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Li Y, Ma K, Dong Z, Gao S, Zhang J, Huang S, Yang J, Fang G, Li Y, Li X, Welch C, Griffin EL, Ramaswamy P, Valivullah Z, Liu X, Dong J, Wang DW, Du, Chung WK, Li Y. Frameshift variants in C10orf71 cause dilated cardiomyopathy in human, mouse, and organoid models. J Clin Invest 2024; 134:e177172. [PMID: 38950288 PMCID: PMC11178530 DOI: 10.1172/jci177172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 04/25/2024] [Indexed: 07/03/2024] Open
Abstract
Research advances over the past 30 years have confirmed a critical role for genetics in the etiology of dilated cardiomyopathies (DCMs). However, full knowledge of the genetic architecture of DCM remains incomplete. We identified candidate DCM causal gene, C10orf71, in a large family with 8 patients with DCM by whole-exome sequencing. Four loss-of-function variants of C10orf71 were subsequently identified in an additional group of492 patients with sporadic DCM from 2 independent cohorts. C10orf71 was found to be an intrinsically disordered protein specifically expressed in cardiomyocytes. C10orf71-KO mice had abnormal heart morphogenesis during embryonic development and cardiac dysfunction as adults with altered expression and splicing of contractile cardiac genes. C10orf71-null cardiomyocytes exhibited impaired contractile function with unaffected sarcomere structure. Cardiomyocytes and heart organoids derived from human induced pluripotent stem cells with C10orf71 frameshift variants also had contractile defects with normal electrophysiological activity. A rescue study using a cardiac myosin activator, omecamtiv mecarbil, restored contractile function in C10orf71-KO mice. These data support C10orf71 as a causal gene for DCM by contributing to the contractile function of cardiomyocytes. Mutation-specific pathophysiology may suggest therapeutic targets and more individualized therapy.
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Affiliation(s)
- Yang Li
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Ke Ma
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Zhujun Dong
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Shijuan Gao
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Jing Zhang
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Shan Huang
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Jie Yang
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Guangming Fang
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Yujie Li
- Novogene Co. Ltd., Beijing, China
| | - Xiaowei Li
- Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Carrie Welch
- Department of Pediatrics, Columbia University, New York, New York, USA
| | - Emily L. Griffin
- Department of Pediatrics, Columbia University, New York, New York, USA
| | | | | | | | - Jianzeng Dong
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Department of Cardiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Dao Wen Wang
- Division of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Du
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
| | - Wendy K. Chung
- Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Yulin Li
- Beijing Anzhen Hospital, Capital Medical University, Beijing, China
- Beijing Institute of Heart, Lung & Blood Vessel Disease, Beijing, China
- The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Ministry of Education, Beijing, China
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2
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Auguin D, Robert-Paganin J, Réty S, Kikuti C, David A, Theumer G, Schmidt AW, Knölker HJ, Houdusse A. Omecamtiv mecarbil and Mavacamten target the same myosin pocket despite opposite effects in heart contraction. Nat Commun 2024; 15:4885. [PMID: 38849353 PMCID: PMC11161628 DOI: 10.1038/s41467-024-47587-9] [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: 10/30/2023] [Accepted: 04/03/2024] [Indexed: 06/09/2024] Open
Abstract
Inherited cardiomyopathies are common cardiac diseases worldwide, leading in the late stage to heart failure and death. The most promising treatments against these diseases are small molecules directly modulating the force produced by β-cardiac myosin, the molecular motor driving heart contraction. Omecamtiv mecarbil and Mavacamten are two such molecules that completed phase 3 clinical trials, and the inhibitor Mavacamten is now approved by the FDA. In contrast to Mavacamten, Omecamtiv mecarbil acts as an activator of cardiac contractility. Here, we reveal by X-ray crystallography that both drugs target the same pocket and stabilize a pre-stroke structural state, with only few local differences. All-atom molecular dynamics simulations reveal how these molecules produce distinct effects in motor allostery thus impacting force production in opposite way. Altogether, our results provide the framework for rational drug development for the purpose of personalized medicine.
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Affiliation(s)
- Daniel Auguin
- Structural Motility, Institut Curie, Université Paris Sciences et Lettres, Sorbonne Université, CNRS UMR144, Paris, 75248, France
- Laboratoire de Physiologie, Ecologie et Environnement (P2E), UPRES EA 1207/USC INRAE-1328, UFR Sciences et Techniques, Université d'Orléans, Orléans, France
| | - Julien Robert-Paganin
- Structural Motility, Institut Curie, Université Paris Sciences et Lettres, Sorbonne Université, CNRS UMR144, Paris, 75248, France
| | - Stéphane Réty
- Laboratoire de Biologie et Modélisation de la Cellule, ENS de Lyon, CNRS, UMR 5239, Inserm, U1293, Université Claude Bernard Lyon 1, Lyon, France
| | - Carlos Kikuti
- Structural Motility, Institut Curie, Université Paris Sciences et Lettres, Sorbonne Université, CNRS UMR144, Paris, 75248, France
| | - Amandine David
- Structural Motility, Institut Curie, Université Paris Sciences et Lettres, Sorbonne Université, CNRS UMR144, Paris, 75248, France
| | | | | | | | - Anne Houdusse
- Structural Motility, Institut Curie, Université Paris Sciences et Lettres, Sorbonne Université, CNRS UMR144, Paris, 75248, France.
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3
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Liang LW, Lumish HS, Sewanan LR, Shimada YJ, Maurer MS, Weiner SD, Clerkin KJ. Evolving Strategies for the Management of Obstructive Hypertrophic Cardiomyopathy. J Card Fail 2024:S1071-9164(24)00183-0. [PMID: 38777216 DOI: 10.1016/j.cardfail.2024.04.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/25/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024]
Abstract
For many years, treatment of hypertrophic cardiomyopathy (HCM) has focused on non-disease-specific therapies. Cardiac myosin modulators (ie, mavacamten and aficamten) reduce the pathologic actin-myosin interactions that are characteristic of HCM, leading to improved cardiac energetics and reduction in hypercontractility. Several recently published randomized clinical trials have demonstrated that mavacamten improves exercise capacity, left ventricular outflow tract obstruction and symptoms in patients with obstructive HCM and may delay the need for septal-reduction therapy. Long-term data in real-world populations will be needed to fully assess the safety and efficacy of mavacamten. Importantly, HCM is a complex and heterogeneous disease, and not all patients will respond to mavacamten; therefore, careful patient selection and shared decision making will be necessary in guiding the use of mavacamten in obstructive HCM.
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Affiliation(s)
- Lusha W Liang
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY
| | - Heidi S Lumish
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY
| | - Lorenzo R Sewanan
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY
| | - Yuichi J Shimada
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY
| | - Mathew S Maurer
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY
| | - Shepard D Weiner
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY
| | - Kevin J Clerkin
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY.
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4
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Donkervoort S, van de Locht M, Ronchi D, Reunert J, McLean CA, Zaki M, Orbach R, de Winter JM, Conijn S, Hoomoedt D, Neto OLA, Magri F, Viaene AN, Foley AR, Gorokhova S, Bolduc V, Hu Y, Acquaye N, Napoli L, Park JH, Immadisetty K, Miles LB, Essawi M, McModie S, Ferreira LF, Zanotti S, Neuhaus SB, Medne L, ElBagoury N, Johnson KR, Zhang Y, Laing NG, Davis MR, Bryson-Richardson RJ, Hwee DT, Hartman JJ, Malik FI, Kekenes-Huskey PM, Comi GP, Sharaf-Eldin W, Marquardt T, Ravenscroft G, Bönnemann CG, Ottenheijm CAC. Pathogenic TNNI1 variants disrupt sarcomere contractility resulting in hypo- and hypercontractile muscle disease. Sci Transl Med 2024; 16:eadg2841. [PMID: 38569017 DOI: 10.1126/scitranslmed.adg2841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 03/11/2024] [Indexed: 04/05/2024]
Abstract
Troponin I (TnI) regulates thin filament activation and muscle contraction. Two isoforms, TnI-fast (TNNI2) and TnI-slow (TNNI1), are predominantly expressed in fast- and slow-twitch myofibers, respectively. TNNI2 variants are a rare cause of arthrogryposis, whereas TNNI1 variants have not been conclusively established to cause skeletal myopathy. We identified recessive loss-of-function TNNI1 variants as well as dominant gain-of-function TNNI1 variants as a cause of muscle disease, each with distinct physiological consequences and disease mechanisms. We identified three families with biallelic TNNI1 variants (F1: p.R14H/c.190-9G>A, F2 and F3: homozygous p.R14C), resulting in loss of function, manifesting with early-onset progressive muscle weakness and rod formation on histology. We also identified two families with a dominantly acting heterozygous TNNI1 variant (F4: p.R174Q and F5: p.K176del), resulting in gain of function, manifesting with muscle cramping, myalgias, and rod formation in F5. In zebrafish, TnI proteins with either of the missense variants (p.R14H; p.R174Q) incorporated into thin filaments. Molecular dynamics simulations suggested that the loss-of-function p.R14H variant decouples TnI from TnC, which was supported by functional studies showing a reduced force response of sarcomeres to submaximal [Ca2+] in patient myofibers. This contractile deficit could be reversed by a slow skeletal muscle troponin activator. In contrast, patient myofibers with the gain-of-function p.R174Q variant showed an increased force to submaximal [Ca2+], which was reversed by the small-molecule drug mavacamten. Our findings demonstrated that TNNI1 variants can cause muscle disease with variant-specific pathomechanisms, manifesting as either a hypo- or a hypercontractile phenotype, suggesting rational therapeutic strategies for each mechanism.
