subunit within the troponin complex, results in a series of conformational re-arrangements among the thin filament components, leading to an increase in the formation of actomyosin cross-bridges and muscle contraction. Ultimately, a decline in intracellular Ca2+ leads to the dissociation of Ca2+ from troponin C, inhibiting cross-bridge cycling and initiating muscle relaxation. Therefore, troponin C plays a crucial role in the regulation of cardiac muscle contraction and relaxation. Naturally occurring and engineered mutations in troponin C can lead to altered interactions among components of the thin filament and to aberrant Ca2+ binding and exchange with the thin filament. Mutations in troponin C have been associated with various forms of cardiac disease, including hypertrophic, restrictive, dilated, and left ventricular noncompaction cardiomyopathies. Despite progress made to date, more information from human studies, biophysical characterizations, and animal models is required for a clearer understanding of disease drivers that lead to cardiomyopathies. The unique use of engineered cardiac troponin C with the L48Q mutation that had been thoroughly characterized and genetically introduced into mouse myocardium clearly demonstrates that Ca2+ sensitization in and of itself should not necessarily be considered a disease driver. This opens the door for small molecule and protein engineering strategies to help boost impaired systolic function. On the other hand, the engineered troponin C mutants (I61Q and D73N), genetically introduced into mouse myocardium, demonstrate that Ca2+ desensitization under basal conditions may be a driving factor for dilated cardiomyopathy. In addition to enhancing our knowledge of molecular mechanisms that trigger hypertrophy, dilation, morbidity, and mortality, these cardiomyopathy mouse models could be used to test novel treatment strategies for cardiovascular diseases. In this review, we will discuss (1) the various ways mutations in cardiac troponin C might lead to disease; (2) relevant data on mutations in cardiac troponin C linked to human disease, and (3) all currently existing mouse models containing cardiac troponin C mutations (disease-associated and engineered).
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Affiliation(s)
- Svetlana B. Tikunova
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, College of Medicine, The Ohio State University, Columbus, OH 43210, USA (J.P.D.)
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Lillo R, Graziani F, Franceschi F, Iannaccone G, Massetti M, Olivotto I, Crea F, Liuzzo G. Inflammation across the spectrum of hypertrophic cardiac phenotypes. Heart Fail Rev 2023:10.1007/s10741-023-10307-4. [PMID: 37115472 PMCID: PMC10403403 DOI: 10.1007/s10741-023-10307-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/26/2023] [Indexed: 04/29/2023]
Abstract
The hypertrophic cardiomyopathy phenotype encompasses a heterogeneous spectrum of genetic and acquired diseases characterized by the presence of left ventricular hypertrophy in the absence of abnormal cardiac loading conditions. This "umbrella diagnosis" includes the "classic" hypertrophic cardiomyopathy (HCM), due to sarcomere protein gene mutations, and its phenocopies caused by intra- or extracellular deposits, such as Fabry disease (FD) and cardiac amyloidosis (CA). All these conditions share a wide phenotypic variability which results from the combination of genetic and environmental factors and whose pathogenic mediators are poorly understood so far. Accumulating evidence suggests that inflammation plays a critical role in a broad spectrum of cardiovascular conditions, including cardiomyopathies. Indeed, inflammation can trigger molecular pathways which contribute to cardiomyocyte hypertrophy and dysfunction, extracellular matrix accumulation, and microvascular dysfunction. Growing evidence suggests that systemic inflammation is a possible key pathophysiologic process potentially involved in the pathogenesis of cardiac disease progression, influencing the severity of the phenotype and clinical outcome, including heart failure. In this review, we summarize current knowledge regarding the prevalence, clinical significance, and potential therapeutic implications of inflammation in HCM and two of its most important phenocopies, FD and CA.
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Affiliation(s)
- Rosa Lillo
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome, 00168, Italy
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, Rome, Italy
| | - Francesca Graziani
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome, 00168, Italy.
| | - Francesco Franceschi
- Department of Emergency Medicine, Fondazione Policlinico Universitario A. Gemelli IRCCS, Catholic University of the Sacred Heart, Rome, Italy
| | - Giulia Iannaccone
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome, 00168, Italy
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, Rome, Italy
| | - Massimo Massetti
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome, 00168, Italy
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, Rome, Italy
| | - Iacopo Olivotto
- Cardiology Unit, Meyer Children's Hospital IRCCS, Florence, Italy
| | - Filippo Crea
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome, 00168, Italy
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, Rome, Italy
| | - Giovanna Liuzzo
- Department of Cardiovascular Sciences, Fondazione Policlinico Universitario A. Gemelli IRCCS, Largo A. Gemelli 8, Rome, 00168, Italy
- Department of Cardiovascular and Pulmonary Sciences, Catholic University of the Sacred Heart, Rome, Italy
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Langa P, Marszalek RJ, Warren CM, Chowdhury SK, Halas M, Batra A, Rafael-Clyke K, Bacon A, Goldspink PH, Solaro RJ, Wolska BM. Altered coronary artery function, arteriogenesis and endothelial YAP signaling in postnatal hypertrophic cardiomyopathy. Front Physiol 2023; 14:1136852. [PMID: 37064918 PMCID: PMC10102353 DOI: 10.3389/fphys.2023.1136852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 03/13/2023] [Indexed: 04/03/2023] Open
Abstract
Introduction: Hypertrophic cardiomyopathy (HCM) is a cardiovascular genetic disease caused largely by sarcomere protein mutations. Gaps in our understanding exist as to how maladaptive sarcomeric biophysical signals are transduced to intra- and extracellular compartments leading to HCM progression. To investigate early HCM progression, we focused on the onset of myofilament dysfunction during neonatal development and examined cardiac dynamics, coronary vascular structure and function, and mechano-transduction signaling in mice harboring a thin-filament HCM mutation. Methods: We studied postnatal days 7-28 (P7-P28) in transgenic (TG) TG-cTnT-R92Q and non-transgenic (NTG) mice using skinned fiber mechanics, echocardiography, biochemistry, histology, and immunohistochemistry. Results: At P7, skinned myofiber bundles exhibited an increased Ca2+-sensitivity (pCa50 TG: 5.97 ± 0.04, NTG: 5.84 ± 0.01) resulting from cTnT-R92Q expression on a background of slow skeletal (fetal) troponin I and α/β myosin heavy chain isoform expression. Despite the transition to adult isoform expressions between P7-P14, the increased Ca2+- sensitivity persisted through P28 with no apparent differences in gross morphology among TG and NTG hearts. At P7 significant diastolic dysfunction was accompanied by coronary flow perturbation (mean diastolic velocity, TG: 222.5 ± 18.81 mm/s, NTG: 338.7 ± 28.07 mm/s) along with localized fibrosis (TG: 4.36% ± 0.44%, NTG: 2.53% ± 0.47%). Increased phosphorylation of phospholamban (PLN) was also evident indicating abnormalities in Ca2+ homeostasis. By P14 there was a decline in arteriolar cross-sectional area along with an expansion of fibrosis (TG: 9.72% ± 0.73%, NTG: 2.72% ± 0.2%). In comparing mechano-transduction signaling in the coronary arteries, we uncovered an increase in endothelial YAP expression with a decrease in its nuclear to cytosolic ratio at P14 in TG hearts, which was reversed by P28. Conclusion: We conclude that those early mechanisms that presage hypertrophic remodeling in HCM include defective biophysical signals within the sarcomere that drive diastolic dysfunction, impacting coronary flow dynamics, defective arteriogenesis and fibrosis. Changes in mechano-transduction signaling between the different cellular compartments contribute to the pathogenesis of HCM.
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Affiliation(s)
- Paulina Langa
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Richard J. Marszalek
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Chad M. Warren
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Shamim K. Chowdhury
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Monika Halas
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Ashley Batra
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Koreena Rafael-Clyke
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Angelie Bacon
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Paul H. Goldspink
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - R. John Solaro
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Beata M. Wolska
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- Department of Medicine, Division of Cardiology, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
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9
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Pioner JM, Vitale G, Steczina S, Langione M, Margara F, Santini L, Giardini F, Lazzeri E, Piroddi N, Scellini B, Palandri C, Schuldt M, Spinelli V, Girolami F, Mazzarotto F, van der Velden J, Cerbai E, Tesi C, Olivotto I, Bueno-Orovio A, Sacconi L, Coppini R, Ferrantini C, Regnier M, Poggesi C. Slower Calcium Handling Balances Faster Cross-Bridge Cycling in Human MYBPC3 HCM. Circ Res 2023; 132:628-644. [PMID: 36744470 PMCID: PMC9977265 DOI: 10.1161/circresaha.122.321956] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 01/19/2023] [Accepted: 01/24/2023] [Indexed: 02/07/2023]
Abstract
BACKGROUND The pathogenesis of MYBPC3-associated hypertrophic cardiomyopathy (HCM) is still unresolved. In our HCM patient cohort, a large and well-characterized population carrying the MYBPC3:c772G>A variant (p.Glu258Lys, E258K) provides the unique opportunity to study the basic mechanisms of MYBPC3-HCM with a comprehensive translational approach. METHODS We collected clinical and genetic data from 93 HCM patients carrying the MYBPC3:c772G>A variant. Functional perturbations were investigated using different biophysical techniques in left ventricular samples from 4 patients who underwent myectomy for refractory outflow obstruction, compared with samples from non-failing non-hypertrophic surgical patients and healthy donors. Human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes and engineered heart tissues (EHTs) were also investigated. RESULTS Haplotype analysis revealed MYBPC3:c772G>A as a founder mutation in Tuscany. In ventricular myocardium, the mutation leads to reduced cMyBP-C (cardiac myosin binding protein-C) expression, supporting haploinsufficiency as the main primary disease mechanism. Mechanical studies in single myofibrils and permeabilized muscle strips highlighted faster cross-bridge cycling, and higher energy cost of tension generation. A novel approach based on tissue clearing and advanced optical microscopy supported the idea that the sarcomere energetics dysfunction is intrinsically related with the reduction in cMyBP-C. Studies in single cardiomyocytes (native and hiPSC-derived), intact trabeculae and hiPSC-EHTs revealed prolonged action potentials, slower Ca2+ transients and preserved twitch duration, suggesting that the slower excitation-contraction coupling counterbalanced the faster sarcomere kinetics. This conclusion was strengthened by in silico simulations. CONCLUSIONS HCM-related MYBPC3:c772G>A mutation invariably impairs sarcomere energetics and cross-bridge cycling. Compensatory electrophysiological changes (eg, reduced potassium channel expression) appear to preserve twitch contraction parameters, but may expose patients to greater arrhythmic propensity and disease progression. Therapeutic approaches correcting the primary sarcomeric defects may prevent secondary cardiomyocyte remodeling.
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Affiliation(s)
- Josè Manuel Pioner
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
- Department of Biology (J.M.P.), University of Florence, Italy
| | - Giulia Vitale
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Sonette Steczina
- Department of Bioengineering, University of Washington, Seattle, WA (S.S., M.R.)
| | - Marianna Langione
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Francesca Margara
- Department of Computer Science, University of Oxford, United Kingdom (F. Margara, A.B.-O.)
| | - Lorenzo Santini
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Francesco Giardini
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Erica Lazzeri
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Nicoletta Piroddi
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Beatrice Scellini
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Chiara Palandri
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Maike Schuldt
- Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Physiology, The Netherlands (M.S., J.v.d.V.)
| | - Valentina Spinelli
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Francesca Girolami
- Pediatric Cardiology (F. Girolami), IRCCS Meyer Children’s Hospital, Florence, Italy
| | - Francesco Mazzarotto
- Department of Molecular and Translational Medicine, University of Brescia, Italy (F. Mazzarotto)
- National Heart and Lung Institute, Imperial College London, London, United Kingdom (F. Mazzarotto)
| | - Jolanda van der Velden
- Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Physiology, The Netherlands (M.S., J.v.d.V.)
| | - Elisabetta Cerbai
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Chiara Tesi
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
| | - Iacopo Olivotto
- Cardiogenetics Unit (I.O.), IRCCS Meyer Children’s Hospital, Florence, Italy
- Referral Center for Cardiomyopathies, Careggi University Hospital, Florence, Italy (I.O.)
