1
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Saad NS, Mashali MA, Repas SJ, Janssen PML. Altering Calcium Sensitivity in Heart Failure: A Crossroads of Disease Etiology and Therapeutic Innovation. Int J Mol Sci 2023; 24:17577. [PMID: 38139404 PMCID: PMC10744146 DOI: 10.3390/ijms242417577] [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: 11/20/2023] [Revised: 12/14/2023] [Accepted: 12/15/2023] [Indexed: 12/24/2023] Open
Abstract
Heart failure (HF) presents a significant clinical challenge, with current treatments mainly easing symptoms without stopping disease progression. The targeting of calcium (Ca2+) regulation is emerging as a key area for innovative HF treatments that could significantly alter disease outcomes and enhance cardiac function. In this review, we aim to explore the implications of altered Ca2+ sensitivity, a key determinant of cardiac muscle force, in HF, including its roles during systole and diastole and its association with different HF types-HF with preserved and reduced ejection fraction (HFpEF and HFrEF, respectively). We further highlight the role of the two rate constants kon (Ca2+ binding to Troponin C) and koff (its dissociation) to fully comprehend how changes in Ca2+ sensitivity impact heart function. Additionally, we examine how increased Ca2+ sensitivity, while boosting systolic function, also presents diastolic risks, potentially leading to arrhythmias and sudden cardiac death. This suggests that strategies aimed at moderating myofilament Ca2+ sensitivity could revolutionize anti-arrhythmic approaches, reshaping the HF treatment landscape. In conclusion, we emphasize the need for precision in therapeutic approaches targeting Ca2+ sensitivity and call for comprehensive research into the complex interactions between Ca2+ regulation, myofilament sensitivity, and their clinical manifestations in HF.
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Affiliation(s)
- Nancy S. Saad
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA;
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Helwan University, Cairo 11795, Egypt
| | - Mohammed A. Mashali
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA;
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
- Department of Surgery, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22514, Egypt
| | - Steven J. Repas
- Department of Emergency Medicine, Wright State University Boonshoft School of Medicine, Dayton, OH 45324, USA;
| | - Paul M. L. Janssen
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA;
- Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
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2
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Zhao X, Liu H, Tian W, Fang L, Yu M, Wu X, Liu A, Wan R, Li L, Luo J, Li Y, Liu B, He Y, Chen X, Li Y, Xu D, Wang H, Han X. Safety, tolerability, pharmacokinetics, and pharmacodynamics of single and multiple doses of aficamten in healthy Chinese participants: a randomized, double-blind, placebo-controlled, phase 1 study. Front Pharmacol 2023; 14:1227470. [PMID: 37680714 PMCID: PMC10482267 DOI: 10.3389/fphar.2023.1227470] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 08/10/2023] [Indexed: 09/09/2023] Open
Abstract
Objectives: Aficamten is a selective, small-molecule allosteric inhibitor of cardiac sarcomere being developed as a chronic oral treatment for patients with symptomatic obstructive hypertrophic cardiomyopathy. This was the first-in-Chinese study aiming to investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of aficamten in healthy adults. Methods: This double-blind, randomized, placebo-controlled, phase 1 study was conducted in 28 healthy male and female Chinese participants after single ascending dose (SAD) and multi-dose (MD) administrations of aficamten. In the SAD cohort, 16 participants were randomized to receive a single oral dose of aficamten: 10 mg, 20 mg, or placebo. In the MD cohort, 12 participants were randomized to receive multiple doses of aficamten: 5 mg or placebo once daily for 14 days. Safety was monitored throughout the study with electrocardiograms, echocardiograms, clinical laboratory tests, and reporting of adverse events (AEs). Pharmacokinetic profiles of aficamten and metabolites, as well as CYP2D6 genetic impact, were evaluated. Results: A total of 35 treatment-emergent AEs were reported by 14 (50%) participants with mild severity. There were no serious AEs or adverse decreases in left ventricular ejection fraction below 50% during the study. Aficamten was dose-proportional over the dose range of 5-20 mg and accumulated in the MD cohort. Conclusion: Aficamten was safe and well-tolerated in the healthy Chinese adult participants. The pharmacokinetics of aficamten in the Chinese population was comparable to those previously found in Western participants. These phase 1 data support the progression of aficamten into future clinical studies in Chinese patients. Clinical Trial registration: https://clinicaltrials.gov, identifier: NCT04783766.