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Affiliation(s)
- Sandra Donkervoort
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Martijn van de Locht
- Department of Physiology, Amsterdam UMC (location VUmc), Amsterdam, 1081 HV Netherlands
| | - Dario Ronchi
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, 20135, Italy
| | - Janine Reunert
- Department of General Pediatrics, University of Münster, Münster, 48149, Germany
| | - Catriona A McLean
- Department of Anatomical Pathology, Alfred Hospital, Melbourne, Victoria, 3004, Australia
- Faculty of Medicine, Nursing, and Health Sciences, Monash University, Melbourne, Victoria, 3168, Australia
| | - Maha Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, 12622, Egypt
| | - Rotem Orbach
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Josine M de Winter
- Department of Physiology, Amsterdam UMC (location VUmc), Amsterdam, 1081 HV Netherlands
| | - Stefan Conijn
- Department of Physiology, Amsterdam UMC (location VUmc), Amsterdam, 1081 HV Netherlands
| | - Daan Hoomoedt
- Department of Physiology, Amsterdam UMC (location VUmc), Amsterdam, 1081 HV Netherlands
| | - Osorio Lopes Abath Neto
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Francesca Magri
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, 20122, Italy
| | - Angela N Viaene
- Department of Pathology and Laboratory Medicine, The Children's Hospital of Philadelphia, University of Pennsylvania Perelman School of Medicine, Philadelphia, 19104 PA, USA
| | - A Reghan Foley
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Svetlana Gorokhova
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- Department of Medical Genetics, Timone Children's Hospital, APHM, Marseille, 13005, France
- INSERM, U1251-MMG, Aix-Marseille Université, Marseille, 13009, France
| | - Véronique Bolduc
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ying Hu
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nicole Acquaye
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Laura Napoli
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, 20122, Italy
| | - Julien H Park
- Department of General Pediatrics, University Hospital Münster, Münster, 48149 Germany
| | - Kalyan Immadisetty
- Department of Cell and Molecular Physiology, Loyola University, Chicago, IL 60153, USA
| | - Lee B Miles
- School of Biological Sciences, Monash University, Melbourne, Victoria, 3800, Australia
| | - Mona Essawi
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, 12622, Egypt
| | - Salar McModie
- Department of Neurology, Alfred Health, Melbourne, Victoria, 3004, Australia
| | - Leonardo F Ferreira
- Department of Physiology, Amsterdam UMC (location VUmc), Amsterdam, 1081 HV Netherlands
- Department of Orthopaedic Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Simona Zanotti
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, 20122, Italy
| | - Sarah B Neuhaus
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Livija Medne
- Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Nagham ElBagoury
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, 12622, Egypt
| | - Kory R Johnson
- Bioinformatics Core, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yong Zhang
- Bioinformatics Core, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Nigel G Laing
- Neurogenetics Unit, Department of Diagnostic Genomics, PathWest Laboratory Medicine, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia
- Centre for Medical Research University of Western Australia, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia
| | - Mark R Davis
- Neurogenetics Unit, Department of Diagnostic Genomics, PathWest Laboratory Medicine, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia
| | | | - Darren T Hwee
- Research and Development, Cytokinetics Inc., South San Francisco, CA 94080, USA
| | - James J Hartman
- Research and Development, Cytokinetics Inc., South San Francisco, CA 94080, USA
| | - Fady I Malik
- Research and Development, Cytokinetics Inc., South San Francisco, CA 94080, USA
| | | | - Giacomo Pietro Comi
- Dino Ferrari Center, Department of Pathophysiology and Transplantation, University of Milan, Milan, 20135, Italy
- Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neuromuscular and Rare Disease Unit, Milan, 20122, Italy
| | - Wessam Sharaf-Eldin
- Medical Molecular Genetics Department, Human Genetics and Genome Research Institute, National Research Centre, Cairo, 12622, Egypt
| | - Thorsten Marquardt
- Department of General Pediatrics, University of Münster, Münster, 48149, Germany
| | - Gianina Ravenscroft
- Centre for Medical Research University of Western Australia, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Western Australia, 6009, Australia
| | - Carsten G Bönnemann
- Neuromuscular and Neurogenetic Disorders of Childhood Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Coen A C Ottenheijm
- Department of Physiology, Amsterdam UMC (location VUmc), Amsterdam, 1081 HV Netherlands
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5
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Kondacs L, Parijat P, Cobb AJA, Kampourakis T. Synthesis and Biophysical Characterization of Fingolimod Derivatives as Cardiac Troponin Antagonists. ACS Med Chem Lett 2024; 15:413-417. [PMID: 38505838 PMCID: PMC10945792 DOI: 10.1021/acsmedchemlett.3c00511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/01/2024] [Accepted: 02/02/2024] [Indexed: 03/21/2024] Open
Abstract
Calcium binding to cardiac troponin C (cTnC) in the thin filaments acts as a trigger for cardiac muscle contraction. The N-lobe of cTnC (NcTnC) undergoes a conformational change in the presence of calcium that allows for interaction with the switch region of cardiac troponin I (cTnISP), releasing its inhibitory effect on the thin filament structure. The small molecule fingolimod inhibits cTnC-cTnISP interactions via electrostatic repulsion between its positively charged tail and positively charged residues in cTnISP and acts as a calcium desensitizer of the contractile myofilaments. Here we investigate the structure-activity relationship of the fingolimod hydrophobic headgroup and show that increasing the alkyl chain length increases both its affinity for NcTnC and its inhibitory effect on the NcTnC-cTnISP interaction and that decreasing flexibility completely abolishes these effects. Strikingly, the longer derivatives have no effect on the calcium affinity of cTnC, suggesting that they act as better inhibitors.
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Affiliation(s)
- Laszlo Kondacs
- Department
of Chemistry, King’s College London, Britannia House, London SE1 1DB, United Kingdom
| | - Priyanka Parijat
- Randall
Centre for Cell and Molecular Biophysics and British Heart Foundation
Centre of Research Excellence, King’s
College London, London SE1 1UL, United Kingdom
| | - Alexander J. A. Cobb
- Department
of Chemistry, King’s College London, Britannia House, London SE1 1DB, United Kingdom
| | - Thomas Kampourakis
- Randall
Centre for Cell and Molecular Biophysics and British Heart Foundation
Centre of Research Excellence, King’s
College London, London SE1 1UL, United Kingdom
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6
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Auguin D, Robert-Paganin J, Réty S, Kikuti C, David A, Theumer G, Schmidt AW, Knölker HJ, Houdusse A. Omecamtiv mecarbil and Mavacamten target the same myosin pocket despite antagonistic effects in heart contraction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.15.567213. [PMID: 38014327 PMCID: PMC10680719 DOI: 10.1101/2023.11.15.567213] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Inherited cardiomyopathies are amongst the most common cardiac diseases worldwide, leading in the late-stage to heart failure and death. The most promising treatments against these diseases are small-molecules directly modulating the force produced by β-cardiac myosin, the molecular motor driving heart contraction. Two of these molecules that produce antagonistic effects on cardiac contractility have completed clinical phase 3 trials: the activator Omecamtiv mecarbil and the inhibitor Mavacamten. In this work, we reveal by X-ray crystallography that both drugs target the same pocket and stabilize a pre-stroke structural state, with only few local differences. All atoms molecular dynamics simulations reveal how these molecules can have antagonistic impact on the allostery of the motor by comparing β-cardiac myosin in the apo form or bound to Omecamtiv mecarbil or Mavacamten. Altogether, our results provide the framework for rational drug development for the purpose of personalized medicine.