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, United Kingdom (F. Margara, A.B.-O.)
| | - Leonardo Sacconi
- Institute of Clinical Physiology (IFC), National Research Council, Florence, Italy (L. Sacconi)
- Institute for Experimental Cardiovascular Medicine, Faculty of Medicine, University of Freiburg (L. Sacconi)
| | - Raffaele Coppini
- Department of NeuroFarBa (L. Santini, C. Palandri, V. Spinelli, E. Cerbai, R. Coppini), University of Florence, Italy
| | - Cecilia Ferrantini
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA (S.S., M.R.)
| | - Corrado Poggesi
- Department of Clinical and Experimental Medicine, Division of Physiology (J.M.P., G.V., M.L., N.P., B.S., C.T., C.F., C. Poggesi), University of Florence, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS) (F. Giardini, E. Lazzeri, C.F., C.P., E. Cerbai), University of Florence, Italy
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10
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Argirò A, Zampieri M, Dei LL, Ferrantini C, Marchi A, Tomberli A, Baldini K, Cappelli F, Favilli S, Passantino S, Zocchi C, Tassetti L, Gabriele M, Maurizi N, Marchionni N, Coppini R, Olivotto I. Safety and efficacy of ranolazine in hypertrophic cardiomyopathy: Real-world experience in a National Referral Center. Int J Cardiol 2023; 370:271-278. [PMID: 36228766 DOI: 10.1016/j.ijcard.2022.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 10/03/2022] [Accepted: 10/06/2022] [Indexed: 11/05/2022]
Abstract
OBJECTIVES We assessed the efficacy and safety of ranolazine in real-world patients with hypertrophic cardiomyopathy (HCM). BACKGROUND Ranolazine is an anti-anginal drug that inhibits the late phase of the inward sodium current. In a small prospective trial, ranolazine reduced the arrhythmic burden and improved biomarker profile in HCM patients. However, systematic reports reflecting real-world use in this setting are lacking. METHODS Changes in clinical and instrumental features, symptoms and arrhythmic burden were evaluated in 119 patients with HCM before and during treatment with ranolazine at a national referral centre for HCM. RESULTS Patients were treated with ranolazine for 2 [1-4] years; 83 (70%) achieved a dosage ≥1000 mg per day. Treatment interruption was necessary in 24 patients (20%) due to side effects (n = 10, 8%) or disopyramide initiation (n = 8, 7%). Seventy patients (59%) were treated with ranolazine for relief of angina. Among them, 51 (73%) had total symptomatic relief and 47 patients (67%) showed ≥2 Canadian Cardiovascular society (CCS) angina grade improvement. Sixteen patients (13%) were treated for recurrent ventricular arrhythmias, including 4 with a clear ischemic trigger, who experienced no further arrhythmic episodes while on ranolazine. Finally, 33 patients (28%) were treated for heart failure associated with severe diastolic dysfunction: no symptomatic benefit could be observed in this group. CONCLUSION Ranolazine was safe and well tolerated in patients with HCM. The use of ranolazine may be considered in patients with HCM and microvascular angina.
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Affiliation(s)
- Alessia Argirò
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Mattia Zampieri
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy.
| | - Lorenzo-Lupo Dei
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy; Cardiology, Health and Environmental Science
- , University of L'Aquila, L'Aquila, Italy
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Alberto Marchi
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Alessia Tomberli
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Katia Baldini
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Francesco Cappelli
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | | | | | - Chiara Zocchi
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Luigi Tassetti
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Martina Gabriele
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | - Niccolò Maurizi
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy; Service of Cardiology, University Hospital of Lausanne, Switzerland
| | - Niccolò Marchionni
- Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
| | | | - Iacopo Olivotto
- Cardiomyopathy Unit, Cardiothoracovascular Department, Careggi University Hospital, Florence, Italy
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11
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Girolami F, Spinelli V, Maurizi N, Focardi M, Nesi G, Maio V, Grifoni R, Albora G, Bertaccini B, Targetti M, Coppini R, Favilli S, Olivotto I, Cerbai E. Genetic characterization of juvenile sudden cardiac arrest and death in Tuscany: The ToRSADE registry. Front Cardiovasc Med 2022; 9:1080608. [PMID: 36588553 PMCID: PMC9795053 DOI: 10.3389/fcvm.2022.1080608] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
Background Sudden cardiac arrest (SCA) in young people represents a dramatic event, often leading to severe neurologic outcomes or sudden cardiac death (SCD), and is frequently caused by genetic heart diseases. In this study, we report the results of the Tuscany registry of sudden cardiac death (ToRSADE) registry, aimed at monitoring the incidence and investigating the genetic basis of SCA and SCD occurring in subjects < 50 years of age in Tuscany, Italy. Methods and results Creation of the ToRSADE registry allowed implementation of a repository for clinical, molecular and genetic data. For 22 patients, in whom a genetic substrate was documented or suspected, blood samples could be analyzed; 14 were collected at autopsy and 8 from resuscitated patients after SCA. Next generation sequencing (NGS) analysis revealed likely pathogenetic (LP) variants associated with cardiomyopathy (CM) or channelopathy in four patients (19%), while 17 (81%) carried variants of uncertain significance in relevant genes (VUS). In only one patient NGS confirmed the diagnosis obtained during autopsy: the p.(Asn480Lysfs*20) PKP2 mutation in a patient with arrhythmogenic cardiomyopathy (AC). Conclusion Systematic genetic screening allowed identification of LP variants in 19% of consecutive patients with SCA/SCD, including subjects carrying variants associated with hypertrophic cardiomyopathy (HCM) or AC who had SCA/SCD in the absence of structural cardiomyopathy phenotype. Genetic analysis combined with clinical information in survived patients and post-mortem evaluation represent an essential multi-disciplinary approach to manage juvenile SCD and SCA, key to providing appropriate medical and genetic assistance to families, and advancing knowledge on the basis of arrhythmogenic mechanisms in inherited cardiomyopathies and channelopathies.
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Affiliation(s)
- Francesca Girolami
- Cardiology Unit, Meyer Children’s University Hospital, Florence, Italy,*Correspondence: Francesca Girolami,
| | - Valentina Spinelli
- Department of Neurosciences, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | | | - Martina Focardi
- Careggi University Hospital, Florence, Italy,Forensic Medical Sciences, Department of Health Sciences, University of Florence, Florence, Italy
| | - Gabriella Nesi
- Careggi University Hospital, Florence, Italy,Division of Pathological Anatomy, Department of Health Sciences, University of Florence, Florence, Italy
| | - Vincenza Maio
- Careggi University Hospital, Florence, Italy,Division of Pathological Anatomy, Department of Health Sciences, University of Florence, Florence, Italy
| | - Rossella Grifoni
- Careggi University Hospital, Florence, Italy,Forensic Medical Sciences, Department of Health Sciences, University of Florence, Florence, Italy
| | | | - Bruno Bertaccini
- Department of Statistics, Computer Science, Applications, University of Florence, Florence, Italy
| | | | - Raffaele Coppini
- Department of Neurosciences, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
| | - Silvia Favilli
- Cardiology Unit, Meyer Children’s University Hospital, Florence, Italy
| | - Iacopo Olivotto
- Cardiology Unit, Meyer Children’s University Hospital, Florence, Italy,Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Elisabetta Cerbai
- Department of Neurosciences, Psychology, Drug Research and Child Health, University of Florence, Florence, Italy
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12
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Kopylova GV, Matyushenko AM, Kochurova AM, Bershitsky SY, Shchepkin DV. Effects of Phosphorylation of Tropomyosin with Cardiomyopathic Mutations on Calcium Regulation of Myocardial Contraction. J EVOL BIOCHEM PHYS+ 2022. [DOI: 10.1134/s0022093022070092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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13
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Pioner JM, Santini L, Palandri C, Langione M, Grandinetti B, Querceto S, Martella D, Mazzantini C, Scellini B, Giammarino L, Lupi F, Mazzarotto F, Gowran A, Rovina D, Santoro R, Pompilio G, Tesi C, Parmeggiani C, Regnier M, Cerbai E, Mack DL, Poggesi C, Ferrantini C, Coppini R. Calcium handling maturation and adaptation to increased substrate stiffness in human iPSC-derived cardiomyocytes: The impact of full-length dystrophin deficiency. Front Physiol 2022; 13:1030920. [PMID: 36419836 PMCID: PMC9676373 DOI: 10.3389/fphys.2022.1030920] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/14/2022] [Indexed: 11/09/2022] Open
Abstract
Cardiomyocytes differentiated from human induced Pluripotent Stem Cells (hiPSC- CMs) are a unique source for modelling inherited cardiomyopathies. In particular, the possibility of observing maturation processes in a simple culture dish opens novel perspectives in the study of early-disease defects caused by genetic mutations before the onset of clinical manifestations. For instance, calcium handling abnormalities are considered as a leading cause of cardiomyocyte dysfunction in several genetic-based dilated cardiomyopathies, including rare types such as Duchenne Muscular Dystrophy (DMD)-associated cardiomyopathy. To better define the maturation of calcium handling we simultaneously measured action potential and calcium transients (Ca-Ts) using fluorescent indicators at specific time points. We combined micropatterned substrates with long-term cultures to improve maturation of hiPSC-CMs (60, 75 or 90 days post-differentiation). Control-(hiPSC)-CMs displayed increased maturation over time (90 vs 60 days), with longer action potential duration (APD), increased Ca-T amplitude, faster Ca-T rise (time to peak) and Ca-T decay (RT50). The progressively increased contribution of the SR to Ca release (estimated by post-rest potentiation or Caffeine-induced Ca-Ts) appeared as the main determinant of the progressive rise of Ca-T amplitude during maturation. As an example of severe cardiomyopathy with early onset, we compared hiPSC-CMs generated from a DMD patient (DMD-ΔExon50) and a CRISPR-Cas9 genome edited cell line isogenic to the healthy control with deletion of a G base at position 263 of the DMD gene (c.263delG-CMs). In DMD-hiPSC-CMs, changes of Ca-Ts during maturation were less pronounced: indeed, DMD cells at 90 days showed reduced Ca-T amplitude and faster Ca-T rise and RT50, as compared with control hiPSC-CMs. Caffeine-Ca-T was reduced in amplitude and had a slower time course, suggesting lower SR calcium content and NCX function in DMD vs control cells. Nonetheless, the inotropic and lusitropic responses to forskolin were preserved. CRISPR-induced c.263delG-CM line recapitulated the same developmental calcium handling alterations observed in DMD-CMs. We then tested the effects of micropatterned substrates with higher stiffness. In control hiPSC-CMs, higher stiffness leads to higher amplitude of Ca-T with faster decay kinetics. In hiPSC-CMs lacking full-length dystrophin, however, stiffer substrates did not modify Ca-Ts but only led to higher SR Ca content. These findings highlighted the inability of dystrophin-deficient cardiomyocytes to adjust their calcium homeostasis in response to increases of extracellular matrix stiffness, which suggests a mechanism occurring during the physiological and pathological development (i.e. fibrosis).
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Affiliation(s)
| | - Lorenzo Santini
- Department of Neurofarba, University of Florence, Florence, Italy
| | - Chiara Palandri
- Department of Neurofarba, University of Florence, Florence, Italy
| | - Marianna Langione
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Bruno Grandinetti
- European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Florence, Italy
| | - Silvia Querceto
- European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Florence, Italy
| | - Daniele Martella
- European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Florence, Italy
- Istituto Nazionale di Ricerca Metrologica (INRiM), Turin, Italy
| | | | - Beatrice Scellini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | | | - Flavia Lupi
- European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Florence, Italy
| | - Francesco Mazzarotto
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Aoife Gowran
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Davide Rovina
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Rosaria Santoro
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
| | - Giulio Pompilio
- Unit of Vascular Biology and Regenerative Medicine, Centro Cardiologico Monzino IRCCS, Milan, Italy
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Chiara Tesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Camilla Parmeggiani
- European Laboratory for Non-Linear Spectroscopy (LENS), University of Florence, Florence, Italy
- Department of Chemistry “Ugo Schiff”, University of Florence, Florence, Italy
| | - Michael Regnier
- Department of Bioengineering, University of Washington, Seattle, WA, United States
| | | | - David L. Mack
- Department of Bioengineering, University of Washington, Seattle, WA, United States
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Raffaele Coppini
- Department of Neurofarba, University of Florence, Florence, Italy
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14
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Sewanan LR, Shimada YJ. Prospects for remodeling the hypertrophic heart with myosin modulators. Front Cardiovasc Med 2022; 9:1051564. [DOI: 10.3389/fcvm.2022.1051564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 10/06/2022] [Indexed: 11/13/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a complex but relatively common genetic disease that usually arises from pathogenic variants that disrupt sarcomere function and lead to variable structural, hypertrophic, and fibrotic remodeling of the heart which result in substantial adverse clinical outcomes including arrhythmias, heart failure, and sudden cardiac death. HCM has had few effective treatments with the potential to ameliorate disease progression until the recent advent of inhibitory myosin modulators like mavacamten. Preclinical investigations and clinical trials utilizing this treatment targeted to this specific pathophysiological mechanism of sarcomere hypercontractility in HCM have confirmed that myosin modulators can alter disease expression and attenuate hypertrophic remodeling. Here, we summarize the state of hypertrophic remodeling and consider the arguments for and against salutary HCM disease modification using targeted myosin modulators. Further, we consider critical unanswered questions for future investigative and therapeutic avenues in HCM disease modification. We are at the precipice of a new era in understanding and treating HCM, with the potential to target agents toward modifying disease expression and natural history of this most common inherited disease of the heart.
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15
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Tamargo J, Tamargo M, Caballero R. Hypertrophic cardiomyopathy: an up-to-date snapshot of the clinical drug development pipeline. Expert Opin Investig Drugs 2022; 31:1027-1052. [PMID: 36062808 DOI: 10.1080/13543784.2022.2113374] [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: 11/04/2022]
Abstract
INTRODUCTION Hypertrophic cardiomyopathy (HCM) is a complex cardiac disease with highly variable phenotypic expression and clinical course most often caused by sarcomeric gene mutations resulting in left ventricular hypertrophy, fibrosis, hypercontractility, and diastolic dysfunction. For almost 60 years, HCM has remained an orphan disease and still lacks a disease-specific treatment. AREAS COVERED This review summarizes recent preclinical and clinical trials with repurposed drugs and new emerging pharmacological and gene-based therapies for the treatment of HCM. EXPERT OPINION The off-label drugs routinely used alleviate symptoms but do not target the core pathophysiology of HCM or prevent or revert the phenotype. Recent advances in the genetics and pathophysiology of HCM led to the development of cardiac myosin adenosine triphosphatase inhibitors specifically directed to counteract the hypercontractility associated with HCM-causing mutations. Mavacamten, the first drug specifically developed for HCM successfully tested in a phase 3 trial, represents the major advance for the treatment of HCM. This opens new horizons for the development of novel drugs targeting HCM molecular substrates which hopefully modify the natural history of the disease. The role of current drugs in development and genetic-based approaches for the treatment of HCM are also discussed.