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Affiliation(s)
- Xue Zhao
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Hongzhong Liu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Wei Tian
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Ligang Fang
- Internal Medicine-Cardiovascular Department, Peking Union Medical College Hospital, Beijing, China
| | - Mengyang Yu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Xiaofei Wu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Aijing Liu
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Ruijie Wan
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Li Li
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Jinghui Luo
- Ji Xing Pharmaceuticals (Shanghai) Co., Ltd., Shanghai, China
| | - Yuqiong Li
- Ji Xing Pharmaceuticals (Shanghai) Co., Ltd., Shanghai, China
| | - Bo Liu
- Ji Xing Pharmaceuticals (Shanghai) Co., Ltd., Shanghai, China
| | - Yu He
- Ji Xing Pharmaceuticals (Shanghai) Co., Ltd., Shanghai, China
| | - Xiaowen Chen
- Ji Xing Pharmaceuticals (Shanghai) Co., Ltd., Shanghai, China
| | - Yuan Li
- Ji Xing Pharmaceuticals (Shanghai) Co., Ltd., Shanghai, China
| | - Donghong Xu
- Cytokinetics, Incorporated, South San Francisco, CA, United States
| | - Hongyun Wang
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
| | - Xiaohong Han
- Clinical Pharmacology Research Center, Peking Union Medical College Hospital, Beijing, China
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3
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Hesaraki M, Bora U, Pahlavan S, Salehi N, Mousavi SA, Barekat M, Rasouli SJ, Baharvand H, Ozhan G, Totonchi M. A Novel Missense Variant in Actin Binding Domain of MYH7 Is Associated With Left Ventricular Noncompaction. Front Cardiovasc Med 2022; 9:839862. [PMID: 35463789 PMCID: PMC9024299 DOI: 10.3389/fcvm.2022.839862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 02/22/2022] [Indexed: 11/17/2022] Open
Abstract
Cardiomyopathies are a group of common heart disorders that affect numerous people worldwide. Left ventricular non-compaction (LVNC) is a structural disorder of the ventricular wall, categorized as a type of cardiomyopathy that mostly caused by genetic disorders. Genetic variations are underlying causes of developmental deformation of the heart wall and the resultant contractile insufficiency. Here, we investigated a family with several affected members exhibiting LVNC phenotype. By whole-exome sequencing (WES) of three affected members, we identified a novel heterozygous missense variant (c.1963C>A:p.Leu655Met) in the gene encoding myosin heavy chain 7 (MYH7). This gene is evolutionary conserved among different organisms. We identified MYH7 as a highly enriched myosin, compared to other types of myosin heavy chains, in skeletal and cardiac muscles. Furthermore, MYH7 was among a few classes of MYH in mouse heart that highly expresses from early embryonic to adult stages. In silico predictions showed an altered actin-myosin binding, resulting in weaker binding energy that can cause LVNC. Moreover, CRISPR/Cas9 mediated MYH7 knockout in zebrafish caused impaired cardiovascular development. Altogether, these findings provide the first evidence for involvement of p.Leu655Met missense variant in the incidence of LVNC, most probably through actin-myosin binding defects during ventricular wall morphogenesis.
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Affiliation(s)
- Mahdi Hesaraki
- Department of Developmental Biology, School of Basic Sciences and Advanced Technologies in Biology, University of Science and Culture, Tehran, Iran
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Ugur Bora
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health, Izmir, Turkey
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Izmir, Turkey
| | - Sara Pahlavan
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Najmeh Salehi
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
- School of Biological Science, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
| | - Seyed Ahmad Mousavi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Maryam Barekat
- Department of Regenerative Medicine, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Seyed Javad Rasouli
- Department of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Hossein Baharvand
- Department of Developmental Biology, School of Basic Sciences and Advanced Technologies in Biology, University of Science and Culture, Tehran, Iran
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Gunes Ozhan
- Izmir Biomedicine and Genome Center (IBG), Dokuz Eylul University Health, Izmir, Turkey
- Izmir International Biomedicine and Genome Institute (IBG-Izmir), Dokuz Eylul University, Izmir, Turkey
- *Correspondence: Gunes Ozhan
| | - Mehdi Totonchi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
- School of Biological Science, Institute for Research in Fundamental Sciences (IPM), Tehran, Iran
- Mehdi Totonchi
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4
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Ding Y, Dvornikov AV, Ma X, Zhang H, Wang Y, Lowerison M, Packard RR, Wang L, Chen J, Zhang Y, Hsiai T, Lin X, Xu X. Haploinsufficiency of mechanistic target of rapamycin ameliorates bag3 cardiomyopathy in adult zebrafish. Dis Model Mech 2019; 12:dmm040154. [PMID: 31492659 PMCID: PMC6826022 DOI: 10.1242/dmm.040154] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 08/28/2019] [Indexed: 12/14/2022] Open