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Affiliation(s)
- Daniel Auguin
- Structural Motility, UMR 144 CNRS/Curie Institute, PSL Research University, 26 rue d'Ulm, 75258 Paris cedex 05, France
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d'Orléans, UPRES EA 1207, INRAE- USC1328, F-45067 Orléans, France
| | - Julien Robert-Paganin
- Structural Motility, UMR 144 CNRS/Curie Institute, PSL Research University, 26 rue d'Ulm, 75258 Paris cedex 05, France
| | - Stéphane Réty
- Laboratoire de Biologie et Modélisation de la Cellule, ENS de Lyon, University Claude Bernard, CNRS UMR 5239, INSERM U1210, 46 Allée d'Italie Site Jacques Monod, F-69007 Lyon, France
| | - Carlos Kikuti
- Structural Motility, UMR 144 CNRS/Curie Institute, PSL Research University, 26 rue d'Ulm, 75258 Paris cedex 05, France
| | - Amandine David
- Structural Motility, UMR 144 CNRS/Curie Institute, PSL Research University, 26 rue d'Ulm, 75258 Paris cedex 05, France
| | - Gabriele Theumer
- Faculty of Chemistry, TU Dresden, Bergstraße 66, 01069 Dresden, Germany
| | - Arndt W Schmidt
- Faculty of Chemistry, TU Dresden, Bergstraße 66, 01069 Dresden, Germany
| | | | - Anne Houdusse
- Structural Motility, UMR 144 CNRS/Curie Institute, PSL Research University, 26 rue d'Ulm, 75258 Paris cedex 05, France
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7
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Choi J, Holmes JB, Campbell KS, Stelzer JE. Effect of the Novel Myotrope Danicamtiv on Cross-Bridge Behavior in Human Myocardium. J Am Heart Assoc 2023; 12:e030682. [PMID: 37804193 PMCID: PMC10757519 DOI: 10.1161/jaha.123.030682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 09/13/2023] [Indexed: 10/09/2023]
Abstract
Background Omecamtiv mecarbil (OM) and danicamtiv both increase myocardial force output by selectively activating myosin within the cardiac sarcomere. Enhanced force generation is presumably due to an increase in the total number of myosin heads bound to the actin filament; however, detailed comparisons of the molecular mechanisms of OM and danicamtiv are lacking. Methods and Results The effect of OM and danicamtiv on Ca2+ sensitivity of force generation was analyzed by exposing chemically skinned myocardial samples to a series of increasing Ca2+ solutions. The results showed that OM significantly increased Ca2+ sensitivity of force generation, whereas danicamtiv showed similar Ca2+ sensitivity of force generation to untreated preparations. A direct comparison of OM and danicamtiv on dynamic cross-bridge behavior was performed at a concentration that produced a similar force increase when normalized to predrug levels at submaximal force (pCa 6.1). Both OM and danicamtiv-treated groups slowed the rates of cross-bridge detachment from the strongly bound state and cross-bridge recruitment into the force-producing state. Notably, the significant OM-induced prolongation in the time to reach force relaxation and subsequent commencement of force generation following rapid stretch was dramatically reduced in danicamtiv-treated myocardium. Conclusions This is the first study to directly compare the effects of OM and danicamtiv on cross-bridge kinetics. At a similar level of force enhancement, danicamtiv had a less pronounced effect on the slowing of cross-bridge kinetics and, therefore, may provide a similar improvement in systolic function as OM without excessively prolonging systolic ejection time and slowing cardiac relaxation facilitating diastolic filling at the whole-organ level.
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Affiliation(s)
- Joohee Choi
- Department of Physiology and Biophysics, School of MedicineCase Western Reserve UniversityClevelandOH
| | - Joshua B. Holmes
- Department of Physiology and Biophysics, School of MedicineCase Western Reserve UniversityClevelandOH
| | - Kenneth S. Campbell
- Division of Cardiovascular MedicineUniversity of KentuckyLexingtonKY
- Department of PhysiologyUniversity of KentuckyLexingtonKY
| | - Julian E. Stelzer
- Department of Physiology and Biophysics, School of MedicineCase Western Reserve UniversityClevelandOH
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8
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Ochala J, Lewis CTA, Beck T, Iwamoto H, Hessel AL, Campbell KS, Pyle WG. Predominant myosin superrelaxed state in canine myocardium with naturally occurring dilated cardiomyopathy. Am J Physiol Heart Circ Physiol 2023; 325:H585-H591. [PMID: 37505469 DOI: 10.1152/ajpheart.00369.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 07/12/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023]
Abstract
Dilated cardiomyopathy (DCM) is a naturally occurring heart failure condition in humans and dogs, notably characterized by a reduced contractility and ejection fraction. As the identification of its underlying cellular and molecular mechanisms remain incomplete, the aim of the present study was to assess whether the molecular motor myosin and its known relaxed conformational states are altered in DCM. For that, we dissected and skinned thin cardiac strips from left ventricle obtained from six DCM Doberman Pinschers and six nonfailing (NF) controls. We then used a combination of Mant-ATP chase experiments and X-ray diffraction to assess both energetic and structural changes of myosin. Using the Mant-ATP chase protocol, we observed that in DCM dogs, the amount of myosin molecules in the ATP-conserving conformational state, also known as superrelaxed (SRX), is significantly increased when compared with NF dogs. This alteration can be rescued by applying EMD-57033, a small molecule activating myosin. Conversely, with X-ray diffraction, we found that in DCM dogs, there is a higher proportion of myosin heads in the vicinity of actin when compared with NF dogs (1,0 to 1,1 intensity ratio). Hence, we observed an uncoupling between energetic (Mant-ATP chase) and structural (X-ray diffraction) data. Taken together, these results may indicate that in the heart of Doberman Pinschers with DCM, myosin molecules are potentially stuck in a nonsequestered but ATP-conserving SRX state, that can be counterbalanced by EMD-57033 demonstrating the potential for a myosin-centered pharmacological treatment of DCM.NEW & NOTEWORTHY The key finding of the present study is that, in left ventricles of dogs with a naturally occurring dilated cardiomyopathy, relaxed myosin molecules favor a nonsequestered superrelaxed state potentially impairing sarcomeric contractility. This alteration is rescuable by applying a small molecule activating myosin known as EMD-57033.
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Affiliation(s)
- Julien Ochala
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Thomas Beck
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hiroyuki Iwamoto
- SPring-8, Japan Synchrotron Radiation Research Institute, Hyogo, Japan
| | - Anthony L Hessel
- Institute of Physiology II, University of Muenster, Muenster, Germany
- Accelerated Muscle Biotechnologies, Boston, Massachusetts, United States
| | - Kenneth S Campbell
- Department of Physiology, University of Kentucky, Lexington, Kentucky, United States
- Division of Cardiovascular Medicine, University of Kentucky, Lexington, Kentucky, United States
| | - W Glen Pyle
- IMPART Investigator Team, Dalhousie Medicine, Saint John, New Brunswick, Canada
- Department of Biomedical Sciences, University of Guelph, Guelph, Ontario, Canada
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9
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RabieeRad M, GhasempourDabaghi G, Zare MM, Amani-Beni R. Novel Treatments of Hypertrophic Cardiomyopathy in GDMT for Heart Failure: A State-of-art Review. Curr Probl Cardiol 2023; 48:101740. [PMID: 37054829 DOI: 10.1016/j.cpcardiol.2023.101740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 04/07/2023] [Indexed: 04/15/2023]
Abstract
This state-of-the-art review discuss the available evidence on the use of novel treatments of hypertrophic cardiomyopathy such as omecamtiv mecarbil, EMD-57033, levosimendan, pimobendan, and mavacamten for the treatment of heart failure (HF) in the context of guideline-directed medical therapy (GDMT). The paper provides a detailed overview of these agents' mechanisms of action, potential benefits and limitations, and their effects on clinical outcomes. The review also evaluates the efficacy of the novel treatments in comparison to traditional medications such as digoxin. Finally, we seek to provide insight and guidance to clinicians and researchers in the management of HF patients.
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Affiliation(s)
- Mehrdad RabieeRad
- School of Medicine, Isfahan University of Medical Science, Isfahan, Iran
| | | | - Mohammad M Zare
- School of Medicine, Isfahan University of Medical Science, Isfahan, Iran
| | - Reza Amani-Beni
- School of Medicine, Isfahan University of Medical Science, Isfahan, Iran
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10
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Nag S, Gollapudi SK, Del Rio CL, Spudich JA, McDowell R. Mavacamten, a precision medicine for hypertrophic cardiomyopathy: From a motor protein to patients. SCIENCE ADVANCES 2023; 9:eabo7622. [PMID: 37506209 DOI: 10.1126/sciadv.abo7622] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 06/23/2023] [Indexed: 07/30/2023]
Abstract
Hypertrophic cardiomyopathy (HCM) is a primary myocardial disorder characterized by left ventricular hypertrophy, hyperdynamic contraction, and impaired relaxation of the heart. These functional derangements arise directly from altered sarcomeric function due to either mutations in genes encoding sarcomere proteins, or other defects such as abnormal energetics. Current treatment options do not directly address this causal biology but focus on surgical and extra-sarcomeric (sarcolemmal) pharmacological symptomatic relief. Mavacamten (formerly known as MYK-461), is a small molecule designed to regulate cardiac function at the sarcomere level by selectively but reversibly inhibiting the enzymatic activity of myosin, the fundamental motor of the sarcomere. This review summarizes the mechanism and translational progress of mavacamten from proteins to patients, describing how the mechanism of action and pharmacological characteristics, involving both systolic and diastolic effects, can directly target pathophysiological derangements within the cardiac sarcomere to improve cardiac structure and function in HCM. Mavacamten was approved by the Food and Drug Administration in April 2022 for the treatment of obstructive HCM and now goes by the commercial name of Camzyos. Full information about the risks, limitations, and side effects can be found at www.accessdata.fda.gov/drugsatfda_docs/label/2022/214998s000lbl.pdf.