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Affiliation(s)
- Juan Tamargo
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, 28040 Madrid, Spain
| | - María Tamargo
- Department of Cardiology, Hospital Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, Doctor Esquerdo, 46, 28007 Madrid, Spain
| | - Ricardo Caballero
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense, Instituto de Investigación Sanitaria Gregorio Marañón, CIBERCV, 28040 Madrid, Spain
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16
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Deranek AE, Baldo AP, Lynn ML, Schwartz SD, Tardiff JC. Structure and Dynamics of the Flexible Cardiac Troponin T Linker Domain in a Fully Reconstituted Thin Filament. Biochemistry 2022; 61:1229-1242. [PMID: 35696530 DOI: 10.1021/acs.biochem.2c00091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structural analysis of large protein complexes has been greatly enhanced through the application of electron microscopy techniques. One such multiprotein complex, the cardiac thin filament (cTF), has cyclic interactions with thick filament proteins to drive contraction of the heart that has recently been the subject of such studies. As important as these studies are, they provide limited or no information on highly flexible regions that in isolation would be characterized as inherently disordered. One such region is the extended cardiac troponin T (cTnT) linker between the regions of cTnT which have been labeled TNT1 and TNT2. It comprises a hinge region (residues 158-166) and a highly flexible region (residues 167-203). Critically, this region modulates the troponin/tropomyosin complex's position across the actin filament. Thus, the cTnT linker structure and dynamics are central to the regulation of the function of cardiac muscles, but up to now, it was ill-understood. To establish the cTnT linker structure, we coupled an atomistic computational cTF model with time-resolved fluorescence resonance energy transfer measurements in both ±Ca2+ conditions utilizing fully reconstituted cTFs. We mapped the cTnT linker's positioning across the actin filament, and by coupling the experimental results to computation, we found mean structures and ranges of motion of this part of the complex. With this new insight, we can now address cTnT linker structural dynamics in both myofilament activation and disease.
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Affiliation(s)
- Andrea E Deranek
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Anthony P Baldo
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Melissa L Lynn
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
| | - Steven D Schwartz
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Jil C Tardiff
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona 85721, United States
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17
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Abstract
Hypertrophic cardiomyopathy (HCM), the most common inherited heart disease, is still orphan of a specific drug treatment. The erroneous consideration of HCM as a rare disease has hampered the design and conduct of large, randomized trials in the last 50 years, and most of the indications in the current guidelines are derived from small non-randomized studies, case series, or simply from the consensus of experts. Guideline-directed therapy of HCM includes non-selective drugs such as disopyramide, non-dihydropyridine calcium channel blockers, or β-adrenergic receptor blockers, mainly used in patients with symptomatic obstruction of the outflow tract. Following promising preclinical studies, several drugs acting on potential HCM-specific targets were tested in patients. Despite the huge efforts, none of these studies was able to change clinical practice for HCM patients, because tested drugs were proven to be scarcely effective or hardly tolerated in patients. However, novel compounds have been developed in recent years specifically for HCM, addressing myocardial hypercontractility and altered energetics in a direct manner, through allosteric inhibition of myosin. In this paper, we will critically review the use of different classes of drugs in HCM patients, starting from "old" established agents up to novel selective drugs that have been recently trialed in patients.
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18
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Coppini R, Beltrami M, Doste R, Bueno-Orovio A, Ferrantini C, Vitale G, Pioner JM, Santini L, Argirò A, Berteotti M, Mori F, Marchionni N, Stefàno P, Cerbai E, Poggesi C, Olivotto I. Paradoxical prolongation of QT interval during exercise in patients with hypertrophic cardiomyopathy: cellular mechanisms and implications for diastolic function. EUROPEAN HEART JOURNAL OPEN 2022; 2:oeac034. [PMID: 35919344 PMCID: PMC9242073 DOI: 10.1093/ehjopen/oeac034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 04/14/2022] [Indexed: 11/21/2022]
Abstract
Aims Ventricular cardiomyocytes from hypertrophic cardiomyopathy (HCM) patient hearts show prolonged action potential duration (APD), impaired intracellular Ca2+ homeostasis and abnormal electrical response to beta -adrenergic stimulation. We sought to determine whether this behaviour is associated with abnormal changes of repolarization during exercise and worsening of diastolic function, ultimately explaining the intolerance to exercise experienced by some patients without obstruction. Methods and results Non-obstructive HCM patients (178) and control subjects (81) underwent standard exercise testing, including exercise echocardiography. Ventricular myocytes were isolated from myocardial samples of 23 HCM and eight non-failing non-hypertrophic surgical patients. The APD shortening in response to high frequencies was maintained in HCM myocytes, while β-adrenergic stimulation unexpectedly prolonged APDs, ultimately leading to a lesser shortening of APDs in response to exercise. In HCM vs. control subjects, we observed a lesser shortening of QT interval at peak exercise (QTc: +27 ± 52 ms in HCM, −4 ± 50 ms in controls, P < 0.0001). In patients showing a marked QTc prolongation (>30 ms), the excessive shortening of the electrical diastolic period was linked with a limited increase of heart-rate and deterioration of diastolic function at peak effort. Conclusions Abnormal balance of Ca2+- and K+-currents in HCM cardiomyocytes determines insufficient APD and Ca2+-transient shortening with exercise. In HCM patients, exercise-induced QTc prolongation was associated with impaired diastolic reserve, contributing to the reduced exercise tolerance. Our results support the idea that severe electrical cardiomyocyte abnormalities underlie exercise intolerance in a subgroup of HCM patients without obstruction.
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Affiliation(s)
- Raffaele Coppini
- Department NeuroFarBa, University of Florence , Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Matteo Beltrami
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Ruben Doste
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd , Oxford OX1 3QD, UK
| | - Alfonso Bueno-Orovio
- Department of Computer Science, University of Oxford, Wolfson Building, Parks Rd , Oxford OX1 3QD, UK
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Giulia Vitale
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Josè Manuel Pioner
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Lorenzo Santini
- Department NeuroFarBa, University of Florence , Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Alessia Argirò
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Martina Berteotti
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Fabio Mori
- Cardiothoracovascular Department, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Niccolò Marchionni
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
- Cardiothoracovascular Department, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Pierluigi Stefàno
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
- Cardiothoracovascular Department, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
| | - Elisabetta Cerbai
- Department NeuroFarBa, University of Florence , Viale G. Pieraccini 6, 50139 Florence, Italy
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
| | - Iacopo Olivotto
- Cardiomyopathy Unit, Careggi University Hospital , Largo Brambilla 3, 50134 Firenze, Italy
- Department of Experimental and Clinical Medicine, University of Florence , Largo Brambilla 3, 50134 Firenze, Italy
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19
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Pioner JM, Vitale G, Gentile F, Scellini B, Piroddi N, Cerbai E, Olivotto I, Tardiff J, Coppini R, Tesi C, Poggesi C, Ferrantini C. Genotype-Driven Pathogenesis of Atrial Fibrillation in Hypertrophic Cardiomyopathy: The Case of Different TNNT2 Mutations. Front Physiol 2022; 13:864547. [PMID: 35514357 PMCID: PMC9062294 DOI: 10.3389/fphys.2022.864547] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/28/2022] [Indexed: 11/25/2022] Open
Abstract
Atrial dilation and atrial fibrillation (AF) are common in Hypertrophic CardioMyopathy (HCM) patients and associated with a worsening of prognosis. The pathogenesis of atrial myopathy in HCM remains poorly investigated and no specific association with genotype has been identified. By re-analysis of our cohort of thin-filament HCM patients (Coppini et al. 2014) AF was identified in 10% of patients with sporadic mutations in the cardiac Troponin T gene (TNNT2), while AF occurrence was much higher (25-75%) in patients carrying specific "hot-spot" TNNT2 mutations. To determine the molecular basis of arrhythmia occurrence, two HCM mouse models expressing human TNNT2 variants (a "hot-spot" one, R92Q, and a "sporadic" one, E163R) were selected according to the different pathophysiological pathways previously demonstrated in ventricular tissue. Echocardiography studies showed a significant left atrial dilation in both models, but more pronounced in the R92Q. In E163R atrial trabeculae, in line with what previously observed in ventricular preparations, the energy cost of tension generation was markedly increased. However, no changes of twitch amplitude and kinetics were observed, and there was no atrial arrhythmic propensity. R92Q atrial trabeculae, instead, displayed normal ATP consumption but markedly increased myofilament calcium sensitivity, as previously observed in ventricular preparations. This was associated with reduced inotropic reserve and slower kinetics of twitch contractions and, importantly, with an increased occurrence of spontaneous beats and triggered contractions that represent an intrinsic arrhythmogenic mechanism promoting AF. The association of specific TNNT2 mutations with AF occurrence depends on the mutation-driven pathomechanism (i.e., increased atrial myofilament calcium sensitivity rather than increased myofilament tension cost) and may influence the individual response to treatment.
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Affiliation(s)
| | - Giulia Vitale
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Francesca Gentile
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Beatrice Scellini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Nicoletta Piroddi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | | | - Iacopo Olivotto
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Jil Tardiff
- Department of Medicine and Biomedical Engineering, University of Arizona, Tucson, AZ, United States
| | | | - Chiara Tesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
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20
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Moore J, Emili A. Mass-Spectrometry-Based Functional Proteomic and Phosphoproteomic Technologies and Their Application for Analyzing Ex Vivo and In Vitro Models of Hypertrophic Cardiomyopathy. Int J Mol Sci 2021; 22:13644. [PMID: 34948439 PMCID: PMC8709159 DOI: 10.3390/ijms222413644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 12/10/2021] [Accepted: 12/15/2021] [Indexed: 11/25/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is an autosomal dominant disease thought to be principally caused by mutations in sarcomeric proteins. Despite extensive genetic analysis, there are no comprehensive molecular frameworks for how single mutations in contractile proteins result in the diverse assortment of cellular, phenotypic, and pathobiological cascades seen in HCM. Molecular profiling and system biology approaches are powerful tools for elucidating, quantifying, and interpreting dynamic signaling pathways and differential macromolecule expression profiles for a wide range of sample types, including cardiomyopathy. Cutting-edge approaches combine high-performance analytical instrumentation (e.g., mass spectrometry) with computational methods (e.g., bioinformatics) to study the comparative activity of biochemical pathways based on relative abundances of functionally linked proteins of interest. Cardiac research is poised to benefit enormously from the application of this toolkit to cardiac tissue models, which recapitulate key aspects of pathogenesis. In this review, we evaluate state-of-the-art mass-spectrometry-based proteomic and phosphoproteomic technologies and their application to in vitro and ex vivo models of HCM for global mapping of macromolecular alterations driving disease progression, emphasizing their potential for defining the components of basic biological systems, the fundamental mechanistic basis of HCM pathogenesis, and treating the ensuing varied clinical outcomes seen among affected patient cohorts.
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Affiliation(s)
- Jarrod Moore
- Center for Network Systems Biology, Boston University School of Medicine, Boston, MA 02118, USA;
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
- MD-PhD Program, Boston University School of Medicine, Boston, MA 02118, USA
| | - Andrew Emili
- Center for Network Systems Biology, Boston University School of Medicine, Boston, MA 02118, USA;
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
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21
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Cheng Z, Fang T, Huang J, Guo Y, Alam M, Qian H. Hypertrophic Cardiomyopathy: From Phenotype and Pathogenesis to Treatment. Front Cardiovasc Med 2021; 8:722340. [PMID: 34760939 PMCID: PMC8572854 DOI: 10.3389/fcvm.2021.722340] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 09/17/2021] [Indexed: 02/05/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a very common inherited cardiovascular disease (CAD) and the incidence is about 1/500 of the common population. It is caused by more than 1,400 mutations in 11 or more genes encoding the proteins of the cardiac sarcomere. HCM presents a heterogeneous clinical profile and complex pathophysiology and HCM is the most important cause of sudden cardiac death (SCD) in young people. HCM also contributes to functional disability from heart failure and stroke (caused by atrial fibrillation). Current treatments for HCM (medication, myectomy, and alcohol septal ablation) are geared toward slowing down the disease progression and symptom relief and implanted cardiac defibrillator (ICD) to prevent SCD. HCM is, however, entering a period of tight translational research that holds promise for the major advances in disease-specific therapy. Main insights into the genetic landscape of HCM have improved our understanding of molecular pathogenesis and pointed the potential targets for the development of therapeutic agents. We reviewed the critical discoveries about the treatments, mechanism of HCM, and their implications for future research.