Abstract
The adult zebrafish is an emerging vertebrate model for studying human cardiomyopathies; however, whether the simple zebrafish heart can model different subtypes of cardiomyopathies, such as dilated cardiomyopathy (DCM), remains elusive. Here, we generated and characterized an inherited DCM model in adult zebrafish and used this model to search for therapeutic strategies. We employed transcription activator-like effector nuclease (TALEN) genome editing technology to generate frame-shift mutants for the zebrafish ortholog of human BCL2-associated athanogene 3 (BAG3), an established DCM-causative gene. As in mammals, the zebrafish bag3 homozygous mutant (bag3e2/e2 ) exhibited aberrant proteostasis, as indicated by impaired autophagy flux and elevated ubiquitinated protein aggregation. Through comprehensive phenotyping analysis of the mutant, we identified phenotypic traits that resembled DCM phenotypes in mammals, including cardiac chamber enlargement, reduced ejection fraction characterized by increased end-systolic volume/body weight (ESV/BW), and reduced contractile myofibril activation kinetics. Nonbiased transcriptome analysis identified the hyperactivation of the mechanistic target of rapamycin (mTOR) signaling in bag3e2/e2 mutant hearts. Further genetic studies showed that mtorxu015/+ , an mTOR haploinsufficiency mutant, repaired abnormal proteostasis, improved cardiac function and rescued the survival of the bag3e2/e2 mutant. This study established the bag3e2/e2 mutant as a DCM model in adult zebrafish and suggested mtor as a candidate therapeutic target gene for BAG3 cardiomyopathy.
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Affiliation(s)
- Yonghe Ding
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Alexey V Dvornikov
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Xiao Ma
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Center for Clinical and Translational Science, Mayo Clinic, Rochester, MN 55905, USA
- Mayo Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN 55905, USA
| | - Hong Zhang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Clinical Center for Gene Diagnosis and Therapy, the Second Xiangya Hospital of Central South University, Changsha, China 410011
| | - Yong Wang
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Institute of Life Science, Beijing University of Chinese Medicine, Beijing, China 100029
| | | | - Rene R Packard
- School of Medicine, University of California Los Angeles, Los Angeles, CA 90073, USA
| | - Lei Wang
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Jun Chen
- Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN 55905, USA
| | - Yuji Zhang
- Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Tzung Hsiai
- School of Medicine, University of California Los Angeles, Los Angeles, CA 90073, USA
| | - Xueying Lin
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Xiaolei Xu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN 55905, USA
- Center for Clinical and Translational Science, Mayo Clinic, Rochester, MN 55905, USA
- Mayo Graduate School of Biomedical Sciences, Mayo Clinic, Rochester, MN 55905, USA
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5
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Sewanan LR, Schwan J, Kluger J, Park J, Jacoby DL, Qyang Y, Campbell SG. Extracellular Matrix From Hypertrophic Myocardium Provokes Impaired Twitch Dynamics in Healthy Cardiomyocytes. JACC Basic Transl Sci 2019; 4:495-505. [PMID: 31468004 PMCID: PMC6712054 DOI: 10.1016/j.jacbts.2019.03.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/11/2019] [Accepted: 03/13/2019] [Indexed: 12/16/2022]
Abstract
The goal of this study was to examine the effects of diseased extracellular matrix on the behavior of healthy heart cells. Myocardium was harvested from a genetically engineered miniature pig carrying the hypertrophic cardiomyopathy mutation MYH7 R403Q and from a wild-type littermate. Engineered heart tissues were created by seeding healthy human induced pluripotent stem cell–derived cardiomyocytes onto thin strips of decellularized porcine myocardium. Engineered heart tissues made from the extracellular matrix of hypertrophic cardiomyopathy hearts exhibit increased stiffness, impaired relaxation, and increased force development. This suggests that diseased extracellular matrix can provoke abnormal contractile behavior in otherwise healthy cardiomyocytes.
Hypertrophic cardiomyopathy (HCM) is often caused by single sarcomeric gene mutations that affect muscle contraction. Pharmacological correction of mutation effects prevents but does not reverse disease in mouse models. Suspecting that diseased extracellular matrix is to blame, we obtained myocardium from a miniature swine model of HCM, decellularized thin slices of the tissue, and re-seeded them with healthy human induced pluripotent stem cell–derived cardiomyocytes. Compared with cardiomyocytes grown on healthy extracellular matrix, those grown on the diseased matrix exhibited prolonged contractions and poor relaxation. This outcome suggests that extracellular matrix abnormalities must be addressed in therapies targeting established HCM.
