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d’Apolito M, Santoro F, Ranaldi A, Ragnatela I, Colia AL, Cannito S, Margaglione A, D’Arienzo G, D’Andrea G, Pellegrino P, Santacroce R, Brunetti ND, Margaglione M. Investigation of a Large Kindred Reveals Cardiac Calsequestrin ( CASQ2) as a Cause of Brugada Syndrome. Genes (Basel) 2024; 15:822. [PMID: 39062601 PMCID: PMC11275647 DOI: 10.3390/genes15070822] [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: 05/31/2024] [Revised: 06/17/2024] [Accepted: 06/19/2024] [Indexed: 07/28/2024] Open
Abstract
BACKGROUND Brugada syndrome (BrS) is an inherited primary channelopathy syndrome associated with the risk of ventricular fibrillation (VF) and sudden cardiac death in a structurally normal heart. AIM OF THE STUDY The aim of this study was to clinically and genetically evaluate a large family with severe autosomal dominant Brugada syndrome. METHODS Clinical and genetic studies were performed. Genetic analysis was conducted with NGS technologies (WES) using the Illumina instrument. According to the standard procedure, variants found by WES were confirmed in all available families by Sanger sequencing. The effect of the variants was studied by using in silico prediction of pathogenicity. RESULTS The proband was a 52-year-old man who was admitted to the emergency department for syncope at rest. WES of the index case identified a heterozygous VUS CASQ2, c.532T>C, p.(Tyr178His). We studied the segregation of the variation in all pedigree members. All the patients were heterozygous for the variation CASQ2 p.(Tyr178His), whereas the remaining healthy individuals in the family were homozygous for the normal allele. Structural analysis of CASQ2 p.(Tyr178His) was performed and revealed an important effect of the missense variation on monomer stability. The CASQ2 Tyr180 residue is located inside the sarcoplasmic reticulum (SR) junctional face membrane interaction domain and is predicted to disrupt filamentation. CONCLUSIONS Our data suggest that the p.Tyr178His substitution is associated with BrS in the family investigated, affecting the stability of the protein, disrupting filamentation at the interdimer interface, and affecting the subsequent formation of tetramers and polymers that contain calcium-binding sites.
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Affiliation(s)
- Maria d’Apolito
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
| | - Francesco Santoro
- Cardiology Unit, Department of Medical and Surgery Sciences, University of Foggia, 71122 Foggia, Italy
| | - Alessandra Ranaldi
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
| | - Ilaria Ragnatela
- Cardiology Unit, Department of Medical and Surgery Sciences, University of Foggia, 71122 Foggia, Italy
| | - Anna Laura Colia
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
| | - Sara Cannito
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
| | - Alessandra Margaglione
- Cardiology Unit, Department of Medical and Surgery Sciences, University of Foggia, 71122 Foggia, Italy
| | - Girolamo D’Arienzo
- Cardiology Unit, Department of Medical and Surgery Sciences, University of Foggia, 71122 Foggia, Italy
| | - Giovanna D’Andrea
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
| | - PierLuigi Pellegrino
- Cardiology Unit, Department of Medical and Surgery Sciences, University of Foggia, 71122 Foggia, Italy
| | - Rosa Santacroce
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
| | - Natale Daniele Brunetti
- Cardiology Unit, Department of Medical and Surgery Sciences, University of Foggia, 71122 Foggia, Italy
| | - Maurizio Margaglione
- Medical Genetics, Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy; (A.R.); (A.L.C.)