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Affiliation(s)
- Zeyi Cheng
- Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Tingting Fang
- Department of Cardiology, West China Hospital, Sichuan University, Chengdu, China
| | - Jinglei Huang
- School of Medicine, Lanzhou University, Lanzhou, China
| | - Yingqiang Guo
- Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu, China
| | - Mahboob Alam
- Division of Cardiovascular Medicine, Department of Medicine, Baylor College of Medicine, Houston, TX, United States
| | - Hong Qian
- Department of Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu, China
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22
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Ion Channel Impairment and Myofilament Ca 2+ Sensitization: Two Parallel Mechanisms Underlying Arrhythmogenesis in Hypertrophic Cardiomyopathy. Cells 2021; 10:cells10102789. [PMID: 34685769 PMCID: PMC8534456 DOI: 10.3390/cells10102789] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 10/07/2021] [Accepted: 10/13/2021] [Indexed: 11/17/2022] Open
Abstract
Life-threatening ventricular arrhythmias are the main clinical burden in patients with hypertrophic cardiomyopathy (HCM), and frequently occur in young patients with mild structural disease. While massive hypertrophy, fibrosis and microvascular ischemia are the main mechanisms underlying sustained reentry-based ventricular arrhythmias in advanced HCM, cardiomyocyte-based functional arrhythmogenic mechanisms are likely prevalent at earlier stages of the disease. In this review, we will describe studies conducted in human surgical samples from HCM patients, transgenic animal models and human cultured cell lines derived from induced pluripotent stem cells. Current pieces of evidence concur to attribute the increased risk of ventricular arrhythmias in early HCM to different cellular mechanisms. The increase of late sodium current and L-type calcium current is an early observation in HCM, which follows post-translation channel modifications and increases the occurrence of early and delayed afterdepolarizations. Increased myofilament Ca2+ sensitivity, commonly observed in HCM, may promote afterdepolarizations and reentry arrhythmias with direct mechanisms. Decrease of K+-currents due to transcriptional regulation occurs in the advanced disease and contributes to reducing the repolarization-reserve and increasing the early afterdepolarizations (EADs). The presented evidence supports the idea that patients with early-stage HCM should be considered and managed as subjects with an acquired channelopathy rather than with a structural cardiac disease.
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23
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Tjahjadi C, Hiemstra YL, van der Bijl P, Pio SM, Bootsma M, Ajmone Marsan N, Delgado V, Bax JJ. Assessment of left atrial electro-mechanical delay to predict atrial fibrillation in hypertrophic cardiomyopathy. Eur Heart J Cardiovasc Imaging 2021; 22:589-596. [PMID: 32588037 DOI: 10.1093/ehjci/jeaa174] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 05/07/2020] [Accepted: 05/29/2020] [Indexed: 01/09/2023] Open
Abstract
AIMS Atrial fibrillation (AF) is frequently observed in hypertrophic cardiomyopathy (HCM) and is associated with poor clinical outcome. Total atrial conduction time, estimated by tissue Doppler imaging (TDI), the so-called PA-TDI duration, reflects the left atrial (LA) structural and electrical remodelling. The aim of this study was to evaluate the association between PA-TDI and new-onset AF in patients with HCM. METHODS AND RESULTS From a large cohort of patients with HCM, 208 patients (64% male, mean age 53 ± 14 years) without AF were selected. PA-TDI duration was measured from the onset P wave on electrocardiogram to the peak A' wave of the lateral LA wall using TDI. The incidence of new-onset AF was 20% over a median follow-up of 7.3 (3.5-10.5) years. Patients with incident AF had longer PA-TDI duration when compared with patients without AF (133.7 ± 23.0 vs. 110.5 ± 30.0 ms, P < 0.001). PA-TDI duration was independently associated with new-onset AF (hazard ratio: 1.03, 95% confidence interval: 1.01-1.05, P < 0.001). CONCLUSION Prolonged PA-TDI duration was independently associated with new-onset AF in patients with HCM. This novel parameter could be useful to risk-stratify patients with HCM who are at risk of having AF.
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Affiliation(s)
- Catherina Tjahjadi
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Yasmine L Hiemstra
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Pieter van der Bijl
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Stephan M Pio
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Marianne Bootsma
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Nina Ajmone Marsan
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Victoria Delgado
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
| | - Jeroen J Bax
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 RC Leiden, The Netherlands
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24
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Sewanan LR, Park J, Rynkiewicz MJ, Racca AW, Papoutsidakis N, Schwan J, Jacoby DL, Moore JR, Lehman W, Qyang Y, Campbell SG. Loss of crossbridge inhibition drives pathological cardiac hypertrophy in patients harboring the TPM1 E192K mutation. J Gen Physiol 2021; 153:212516. [PMID: 34319370 PMCID: PMC8321830 DOI: 10.1085/jgp.202012640] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 06/14/2021] [Accepted: 07/09/2021] [Indexed: 01/10/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is an inherited disorder caused primarily by mutations to thick and thinfilament proteins. Although thin filament mutations are less prevalent than their oft-studied thick filament counterparts, they are frequently associated with severe patient phenotypes and can offer important insight into fundamental disease mechanisms. We have performed a detailed study of tropomyosin (TPM1) E192K, a variant of uncertain significance associated with HCM. Molecular dynamics revealed that E192K results in a more flexible TPM1 molecule, which could affect its ability to regulate crossbridges. In vitro motility assays of regulated actin filaments containing TPM1 E192K showed an overall loss of Ca2+ sensitivity. To understand these effects, we used multiscale computational models that suggested a subtle phenotype in which E192K leads to an inability to completely inhibit actin-myosin crossbridge activity at low Ca2+. To assess the physiological impact of the mutation, we generated patient-derived engineered heart tissues expressing E192K. These tissues showed disease features similar to those of the patients, including cellular hypertrophy, hypercontractility, and diastolic dysfunction. We hypothesized that excess residual crossbridge activity could be triggering cellular hypertrophy, even if the overall Ca2+ sensitivity was reduced by E192K. To test this hypothesis, the cardiac myosin-specific inhibitor mavacamten was applied to patient-derived engineered heart tissues for 4 d followed by 24 h of washout. Chronic mavacamten treatment abolished contractile differences between control and TPM1 E192K engineered heart tissues and reversed hypertrophy in cardiomyocytes. These results suggest that the TPM1 E192K mutation triggers cardiomyocyte hypertrophy by permitting excess residual crossbridge activity. These studies also provide direct evidence that myosin inhibition by mavacamten can counteract the hypertrophic effects of mutant tropomyosin.
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Affiliation(s)
- Lorenzo R Sewanan
- Department of Biomedical Engineering, Yale University, New Haven, CT
| | - Jinkyu Park
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale Cardiovascular Research Center, Yale School of Medicine, New Haven, CT.,Yale Stem Cell Center, Yale School of Medicine, New Haven, CT
| | - Michael J Rynkiewicz
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA
| | - Alice W Racca
- Department of Biological Sciences, University of Massachusetts, Lowell, MA
| | - Nikolaos Papoutsidakis
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, CT
| | - Jonas Schwan
- Department of Biomedical Engineering, Yale University, New Haven, CT
| | - Daniel L Jacoby
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, CT
| | - Jeffrey R Moore
- Department of Biological Sciences, University of Massachusetts, Lowell, MA
| | - William Lehman
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA
| | - Yibing Qyang
- Department of Internal Medicine, Section of Cardiovascular Medicine, Yale Cardiovascular Research Center, Yale School of Medicine, New Haven, CT.,Yale Stem Cell Center, Yale School of Medicine, New Haven, CT.,Vascular Biology and Therapeutics Program, Yale University, New Haven, CT.,Department of Pathology, Yale University, New Haven, CT
| | - Stuart G Campbell
- Department of Biomedical Engineering, Yale University, New Haven, CT.,Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, CT
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25
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Sewanan LR, Jacoby DL. Novel Myosin-Based Therapies in Hypertrophic Cardiomyopathy. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2021. [DOI: 10.1007/s11936-021-00921-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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26
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Scellini B, Piroddi N, Dente M, Vitale G, Pioner JM, Coppini R, Ferrantini C, Poggesi C, Tesi C. Mavacamten has a differential impact on force generation in myofibrils from rabbit psoas and human cardiac muscle. J Gen Physiol 2021; 153:212024. [PMID: 33891673 PMCID: PMC8077167 DOI: 10.1085/jgp.202012789] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/04/2021] [Accepted: 03/30/2021] [Indexed: 12/20/2022] Open
Abstract
Mavacamten (MYK-461) is a small-molecule allosteric inhibitor of sarcomeric myosins being used in preclinical/clinical trials for hypertrophic cardiomyopathy treatment. A better understanding of its impact on force generation in intact or skinned striated muscle preparations, especially for human cardiac muscle, has been hindered by diffusional barriers. These limitations have been overcome by mechanical experiments using myofibrils subject to perturbations of the contractile environment by sudden solution changes. Here, we characterize the action of mavacamten in human ventricular myofibrils compared with fast skeletal myofibrils from rabbit psoas. Mavacamten had a fast, fully reversible, and dose-dependent negative effect on maximal Ca2+-activated isometric force at 15°C, which can be explained by a sudden decrease in the number of heads functionally available for interaction with actin. It also decreased the kinetics of force development in fast skeletal myofibrils, while it had no effect in human ventricular myofibrils. For both myofibril types, the effects of mavacamten were independent from phosphate in the low-concentration range. Mavacamten did not alter force relaxation of fast skeletal myofibrils, but it significantly accelerated the relaxation of human ventricular myofibrils. Lastly, mavacamten had no effect on resting tension but inhibited the ADP-stimulated force in the absence of Ca2+. Altogether, these effects outline a motor isoform-specific dependence of the inhibitory effect of mavacamten on force generation, which is mediated by a reduction in the availability of strongly actin-binding heads. Mavacamten may thus alter the interplay between thick and thin filament regulation mechanisms of contraction in association with the widely documented drug effect of stabilizing myosin motor heads into autoinhibited states.
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Affiliation(s)
- Beatrice Scellini
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Nicoletta Piroddi
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Marica Dente
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Giulia Vitale
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Josè Manuel Pioner
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Raffaele Coppini
- Department of Neuroscience, Psychology, Drug Sciences, and Child Health, University of Florence, Florence, Italy
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
| | - Chiara Tesi
- Department of Experimental and Clinical Medicine, Division of Physiology, University of Florence, Florence, Italy
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27
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Clippinger SR, Cloonan PE, Wang W, Greenberg L, Stump WT, Angsutararux P, Nerbonne JM, Greenberg MJ. Mechanical dysfunction of the sarcomere induced by a pathogenic mutation in troponin T drives cellular adaptation. J Gen Physiol 2021; 153:211992. [PMID: 33856419 PMCID: PMC8054178 DOI: 10.1085/jgp.202012787] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 03/18/2021] [Indexed: 12/15/2022] Open
Abstract
Familial hypertrophic cardiomyopathy (HCM), a leading cause of sudden cardiac death, is primarily caused by mutations in sarcomeric proteins. The pathogenesis of HCM is complex, with functional changes that span scales, from molecules to tissues. This makes it challenging to deconvolve the biophysical molecular defect that drives the disease pathogenesis from downstream changes in cellular function. In this study, we examine an HCM mutation in troponin T, R92Q, for which several models explaining its effects in disease have been put forward. We demonstrate that the primary molecular insult driving disease pathogenesis is mutation-induced alterations in tropomyosin positioning, which causes increased molecular and cellular force generation during calcium-based activation. Computational modeling shows that the increased cellular force is consistent with the molecular mechanism. These changes in cellular contractility cause downstream alterations in gene expression, calcium handling, and electrophysiology. Taken together, our results demonstrate that molecularly driven changes in mechanical tension drive the early disease pathogenesis of familial HCM, leading to activation of adaptive mechanobiological signaling pathways.
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Affiliation(s)
- Sarah R Clippinger
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - Paige E Cloonan
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - Wei Wang
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Lina Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - W Tom Stump
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | | | - Jeanne M Nerbonne
- Cardiovascular Division, Department of Medicine, Washington University School of Medicine, St. Louis, MO
| | - Michael J Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
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28
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T-tubule remodeling in human hypertrophic cardiomyopathy. J Muscle Res Cell Motil 2020; 42:305-322. [PMID: 33222034 PMCID: PMC8332592 DOI: 10.1007/s10974-020-09591-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 10/22/2020] [Indexed: 11/17/2022]
Abstract
The highly organized transverse T-tubule membrane system represents the ultrastructural substrate for excitation–contraction coupling in ventricular myocytes. While the architecture and function of T-tubules have been well described in animal models, there is limited morpho-functional data on T-tubules in human myocardium. Hypertrophic cardiomyopathy (HCM) is a primary disease of the heart muscle, characterized by different clinical presentations at the various stages of its progression. Most HCM patients, indeed, show a compensated hypertrophic disease (“non-failing hypertrophic phase”), with preserved left ventricular function, and only a small subset of individuals evolves into heart failure (“end stage HCM”). In terms of T-tubule remodeling, the “end-stage” disease does not differ from other forms of heart failure. In this review we aim to recapitulate the main structural features of T-tubules during the “non-failing hypertrophic stage” of human HCM by revisiting data obtained from human myectomy samples. Moreover, by comparing pathological changes observed in myectomy samples with those introduced by acute (experimentally induced) detubulation, we discuss the role of T-tubular disruption as a part of the complex excitation–contraction coupling remodeling process that occurs during disease progression. Lastly, we highlight how T-tubule morpho-functional changes may be related to patient genotype and we discuss the possibility of a primitive remodeling of the T-tubule system in rare HCM forms associated with genes coding for proteins implicated in T-tubule structural integrity, formation and maintenance.