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Key Words
- CM, cardiomyocyte
- ECM, extracellular matrix
- EHT, engineered heart tissue
- H&E, hematoxylin and eosin
- HCM, hypertrophic cardiomyopathy
- MTR, Masson trichrome
- MUT, minipig carrying MYH7 R403Q mutation
- MYH7 mutation
- RT50, time from peak tension to 50% relaxation
- SR, Sirius red
- TTP, time to peak tension
- WT, wild-type
- cDNA, complementary deoxyribonucleic acid
- diastolic dysfunction
- engineered heart tissue
- fibrosis
- hypertrophic cardiomyopathy
- iPSC, induced pluripotent stem cell
- iPSC-derived cardiomyocyte
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Affiliation(s)
- Lorenzo R Sewanan
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Jonas Schwan
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Jonathan Kluger
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Jinkyu Park
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut.,Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, Connecticut
| | - Daniel L Jacoby
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut
| | - Yibing Qyang
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, Connecticut.,Yale Stem Cell Center, Yale University, New Haven, Connecticut.,Department of Pathology, Yale University, New Haven, Connecticut.,Vascular Biology and Therapeutics Program, Yale School of Medicine, New Haven, Connecticut
| | - Stuart G Campbell
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut.,Department of Cellular and Molecular Physiology, Yale School of Medicine, New Haven, Connecticut
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6
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Heitner SB, Jacoby D, Lester SJ, Owens A, Wang A, Zhang D, Lambing J, Lee J, Semigran M, Sehnert AJ. Mavacamten Treatment for Obstructive Hypertrophic Cardiomyopathy: A Clinical Trial. Ann Intern Med 2019; 170:741-748. [PMID: 31035291 DOI: 10.7326/m18-3016] [Citation(s) in RCA: 169] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Mavacamten, an orally administered, small-molecule modulator of cardiac myosin, targets underlying biomechanical abnormalities in obstructive hypertrophic cardiomyopathy (oHCM). OBJECTIVE To characterize the effect of mavacamten on left ventricular outflow tract (LVOT) gradient. DESIGN Open-label, nonrandomized, phase 2 trial. (ClinicalTrials.gov: NCT02842242). SETTING 5 academic centers. PARTICIPANTS 21 symptomatic patients with oHCM. INTERVENTION Patients in cohort A received mavacamten, 10 to 20 mg/d, without background medications. Those in cohort B received mavacamten, 2 to 5 mg/d, with β-blockers allowed. MEASUREMENTS The primary end point was change in postexercise LVOT gradient at 12 weeks. Secondary end points included changes in peak oxygen consumption (pVO2), resting and Valsalva LVOT gradients, left ventricular ejection fraction (LVEF), and numerical rating scale dyspnea score. RESULTS In cohort A, mavacamten reduced mean postexercise LVOT gradient from 103 mm Hg (SD, 50) at baseline to 19 mm Hg (SD, 13) at 12 weeks (mean change, -89.5 mm Hg [95% CI, -138.3 to -40.7 mm Hg]; P = 0.008). Resting LVEF was also reduced (mean change, -15% [CI, -23% to -6%]). Peak VO2 increased by a mean of 3.5 mL/kg/min (CI, 1.2 to 5.9 mL/kg/min). In cohort B, the mean postexercise LVOT gradient decreased from 86 mm Hg (SD, 43) to 64 mm Hg (SD, 26) (mean change, -25.0 mm Hg [CI, -47.1 to -3.0 mm Hg]; P = 0.020), and mean change in resting LVEF was -6% (CI, -10% to -1%). Peak VO2 increased by a mean of 1.7 mL/kg/min (SD, 2.3) (CI, 0.03 to 3.3 mL/kg/min). Dyspnea scores improved in both cohorts. Mavacamten was well tolerated, with mostly mild (80%), moderate (19%), and unrelated (79%) adverse events. The most common adverse events definitely or possibly related to mavacamten were decreased LVEF at higher plasma concentrations and atrial fibrillation. LIMITATION Small size; open-label design. CONCLUSION Mavacamten can reduce LVOT obstruction and improve exercise capacity and symptoms in patients with oHCM. PRIMARY FUNDING SOURCE MyoKardia.