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Affiliation(s)
- Suman Nag
- MyoKardia Inc., a wholly owned subsidiary of Bristol Myers Squibb, Brisbane, CA 94005, USA
| | - Sampath K Gollapudi
- MyoKardia Inc., a wholly owned subsidiary of Bristol Myers Squibb, Brisbane, CA 94005, USA
| | - Carlos L Del Rio
- MyoKardia Inc., a wholly owned subsidiary of Bristol Myers Squibb, Brisbane, CA 94005, USA
- Cardiac Consulting, 1630 S Delaware St. #56426, San Mateo, CA 94403, USA
| | | | - Robert McDowell
- MyoKardia Inc., a wholly owned subsidiary of Bristol Myers Squibb, Brisbane, CA 94005, USA
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11
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Claassen WJ, Baelde RJ, Galli RA, de Winter JM, Ottenheijm CAC. Small molecule drugs to improve sarcomere function in those with acquired and inherited myopathies. Am J Physiol Cell Physiol 2023; 325:C60-C68. [PMID: 37212548 PMCID: PMC10281779 DOI: 10.1152/ajpcell.00047.2023] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 05/15/2023] [Accepted: 05/15/2023] [Indexed: 05/23/2023]
Abstract
Muscle weakness is a hallmark of inherited or acquired myopathies. It is a major cause of functional impairment and can advance to life-threatening respiratory insufficiency. During the past decade, several small-molecule drugs that improve the contractility of skeletal muscle fibers have been developed. In this review, we provide an overview of the available literature and the mechanisms of action of small-molecule drugs that modulate the contractility of sarcomeres, the smallest contractile units in striated muscle, by acting on myosin and troponin. We also discuss their use in the treatment of skeletal myopathies. The first of three classes of drugs discussed here increase contractility by decreasing the dissociation rate of calcium from troponin and thereby sensitizing the muscle to calcium. The second two classes of drugs directly act on myosin and stimulate or inhibit the kinetics of myosin-actin interactions, which may be useful in patients with muscle weakness or stiffness.NEW & NOTEWORTHY During the past decade, several small molecule drugs that improve the contractility of skeletal muscle fibers have been developed. In this review, we provide an overview of the available literature and the mechanisms of action of small molecule drugs that modulate the contractility of sarcomeres, the smallest contractile units in striated muscle, by acting on myosin and troponin.
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Affiliation(s)
- Wout J Claassen
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan, Amsterdam, Netherlands
| | - Rianne J Baelde
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan, Amsterdam, Netherlands
| | - Ricardo A Galli
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan, Amsterdam, Netherlands
| | - Josine M de Winter
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan, Amsterdam, Netherlands
| | - Coen A C Ottenheijm
- Amsterdam UMC Location Vrije Universiteit Amsterdam, Physiology, De Boelelaan, Amsterdam, Netherlands
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12
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Smith JD, Brawley J, Bordenave KC, Olsen RK, Intasiri A, Cremo CR, Bell TW. Isoform selectivities of novel 4-hydroxycoumarin imines as inhibitors of myosin II. Eur J Med Chem 2023; 247:115008. [PMID: 36543032 PMCID: PMC9889102 DOI: 10.1016/j.ejmech.2022.115008] [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: 10/28/2022] [Accepted: 12/05/2022] [Indexed: 12/14/2022]
Abstract
Muscle myosin inhibition could be used to treat many medical conditions involving hypercontractile states, including muscle spasticity, chronic musculoskeletal pain, and hypertrophic cardiomyopathy. A series of 13 advanced analogs of 3-(N-butylethanimidoyl)ethyl)-4-hydroxy-2H-chromen-2-one (BHC) were synthesized to explore extended imine nitrogen side chains and compare aldimines vs. ketimines. None of the new analogs inhibit nonmuscle myosin in a cytokinesis assay. ATPase structure-activity relationships reveal that selectivity for cardiac vs. skeletal myosin can be tuned with subtle structural changes. None of the compounds inhibited smooth muscle myosin II. Docking the compounds to homology models of cardiac and skeletal myosin II gave rationales for the effects of side arm length on inhibition selectivity and for cardiac vs. skeletal myosin. Properties including solubility, stability and toxicity, suggest that certain BHC analogs may be useful as candidates for preclinical studies or as lead compounds for advanced candidates for drugs with cardiac or skeletal muscle myosin selectivity.
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Affiliation(s)
- Joshua D Smith
- Department of Pharmacology, University of Nevada, School of Medicine, Reno, NV, 89557-0318, USA
| | - Jhonnathan Brawley
- Department of Chemistry, University of Nevada, Reno, NV, 89557-0216, USA
| | - Kate C Bordenave
- Department of Pharmacology, University of Nevada, School of Medicine, Reno, NV, 89557-0318, USA
| | - Ryan K Olsen
- Department of Chemistry, University of Nevada, Reno, NV, 89557-0216, USA
| | - Amarawan Intasiri
- Department of Chemistry, University of Nevada, Reno, NV, 89557-0216, USA
| | - Christine R Cremo
- Department of Pharmacology, University of Nevada, School of Medicine, Reno, NV, 89557-0318, USA.
| | - Thomas W Bell
- Department of Chemistry, University of Nevada, Reno, NV, 89557-0216, USA.
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13
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Marston S, Pinto JR. Suppression of lusitropy as a disease mechanism in cardiomyopathies. Front Cardiovasc Med 2023; 9:1080965. [PMID: 36698941 PMCID: PMC9870330 DOI: 10.3389/fcvm.2022.1080965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
In cardiac muscle the action of adrenaline on β1 receptors of heart muscle cells is essential to adjust cardiac output to the body's needs. Adrenergic activation leads to enhanced contractility (inotropy), faster heart rate (chronotropy) and faster relaxation (lusitropy), mainly through activation of protein kinase A (PKA). Efficient enhancement of heart output under stress requires all of these responses to work together. Lusitropy is essential for shortening the heartbeat when heart rate increases. It therefore follows that, if the lusitropic response is not present, heart function under stress will be compromised. Current literature suggests that lusitropy is primarily achieved due to PKA phosphorylation of troponin I (TnI) and phospholamban (PLB). It has been well documented that PKA-induced phosphorylation of TnI releases Ca2+ from troponin C faster and increases the rate of cardiac muscle relaxation, while phosphorylation of PLB increases SERCA activity, speeding up Ca2+ removal from the cytoplasm. In this review we consider the current scientific evidences for the connection between suppression of lusitropy and cardiac dysfunction in the context of mutations in phospholamban and thin filament proteins that are associated with cardiomyopathies. We will discuss what advances have been made into understanding the physiological mechanism of lusitropy due to TnI and PLB phosphorylation and its suppression by mutations and we will evaluate the evidence whether lack of lusitropy is sufficient to cause cardiomyopathy, and under what circumstances, and consider the range of pathologies associated with loss of lusitropy. Finally, we will discuss whether suppressed lusitropy due to mutations in thin filament proteins can be therapeutically restored.
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Affiliation(s)
- Steven Marston
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Jose Renato Pinto
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States
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14
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Effects of Aficamten on cardiac contractility in a feline translational model of hypertrophic cardiomyopathy. Sci Rep 2023; 13:32. [PMID: 36593243 PMCID: PMC9807554 DOI: 10.1038/s41598-022-26630-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 12/16/2022] [Indexed: 01/03/2023] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is the most prevalent inherited cardiac disease in humans and cats and lacks efficacious pharmacologic interventions in the preclinical phase of disease. LV outflow tract obstruction (LVOTO) is commonly observed in HCM-affected patients and is a primary driver of heart failure symptoms and reduced quality of life. Novel small-molecule cardiac myosin inhibitors target actin-myosin interactions to alleviate overactive protein interactions. A prospective, randomized, controlled cross-over study was performed to evaluate pharmacodynamic effects of two doses (0.3 and 1 mg/kg) of a next-in-class cardiac myosin inhibitor, aficamten (CK-3773274, CK-274), on cardiac function in cats with the A31P MYBPC3 mutation and oHCM. Dose-dependent reductions in LV systolic function, LVOT pressure gradient, and isovolumetric relaxation times compared to baseline were observed. Promising beneficial effects of reduced systolic function warrant further studies of this next-in-class therapeutic to evaluate the benefit of long-term administration in this patient population.
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15
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Sharpe AN, Oldach MS, Kaplan JL, Rivas V, Kovacs SL, Hwee DT, Morgan BP, Malik FI, Harris SP, Stern JA. Pharmacokinetics of a single dose of Aficamten (CK-274) on cardiac contractility in a A31P MYBPC3 hypertrophic cardiomyopathy cat model. J Vet Pharmacol Ther 2023; 46:52-61. [PMID: 36382714 PMCID: PMC10099566 DOI: 10.1111/jvp.13103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 10/06/2022] [Accepted: 10/13/2022] [Indexed: 11/17/2022]
Abstract
Hypertrophic cardiomyopathy (HCM) is the most prevalent cardiac disease in cats and lacks efficacious preclinical pharmacologic intervention, prompting investigation of novel therapies. Genetic mutations encoding sarcomeric proteins are implicated in the development of HCM and small molecule myosin inhibitors are an emerging class of therapeutics designed to target the interaction of actin and myosin to alleviate the detrimental effects of inappropriate contractile protein interactions. The purpose of this study was to characterize the pharmacodynamic effects of a single oral dose of the novel cardiac myosin inhibitor aficamten (CK-274) on cardiac function in purpose bred cats with naturally occurring A31P MYBPC3 mutation and a clinical diagnosis of HCM with left ventricular outflow tract obstruction (LVOTO). Five purpose bred cats were treated with aficamten (2 mg/kg) or vehicle and echocardiographic evaluations were performed at 0, 6, 24, and 48 h post-dosing. High dose aficamten (2 mg/kg) reduced left ventricular fractional shortening (LVFS%) by increasing the LV systolic internal dimension (LVIDs) and reduced isovolumic relaxation time (IVRT) compared with baseline without significant adverse effects. The marked reduction in systolic function and reduced IVRT coupled with an increased heart rate in treated cats, suggest a lower dose may be optimal. Further studies to determine optimal dosing of aficamten are indicated.