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29
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Vikhorev PG, Vikhoreva NN, Yeung W, Li A, Lal S, dos Remedios CG, Blair CA, Guglin M, Campbell KS, Yacoub MH, de Tombe P, Marston SB. Titin-truncating mutations associated with dilated cardiomyopathy alter length-dependent activation and its modulation via phosphorylation. Cardiovasc Res 2020; 118:241-253. [PMID: 33135063 PMCID: PMC8752363 DOI: 10.1093/cvr/cvaa316] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 10/20/2020] [Indexed: 12/18/2022] Open
Abstract
Abstract
Aims
Dilated cardiomyopathy (DCM) is associated with mutations in many genes encoding sarcomere proteins. Truncating mutations in the titin gene TTN are the most frequent. Proteomic and functional characterizations are required to elucidate the origin of the disease and the pathogenic mechanisms of TTN-truncating variants.
Methods and results
We isolated myofibrils from DCM hearts carrying truncating TTN mutations and measured the Ca2+ sensitivity of force and its length dependence. Simultaneous measurement of force and adenosine triphosphate (ATP) consumption in skinned cardiomyocytes was also performed. Phosphorylation levels of troponin I (TnI) and myosin binding protein-C (MyBP-C) were manipulated using protein kinase A and λ phosphatase. mRNA sequencing was employed to overview gene expression profiles. We found that Ca2+ sensitivity of myofibrils carrying TTN mutations was significantly higher than in myofibrils from donor hearts. The length dependence of the Ca2+ sensitivity was absent in DCM myofibrils with TTN-truncating variants. No significant difference was found in the expression level of TTN mRNA between the DCM and donor groups. TTN exon usage and splicing were also similar. However, we identified down-regulation of genes encoding Z-disk proteins, while the atrial-specific regulatory myosin light chain gene, MYL7, was up-regulated in DCM patients with TTN-truncating variants.
Conclusion
Titin-truncating mutations lead to decreased length-dependent activation and increased elasticity of myofibrils. Phosphorylation levels of TnI and MyBP-C seen in the left ventricles are essential for the length-dependent changes in Ca2+ sensitivity in healthy donors, but they are reduced in DCM patients with TTN-truncating variants. A decrease in expression of Z-disk proteins may explain the observed decrease in myofibril passive stiffness and length-dependent activation.
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Affiliation(s)
- Petr G Vikhorev
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Natalia N Vikhoreva
- Heart Science Centre, Magdi Yacoub Institute, Harefield Hospital, London UB9 6JH, UK
| | - WaiChun Yeung
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Amy Li
- Department of Pharmacy and Biomedical Sciences, La Trobe University, Bendigo, VIC 3550, Australia
| | - Sean Lal
- School of Medical Sciences, Faculty of Medicine and Health, University of Sydney, NSW 2006, Australia
| | - Cristobal G dos Remedios
- Division of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia
| | - Cheavar A Blair
- Division of Cardiovascular Medicine, Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Maya Guglin
- Division of Cardiovascular Medicine, Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Kenneth S Campbell
- Division of Cardiovascular Medicine, Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Magdi H Yacoub
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London W12 0NN, UK
| | - Pieter de Tombe
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London W12 0NN, UK
- Heart Science Centre, Magdi Yacoub Institute, Harefield Hospital, London UB9 6JH, UK
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, IL, USA
| | - Steven B Marston
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London W12 0NN, UK
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30
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Santini L, Palandri C, Nediani C, Cerbai E, Coppini R. Modelling genetic diseases for drug development: Hypertrophic cardiomyopathy. Pharmacol Res 2020; 160:105176. [DOI: 10.1016/j.phrs.2020.105176] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/16/2020] [Accepted: 08/22/2020] [Indexed: 12/13/2022]
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31
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Solomon T, Filipovska A, Hool L, Viola H. Preventative therapeutic approaches for hypertrophic cardiomyopathy. J Physiol 2020; 599:3495-3512. [PMID: 32822065 PMCID: PMC8359240 DOI: 10.1113/jp279410] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 08/06/2020] [Indexed: 11/08/2022] Open
Abstract
Sarcomeric gene mutations are associated with the development of hypertrophic cardiomyopathy (HCM). Current drug therapeutics for HCM patients are effective in relieving symptoms, but do not prevent or reverse disease progression. Moreover, due to heterogeneity in the clinical manifestations of the disease, patients experience variable outcomes in response to therapeutics. Mechanistically, alterations in calcium handling, sarcomeric disorganization, energy metabolism and contractility participate in HCM disease progression. While some similarities exist, each mutation appears to lead to mutation‐specific pathophysiology. Furthermore, these alterations may precede or proceed development of the pathology. This review assesses the efficacy of HCM therapeutics from studies performed in animal models of HCM and human clinical trials. Evidence suggests that a preventative rather than corrective therapeutic approach may be more efficacious in the treatment of HCM. In addition, a clear understanding of mutation‐specific mechanisms may assist in informing the most effective therapeutic mode of action.
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Affiliation(s)
- Tanya Solomon
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Aleksandra Filipovska
- Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, Australia.,ARC Centre of Excellence in Synthetic Biology, QEII Medical Centre, Nedlands, Western Australia, Australia.,Centre for Medical Research, University of Western Australia, QEII Medical Centre, Nedlands, Western Australia, Australia.,Telethon Kids Institute, Perth Children's Hospital, Nedlands, Western Australia, Australia.,School of Molecular Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Livia Hool
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia.,Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
| | - Helena Viola
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia
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Parbhudayal RY, Harms HJ, Michels M, van Rossum AC, Germans T, van der Velden J. Increased Myocardial Oxygen Consumption Precedes Contractile Dysfunction in Hypertrophic Cardiomyopathy Caused by Pathogenic TNNT2 Gene Variants. J Am Heart Assoc 2020; 9:e015316. [PMID: 32290750 PMCID: PMC7428531 DOI: 10.1161/jaha.119.015316] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Background Hypertrophic cardiomyopathy is caused by pathogenic sarcomere gene variants. Individuals with a thin‐filament variant present with milder hypertrophy than carriers of thick‐filament variants, although prognosis is poorer. Herein, we defined if decreased energetic status of the heart is an early pathomechanism in TNNT2 (troponin T gene) variant carriers. Methods and Results Fourteen individuals with TNNT2 variants (genotype positive), without left ventricular hypertrophy (G+/LVH−; n=6) and with LVH (G+/LVH+; n=8) and 14 healthy controls were included. All participants underwent cardiac magnetic resonance and [11C]‐acetate positron emission tomography imaging to assess LV myocardial oxygen consumption, contractile parameters and myocardial external efficiency. Cardiac efficiency was significantly reduced compared with controls in G+/LVH− and G+/LVH+. Lower myocardial external efficiency in G+/LVH− is explained by higher global and regional oxygen consumption compared with controls without changes in contractile parameters. Reduced myocardial external efficiency in G+/LVH+ is explained by the increase in LV mass and higher oxygen consumption. Septal oxygen consumption was significantly lower in G+/LVH+ compared with G+/LVH−. Although LV ejection fraction was higher in G+/LVH+, both systolic and diastolic strain parameters were lower compared with controls, which was most evident in the hypertrophied septal wall. Conclusions Using cardiac magnetic resonance and [11C]‐acetate positron emission tomography imaging, we show that G+/LVH− have an initial increase in oxygen consumption preceding contractile dysfunction and cardiac hypertrophy, followed by a decline in oxygen consumption in G+/LVH+. This suggests that high oxygen consumption and reduced myocardial external efficiency characterize the early gene variant–mediated disease mechanisms that may be used for early diagnosis and development of preventive treatments.
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Affiliation(s)
- Rahana Y Parbhudayal
- Department of Cardiology Amsterdam University Medical Center Amsterdam Cardiovascular Sciences Vrije Universiteit University Medical Center Amsterdam Amsterdam the Netherlands.,Department of Physiology Amsterdam University Medical Center Amsterdam Cardiovascular Sciences Vrije Universiteit University Medical Center Amsterdam Amsterdam the Netherlands.,The Netherlands Heart Institute Utrecht the Netherlands
| | - Hendrik J Harms
- Department of Nuclear Medicine and PET Center Aarhus University Aarhus Denmark
| | - Michelle Michels
- Department of Cardiology Erasmus Medical Center Rotterdam the Netherlands
| | - Albert C van Rossum
- Department of Cardiology Amsterdam University Medical Center Amsterdam Cardiovascular Sciences Vrije Universiteit University Medical Center Amsterdam Amsterdam the Netherlands
| | - Tjeerd Germans
- Department of Cardiology Amsterdam University Medical Center Amsterdam Cardiovascular Sciences Vrije Universiteit University Medical Center Amsterdam Amsterdam the Netherlands
| | - Jolanda van der Velden
- Department of Physiology Amsterdam University Medical Center Amsterdam Cardiovascular Sciences Vrije Universiteit University Medical Center Amsterdam Amsterdam the Netherlands.,The Netherlands Heart Institute Utrecht the Netherlands
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33
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Cimiotti D, Fujita-Becker S, Möhner D, Smolina N, Budde H, Wies A, Morgenstern L, Gudkova A, Sejersen T, Sjöberg G, Mügge A, Nowaczyk MM, Reusch P, Pfitzer G, Stehle R, Schröder RR, Mannherz HG, Kostareva A, Jaquet K. Infantile restrictive cardiomyopathy: cTnI-R170G/W impair the interplay of sarcomeric proteins and the integrity of thin filaments. PLoS One 2020; 15:e0229227. [PMID: 32182250 PMCID: PMC7077804 DOI: 10.1371/journal.pone.0229227] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 01/31/2020] [Indexed: 12/11/2022] Open
Abstract
TNNI3 encoding cTnI, the inhibitory subunit of the troponin complex, is the main target for mutations leading to restrictive cardiomyopathy (RCM). Here we investigate two cTnI-R170G/W amino acid replacements, identified in infantile RCM patients, which are located in the regulatory C-terminus of cTnI. The C-terminus is thought to modulate the function of the inhibitory region of cTnI. Both cTnI-R170G/W strongly enhanced the Ca2+-sensitivity of skinned fibres, as is typical for RCM-mutations. Both mutants strongly enhanced the affinity of troponin (cTn) to tropomyosin compared to wildtype cTn, whereas binding to actin was either strengthened (R170G) or weakened (R170W). Furthermore, the stability of reconstituted thin filaments was reduced as revealed by electron microscopy. Filaments containing R170G/W appeared wavy and showed breaks. Decoration of filaments with myosin subfragment S1 was normal in the presence of R170W, but was irregular with R170G. Surprisingly, both mutants did not affect the Ca2+-dependent activation of reconstituted cardiac thin filaments. In the presence of the N-terminal fragment of cardiac myosin binding protein C (cMyBPC-C0C2) cooperativity of thin filament activation was increased only when the filaments contained wildtype cTn. No effect was observed in the presence of cTn containing R170G/W. cMyBPC-C0C2 significantly reduced binding of wildtype troponin to actin/tropomyosin, but not of both mutant cTn. Moreover, we found a direct troponin/cMyBPC-C0C2 interaction using microscale thermophoresis and identified cTnI and cTnT, but not cTnC as binding partners for cMyBPC-C0C2. Only cTn containing cTnI-R170G showed a reduced affinity towards cMyBPC-C0C2. Our results suggest that the RCM cTnI variants R170G/W impair the communication between thin and thick filament proteins and destabilize thin filaments.