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Affiliation(s)
| | - Daniel Jacoby
- Yale New Haven Hospital, New Haven, Connecticut (D.J.)
| | | | - Anjali Owens
- Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (A.O.)
| | - Andrew Wang
- Duke University Medical Center, Durham, North Carolina (A.W.)
| | - David Zhang
- MyoKardia, South San Francisco, California (D.Z., J.L., J.L., M.S., A.J.S.)
| | - Joseph Lambing
- MyoKardia, South San Francisco, California (D.Z., J.L., J.L., M.S., A.J.S.)
| | - June Lee
- MyoKardia, South San Francisco, California (D.Z., J.L., J.L., M.S., A.J.S.)
| | - Marc Semigran
- MyoKardia, South San Francisco, California (D.Z., J.L., J.L., M.S., A.J.S.)
| | - Amy J Sehnert
- MyoKardia, South San Francisco, California (D.Z., J.L., J.L., M.S., A.J.S.)
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7
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Cohn R, Thakar K, Lowe A, Ladha FA, Pettinato AM, Romano R, Meredith E, Chen YS, Atamanuk K, Huey BD, Hinson JT. A Contraction Stress Model of Hypertrophic Cardiomyopathy due to Sarcomere Mutations. Stem Cell Reports 2018; 12:71-83. [PMID: 30554920 PMCID: PMC6335568 DOI: 10.1016/j.stemcr.2018.11.015] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 11/18/2018] [Accepted: 11/19/2018] [Indexed: 12/14/2022] Open
Abstract
Thick-filament sarcomere mutations are a common cause of hypertrophic cardiomyopathy (HCM), a disorder of heart muscle thickening associated with sudden cardiac death and heart failure, with unclear mechanisms. We engineered four isogenic induced pluripotent stem cell (iPSC) models of β-myosin heavy chain and myosin-binding protein C3 mutations, and studied iPSC-derived cardiomyocytes in cardiac microtissue assays that resemble cardiac architecture and biomechanics. All HCM mutations resulted in hypercontractility with prolonged relaxation kinetics in proportion to mutation pathogenicity, but not changes in calcium handling. RNA sequencing and expression studies of HCM models identified p53 activation, oxidative stress, and cytotoxicity induced by metabolic stress that can be reversed by p53 genetic ablation. Our findings implicate hypercontractility as a direct consequence of thick-filament mutations, irrespective of mutation localization, and the p53 pathway as a molecular marker of contraction stress and candidate therapeutic target for HCM patients.
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Affiliation(s)
- Rachel Cohn
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA
| | - Ketan Thakar
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA
| | - Andre Lowe
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA
| | - Feria A Ladha
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA; University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06032, USA
| | - Anthony M Pettinato
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA; University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06032, USA
| | - Robert Romano
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA; University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06032, USA
| | - Emily Meredith
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA; University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06032, USA
| | - Yu-Sheng Chen
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA
| | - Katherine Atamanuk
- Department of Biomedical Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - Bryan D Huey
- Department of Materials Science and Engineering, University of Connecticut, Storrs, CT 06269, USA
| | - J Travis Hinson
- The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, CT 06032, USA; University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06032, USA.
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8
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Greenberg MJ, Daily NJ, Wang A, Conway MK, Wakatsuki T. Genetic and Tissue Engineering Approaches to Modeling the Mechanics of Human Heart Failure for Drug Discovery. Front Cardiovasc Med 2018; 5:120. [PMID: 30283789 PMCID: PMC6156537 DOI: 10.3389/fcvm.2018.00120] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 08/13/2018] [Indexed: 12/14/2022] Open
Abstract
Heart failure is the leading cause of death in the western world and as such, there is a great need for new therapies. Heart failure has a variable presentation in patients and a complex etiology; however, it is fundamentally a condition that affects the mechanics of cardiac contraction, preventing the heart from generating sufficient cardiac output under normal operating pressures. One of the major issues hindering the development of new therapies has been difficulties in developing appropriate in vitro model systems of human heart failure that recapitulate the essential changes in cardiac mechanics seen in the disease. Recent advances in stem cell technologies, genetic engineering, and tissue engineering have the potential to revolutionize our ability to model and study heart failure in vitro. Here, we review how these technologies are being applied to develop personalized models of heart failure and discover novel therapeutics.