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Siu A, Tandanu E, Ma B, Osas EE, Liu H, Liu T, Chou OHI, Huang H, Tse G. Precision medicine in catecholaminergic polymorphic ventricular tachycardia: Recent advances toward personalized care. Ann Pediatr Cardiol 2023; 16:431-446. [PMID: 38817258 PMCID: PMC11135882 DOI: 10.4103/apc.apc_96_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 12/12/2023] [Accepted: 01/14/2024] [Indexed: 06/01/2024] Open
Abstract
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare inherited cardiac ion channelopathy where the initial disease presentation is during childhood or adolescent stages, leading to increased risks of sudden cardiac death. Despite advances in medical science and technology, several gaps remain in the understanding of the molecular mechanisms, risk prediction, and therapeutic management of patients with CPVT. Recent studies have identified and validated seven sets of genes responsible for various CPVT phenotypes, including RyR2, CASQ-2, TRDN, CALM1, 2, and 3, and TECRL, providing novel insights into the molecular mechanisms. However, more data on atypical CPVT genotypes are required to investigate the underlying mechanisms further. The complexities of the underlying genetics contribute to challenges in risk stratification as well as the uncertainty surrounding nongenetic modifiers. Therapeutically, although medical management involving beta-blockers and flecainide, or insertion of an implantable cardioverter defibrillator remains the mainstay of treatment, animal and stem cell studies on gene therapy for CPVT have shown promising results. However, its clinical applicability remains unclear. Current gene therapy studies have primarily focused on the RyR2 and CASQ-2 variants, which constitute 75% of all CPVT cases. Alternative approaches that target a broader population, such as CaMKII inhibition, could be more feasible for clinical implementation. Together, this review provides an update on recent research on CPVT, highlighting the need for further investigation of the molecular mechanisms, risk stratification, and therapeutic management of this potentially lethal condition.
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Affiliation(s)
- Anthony Siu
- Cardiac Electrophysiology Unit, Cardiovascular Analytics Group, Powerhealth Research Institute, Hong Kong, China
- GKT School of Medical Education, King’s College London, London, United Kingdom
| | - Edelyne Tandanu
- GKT School of Medical Education, King’s College London, London, United Kingdom
| | - Brian Ma
- Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | | | - Haipeng Liu
- Research Centre for Intelligent Healthcare, Coventry University, Coventry, United Kingdom
| | - Tong Liu
- Department of Cardiology, Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China
| | - Oscar Hou In Chou
- Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Helen Huang
- University of Medicine and Health Science, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Gary Tse
- Department of Cardiology, Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China
- Kent and Medway Medical School, University of Kent, Canterbury, United Kingdom
- School of Nursing and Health Studies, Hong Kong Metropolitan University, Hong Kong, China
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Magyar ZÉ, Bauer J, Bauerová-Hlinková V, Jóna I, Gaburjakova J, Gaburjakova M, Almássy J. Eu 3+ detects two functionally distinct luminal Ca 2+ binding sites in ryanodine receptors. Biophys J 2023; 122:3516-3531. [PMID: 37533257 PMCID: PMC10502479 DOI: 10.1016/j.bpj.2023.07.029] [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: 02/23/2023] [Revised: 06/26/2023] [Accepted: 07/31/2023] [Indexed: 08/04/2023] Open
Abstract
Ryanodine receptors (RyRs) are Ca2+ release channels, gated by Ca2+ in the cytosol and the sarcoplasmic reticulum lumen. Their regulation is impaired in certain cardiac and muscle diseases. Although a lot of data is available on the luminal Ca2+ regulation of RyR, its interpretation is complicated by the possibility that the divalent ions used to probe the luminal binding sites may contaminate the cytoplasmic sites by crossing the channel pore. In this study, we used Eu3+, an impermeable agonist of Ca2+ binding sites, as a probe to avoid this complication and to gain more specific information about the function of the luminal Ca2+ sensor. Single-channel currents were measured from skeletal muscle and cardiac RyRs (RyR1 and RyR2) using the lipid bilayer technique. We show that RyR2 is activated by the luminal addition of Ca2+, whereas RyR1 is inhibited. These results were qualitatively reproducible using Eu3+. The luminal regulation of RyR1 carrying a mutation associated with malignant hyperthermia was not different from that of the wild-type. RyR1 inhibition by Eu3+ was extremely voltage dependent, whereas RyR2 activation did not depend on the membrane potential. These results suggest that the RyR1 inhibition site is in the membrane's electric field (channel pore), whereas the RyR2 activation site is outside. Using in silico analysis and previous results, we predicted putative Ca2+ binding site sequences. We propose that RyR2 bears an activation site, which is missing in RyR1, but both isoforms share the same inhibitory Ca2+ binding site near the channel gate.