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Affiliation(s)
- Diana Cimiotti
- Department of Clinical Pharmacology and Molecular Cardiology, Ruhr-University of Bochum, Bochum, Germany.,Cardiology, Bergmannsheil and St. Josef Hospital, Clinics of the Ruhr-University Bochum, Bochum, Germany
| | - Setsuko Fujita-Becker
- Cryoelectron Microscopy, BioQuant, Medical Faculty, University of Heidelberg, Heidelberg, Germany
| | - Desirée Möhner
- Vegetative Physiology, University of Cologne, Cologne, Germany
| | - Natalia Smolina
- Department of Molecular Biology and Genetics, Almazov Federal Medical Research Center, St. Petersburg, Russia
| | - Heidi Budde
- Department of Clinical Pharmacology and Molecular Cardiology, Ruhr-University of Bochum, Bochum, Germany.,Cardiology, Bergmannsheil and St. Josef Hospital, Clinics of the Ruhr-University Bochum, Bochum, Germany
| | - Aline Wies
- Vegetative Physiology, University of Cologne, Cologne, Germany
| | - Lisa Morgenstern
- Department of Clinical Pharmacology and Molecular Cardiology, Ruhr-University of Bochum, Bochum, Germany.,Cardiology, Bergmannsheil and St. Josef Hospital, Clinics of the Ruhr-University Bochum, Bochum, Germany
| | - Alexandra Gudkova
- Department of Molecular Biology and Genetics, Almazov Federal Medical Research Center, St. Petersburg, Russia
| | - Thomas Sejersen
- Department of Women's and Children's Health and Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden
| | - Gunnar Sjöberg
- Department of Women's and Children's Health and Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden
| | - Andreas Mügge
- Cardiology, Bergmannsheil and St. Josef Hospital, Clinics of the Ruhr-University Bochum, Bochum, Germany
| | - Marc M Nowaczyk
- Plant Biochemistry, Faculty of Biology and Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Peter Reusch
- Department of Clinical Pharmacology and Molecular Cardiology, Ruhr-University of Bochum, Bochum, Germany
| | | | - Robert Stehle
- Vegetative Physiology, University of Cologne, Cologne, Germany
| | - Rasmus R Schröder
- Cryoelectron Microscopy, BioQuant, Medical Faculty, University of Heidelberg, Heidelberg, Germany
| | - Hans G Mannherz
- Department of Clinical Pharmacology and Molecular Cardiology, Ruhr-University of Bochum, Bochum, Germany.,Department of Anatomy and Embryology, Medical Faculty, Ruhr-University Bochum, Bochum, Germany
| | - Anna Kostareva
- Department of Molecular Biology and Genetics, Almazov Federal Medical Research Center, St. Petersburg, Russia.,Department of Women's and Children's Health and Center for Molecular Medicine, Karolinska Institute, Stockholm, Sweden
| | - Kornelia Jaquet
- Department of Clinical Pharmacology and Molecular Cardiology, Ruhr-University of Bochum, Bochum, Germany.,Cardiology, Bergmannsheil and St. Josef Hospital, Clinics of the Ruhr-University Bochum, Bochum, Germany
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34
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Chowdhury SAK, Warren CM, Simon JN, Ryba DM, Batra A, Varga P, Kranias EG, Tardiff JC, Solaro RJ, Wolska BM. Modifications of Sarcoplasmic Reticulum Function Prevent Progression of Sarcomere-Linked Hypertrophic Cardiomyopathy Despite a Persistent Increase in Myofilament Calcium Response. Front Physiol 2020; 11:107. [PMID: 32210830 PMCID: PMC7075858 DOI: 10.3389/fphys.2020.00107] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 01/30/2020] [Indexed: 01/12/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a genetic disorder caused by mutations in different genes mainly encoding myofilament proteins and therefore called a “disease of the sarcomere.” Despite the discovery of sarcomere protein mutations linked to HCM almost 30 years ago, the cellular mechanisms responsible for the development of this disease are not completely understood and likely vary among different mutations. Moreover, despite many efforts to develop effective treatments for HCM, these have largely been unsuccessful, and more studies are needed to better understand the cellular mechanisms of the disease. In experiments reported here, we investigated a mouse model expressing the mutant cTnT-R92Q, which is linked to HCM and induces an increase in myofilament Ca2+ sensitivity and diastolic dysfunction. We found that early correction of the diastolic dysfunction by phospholamban knockout (PLNKO) was able to prevent the development of the HCM phenotype in troponin T (TnT)-R92Q transgenic (TG) mice. Four groups of mice in FVB/N background were generated and used for the experiments: (1) non-transgenic (NTG)/PLN mice, which express wild-type TnT and normal level of PLN; (2) NTG/PLNKO mice, which express wild-type TnT and no PLN; (3) TG/PLN mice, which express TnT-R92Q and normal level of PLN; (4) TG/PLNKO mice, which express TnT-R92Q and no PLN. Cardiac function was determined using both standard echocardiographic parameters and speckle tracking strain measurements. We found that both atrial morphology and diastolic function were altered in TG/PLN mice but normal in TG/PLNKO mice. Histological analysis showed a disarray of myocytes and increased collagen deposition only in TG/PLN hearts. We also observed increased Ca2+/calmodulin-dependent protein kinase II (CaMKII) phosphorylation only in TG/PLN hearts but not in TG/PLNKO hearts. The rescue of the HCM phenotype was not associated with differences in myofilament Ca2+ sensitivity between TG/PLN and TG/PLNKO mice. Moreover, compared to standard systolic echo parameters, such as ejection fraction (EF), speckle strain measurements provided a more sensitive approach to detect early systolic dysfunction in TG/PLN mice. In summary, our results indicate that targeting diastolic dysfunction through altering Ca2+ fluxes with no change in myofilament response to Ca2+ was able to prevent the development of the HCM phenotype and should be considered as a potential additional treatment for HCM patients.
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Affiliation(s)
- Shamim A K Chowdhury
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Chad M Warren
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Jillian N Simon
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - David M Ryba
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Ashley Batra
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Peter Varga
- Department of Pediatrics, Section of Cardiology, University of Illinois at Chicago, Chicago, IL, United States
| | - Evangelia G Kranias
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
| | - Jil C Tardiff
- Department of Medicine, Division of Cardiology, The University of Arizona, Tucson, AZ, United States
| | - R John Solaro
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Beata M Wolska
- Department of Physiology and Biophysics and the Center for Cardiovascular Research, College of Medicine, University of Illinois at Chicago, Chicago, IL, United States.,Department of Medicine, Division of Cardiology, University of Illinois at Chicago, Chicago, IL, United States
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35
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Abstract
Hypertrophic cardiomyopathy (HCM) is the most common cardiovascular disease with genetic transmission, characterized by the hypertrophy of any segment of the left ventricle (LV), not totally explained by improper loading conditions, with LV systolic function preserved, increased, or reduced. The histopathological mechanism involved in HCM refers to the primary injury of the myocardium, as follows: disorganized array of myocytes, extracellular matrix modification, microvascular dysfunction, with subsequent appearance of myocardial fibrosis. Multiple sarcomere proteins mutations are responsible for HCM, but two of them are involved in 70% of the cases of HCM: β-myosin heavy chain (MYH7) and myosin-binding protein C (MYBPC3). The development of new genetic techniques involving genome editing is promising to discover a gene therapy for patients with HCM. Clinical presentation may differ from asymptomatic to sudden cardiac death (SCD), the last one targeting younger adults. In this case, the diagnosis and evaluation of SCD risk factors is extremely important. The common method of diagnosis is transthoracic echocardiography, but cardiac magnetic resonance (CMR) imaging represents "gold standard" in the evaluation of HCM patients. Treatment includes pharmacological therapy, surgery, alcohol ablation, and not least SCD prevention.
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Affiliation(s)
- Ioana Danuta Muresan
- 2nd Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 2-4 Clinicilor, 400006, Cluj-Napoca, Romania
| | - Lucia Agoston-Coldea
- 2nd Department of Internal Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 2-4 Clinicilor, 400006, Cluj-Napoca, Romania.
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36
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The relation between sarcomere energetics and the rate of isometric tension relaxation in healthy and diseased cardiac muscle. J Muscle Res Cell Motil 2019; 42:47-57. [PMID: 31745760 PMCID: PMC7932984 DOI: 10.1007/s10974-019-09566-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 11/13/2019] [Indexed: 12/24/2022]
Abstract
Full muscle relaxation happens when [Ca2+] falls below the threshold for force activation. Several experimental models, from whole muscle organs and intact muscle down to skinned fibers, have been used to explore the cascade of kinetic events leading to mechanical relaxation. The use of single myofibrils together with fast solution switching techniques, has provided new information about the role of cross-bridge (CB) dissociation in the time course of isometric force decay. Myofibril’s relaxation is biphasic starting with a slow seemingly linear phase, with a rate constant, slow kREL, followed by a fast mono-exponential phase. Sarcomeres remain isometric during the slow force decay that reflects CB detachment under isometric conditions while the final fast relaxation phase begins with a sudden give of few sarcomeres and is then dominated by intersarcomere dynamics. Based on a simple two-state model of the CB cycle, myofibril slow kREL represents the apparent forward rate with which CBs leave force generating states (gapp) under isometric conditions and correlates with the energy cost of tension generation (ATPase/tension ratio); in short slow kREL ~ gapp ~ tension cost. The validation of this relationship is obtained by simultaneously measuring maximal isometric force and ATP consumption in skinned myocardial strips that provide an unambiguous determination of the relation between contractile and energetic properties of the sarcomere. Thus, combining kinetic experiments in isolated myofibrils and mechanical and energetic measurements in multicellular cardiac strips, we are able to provide direct evidence for a positive linear correlation between myofibril isometric relaxation kinetics (slow kREL) and the energy cost of force production both measured in preparations from the same cardiac sample. This correlation remains true among different types of muscles with different ATPase activities and also when CB kinetics are altered by cardiomyopathy-related mutations. Sarcomeric mutations associated to hypertrophic cardiomyopathy (HCM), a primary cardiac disorder caused by mutations in genes encoding sarcomeric proteins, have been often found to accelerate CB turnover rate and increase the energy cost of myocardial contraction. Here we review data showing that faster CB detachment results in a proportional increase in the energetic cost of tension generation in heart samples from both HCM patients and mouse models of the disease.
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37
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Coppini R, Ferrantini C, Pioner JM, Santini L, Wang ZJ, Palandri C, Scardigli M, Vitale G, Sacconi L, Stefàno P, Flink L, Riedy K, Pavone FS, Cerbai E, Poggesi C, Mugelli A, Bueno-Orovio A, Olivotto I, Sherrid MV. Electrophysiological and Contractile Effects of Disopyramide in Patients With Obstructive Hypertrophic Cardiomyopathy: A Translational Study. JACC Basic Transl Sci 2019; 4:795-813. [PMID: 31998849 PMCID: PMC6978554 DOI: 10.1016/j.jacbts.2019.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 06/07/2019] [Accepted: 06/07/2019] [Indexed: 01/26/2023]
Abstract
In patients with HCM and symptomatic LVOT-obstruction, first treatment with disopyramide leads to a marked reduction of LVOT gradients, with a slight decrease of resting ejection fraction and a modest increase of corrected QT interval, highlighting high efficacy and safety. In single cardiomyocytes and intact trabeculae from surgical samples of patients with obstructive HCM, in vitro treatment with 5 μmol/l disopyramide lowered force and Ca2+ transients while reducing action potential duration and the rate of arrhythmic afterdepolarizations. These effects are mediated by the combined inhibition of peak and late Na+ currents, L-type Ca2+ current, delayed-rectifier K+ current, and ryanodine receptors. In addition to the negative inotropic effect of disopyramide, in vitro results suggest additional antiarrhythmic actions.
Disopyramide is effective and safe in patients with obstructive hypertrophic cardiomyopathy. However, its cellular and molecular mechanisms of action are unknown. We tested disopyramide in cardiomyocytes from the septum of surgical myectomy patients: disopyramide inhibits multiple ion channels, leading to lower Ca transients and force, and shortens action potentials, thus reducing cellular arrhythmias. The electrophysiological profile of disopyramide explains the efficient reduction of outflow gradients but also the limited prolongation of the QT interval and the absence of arrhythmic side effects observed in 39 disopyramide-treated patients. In conclusion, our results support the idea that disopyramide is safe for outpatient use in obstructive patients.
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Key Words
- AP, action potential
- DAD, delayed afterdepolarization
- EAD, early afterdepolarization
- ECG, electrocardiography
- HCM, hypertrophic cardiomyopathy
- ICa-L, L-type Ca current
- IK, delayed-rectifier K current
- INaL, late Na current
- LVOT, left ventricular outflow tract
- NCX, Na+/Ca2+ exchanger
- QT interval
- RyR, ryanodine receptor
- SR, sarcoplasmic reticulum
- action potentials
- arrhythmias
- diastolic dysfunction
- hERG, human ether-à-go-go-related gene
- hypertrophic cardiomyopathy
- pCa, Ca activation level
- safety
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Affiliation(s)
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.,Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Josè Manuel Pioner
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Lorenzo Santini
- Department NeuroFarBa, University of Florence, Florence, Italy
| | - Zhinuo J Wang
- Department of Computer Sciences, University of Oxford, Oxford, United Kingdom
| | - Chiara Palandri
- Department NeuroFarBa, University of Florence, Florence, Italy
| | - Marina Scardigli
- European Laboratory for Nonlinear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy and National Institute of Optics, National Research Council, Florence, Italy
| | - Giulia Vitale
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Leonardo Sacconi
- European Laboratory for Nonlinear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy and National Institute of Optics, National Research Council, Florence, Italy
| | - Pierluigi Stefàno
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.,Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Laura Flink
- Division of Cardiology, San Francisco Veterans Affairs Medical Center and University of California-San Francisco, San Francisco, California
| | - Katherine Riedy
- Hypertrophic Cardiomyopathy Program, New York University Langone Health, New York, New York
| | - Francesco Saverio Pavone
- European Laboratory for Nonlinear Spectroscopy (LENS), University of Florence, Sesto Fiorentino, Italy and National Institute of Optics, National Research Council, Florence, Italy
| | | | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | | | | | - Iacopo Olivotto
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.,Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy
| | - Mark V Sherrid
- Hypertrophic Cardiomyopathy Program, New York University Langone Health, New York, New York
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38
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Lin YH, Yap J, Ramachandra CJ, Hausenloy DJ. New insights provided by myofibril mechanics in inherited cardiomyopathies. CONDITIONING MEDICINE 2019; 2:213-224. [PMID: 32133438 PMCID: PMC7055865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Cardiomyopathies represent a heterogeneous group of cardiac disorders that perturb cardiac contraction and/or relaxation, and can result in arrhythmias, heart failure, and sudden cardiac death. Based on morphological and functional differences, cardiomyopathies have been classified into hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and restrictive cardiomyopathy (RCM). It has been well documented that mutations in genes encoding sarcomeric proteins are associated with the onset of inherited cardiomyopathies. However, correlating patient genotype to the clinical phenotype has been challenging because of the complex genetic backgrounds, environmental influences, and lifestyles of individuals. Thus, "scaling down" the focus to the basic contractile unit of heart muscle using isolated single myofibril function techniques is of great importance and may be used to understand the molecular basis of disease-causing sarcomeric mutations. Single myofibril bundles harvested from diseased human or experimental animal hearts, as well as cultured adult cardiomyocytes or human cardiomyocytes derived from induced pluripotent stem cells, can be used, thereby providing an ideal multi-level, cross-species platform to dissect sarcomeric function in cardiomyopathies. Here, we will review the myofibril function technique, and discuss alterations in myofibril mechanics, which are known to occur in sarcomeric genetic mutations linked to inherited HCM, DCM, and RCM, and describe the therapeutic potential for future target identification.