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Affiliation(s)
- Ashley N Sharpe
- Department of Medicine and Epidemiology, Davis, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Maureen S Oldach
- Department of Medicine and Epidemiology, Davis, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Joanna L Kaplan
- Department of Medicine and Epidemiology, Davis, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Victor Rivas
- Department of Medicine and Epidemiology, Davis, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Samantha L Kovacs
- Department of Medicine and Epidemiology, Davis, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Darren T Hwee
- Research and Non-clinical Development, Cytokinetics, Inc, South San Francisco, California, USA
| | - Bradley P Morgan
- Research and Non-clinical Development, Cytokinetics, Inc, South San Francisco, California, USA
| | - Fady I Malik
- Research and Non-clinical Development, Cytokinetics, Inc, South San Francisco, California, USA
| | - Samantha P Harris
- Department of Cellular and Molecular Medicine, University of Arizona, Tucson, Arizona, USA
| | - Joshua A Stern
- Department of Medicine and Epidemiology, Davis, School of Veterinary Medicine, University of California, Davis, California, USA
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16
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Ráduly AP, Sárkány F, Kovács MB, Bernát B, Juhász B, Szilvássy Z, Porszász R, Horváth B, Szentandrássy N, Nánási P, Csanádi Z, Édes I, Tóth A, Papp Z, Priksz D, Borbély A. The Novel Cardiac Myosin Activator Danicamtiv Improves Cardiac Systolic Function at the Expense of Diastolic Dysfunction In Vitro and In Vivo: Implications for Clinical Applications. Int J Mol Sci 2022; 24:ijms24010446. [PMID: 36613900 PMCID: PMC9820393 DOI: 10.3390/ijms24010446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/29/2022] Open
Abstract
Recent cardiotropic drug developments have focused on cardiac myofilaments. Danicamtiv, the second direct myosin activator, has achieved encouraging results in preclinical and clinical studies, thus implicating its potential applicability in the treatment of heart failure with reduced ejection fraction (HFrEF). Here, we analyzed the inotropic effects of danicamtiv in detail. To this end, changes in sarcomere length and intracellular Ca2+ levels were monitored in parallel, in enzymatically isolated canine cardiomyocytes, and detailed echocardiographic examinations were performed in anesthetized rats in the absence or presence of danicamtiv. The systolic and diastolic sarcomere lengths decreased; contraction and relaxation kinetics slowed down with increasing danicamtiv concentrations without changes in intracellular Ca2+ transients in vitro. Danicamtiv evoked remarkable increases in left ventricular ejection fraction and fractional shortening, also reflected by changes in systolic strain. Nevertheless, the systolic ejection time was significantly prolonged, the ratio of diastolic to systolic duration was reduced, and signs of diastolic dysfunction were also observed upon danicamtiv treatment in vivo. Taken together, danicamtiv improves cardiac systolic function, but it can also limit diastolic performance, especially at high drug concentrations.
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Affiliation(s)
- Arnold Péter Ráduly
- Division of Clinical Physiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Division of Cardiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Kálmán Laki Doctoral School, University of Debrecen, 4032 Debrecen, Hungary
| | - Fruzsina Sárkány
- Division of Clinical Physiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Kálmán Laki Doctoral School, University of Debrecen, 4032 Debrecen, Hungary
| | - Máté Balázs Kovács
- Division of Clinical Physiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Brigitta Bernát
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Béla Juhász
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Zoltán Szilvássy
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Róbert Porszász
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Balázs Horváth
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Norbert Szentandrássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Department of Basic Medical Sciences, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Péter Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Department of Dental Physiology and Pharmacology, Faculty of Dentistry, University of Debrecen, 4032 Debrecen, Hungary
| | - Zoltán Csanádi
- Division of Cardiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - István Édes
- Division of Cardiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Attila Tóth
- Division of Clinical Physiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Kálmán Laki Doctoral School, University of Debrecen, 4032 Debrecen, Hungary
- HAS-UD Vascular Biology and Myocardial Pathophysiology Research Group, Hungarian Academy of Sciences, 4032 Debrecen, Hungary
| | - Zoltán Papp
- Division of Clinical Physiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Kálmán Laki Doctoral School, University of Debrecen, 4032 Debrecen, Hungary
- HAS-UD Vascular Biology and Myocardial Pathophysiology Research Group, Hungarian Academy of Sciences, 4032 Debrecen, Hungary
- Correspondence: ; Tel.: +36-52-255-978/54329
| | - Dániel Priksz
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
| | - Attila Borbély
- Division of Cardiology, Department of Cardiology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Kálmán Laki Doctoral School, University of Debrecen, 4032 Debrecen, Hungary
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17
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Ma W, Nag S, Gong H, Qi L, Irving TC. Cardiac myosin filaments are directly regulated by calcium. J Gen Physiol 2022; 154:e202213213. [PMID: 36327149 PMCID: PMC9629851 DOI: 10.1085/jgp.202213213] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/25/2022] [Accepted: 10/03/2022] [Indexed: 11/06/2022] Open
Abstract
Classically, striated muscle contraction is initiated by calcium (Ca2+)-dependent structural changes in regulatory proteins on actin-containing thin filaments, which allow the binding of myosin motors to generate force. Additionally, dynamic switching between resting off and active on myosin states has been shown to regulate muscle contractility, a recently validated mechanism by novel myosin-targeted therapeutics. The molecular nature of this switching, however, is not understood. Here, using a combination of small-angle x-ray fiber diffraction and biochemical assays with reconstituted systems, we show that cardiac thick filaments are directly Ca2+-regulated. We find that Ca2+ induces a structural transition of myosin heads from ordered off states close to the thick filament to disordered on states closer to the thin filaments. Biochemical assays show a Ca2+-induced transition from an inactive super-relaxed (SRX) state(s) to an active disordered-relaxed (DRX) state(s) in synthetic thick filaments. We show that these transitions are an intrinsic property of cardiac myosin only when assembled into thick filaments and provide a fresh perspective on nature's two orthogonal mechanisms to regulate muscle contraction through the thin and the thick filaments.
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Affiliation(s)
- Weikang Ma
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL
| | - Suman Nag
- Department of Biochemistry, Bristol Myers Squibb, Brisbane, CA
| | - Henry Gong
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL
| | - Lin Qi
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL
| | - Thomas C. Irving
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL
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18
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Jani V, Qian W, Yuan S, Irving T, Ma W. EMD-57033 Augments the Contractility in Porcine Myocardium by Promoting the Activation of Myosin in Thick Filaments. Int J Mol Sci 2022; 23:14517. [PMID: 36498844 PMCID: PMC9737153 DOI: 10.3390/ijms232314517] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 11/23/2022] Open
Abstract
Sufficient cardiac contractility is necessary to ensure the sufficient cardiac output to provide an adequate end-organ perfusion. Inadequate cardiac output and the diminished perfusion of vital organs from depressed myocardium contractility is a hallmark end-stage of heart failure. There are no available therapeutics that directly target contractile proteins to improve the myocardium contractility and reduce mortality. The purpose of this study is to present a proof of concept to aid in the development of muscle activators (myotropes) for augmenting the contractility in clinical heart failure. Here we use a combination of cardiomyocyte mechanics, the biochemical quantification of the ATP turnover, and small angle X-ray diffraction on a permeabilized porcine myocardium to study the mechanisms of EMD-57033 (EMD) for activating myosin. We show that EMD increases the contractility in a porcine myocardium at submaximal and systolic calcium concentrations. Biochemical assays show that EMD decreases the proportion of myosin heads in the energy sparing super-relaxed (SRX) state under relaxing conditions, which are less likely to interact with actin during contraction. Structural assays show that EMD moves the myosin heads in relaxed muscles from a structurally ordered state close to the thick filament backbone, to a disordered state closer to the actin filament, while simultaneously inducing structural changes in the troponin complex on the actin filament. The dual effects of EMD on activating myosin heads and the troponin complex provides a proof of concept for the use of small molecule muscle activators for augmenting the contractility in heart failure.
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Affiliation(s)
- Vivek Jani
- Department of Biomedical Engineering, The Johns Hopkins School of Medicine, The Johns Hopkins University, Baltimore, MD 20205, USA
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Wenjing Qian
- Department of Biology, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Shengyao Yuan
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Thomas Irving
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Weikang Ma
- BioCAT, Department of Biology, Illinois Institute of Technology, Chicago, IL 60616, USA
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19
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Forouzandehmehr M, Paci M, Koivumäki JT, Hyttinen J. Altered contractility in mutation-specific hypertrophic cardiomyopathy: A mechano-energetic in silico study with pharmacological insights. Front Physiol 2022; 13:1010786. [PMID: 36388127 PMCID: PMC9659818 DOI: 10.3389/fphys.2022.1010786] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 10/14/2022] [Indexed: 07/25/2023] Open
Abstract
Introduction: Mavacamten (MAVA), Blebbistatin (BLEB), and Omecamtiv mecarbil (OM) are promising drugs directly targeting sarcomere dynamics, with demonstrated efficacy against hypertrophic cardiomyopathy (HCM) in (pre)clinical trials. However, the molecular mechanism affecting cardiac contractility regulation, and the diseased cell mechano-energetics are not fully understood yet. Methods: We present a new metabolite-sensitive computational model of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) electromechanics to investigate the pathology of R403Q HCM mutation and the effect of MAVA, BLEB, and OM on the cell mechano-energetics. Results: We offer a mechano-energetic HCM calibration of the model, capturing the prolonged contractile relaxation due to R403Q mutation (∼33%), without assuming any further modifications such as an additional Ca2+ flux to the thin filaments. The HCM model variant correctly predicts the negligible alteration in ATPase activity in R403Q HCM condition compared to normal hiPSC-CMs. The simulated inotropic effects of MAVA, OM, and BLEB, along with the ATPase activities in the control and HCM model variant agree with in vitro results from different labs. The proposed model recapitulates the tension-Ca2+ relationship and action potential duration change due to 1 µM OM and 5 µM BLEB, consistently with in vitro data. Finally, our model replicates the experimental dose-dependent effect of OM and BLEB on the normalized isometric tension. Conclusion: This work is a step toward deep-phenotyping the mutation-specific HCM pathophysiology, manifesting as altered interfilament kinetics. Accordingly, the modeling efforts lend original insights into the MAVA, BLEB, and OM contributions to a new interfilament balance resulting in a cardioprotective effect.