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Affiliation(s)
- Zsuzsanna É Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Jacob Bauer
- Institute of Molecular Biology, Slovak Academy of Sciences, Bratislava, Slovakia
| | | | - István Jóna
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Jana Gaburjakova
- Institute of Molecular Physiology and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Marta Gaburjakova
- Institute of Molecular Physiology and Genetics, Centre of Biosciences, Slovak Academy of Sciences, Bratislava, Slovakia
| | - János Almássy
- Department of Physiology, Semmelweis University, Budapest, Hungary.
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Transcriptomic Profile of Genes Regulating the Structural Organization of Porcine Atrial Cardiomyocytes during Primary In Vitro Culture. Genes (Basel) 2022; 13:genes13071205. [PMID: 35885988 PMCID: PMC9319992 DOI: 10.3390/genes13071205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/02/2022] [Accepted: 07/04/2022] [Indexed: 02/04/2023] Open
Abstract
Numerous cardiovascular diseases (CVD) eventually lead to severe myocardial dysfunction, which is the most common cause of death worldwide. A better understanding of underlying molecular mechanisms of cardiovascular pathologies seems to be crucial to develop effective therapeutic options. Therefore, a worthwhile endeavor is a detailed molecular characterization of cells extracted from the myocardium. A transcriptomic profile of atrial cardiomyocytes during long-term primary cell culture revealed the expression patterns depending on the duration of the culture and the heart segment of origin (right atrial appendage and right atrium). Differentially expressed genes (DEGs) were classified as involved in ontological groups such as: “cellular component assembly”, “cellular component organization”, “cellular component biogenesis”, and “cytoskeleton organization”. Transcriptomic profiling allowed us to indicate the increased expression of COL5A2, COL8A1, and COL12A1, encoding different collagen subunits, pivotal in cardiac extracellular matrix (ECM) structure. Conversely, genes important for cellular architecture, such as ABLIM1, TMOD1, XIRP1, and PHACTR1, were downregulated during in vitro culture. The culture conditions may create a favorable environment for reconstruction of the ECM structures, whereas they may be suboptimal for expression of some pivotal transcripts responsible for the formation of intracellular structures.
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Engel MA, Wörmann YR, Kaestner H, Schüler C. An Optogenetic Arrhythmia Model—Insertion of Several Catecholaminergic Polymorphic Ventricular Tachycardia Mutations Into Caenorhabditis elegans UNC-68 Disturbs Calstabin-Mediated Stabilization of the Ryanodine Receptor Homolog. Front Physiol 2022; 13:691829. [PMID: 35399287 PMCID: PMC8990320 DOI: 10.3389/fphys.2022.691829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 02/15/2022] [Indexed: 11/14/2022] Open
Abstract
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited disturbance of the heart rhythm (arrhythmia) that is induced by stress or that occurs during exercise. Most mutations that have been linked to CPVT are found in two genes, i.e., ryanodine receptor 2 (RyR2) and calsequestrin 2 (CASQ2), two proteins fundamentally involved in the regulation of intracellular Ca2+ in cardiac myocytes. We inserted six CPVT-causing mutations via clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 into unc-68 and csq-1, the Caenorhabditis elegans homologs of RyR and CASQ, respectively. We characterized those mutations via video-microscopy, electrophysiology, and calcium imaging in our previously established optogenetic arrhythmia model. In this study, we additionally enabled high(er) throughput recordings of intact animals by combining optogenetic stimulation with a microfluidic chip system. Whereas only minor/no pump deficiency of the pharynx was observed at baseline, three mutations of UNC-68 (S2378L, P2460S, Q4623R; RyR2-S2246L, -P2328S, -Q4201R) reduced the ability of the organ to follow 4 Hz optogenetic stimulation. One mutation (Q4623R) was accompanied by a strong reduction of maximal pump rate. In addition, S2378L and Q4623R evoked an altered calcium handling during optogenetic stimulation. The 1,4-benzothiazepine S107, which is suggested to stabilize RyR2 channels by enhancing the binding of calstabin2, reversed the reduction of pumping ability in a mutation-specific fashion. However, this depends on the presence of FKB-2, a C. elegans calstabin2 homolog, indicating the involvement of calstabin2 in the disease-causing mechanisms of the respective mutations. In conclusion, we showed for three CPVT-like mutations in C. elegans RyR a reduced pumping ability upon light stimulation, i.e., an arrhythmia-like phenotype, that can be reversed in two cases by the benzothiazepine S107 and that depends on stabilization via FKB-2. The genetically amenable nematode in combination with optogenetics and high(er) throughput recordings is a promising straightforward system for the investigation of RyR mutations and the selection of mutation-specific drugs.