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Affiliation(s)
- Ying-Hsi Lin
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore
- Cardiovascular & Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore
| | - Jonathan Yap
- Center for Cardiovascular Research, John A. Burns School of Medicine, University of Hawaii, USA
| | - Chrishan J.A. Ramachandra
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore
- Cardiovascular & Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore
| | - Derek J. Hausenloy
- National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore
- Cardiovascular & Metabolic Disorders Program, Duke-National University of Singapore Medical School, Singapore
- Yong Loo Lin School of Medicine, National University Singapore, Singapore
- The Hatter Cardiovascular Institute, University College London, London, UK
- The National Institute of Health Research University College London Hospitals
- Biomedical Research Centre, Research & Development, London, UK
- Tecnologico de Monterrey, Centro de Biotecnologia-FEMSA, Nuevo Leon, Mexico
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39
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van der Velden J, Tocchetti CG, Varricchi G, Bianco A, Sequeira V, Hilfiker-Kleiner D, Hamdani N, Leite-Moreira AF, Mayr M, Falcão-Pires I, Thum T, Dawson DK, Balligand JL, Heymans S. Metabolic changes in hypertrophic cardiomyopathies: scientific update from the Working Group of Myocardial Function of the European Society of Cardiology. Cardiovasc Res 2019; 114:1273-1280. [PMID: 29912308 PMCID: PMC6054261 DOI: 10.1093/cvr/cvy147] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Accepted: 06/13/2018] [Indexed: 12/20/2022] Open
Abstract
Disturbed metabolism as a consequence of obesity and diabetes may cause cardiac diseases (recently highlighted in the cardiovascular research spotlight issue on metabolic cardiomyopathies).1 In turn, the metabolism of the heart may also be disturbed in genetic and acquired forms of hypertrophic cardiac disease. Herein, we provide an overview of recent insights on metabolic changes in genetic hypertrophic cardiomyopathy and discuss several therapies, which may be explored to target disturbed metabolism and prevent onset of cardiac hypertrophy. This article is part of the Mini Review Series from the Varenna 2017 meeting of the Working Group of Myocardial Function of the European Society of Cardiology.
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Affiliation(s)
- Jolanda van der Velden
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands.,Netherlands Heart Institute, Utrecht, The Netherlands
| | - Carlo G Tocchetti
- Department of Translational Medical Sciences, Federico II University, Naples, NA, Italy
| | - Gilda Varricchi
- Department of Translational Medical Sciences, Federico II University, Naples, NA, Italy
| | - Anna Bianco
- Department of Translational Medical Sciences, Federico II University, Naples, NA, Italy.,Department of Cardiology, Maastricht University Medical Center & CARIM, Maastricht University, Maastricht, The Netherlands
| | - Vasco Sequeira
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Denise Hilfiker-Kleiner
- Molecular Cardiology, Department of Cardiology and Angiology, Medical School Hannover, Germany
| | - Nazha Hamdani
- Department of Systems Physiology, Ruhr University Bochum, Bochum, Germany
| | - Adelino F Leite-Moreira
- Department of Surgery and Physiology, Faculty of Medicine, Cardiovascular Research Centre, University of Porto, Porto, Portugal
| | - Manuel Mayr
- The James Black Centre & King's British Heart Foundation Centre, King's College, University of London, London, UK
| | - Ines Falcão-Pires
- Department of Surgery and Physiology, Faculty of Medicine, Cardiovascular Research Centre, University of Porto, Porto, Portugal
| | - Thomas Thum
- Institute of Molecular and Translational Therapeutic Strategies (IMTTS), Hannover Medical School, Hannover, Germany.,National Heart and Lung Institute, Imperial College London, London, UK.,REBIRTH Excellence Cluster, Hannover Medical School, Hannover, Germany
| | - Dana K Dawson
- School of Medicine & Dentistry, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Jean-Luc Balligand
- Pole of Pharmacology and Therapeutics, Institut de Recherche Experimentale et Clinique (IREC), and Clinique Universitaire Saint-Luc, Université catholique de Louvain, Brussels, Belgium
| | - Stephane Heymans
- Netherlands Heart Institute, Utrecht, The Netherlands.,Department of Cardiology, Maastricht University Medical Center & CARIM, Maastricht University, Maastricht, The Netherlands.,Department of Cardiovascular Sciences, Leuven University, Leuven, Belgium
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40
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Sewanan LR, Schwan J, Kluger J, Park J, Jacoby DL, Qyang Y, Campbell SG. Extracellular Matrix From Hypertrophic Myocardium Provokes Impaired Twitch Dynamics in Healthy Cardiomyocytes. JACC Basic Transl Sci 2019; 4:495-505. [PMID: 31468004 PMCID: PMC6712054 DOI: 10.1016/j.jacbts.2019.03.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/11/2019] [Accepted: 03/13/2019] [Indexed: 12/16/2022]
Abstract
The goal of this study was to examine the effects of diseased extracellular matrix on the behavior of healthy heart cells. Myocardium was harvested from a genetically engineered miniature pig carrying the hypertrophic cardiomyopathy mutation MYH7 R403Q and from a wild-type littermate. Engineered heart tissues were created by seeding healthy human induced pluripotent stem cell–derived cardiomyocytes onto thin strips of decellularized porcine myocardium. Engineered heart tissues made from the extracellular matrix of hypertrophic cardiomyopathy hearts exhibit increased stiffness, impaired relaxation, and increased force development. This suggests that diseased extracellular matrix can provoke abnormal contractile behavior in otherwise healthy cardiomyocytes.
Hypertrophic cardiomyopathy (HCM) is often caused by single sarcomeric gene mutations that affect muscle contraction. Pharmacological correction of mutation effects prevents but does not reverse disease in mouse models. Suspecting that diseased extracellular matrix is to blame, we obtained myocardium from a miniature swine model of HCM, decellularized thin slices of the tissue, and re-seeded them with healthy human induced pluripotent stem cell–derived cardiomyocytes. Compared with cardiomyocytes grown on healthy extracellular matrix, those grown on the diseased matrix exhibited prolonged contractions and poor relaxation. This outcome suggests that extracellular matrix abnormalities must be addressed in therapies targeting established HCM.
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Key Words
- CM, cardiomyocyte
- ECM, extracellular matrix
- EHT, engineered heart tissue
- H&E, hematoxylin and eosin
- HCM, hypertrophic cardiomyopathy
- MTR, Masson trichrome
- MUT, minipig carrying MYH7 R403Q mutation
- MYH7 mutation
- RT50, time from peak tension to 50% relaxation
- SR, Sirius red
- TTP, time to peak tension
- WT, wild-type
- cDNA, complementary deoxyribonucleic acid
- diastolic dysfunction
- engineered heart tissue
- fibrosis
- hypertrophic cardiomyopathy
- iPSC, induced pluripotent stem cell
- iPSC-derived cardiomyocyte
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Affiliation(s)
- Lorenzo R Sewanan
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Jonas Schwan
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Jonathan Kluger
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Jinkyu Park
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut.,Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, Connecticut
| | - Daniel L Jacoby
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Yibing Qyang
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut.,Yale Stem Cell Center, Yale University, New Haven, Connecticut.,Department of Pathology, Yale University, New Haven, Connecticut.,Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, Connecticut
| | - Stuart G Campbell
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut.,Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
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41
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Olivotto I, Camici PG, Merlini PA, Rapezzi C, Patten M, Climent V, Sinagra G, Tomberli B, Marin F, Ehlermann P, Maier LS, Fornaro A, Jacobshagen C, Ganau A, Moretti L, Hernandez Madrid A, Coppini R, Reggiardo G, Poggesi C, Fattirolli F, Belardinelli L, Gensini G, Mugelli A. Efficacy of Ranolazine in Patients With Symptomatic Hypertrophic Cardiomyopathy: The RESTYLE-HCM Randomized, Double-Blind, Placebo-Controlled Study. Circ Heart Fail 2019; 11:e004124. [PMID: 29321131 DOI: 10.1161/circheartfailure.117.004124] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 12/18/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND The late sodium current inhibitor ranolazine reverses the main electrophysiological and mechanical abnormalities of human hypertrophic cardiomyopathy (HCM) cardiomyocytes in vitro, suggesting potential clinical benefit. We aimed to assess the effect of ranolazine on functional capacity, symptomatic status, diastolic function, and arrhythmias in HCM. METHODS AND RESULTS In this multicenter, double-blind, phase 2 study, 80 adult patients with nonobstructive HCM (age 53±14 years, 34 women) were randomly assigned to placebo (n=40) or ranolazine 1000 mg bid (n=40) for 5 months. The primary end point was change in peak VO2 compared with baseline using cardiopulmonary exercise test. Echocardiographic lateral and septal E/E' ratio, prohormone brain natriuretic peptide levels, 24-hour Holter arrhythmic profile, and quality of life were assessed. Ranolazine was safe and well tolerated. Overall, there was no significant difference in VO2 peak change at 5 months in the ranolazine versus placebo group (delta 0.15±3.96 versus -0.02±4.25 mL/kg per minute; P=0.832). Ranolazine treatment was associated with a reduction in 24-hour burden of premature ventricular complexes compared with placebo (>50% reduction versus baseline in 61% versus 31%, respectively; P=0.042). However, changes in prohormone brain natriuretic peptide levels did not differ in the ranolazine compared with the placebo group (geometric mean median [interquartile range], -3 pg/mL [-107, 142 pg/mL] versus 78 pg/mL [-71, 242 pg/mL]; P=0.251). Furthermore, E/E' ratio and quality of life scores showed no significant difference. CONCLUSIONS In patients with nonobstructive HCM, ranolazine showed no overall effect on exercise performance, plasma prohormone brain natriuretic peptide levels, diastolic function, or quality of life. The drug showed an excellent safety profile and was associated with reduced premature ventricular complex burden. Late sodium current inhibition does not seem to improve functional capacity in HCM. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrialsregister.eu. Unique identifier: 2011-004507-20.
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Affiliation(s)
- Iacopo Olivotto
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Paolo G Camici
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Piera Angelica Merlini
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Claudio Rapezzi
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Monica Patten
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Vicent Climent
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Gianfranco Sinagra
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Benedetta Tomberli
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.).
| | - Francisco Marin
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Philipp Ehlermann
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Lars S Maier
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Alessandra Fornaro
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Claudius Jacobshagen
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Antonello Ganau
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Luciano Moretti
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Antonio Hernandez Madrid
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Raffaele Coppini
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Giorgio Reggiardo
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Corrado Poggesi
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Francesco Fattirolli
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Luiz Belardinelli
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Gianfranco Gensini
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
| | - Alessandro Mugelli
- >From the Cardiomyopathy Unit, Careggi University Hospital, Florence, Italy (I.O., B.T., A.F.); Vita Salute University and Scientific Institute San Raffaele, Milan, Italy (P.G.C.); Dipartimento Cardiotoracovascolare, Ospedale Niguarda, Milan, Italy (P.A.M.); Ospedale S. Orsola Malpighi, Bologna, Italy (C.R.); Clinic of General and Interventional Cardiology, University Heart Center, Hamburg, Germany (M.P.); Cardiology Department, Hospital General Universitario de Alicante, ISABIAL - FISABIO, Alicante, Spain (V.C.); Cardiovascular Department, Ospedale di Cattinara, Trieste, Italy (G.S.); Hospital Universitario Virgen de la Arrixaca, IMIB-Arrixaca, Murcia, Spain (F.M.); University Hospital, Heidelberg, Germany (P.E.); University Hospital Regensburg, Germany (L.S.M.); Herz zentrum Georg-August-Universitaet, Göttingen, Germany (C.J.); Department of Clinical and Experimental Medicine, Cardiology, Sassari Hospital, Sassari, Italy (A.G.); Ospedale Mazzoni, Ascoli Piceno, Italy (L.M.); Hospital Ramòn y Cajal, Alcalá University, Madrid, Spain (A.H.M.); Department Neurofarba, University of Florence, Italy (R.C., A.M.); Medi Service, Genoa, Italy (G.R.); Department of Experimental and Clinical Medicine, University of Florence, Italy (C.P., F.F.); Gilead Sciences, Foster City, CA (L.B.); and CESMAV, Florence, Italy (G.G.)
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Viola HM, Hool LC. Impaired calcium handling and mitochondrial metabolic dysfunction as early markers of hypertrophic cardiomyopathy. Arch Biochem Biophys 2019; 665:166-174. [PMID: 30885674 DOI: 10.1016/j.abb.2019.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/08/2019] [Accepted: 03/11/2019] [Indexed: 02/07/2023]
Abstract
Hypertrophic cardiomyopathy (HCM) is a primary myocardial disorder, characterised by myocyte remodeling, disorganisation of sarcomeric proteins, impaired energy metabolism and altered cardiac contractility. Gene mutations encoding cardiac contractile proteins account for 60% of HCM aetiology. Current drug therapy including L-type calcium channel antagonists, are used to manage symptoms in patients with overt HCM, but no treatment exists that can reverse or prevent the cardiomyopathy. Design of effective drug therapy will require a clear understanding of the early pathophysiological mechanisms of the disease. Numerous studies have investigated specific aspects of HCM pathophysiology. This review brings these findings together, in order to develop a holistic understanding of the early pathophysiological mechanisms of the disease. We focus on gene mutations in cardiac myosin binding protein-C, β-cardiac myosin heavy chain, cardiac troponin I, and cardiac troponin T, that comprise the majority of all HCM sarcomeric gene mutations. We find that although some similarities exist, each mutation leads to mutation-specific alterations in calcium handling, myofilament calcium sensitivity and mitochondrial metabolic function. This may contribute to the observed clinical phenotypic variability in sarcomeric-related HCM. An understanding of early mutation-specific mechanisms of the disease may provide useful markers of disease progression, and inform therapeutic design.