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20
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McMillan SN, Scarff CA. Cryo-electron microscopy analysis of myosin at work and at rest. Curr Opin Struct Biol 2022; 75:102391. [DOI: 10.1016/j.sbi.2022.102391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Revised: 04/18/2022] [Accepted: 04/22/2022] [Indexed: 01/01/2023]
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21
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Bader I, Freilinger M, Landauer F, Waldmüller S, Mueller-Felber W, Rauscher C, Sperl W, Bittner RE, Schmidt WM, Mayr JA. A recurrent single-amino acid deletion (p.Glu500del) in the head domain of ß-cardiac myosin in two unrelated boys presenting with polyhydramnios, congenital axial stiffness and skeletal myopathy. Orphanet J Rare Dis 2022; 17:279. [PMID: 35854315 PMCID: PMC9295345 DOI: 10.1186/s13023-022-02421-7] [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: 02/16/2022] [Accepted: 06/30/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Alterations in the MYH7 gene can cause cardiac and skeletal myopathies. MYH7-related skeletal myopathies are extremely rare, and the vast majority of causal variants in the MYH7 gene are predicted to alter the rod domain of the of ß-cardiac myosin molecule, resulting in distal muscle weakness as the predominant manifestation. Here we describe two unrelated patients harboring an in-frame deletion in the MYH7 gene that is predicted to result in deletion of a single amino acid (p.Glu500del) in the head domain of ß-cardiac myosin. Both patients display an unusual skeletal myopathy phenotype with congenital axial stiffness and muscular hypertonus, but no cardiac involvement. RESULTS Clinical data, MRI results and histopathological data were collected retrospectively in two unrelated boys (9 and 3.5 years old). Exome sequencing uncovered the same 3-bp in-frame deletion in exon 15 (c.1498_1500delGAG) of the MYH7 gene of both patients, a mutation which deletes a highly conserved glutamate residue (p.Glu500del) in the relay loop of the head domain of the ß-cardiac myosin heavy chain. The mutation occurred de novo in one patient, whereas mosaicism was detected in blood of the father of the second patient. Both boys presented with an unusual phenotype of prenatal polyhydramnios, congenital axial stiffness and muscular hypertonus. In one patient the phenotype evolved into an axial/proximal skeletal myopathy without distal involvement or cardiomyopathy, whereas the other patient exhibited predominantly stiffness and respiratory involvement. We review and compare all patients described in the literature who possess a variant predicted to alter the p.Glu500 residue in the ß-cardiac myosin head domain, and we provide in-silico analyses of potential effects on polypeptide function. CONCLUSION The data presented here expand the phenotypic spectrum of mutations in the MYH7 gene and have implications for future diagnostics and therapeutic approaches.
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Affiliation(s)
- Ingrid Bader
- Clinical Genetics Unit, University Hospital, Salzburger Landeskliniken and Paracelsus Medical University Salzburg, 5020, Salzburg, Austria. .,University Children's Hospital, Salzburger Landeskliniken and Paracelsus Medical University Salzburg, 5020, Salzburg, Austria. .,Institute of Medical Genetics and Applied Genomics, University of Tübingen, Calwerstr. 7, 72076, Tübingen, Germany.
| | - M Freilinger
- Universitätsklinik Für Kinder- Und Jugendheilkunde, Medical University of Vienna, 1090, Vienna, Austria
| | - F Landauer
- University Clinic of Orthopaedic and Trauma Surgery, SALK and Paracelsus Medical University Salzburg, 5020, Salzburg, Austria
| | - S Waldmüller
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Calwerstr. 7, 72076, Tübingen, Germany
| | - W Mueller-Felber
- Dr. V. Hauner Children's Hospital, Ludwig-Maximilian University of Munich, Munich, Germany
| | - C Rauscher
- University Children's Hospital, Salzburger Landeskliniken and Paracelsus Medical University Salzburg, 5020, Salzburg, Austria
| | - W Sperl
- University Children's Hospital, Salzburger Landeskliniken and Paracelsus Medical University Salzburg, 5020, Salzburg, Austria
| | - R E Bittner
- Neuromuscular Research Department, Center of Anatomy and Cell Biology, Medical University of Vienna, 1090, Vienna, Austria
| | - W M Schmidt
- Neuromuscular Research Department, Center of Anatomy and Cell Biology, Medical University of Vienna, 1090, Vienna, Austria
| | - J A Mayr
- University Children's Hospital, Salzburger Landeskliniken and Paracelsus Medical University Salzburg, 5020, Salzburg, Austria
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22
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Abstract
Variants in >12 genes encoding sarcomeric proteins can cause various cardiomyopathies. The two most common are hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM). Current therapeutics do not target the root causes of these diseases, but attempt to prevent disease progression and/or to manage symptoms. Accordingly, novel approaches are being developed to treat the cardiac muscle dysfunction directly. Challenges to developing therapeutics for these diseases include the diverse mechanisms of pathogenesis, some of which are still being debated and defined. Four small molecules that modulate the myosin motor protein in the cardiac sarcomere have shown great promise in the settings of HCM and DCM, regardless of the underlying genetic pathogenesis, and similar approaches are being developed to target other components of the sarcomere. In the setting of HCM, mavacamten and aficamten bind to the myosin motor and decrease the ATPase activity of myosin. In the setting of DCM, omecamtiv mecarbil and danicamtiv increase myosin activity in cardiac muscle (but omecamtiv mecarbil decreases myosin activity in vitro). In this Review, we discuss the therapeutic strategies to alter sarcomere contractile activity and summarize the data indicating that targeting one protein in the sarcomere can be effective in treating patients with genetic variants in other sarcomeric proteins, as well as in patients with non-sarcomere-based disease.
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23
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Day SM, Tardiff JC, Ostap EM. Myosin modulators: emerging approaches for the treatment of cardiomyopathies and heart failure. J Clin Invest 2022; 132:148557. [PMID: 35229734 PMCID: PMC8884898 DOI: 10.1172/jci148557] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Myosin modulators are a novel class of pharmaceutical agents that are being developed to treat patients with a range of cardiomyopathies. The therapeutic goal of these drugs is to target cardiac myosins directly to modulate contractility and cardiac power output to alleviate symptoms that lead to heart failure and arrhythmias, without altering calcium signaling. In this Review, we discuss two classes of drugs that have been developed to either activate (omecamtiv mecarbil) or inhibit (mavacamten) cardiac contractility by binding to β-cardiac myosin (MYH7). We discuss progress in understanding the mechanisms by which the drugs alter myosin mechanochemistry, and we provide an appraisal of the results from clinical trials of these drugs, with consideration for the importance of disease heterogeneity and genetic etiology for predicting treatment benefit.
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Affiliation(s)
- Sharlene M Day
- Division of Cardiovascular Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jil C Tardiff
- Department of Biomedical Engineering, University of Arizona, Tucson, Arizona, USA
| | - E Michael Ostap
- Pennsylvania Muscle Institute and Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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24
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Shah AS, Sadayappan S, Urbina EM. Lipids: a Potential Molecular Pathway Towards Diastolic Dysfunction in Youth-Onset Type 2 Diabetes. Curr Atheroscler Rep 2022; 24:109-117. [PMID: 35080716 PMCID: PMC8930525 DOI: 10.1007/s11883-022-00989-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2021] [Indexed: 02/03/2023]
Abstract
PURPOSE OF THE REVIEW Obesity and type 2 diabetes (T2D) with onset in youth are emerging public health concerns. Youth with obesity and T2D are at risk for the development of heart failure with preserved ejection fraction (HFpEF) due to diabetes-related cardiomyopathy with evidence of precursor stages, namely diastolic dysfunction, present in youth. We review the literature regarding diastolic dysfunction in youth with obesity and T2D; discuss the potential mechanisms including the role of lipids, contractile proteins and their post-translational modifications, and conclude with studies to guide future treatments. RECENT FINDINGS The diabetes milieu namely hyperglycemia, hyperinsulinemia, and lipotoxicity favor development of diastolic dysfunction and HFpEF. Recent studies show HFpEF is associated with slow left ventricular relaxation and sarcomere stiffness induced by reduced calcium (Ca2+) and β-adrenergic responses. There are currently no effective therapies available for treating HFpEF. Targeting the sarcomere is an area of ongoing research.