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Affiliation(s)
- Michael J Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States
| | | | - Ann Wang
- InvivoSciences Inc., Madison, WI, United States
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9
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Chung JH, Biesiadecki BJ, Ziolo MT, Davis JP, Janssen PML. Myofilament Calcium Sensitivity: Role in Regulation of In vivo Cardiac Contraction and Relaxation. Front Physiol 2016; 7:562. [PMID: 28018228 PMCID: PMC5159616 DOI: 10.3389/fphys.2016.00562] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/07/2016] [Indexed: 11/13/2022] Open
Abstract
Myofilament calcium sensitivity is an often-used indicator of cardiac muscle function, often assessed in disease states such as hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM). While assessment of calcium sensitivity provides important insights into the mechanical force-generating capability of a muscle at steady-state, the dynamic behavior of the muscle cannot be sufficiently assessed with a force-pCa curve alone. The equilibrium dissociation constant (Kd) of the force-pCa curve depends on the ratio of the apparent calcium association rate constant (kon) and apparent calcium dissociation rate constant (koff) of calcium on TnC and as a stand-alone parameter cannot provide an accurate description of the dynamic contraction and relaxation behavior without the additional quantification of kon or koff, or actually measuring dynamic twitch kinetic parameters in an intact muscle. In this review, we examine the effect of length, frequency, and beta-adrenergic stimulation on myofilament calcium sensitivity and dynamic contraction in the myocardium, the effect of membrane permeabilization/mechanical- or chemical skinning on calcium sensitivity, and the dynamic consequences of various myofilament protein mutations with potential implications in contractile and relaxation behavior.
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Affiliation(s)
- Jae-Hoon Chung
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Medical Scientist Training Program and Biomedical Sciences Graduate Program, The Ohio State University Wexner Medical CenterColumbus, OH, USA
| | - Brandon J Biesiadecki
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA
| | - Mark T Ziolo
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA
| | - Jonathan P Davis
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA
| | - Paul M L Janssen
- Department of Physiology and Cell Biology, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical CenterColumbus, OH, USA; Department of Internal Medicine, The Ohio State University Wexner Medical CenterColumbus, OH, USA
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10
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Viola HM, Johnstone VPA, Cserne Szappanos H, Richman TR, Tsoutsman T, Filipovska A, Semsarian C, Seidman JG, Seidman CE, Hool LC. The Role of the L-Type Ca 2+ Channel in Altered Metabolic Activity in a Murine Model of Hypertrophic Cardiomyopathy. JACC Basic Transl Sci 2016; 1:61-72. [PMID: 30167506 PMCID: PMC6113168 DOI: 10.1016/j.jacbts.2015.12.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 12/31/2015] [Indexed: 01/08/2023]
Abstract
Heterozygous mice (αMHC403/+) expressing the human disease-causing mutation Arg403Gln exhibit cardinal features of hypertrophic cardiomyopathy (HCM) including hypertrophy, myocyte disarray, and increased myocardial fibrosis. Treatment of αMHC403/+mice with the L-type calcium channel (ICa-L) antagonist diltiazem has been shown to decrease left ventricular anterior wall thickness, cardiac myocyte hypertrophy, disarray, and fibrosis. However, the role of the ICa-L in the development of HCM is not known. In addition to maintaining cardiac excitation and contraction in myocytes, the ICa-L also regulates mitochondrial function through transmission of movement of ICa-L via cytoskeletal proteins to mitochondrial voltage-dependent anion channel. Here, the authors investigated the role of ICa-L in regulating mitochondrial function in αMHC403/+mice. Whole-cell patch clamp studies showed that ICa-L current inactivation kinetics were significantly increased in αMHC403/+cardiac myocytes, but that current density and channel expression were similar to wild-type cardiac myocytes. Activation of ICa-L caused a significantly greater increase in mitochondrial membrane potential and metabolic activity in αMHC403/+. These increases were attenuated with ICa-L antagonists and following F-actin or β-tubulin depolymerization. The authors observed increased levels of fibroblast growth factor-21 in αMHC403/+mice, and altered mitochondrial DNA copy number consistent with altered mitochondrial activity and the development of cardiomyopathy. These studies suggest that the Arg403Gln mutation leads to altered functional communication between ICa-L and mitochondria that is associated with increased metabolic activity, which may contribute to the development of cardiomyopathy. ICa-L antagonists may be effective in reducing the cardiomyopathy in HCM by altering metabolic activity. Heterozygous mice (αMHC403/+) expressing the human hypertrophic cardiomyopathy (HCM) disease causing mutation Arg403Gln exhibit cardinal features of HCM. This study investigated the role of L-type Ca2+ channel (ICa-L) in regulating mitochondrial function in Arg403Gln (αMHC403/+) mice. Activation of ICa-L in αMHC403/+mice caused a significantly greater increase in mitochondrial membrane potential and metabolic activity when compared to wild-type mice. Increases in mitochondrial membrane potential and metabolic activity were attenuated with ICa-L antagonists and when F-actin or β-tubulin were depolymerized. ICa-L antagonists may be effective in reducing the cardiomyopathy in HCM by altering metabolic activity.