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Affiliation(s)
- Helena M Viola
- School of Human Sciences (Physiology), The University of Western Australia, Crawley, WA, Australia
| | - Livia C Hool
- School of Human Sciences (Physiology), The University of Western Australia, Crawley, WA, Australia; Victor Chang Cardiac Research Institute, Sydney, NSW, Australia.
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Moving beyond simple answers to complex disorders in sarcomeric cardiomyopathies: the role of integrated systems. Pflugers Arch 2019; 471:661-671. [PMID: 30848350 DOI: 10.1007/s00424-019-02269-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 03/01/2019] [Indexed: 12/26/2022]
Abstract
The classic clinical definition of hypertrophic cardiomyopathy (HCM) as originally described by Teare is deceptively simple, "left ventricular hypertrophy in the absence of any identifiable cause." Longitudinal studies, however, including a seminal study performed by Frank and Braunwald in 1968, clearly described the disorder much as we know it today, a complex, progressive, and highly variable cardiomyopathy affecting ~ 1/500 individuals worldwide. Subsequent genetic linkage studies in the early 1990s identified mutations in virtually all of the protein components of the cardiac sarcomere as the primary molecular cause of HCM. In addition, a substantial proportion of inherited dilated cardiomyopathy (DCM) has also been linked to sarcomeric protein mutations. Despite our deep understanding of the overall function of the sarcomere as the primary driver of cardiac contractility, the ability to use genotype in patient management remains elusive. A persistent challenge in the field from both the biophysical and clinical standpoints is how to rigorously link high-resolution protein dynamics and mechanics to the long-term cardiovascular remodeling process that characterizes these complex disorders. In this review, we will explore the depth of the problem from both the standpoint of a multi-subunit, highly conserved and dynamic "machine" to the resultant clinical and structural human phenotype with an emphasis on new, integrative approaches that can be widely applied to identify both novel disease mechanisms and new therapeutic targets for these primary biophysical disorders of the cardiac sarcomere.
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van der Velden J, Stienen GJM. Cardiac Disorders and Pathophysiology of Sarcomeric Proteins. Physiol Rev 2019; 99:381-426. [PMID: 30379622 DOI: 10.1152/physrev.00040.2017] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The sarcomeric proteins represent the structural building blocks of heart muscle, which are essential for contraction and relaxation. During recent years, it has become evident that posttranslational modifications of sarcomeric proteins, in particular phosphorylation, tune cardiac pump function at rest and during exercise. This delicate, orchestrated interaction is also influenced by mutations, predominantly in sarcomeric proteins, which cause hypertrophic or dilated cardiomyopathy. In this review, we follow a bottom-up approach starting from a description of the basic components of cardiac muscle at the molecular level up to the various forms of cardiac disorders at the organ level. An overview is given of sarcomere changes in acquired and inherited forms of cardiac disease and the underlying disease mechanisms with particular reference to human tissue. A distinction will be made between the primary defect and maladaptive/adaptive secondary changes. Techniques used to unravel functional consequences of disease-induced protein changes are described, and an overview of current and future treatments targeted at sarcomeric proteins is given. The current evidence presented suggests that sarcomeres not only form the basis of cardiac muscle function but also represent a therapeutic target to combat cardiac disease.
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Affiliation(s)
- Jolanda van der Velden
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam , The Netherlands ; and Department of Physiology, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Ger J M Stienen
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam , The Netherlands ; and Department of Physiology, Kilimanjaro Christian Medical University College, Moshi, Tanzania
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Piroddi N, Witjas-Paalberends ER, Ferrara C, Ferrantini C, Vitale G, Scellini B, Wijnker PJM, Sequiera V, Dooijes D, Dos Remedios C, Schlossarek S, Leung MC, Messer A, Ward DG, Biggeri A, Tesi C, Carrier L, Redwood CS, Marston SB, van der Velden J, Poggesi C. The homozygous K280N troponin T mutation alters cross-bridge kinetics and energetics in human HCM. J Gen Physiol 2018; 151:18-29. [PMID: 30578328 PMCID: PMC6314385 DOI: 10.1085/jgp.201812160] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 11/29/2018] [Indexed: 01/24/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomeric proteins, but the pathogenic mechanism is unclear. Piroddi et al. find impairment of cross-bridge kinetics and energetics in human sarcomeres with a TNNT2 mutation, suggesting that HCM involves inefficient ATP utilization. Hypertrophic cardiomyopathy (HCM) is a genetic form of left ventricular hypertrophy, primarily caused by mutations in sarcomere proteins. The cardiac remodeling that occurs as the disease develops can mask the pathogenic impact of the mutation. Here, to discriminate between mutation-induced and disease-related changes in myofilament function, we investigate the pathogenic mechanisms underlying HCM in a patient carrying a homozygous mutation (K280N) in the cardiac troponin T gene (TNNT2), which results in 100% mutant cardiac troponin T. We examine sarcomere mechanics and energetics in K280N-isolated myofibrils and demembranated muscle strips, before and after replacement of the endogenous troponin. We also compare these data to those of control preparations from donor hearts, aortic stenosis patients (LVHao), and HCM patients negative for sarcomeric protein mutations (HCMsmn). The rate constant of tension generation following maximal Ca2+ activation (kACT) and the rate constant of isometric relaxation (slow kREL) are markedly faster in K280N myofibrils than in all control groups. Simultaneous measurements of maximal isometric ATPase activity and Ca2+-activated tension in demembranated muscle strips also demonstrate that the energy cost of tension generation is higher in the K280N than in all controls. Replacement of mutant protein by exchange with wild-type troponin in the K280N preparations reduces kACT, slow kREL, and tension cost close to control values. In donor myofibrils and HCMsmn demembranated strips, replacement of endogenous troponin with troponin containing the K280N mutant increases kACT, slow kREL, and tension cost. The K280N TNNT2 mutation directly alters the apparent cross-bridge kinetics and impairs sarcomere energetics. This result supports the hypothesis that inefficient ATP utilization by myofilaments plays a central role in the pathogenesis of the disease.
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Affiliation(s)
- Nicoletta Piroddi
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy
| | - E Rosalie Witjas-Paalberends
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands
| | - Claudia Ferrara
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy
| | - Cecilia Ferrantini
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy.,LENS, Sesto Fiorentino (Firenze), Florence, Italy
| | - Giulia Vitale
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy
| | - Beatrice Scellini
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy
| | - Paul J M Wijnker
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands
| | - Vasco Sequiera
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands
| | - Dennis Dooijes
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands.,Clinical Genetics, University Medical Center, Utrecht, Netherlands
| | - Cristobal Dos Remedios
- Department of Anatomy and Histology, Bosch Institute, The University of Sydney, Sydney, Australia
| | - Saskia Schlossarek
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,German Centre for Cardiovascular Research (DZHK), partner site Hamburg/Kiel/Lübeck, Germany
| | - Man Ching Leung
- National Heart and Lung Institute, Imperial College, London, England, UK
| | - Andrew Messer
- National Heart and Lung Institute, Imperial College, London, England, UK
| | - Douglas G Ward
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | | | - Chiara Tesi
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy
| | - Lucie Carrier
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,German Centre for Cardiovascular Research (DZHK), partner site Hamburg/Kiel/Lübeck, Germany
| | | | - Steven B Marston
- National Heart and Lung Institute, Imperial College, London, England, UK
| | - Jolanda van der Velden
- Amsterdam UMC, Vrije Universiteit Amsterdam, Physiology, Amsterdam Cardiovascular Sciences, Amsterdam, Netherlands.,Clinical Genetics, University Medical Center, Utrecht, Netherlands.,ICIN-Netherlands, Heart Institute, Utrecht, Netherlands
| | - Corrado Poggesi
- Dipartimento di Medicina Sperimentale e Clinica, Università di Firenze, Florence, Italy .,LENS, Sesto Fiorentino (Firenze), Florence, Italy
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Coppini R, Ferrantini C, Cerbai E. Novel pharmacological approaches for paediatric hypertrophic cardiomyopathy. PROGRESS IN PEDIATRIC CARDIOLOGY 2018. [DOI: 10.1016/j.ppedcard.2018.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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47
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Coppini R, Ferrantini C, Mugelli A, Poggesi C, Cerbai E. Altered Ca 2+ and Na + Homeostasis in Human Hypertrophic Cardiomyopathy: Implications for Arrhythmogenesis. Front Physiol 2018; 9:1391. [PMID: 30420810 PMCID: PMC6215954 DOI: 10.3389/fphys.2018.01391] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/13/2018] [Indexed: 12/12/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is the most common mendelian heart disease, with a prevalence of 1/500. HCM is a primary cause of sudden death, due to an heightened risk of ventricular tachyarrhythmias that often occur in young asymptomatic patients. HCM can slowly progress toward heart failure, either with preserved or reduced ejection fraction, due to worsening of diastolic function. Accumulation of intra-myocardial fibrosis and replacement scars underlies heart failure progression and represents a substrate for sustained arrhythmias in end-stage patients. However, arrhythmias and mechanical abnormalities may occur in hearts with little or no fibrosis, prompting toward functional pathomechanisms. By studying viable cardiomyocytes and trabeculae isolated from inter-ventricular septum samples of non-failing HCM patients with symptomatic obstruction who underwent myectomy operations, we identified that specific abnormalities of intracellular Ca2+ handling are associated with increased cellular arrhytmogenesis and diastolic dysfunction. In HCM cardiomyocytes, diastolic Ca2+ concentration is increased both in the cytosol and in the sarcoplasmic reticulum and the rate of Ca2+ transient decay is slower, while the amplitude of Ca2+-release is preserved. Ca2+ overload is the consequence of an increased Ca2+ entry via L-type Ca2+-current [due to prolongation the action potential (AP) plateau], combined with a reduced rate of Ca2+-extrusion through the Na+/Ca2+ exchanger [due to increased cytosolic (Na+)] and a lower expression of SERCA. Increased late Na+ current (INaL) plays a major role, as it causes both AP prolongation and Na+ overload. Intracellular Ca2+ overload determines an higher frequency of Ca2+ waves leading to delayed-afterdepolarizations (DADs) and premature contractions, but is also linked with the increased diastolic tension and slower relaxation of HCM myocardium. Sustained increase of intracellular [Ca2+] goes hand-in-hand with the increased activation of Ca2+/calmodulin-dependent protein-kinase-II (CaMKII) and augmented phosphorylation of its targets, including Ca2+ handling proteins. In transgenic HCM mouse models, we found that Ca2+ overload, CaMKII and increased INaL drive myocardial remodeling since the earliest stages of disease and underlie the development of hypertrophy, diastolic dysfunction and the arrhythmogenic substrate. In conclusion, diastolic dysfunction and arrhythmogenesis in human HCM myocardium are driven by functional alterations at cellular and molecular level that may be targets of innovative therapies.
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Affiliation(s)
- Raffaele Coppini
- Department of Neuroscience, Psychology, Drug Sciences and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Cecilia Ferrantini
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Alessandro Mugelli
- Department of Neuroscience, Psychology, Drug Sciences and Child Health (NEUROFARBA), University of Florence, Florence, Italy
| | - Corrado Poggesi
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Elisabetta Cerbai
- Department of Neuroscience, Psychology, Drug Sciences and Child Health (NEUROFARBA), University of Florence, Florence, Italy
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48
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Abstract
Hypertrophic cardiomyopathy (HCM) is most commonly transmitted as an autosomal dominant trait, caused by mutations in genes encoding cardiac sarcomere proteins1–3. Other inheritable causes of the disease include mutations in genes coding for proteins important in calcium handling or that form part of the cytoskeleton4–6. At present, the primary clinical role of genetic testing in HCM is to facilitate familial screening to allow the identification of individuals at risk of developing the disease7,8. It is also used to diagnose genocopies, such as lysosomal9–11 and glycogen storage disease which have different treatment strategies, rates of disease progression and prognosis12–14. The role of genetic testing in predicting prognosis is limited at present, but emerging data suggest that knowledge of the genetic basis of disease will assume an important role in disease stratification15–17 and offer potential targets for disease-modifying therapy in the near future18.
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Affiliation(s)
- Mohammed Akhtar
- Bart's Heart Centre, St Bartholomew's Hospital, London & University College London
| | - Perry Elliott
- Bart's Heart Centre, St Bartholomew's Hospital, London & University College London
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49
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Abstract
This article focuses on three "bins" that comprise sets of biophysical derangements elicited by cardiomyopathy-associated mutations in the myofilament. Current therapies focus on symptom palliation and do not address the disease at its core. We and others have proposed that a more nuanced classification could lead to direct interventions based on early dysregulation changing the trajectory of disease progression in the preclinical cohort. Continued research is necessary to address the complexity of cardiomyopathic progression and develop efficacious therapeutics.
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Affiliation(s)
- Melissa L Lynn
- Department of Medicine, University of Arizona, Room 317, 1656 East Mabel Street, Tucson, AZ 85724, USA
| | - Sarah J Lehman
- Department of Physiological Sciences, University of Arizona, Room 317, 1656 East Mabel Street, Tucson, AZ 85724, USA
| | - Jil C Tardiff
- Department of Medicine, University of Arizona, Room 312, 1656 East Mabel Street, Tucson, AZ 85724, USA.
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