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Affiliation(s)
- Amy S. Shah
- Department of Pediatrics, Division of Endocrinology, Cincinnati Children’s Hospital Medical Center and The University of Cincinnati, 3333 Burnet Ave ML 7012, Cincinnati, OH, 45229, USA
| | - Sakthivel Sadayappan
- Division of Cardiovascular Health and Disease, Department of Internal Medicine, Heart, Lung and Vascular Institute, University of Cincinnati, Cincinnati, Ohio, USA
| | - Elaine M. Urbina
- Department of Pediatrics, Division of Endocrinology, Cincinnati Children’s Hospital Medical Center and The University of Cincinnati, 3333 Burnet Ave ML 7012, Cincinnati, OH, 45229, USA,The Heart Institute, Cincinnati Children’s Hospital, and the University of Cincinnati, Cincinnati, Ohio, USA
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25
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Kosta S, Colli D, Ye Q, Campbell KS. FiberSim: A flexible open-source model of myofilament-level contraction. Biophys J 2022; 121:175-182. [PMID: 34932957 PMCID: PMC8790209 DOI: 10.1016/j.bpj.2021.12.021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/31/2021] [Accepted: 12/16/2021] [Indexed: 01/25/2023] Open
Abstract
FiberSim is a flexible open-source model of myofilament-level contraction. The code uses a spatially explicit technique, meaning that it tracks the position and status of each contractile molecule within the lattice framework. This allows the model to simulate some of the mechanical effects modulated by myosin-binding protein C, as well as the dose dependence of myotropes and the effects of varying isoform expression levels. This paper provides a short introduction to FiberSim and presents simulations of tension-pCa curves with and without regulation of thick and thin filament activation by myosin-binding protein C. A myotrope dose-dependent response as well as slack/re-stretch maneuvers to assess rates of tension recovery are also presented. The software was designed to be flexible (the user can define their own model and/or protocol) and computationally efficient (simulations can be performed on a regular laptop). We hope that other investigators will use FiberSim to explore myofilament level mechanisms and to accelerate research focusing on the contractile properties of sarcomeres.
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Affiliation(s)
- Sarah Kosta
- Department of Physiology, University of Kentucky, Lexington, Kentucky.
| | - Dylan Colli
- Department of Physiology, University of Kentucky, Lexington, Kentucky
| | - Qiang Ye
- Department of Mathematics, University of Kentucky, Lexington, Kentucky
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26
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Papadaki M, Kampaengsri T, Barrick SK, Campbell SG, von Lewinski D, Rainer PP, Harris SP, Greenberg MJ, Kirk JA. Myofilament glycation in diabetes reduces contractility by inhibiting tropomyosin movement, is rescued by cMyBPC domains. J Mol Cell Cardiol 2022; 162:1-9. [PMID: 34487755 PMCID: PMC8766917 DOI: 10.1016/j.yjmcc.2021.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/21/2021] [Accepted: 08/19/2021] [Indexed: 01/17/2023]
Abstract
Diabetes doubles the risk of developing heart failure (HF). As the prevalence of diabetes grows, so will HF unless the mechanisms connecting these diseases can be identified. Methylglyoxal (MG) is a glycolysis by-product that forms irreversible modifications on lysine and arginine, called glycation. We previously found that myofilament MG glycation causes sarcomere contractile dysfunction and is increased in patients with diabetes and HF. The aim of this study was to discover the molecular mechanisms by which MG glycation of myofilament proteins cause sarcomere dysfunction and to identify therapeutic avenues to compensate. In humans with type 2 diabetes without HF, we found increased glycation of sarcomeric actin compared to non-diabetics and it correlated with decreased calcium sensitivity. Depressed calcium sensitivity is pathogenic for HF, therefore myofilament glycation represents a promising therapeutic target to inhibit the development of HF in diabetics. To identify possible therapeutic targets, we further defined the molecular actions of myofilament glycation. Skinned myocytes exposed to 100 μM MG exhibited decreased calcium sensitivity, maximal calcium-activated force, and crossbridge kinetics. Replicating MG's functional affects using a computer simulation of sarcomere function predicted simultaneous decreases in tropomyosin's blocked-to-closed rate transition and crossbridge duty cycle were consistent with all experimental findings. Stopped-flow experiments and ATPase activity confirmed MG decreased the blocked-to-closed transition rate. Currently, no therapeutics target tropomyosin, so as proof-of-principal, we used a n-terminal peptide of myosin-binding protein C, previously shown to alter tropomyosin's position on actin. C0C2 completely rescued MG-induced calcium desensitization, suggesting a possible treatment for diabetic HF.
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Affiliation(s)
- Maria Papadaki
- Department of Cell and Molecular Physiology, Loyola University of Chicago, Maywood, Illinois, USA
| | - Theerachat Kampaengsri
- Department of Cell and Molecular Physiology, Loyola University of Chicago, Maywood, Illinois, USA
| | - Samantha K. Barrick
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, St Louis, Missouri, USA
| | - Stuart G. Campbell
- Department of Bioengineering, Yale University, New Haven, Connecticut, USA
| | | | - Peter P. Rainer
- Division of Cardiology, Medical University of Graz, Graz, Austria
| | - Samantha P. Harris
- Department of Cellular and Molecular Medicine, The University of Arizona, Tucson, Arizona, USA
| | - Michael J. Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, St Louis, Missouri, USA
| | - Jonathan A. Kirk
- Department of Cell and Molecular Physiology, Loyola University of Chicago, Maywood, Illinois, USA,Corresponding Author: Jonathan A. Kirk, Ph.D., Department of Cell and Molecular Physiology, Loyola University Chicago Stritch School of Medicine, Center for Translational Research and Education, Room 522, 2160 S. First Ave., Maywood, IL 60153, Ph: 708-216-6348,
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27
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Parker LE, Landstrom AP. The clinical utility of pediatric cardiomyopathy genetic testing: From diagnosis to a precision medicine-based approach to care. PROGRESS IN PEDIATRIC CARDIOLOGY 2021; 62. [PMID: 34776723 DOI: 10.1016/j.ppedcard.2021.101413] [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] [Indexed: 12/21/2022]
Abstract
Background Pediatric-onset cardiomyopathies are rare yet cause significant morbidity and mortality in affected children. Genetic testing has a major role in the clinical evaluation of pediatric-onset cardiomyopathies, and identification of a variant in an associated gene can be used to confirm the clinical diagnosis and exclude syndromic causes that may warrant different treatment strategies. Further, risk-predictive testing of first-degree relatives can assess who is at-risk of disease and requires continued clinical follow-up. Aim of Review In this review, we seek to describe the current role of genetic testing in the clinical diagnosis and management of patients and families with the five major cardiomyopathies. Further, we highlight the ongoing development of precision-based approaches to diagnosis, prognosis, and treatment. Key Scientific Concepts of Review Emerging application of genotype-phenotype correlations opens the door for genetics to guide a precision medicine-based approach to prognosis and potentially for therapies. Despite advances in our understanding of the genetic etiology of cardiomyopathy and increased accessibility of clinical genetic testing, not all pediatric cardiomyopathy patients have a clear genetic explanation for their disease. Expanded genomic studies are needed to understand the cause of disease in these patients, improve variant classification and genotype-driven prognostic predictions, and ultimately develop truly disease preventing treatment.
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Affiliation(s)
- Lauren E Parker
- Department of Pediatrics, Division of Cardiology, Duke University School of Medicine, Durham, NC, United States
| | - Andrew P Landstrom
- Department of Pediatrics, Division of Cardiology, Duke University School of Medicine, Durham, NC, United States.,Department of Cell Biology, Duke University School of Medicine, Durham, NC, United States
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28
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Hassoun R, Budde H, Mügge A, Hamdani N. Cardiomyocyte Dysfunction in Inherited Cardiomyopathies. Int J Mol Sci 2021; 22:11154. [PMID: 34681814 PMCID: PMC8541428 DOI: 10.3390/ijms222011154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 10/08/2021] [Accepted: 10/13/2021] [Indexed: 01/10/2023] Open
Abstract
Inherited cardiomyopathies form a heterogenous group of disorders that affect the structure and function of the heart. Defects in the genes encoding sarcomeric proteins are associated with various perturbations that induce contractile dysfunction and promote disease development. In this review we aimed to outline the functional consequences of the major inherited cardiomyopathies in terms of myocardial contraction and kinetics, and to highlight the structural and functional alterations in some sarcomeric variants that have been demonstrated to be involved in the pathogenesis of the inherited cardiomyopathies. A particular focus was made on mutation-induced alterations in cardiomyocyte mechanics. Since no disease-specific treatments for familial cardiomyopathies exist, several novel agents have been developed to modulate sarcomere contractility. Understanding the molecular basis of the disease opens new avenues for the development of new therapies. Furthermore, the earlier the awareness of the genetic defect, the better the clinical prognostication would be for patients and the better the prevention of development of the disease.