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Affiliation(s)
- Helena M Viola
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Victoria P A Johnstone
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Henrietta Cserne Szappanos
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia
| | - Tara R Richman
- The Harry Perkins Institute for Medical Research, The University of Western Australia, Crawley, Australia
| | - Tatiana Tsoutsman
- Agnes Ginges Centre for Molecular Cardiology, Centenary Institute, Sydney, Australia.,Sydney Medical School, University of Sydney, Australia
| | - Aleksandra Filipovska
- The Harry Perkins Institute for Medical Research, The University of Western Australia, Crawley, Australia
| | - Christopher Semsarian
- Agnes Ginges Centre for Molecular Cardiology, Centenary Institute, Sydney, Australia.,Sydney Medical School, University of Sydney, Australia.,Department of Cardiology, Royal Prince Alfred Hospital, Sydney, Australia
| | | | | | - Livia C Hool
- School of Anatomy, Physiology and Human Biology, The University of Western Australia, Crawley, Australia.,Victor Chang Cardiac Research Institute, Sydney, Australia
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11
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Cannon L, Yu ZY, Marciniec T, Waardenberg AJ, Iismaa SE, Nikolova-Krstevski V, Neist E, Ohanian M, Qiu MR, Rainer S, Harvey RP, Feneley MP, Graham RM, Fatkin D. Irreversible triggers for hypertrophic cardiomyopathy are established in the early postnatal period. J Am Coll Cardiol 2015; 65:560-9. [PMID: 25677315 DOI: 10.1016/j.jacc.2014.10.069] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Revised: 10/09/2014] [Accepted: 10/28/2014] [Indexed: 12/12/2022]
Abstract
BACKGROUND Hypertrophic cardiomyopathy (HCM) is caused by mutations in sarcomere protein genes, and left ventricular hypertrophy (LVH) develops as an adaptive response to sarcomere dysfunction. It remains unclear whether persistent expression of the mutant gene is required for LVH or whether early gene expression acts as an immutable inductive trigger. OBJECTIVES The aim of this study was to use a regulatable murine model of HCM to study the reversibility of pathological LVH. METHODS The authors generated a double-transgenic mouse model, tTAxαMHCR403Q, in which expression of the HCM-causing Arg403Gln mutation in the α-myosin heavy chain (MHC) gene is inhibited by doxycycline administration. Cardiac structure and function were evaluated in groups of mice that received doxycycline for varying periods from 0 to 40 weeks of age. RESULTS Untreated tTAxαMHCR403Q mice showed increased left ventricular (LV) mass, contractile dysfunction, myofibrillar disarray, and fibrosis. In contrast, mice treated with doxycycline from conception to 6 weeks had markedly less LVH and fibrosis at 40 weeks. Transgene inhibition from 6 weeks reduced fibrosis but did not prevent LVH or functional changes. There were no differences in LV parameters at 40 weeks between mice with transgene inhibition from 20 weeks and mice with continuous transgene expression. CONCLUSIONS These findings highlight the critical role of the early postnatal period in HCM pathogenesis and suggest that mutant sarcomeres manifest irreversible cardiomyocyte defects that induce LVH. In HCM, mutation-silencing therapies are likely to be ineffective for hypertrophy regression and would have to be administered very early in life to prevent hypertrophy development.
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Affiliation(s)
- Leah Cannon
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Ze-Yan Yu
- Cardiac Physiology and Transplantation Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Tadeusz Marciniec
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Ashley J Waardenberg
- Cardiac Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Siiri E Iismaa
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia; Faculty of Medicine, University of New South Wales, Kensington, Australia
| | - Vesna Nikolova-Krstevski
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia; Faculty of Medicine, University of New South Wales, Kensington, Australia
| | - Elysia Neist
- Cardiac Physiology and Transplantation Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Monique Ohanian
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia
| | - Min Ru Qiu
- Anatomical Pathology Department, St. Vincent's Hospital, Darlinghurst, Australia
| | - Stephen Rainer
- Anatomical Pathology Department, St. Vincent's Hospital, Darlinghurst, Australia
| | - Richard P Harvey
- Cardiac Developmental and Stem Cell Biology Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia; Faculty of Medicine, University of New South Wales, Kensington, Australia; School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, Australia
| | - Michael P Feneley
- Cardiac Physiology and Transplantation Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia; Faculty of Medicine, University of New South Wales, Kensington, Australia; Cardiology Department, St. Vincent's Hospital, Darlinghurst, Australia
| | - Robert M Graham
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia; Faculty of Medicine, University of New South Wales, Kensington, Australia; School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, Australia; Cardiology Department, St. Vincent's Hospital, Darlinghurst, Australia.
| | - Diane Fatkin
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, Australia; Faculty of Medicine, University of New South Wales, Kensington, Australia; Cardiology Department, St. Vincent's Hospital, Darlinghurst, Australia.