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Affiliation(s)
- Roua Hassoun
- Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, 44801 Bochum, Germany
- Department of Cardiology, St. Josef-Hospital and Bergmannsheil, Ruhr University Bochum, 44801 Bochum, Germany
| | - Heidi Budde
- Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, 44801 Bochum, Germany
- Department of Cardiology, St. Josef-Hospital and Bergmannsheil, Ruhr University Bochum, 44801 Bochum, Germany
| | - Andreas Mügge
- Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, 44801 Bochum, Germany
- Department of Cardiology, St. Josef-Hospital and Bergmannsheil, Ruhr University Bochum, 44801 Bochum, Germany
| | - Nazha Hamdani
- Institut für Forschung und Lehre (IFL), Molecular and Experimental Cardiology, Ruhr University Bochum, 44801 Bochum, Germany
- Department of Cardiology, St. Josef-Hospital and Bergmannsheil, Ruhr University Bochum, 44801 Bochum, Germany
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29
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Trujillo AS, Hsu KH, Puthawala J, Viswanathan MC, Loya A, Irving TC, Cammarato A, Swank DM, Bernstein SI. Myosin dilated cardiomyopathy mutation S532P disrupts actomyosin interactions, leading to altered muscle kinetics, reduced locomotion, and cardiac dilation in Drosophila. Mol Biol Cell 2021; 32:1690-1706. [PMID: 34081531 PMCID: PMC8684735 DOI: 10.1091/mbc.e21-02-0088] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Dilated cardiomyopathy (DCM), a life-threatening disease characterized by pathological heart enlargement, can be caused by myosin mutations that reduce contractile function. To better define the mechanistic basis of this disease, we employed the powerful genetic and integrative approaches available in Drosophila melanogaster. To this end, we generated and analyzed the first fly model of human myosin-induced DCM. The model reproduces the S532P human β-cardiac myosin heavy chain DCM mutation, which is located within an actin-binding region of the motor domain. In concordance with the mutation's location at the actomyosin interface, steady-state ATPase and muscle mechanics experiments revealed that the S532P mutation reduces the rates of actin-dependent ATPase activity and actin binding and increases the rate of actin detachment. The depressed function of this myosin form reduces the number of cross-bridges during active wing beating, the power output of indirect flight muscles, and flight ability. Further, S532P mutant hearts exhibit cardiac dilation that is mutant gene dose-dependent. Our study shows that Drosophila can faithfully model various aspects of human DCM phenotypes and suggests that impaired actomyosin interactions in S532P myosin induce contractile deficits that trigger the disease.
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Affiliation(s)
- Adriana S Trujillo
- Department of Biology, Molecular Biology Institute, Heart Institute, San Diego State University, San Diego, CA 92182
| | - Karen H Hsu
- Department of Biology, Molecular Biology Institute, Heart Institute, San Diego State University, San Diego, CA 92182
| | - Joy Puthawala
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Meera C Viswanathan
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD 21205
| | - Amy Loya
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Thomas C Irving
- Center for Synchrotron Radiation Research and Instrumentation and Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL 60616
| | - Anthony Cammarato
- Division of Cardiology, Department of Medicine, Johns Hopkins University, Baltimore, MD 21205
| | - Douglas M Swank
- Department of Biological Sciences and Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180
| | - Sanford I Bernstein
- Department of Biology, Molecular Biology Institute, Heart Institute, San Diego State University, San Diego, CA 92182
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30
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Abstract
Despite multiple attempts to develop a unifying hypothesis that explains the pathophysiology of heart failure with a reduced ejection fraction (HFrEF), no single conceptual model has withstood the test of time. In the present review, we discuss how the results of recent successful phase III clinical development programs in HFrEF are built upon existing conceptual models for drug development. We will also discuss where recent successes in clinical trials do not fit existing models to identify areas where further refinement of current paradigms may be needed. To provide the necessary structure for this review, we will begin with a brief overview of the pathophysiology of HFrEF, followed by an overview of the current conceptual models for HFrEF, and end with an analysis of the scientific rationale and clinical development programs for 4 new therapeutic classes of drugs that have improved clinical outcomes in HFrEF. The 4 new therapeutic classes discussed are ARNIs, SGLT2 (sodium-glucose cotransporter 2) inhibitors, soluble guanylate cyclase stimulators, and myosin activators. With the exception of SGLT2 inhibitors, each of these therapeutic advances was informed by the insights provided by existing conceptual models of heart failure. Although the quest to determine the mechanism of action of SGLT2 inhibitors is ongoing, this therapeutic class of drugs may represent the most important advance in cardiovascular therapeutics of recent decades and may lead to rethinking or expanding our current conceptual models for HFrEF.
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Affiliation(s)
- Douglas L Mann
- Center for Cardiovascular Research, Washington University School of Medicine, St. Louis, MO (D.L.M.)
| | - G Michael Felker
- Duke Clinical Research Institute and Duke University School of Medicine, Durham, Duke University, NC (G.M.F.)
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31
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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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32
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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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Solís C, Solaro RJ. Novel insights into sarcomere regulatory systems control of cardiac thin filament activation. J Gen Physiol 2021; 153:211903. [PMID: 33740037 PMCID: PMC7988513 DOI: 10.1085/jgp.202012777] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 02/23/2021] [Indexed: 12/11/2022] Open
Abstract
Our review focuses on sarcomere regulatory mechanisms with a discussion of cardiac-specific modifications to the three-state model of thin filament activation from a blocked to closed to open state. We discuss modulation of these thin filament transitions by Ca2+, by crossbridge interactions, and by thick filament–associated proteins, cardiac myosin–binding protein C (cMyBP-C), cardiac regulatory light chain (cRLC), and titin. Emerging evidence supports the idea that the cooperative activation of the thin filaments despite a single Ca2+ triggering regulatory site on troponin C (cTnC) cannot be considered in isolation of other functional domains of the sarcomere. We discuss long- and short-range interactions among these domains with the regulatory units of thin filaments, including proteins at the barbed end at the Z-disc and the pointed end near the M-band. Important to these discussions is the ever-increasing understanding of the role of cMyBP-C, cRLC, and titin filaments. Detailed knowledge of these control processes is critical to the understanding of mechanisms sustaining physiological cardiac state with varying hemodynamic load, to better defining genetic and acquired cardiac disorders, and to developing targets for therapies at the level of the sarcomeres.
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Affiliation(s)
- Christopher Solís
- University of Illinois at Chicago, College of Medicine, Department of Physiology and Biophysics and Center for Cardiovascular Research, Chicago, IL
| | - R John Solaro
- University of Illinois at Chicago, College of Medicine, Department of Physiology and Biophysics and Center for Cardiovascular Research, Chicago, IL
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Roopnarine O, Thomas DD. Mechanistic analysis of actin-binding compounds that affect the kinetics of cardiac myosin-actin interaction. J Biol Chem 2021; 296:100471. [PMID: 33639160 PMCID: PMC8063737 DOI: 10.1016/j.jbc.2021.100471] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 02/15/2021] [Accepted: 02/23/2021] [Indexed: 12/30/2022] Open
Abstract
Actin-myosin mediated contractile forces are crucial for many cellular functions, including cell motility, cytokinesis, and muscle contraction. We determined the effects of ten actin-binding compounds on the interaction of cardiac myosin subfragment 1 (S1) with pyrene-labeled F-actin (PFA). These compounds, previously identified from a small-molecule high-throughput screen (HTS), perturb the structural dynamics of actin and the steady-state actin-activated myosin ATPase activity. However, the mechanisms underpinning these perturbations remain unclear. Here we further characterize them by measuring their effects on PFA fluorescence, which is decreased specifically by the strong binding of myosin to actin. We measured these effects under equilibrium and steady-state conditions, and under transient conditions, in stopped-flow experiments following addition of ATP to S1-bound PFA. We observed that these compounds affect early steps of the myosin ATPase cycle to different extents. They increased the association equilibrium constant K1 for the formation of the strongly bound collision complex, indicating increased ATP affinity for actin-bound myosin, and decreased the rate constant k+2 for subsequent isomerization to the weakly bound ternary complex, thus slowing the strong-to-weak transition that actin-myosin interaction undergoes early in the ATPase cycle. The compounds' effects on actin structure allosterically inhibit the kinetics of the actin-myosin interaction in ways that may be desirable for treatment of hypercontractile forms of cardiomyopathy. This work helps to elucidate the mechanisms of action for these compounds, several of which are currently used therapeutically, and sets the stage for future HTS campaigns that aim to discover new drugs for treatment of heart failure.
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Affiliation(s)
- Osha Roopnarine
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota , USA.
| | - David D Thomas
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota , USA
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Cirilo JA, Gunther LK, Yengo CM. Functional Role of Class III Myosins in Hair Cells. Front Cell Dev Biol 2021; 9:643856. [PMID: 33718386 PMCID: PMC7947357 DOI: 10.3389/fcell.2021.643856] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/01/2021] [Indexed: 11/14/2022] Open
Abstract
Cytoskeletal motors produce force and motion using the energy from ATP hydrolysis and function in a variety of mechanical roles in cells including muscle contraction, cargo transport, and cell division. Actin-based myosin motors have been shown to play crucial roles in the development and function of the stereocilia of auditory and vestibular inner ear hair cells. Hair cells can contain hundreds of stereocilia, which rely on myosin motors to elongate, organize, and stabilize their structure. Mutations in many stereocilia-associated myosins have been shown to cause hearing loss in both humans and animal models suggesting that each myosin isoform has a specific function in these unique parallel actin bundle-based protrusions. Here we review what is known about the classes of myosins that function in the stereocilia, with a special focus on class III myosins that harbor point mutations associated with delayed onset hearing loss. Much has been learned about the role of the two class III myosin isoforms, MYO3A and MYO3B, in maintaining the precise stereocilia lengths required for normal hearing. We propose a model for how class III myosins play a key role in regulating stereocilia lengths and demonstrate how their motor and regulatory properties are particularly well suited for this function. We conclude that ongoing studies on class III myosins and other stereocilia-associated myosins are extremely important and may lead to novel therapeutic strategies for the treatment of hearing loss due to stereocilia degeneration.
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Affiliation(s)
- Joseph A Cirilo
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA, United States
| | - Laura K Gunther
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA, United States
| | - Christopher M Yengo
- Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey, PA, United States
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