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12
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Spudich JA. Hypertrophic and dilated cardiomyopathy: four decades of basic research on muscle lead to potential therapeutic approaches to these devastating genetic diseases. Biophys J 2014; 106:1236-49. [PMID: 24655499 PMCID: PMC3985504 DOI: 10.1016/j.bpj.2014.02.011] [Citation(s) in RCA: 195] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 01/30/2014] [Accepted: 02/04/2014] [Indexed: 01/10/2023] Open
Abstract
With the advent of technologies to obtain the complete sequence of the human genome in a cost-effective manner, this decade and those to come will see an exponential increase in our understanding of the underlying genetics that lead to human disease. And where we have a deep understanding of the biochemical and biophysical basis of the machineries and pathways involved in those genetic changes, there are great hopes for the development of modern therapeutics that specifically target the actual machinery and pathways altered by individual mutations. Prime examples of such a genetic disease are those classes of hypertrophic and dilated cardiomyopathy that result from single amino-acid substitutions in one of several of the proteins that make up the cardiac sarcomere or from the truncation of myosin binding protein C. Hypertrophic cardiomyopathy alone affects ∼1 in 500 individuals, and it is the leading cause of sudden cardiac death in young adults. Here I describe approaches to understand the molecular basis of the alterations in power output that result from these mutations. Small molecules binding to the mutant sarcomeric protein complex should be able to mitigate the effects of hypertrophic and dilated cardiomyopathy mutations at their sources, leading to possible new therapeutic approaches for these genetic diseases.
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Affiliation(s)
- James A Spudich
- Department of Biochemistry, Stanford University School of Medicine, Stanford, California.
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13
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Fatkin D, Seidman CE, Seidman JG. Genetics and disease of ventricular muscle. Cold Spring Harb Perspect Med 2014; 4:a021063. [PMID: 24384818 DOI: 10.1101/cshperspect.a021063] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cardiomyopathies are a heterogeneous group of heart muscle diseases associated with heart failure, arrhythmias, and death. Genetic variation has a critical role in the pathogenesis of cardiomyopathies, and numerous single-gene mutations have been associated with distinctive cardiomyopathy phenotypes. Contemporaneously with these discoveries, there has been enormous growth of genome-wide sequencing studies in large populations, data that show extensive genomic variation within every individual. The considerable allelic diversity in cardiomyopathy genes and in genes predicted to impact clinical expression of disease mutations indicates the need for a more nuanced interpretation of single-gene mutation in cardiomyopathies. These findings highlight the need to find new ways to interpret the functional significance of suites of genetic variants, as well as the need for new disease models that take global genetic variant burdens, epigenetic factors, and cardiac environmental factors into account.
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Affiliation(s)
- Diane Fatkin
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales 2010, Australia
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14
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Abstract
PURPOSE OF REVIEW Sudden cardiac death (SCD) affects a significant percentage of young individuals. SCDs are due to genetic heart disorders, such as cardiomyopathies and channelopathies. In the present review, we will describe the recent advancements in understanding the genetic and molecular basis of hereditary cardiac diseases. RECENT FINDINGS Considerable progress has been made in identification of new genes associated with monogenic familial arrhythmogenic syndromes, giving the opportunity to delineate their molecular pathogenesis and identify potential targets for therapeutic intervention. Research discoveries and rapidly dropping costs of DNA sequencing technologies have resulted in availability of genetic testing panels. SUMMARY Advances in genetic sequencing technology are expected to significantly impact the clinical practice in the near future. Genetic testing represents a powerful tool for cause determination of arrhythmogenic cardiac diseases, efficient screening of family members, possible risk stratification and treatment choices. However, specific expertise is required for rational ordering and correct interpretation of the genetic screening results.
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15
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Teekakirikul P, Padera RF, Seidman JG, Seidman CE. Hypertrophic cardiomyopathy: translating cellular cross talk into therapeutics. ACTA ACUST UNITED AC 2013; 199:417-21. [PMID: 23109667 PMCID: PMC3483129 DOI: 10.1083/jcb.201207033] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypertrophic cardiomyopathy (HCM) is a common inherited heart disease with serious adverse outcomes, including heart failure, arrhythmias, and sudden cardiac death. The discovery that mutations in sarcomere protein genes cause HCM has enabled the development of mouse models that recapitulate clinical manifestations of disease. Studies in these models have provided unexpected insights into the biophysical and biochemical properties of mutated contractile proteins and may help to improve clinical diagnosis and management of patients with HCM.
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