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Affiliation(s)
- Marcial Alexander Engel
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt, Germany
- Institute of Biophysical Chemistry, Goethe University Frankfurt, Frankfurt, Germany
| | - Yves René Wörmann
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt, Germany
- Institute of Biophysical Chemistry, Goethe University Frankfurt, Frankfurt, Germany
| | - Hanna Kaestner
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt, Germany
- Institute of Biophysical Chemistry, Goethe University Frankfurt, Frankfurt, Germany
| | - Christina Schüler
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Frankfurt, Germany
- Institute of Biophysical Chemistry, Goethe University Frankfurt, Frankfurt, Germany
- *Correspondence: Christina Schüler,
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Kim JH, Lee E, Yun J, Ryu HS, Kim HK, Ju YW, Kim K, Kim J, Moon H. Calsequestrin 2 overexpression in breast cancer increases tumorigenesis and metastasis by modulating the tumor microenvironment. Mol Oncol 2022; 16:466-484. [PMID: 34743414 PMCID: PMC8763655 DOI: 10.1002/1878-0261.13136] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 10/05/2021] [Accepted: 11/04/2021] [Indexed: 01/16/2023] Open
Abstract
The spatial tumor shape is determined by the complex interactions between tumor cells and their microenvironment. Here, we investigated the role of a newly identified breast cancer-related gene, calsequestrin 2 (CASQ2), in tumor-microenvironment interactions during tumor growth and metastasis. We analyzed gene expression and three-dimensional tumor shape data from the breast cancer dataset of The Cancer Genome Atlas (TCGA) and identified CASQ2 as a potential regulator of tumor-microenvironment interaction. In TCGA breast cancer cases containing information of three-dimensional tumor shapes, CASQ2 mRNA showed the highest correlation with the spatial tumor shapes. Furthermore, we investigated the expression pattern of CASQ2 in human breast cancer tissues. CASQ2 was not detected in breast cancer cell lines in vitro but was induced in the xenograft tumors and human breast cancer tissues. To evaluate the role of CASQ2, we established CASQ2-overexpressing breast cancer cell lines for in vitro and in vivo experiments. CASQ2 overexpression in breast cancer cells resulted in a more aggressive phenotype and altered epithelial-mesenchymal transition (EMT) markers in vitro. CASQ2 overexpression induced cancer-associated fibroblast characteristics along with increased hypoxia-inducible factor 1α (HIF1α) expression in stromal fibroblasts. CASQ2 overexpression accelerated tumorigenesis, induced collagen structure remodeling, and increased distant metastasis in vivo. CASQ2 conferred more metaplastic features to triple-negative breast cancer cells. Our data suggest that CASQ2 is a key regulator of breast cancer tumorigenesis and metastasis by modulating diverse aspects of tumor-microenvironment interactions.
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Affiliation(s)
- Ju Hee Kim
- Biomedical Research InstituteSeoul National University HospitalSouth Korea
| | - Eun‐Shin Lee
- Biomedical Research InstituteSeoul National University HospitalSouth Korea
- Department of PathologySeoul National University School of MedicineSouth Korea
| | - Jihui Yun
- Genomic Medicine InstituteMedical Research CenterSeoul National UniversityKorea
- Department of Biomedical SciencesSeoul National University College of MedicineKorea
| | - Han Suk Ryu
- Department of PathologySeoul National University HospitalSouth Korea
| | - Hong Kyu Kim
- Department of SurgerySeoul National University HospitalKorea
| | - Young Wook Ju
- Department of SurgerySeoul National University HospitalKorea
| | - Kwangsoo Kim
- Division of Clinical BioinformaticsSeoul National University HospitalKorea
| | - Jong‐Il Kim
- Genomic Medicine InstituteMedical Research CenterSeoul National UniversityKorea
- Department of Biomedical SciencesSeoul National University College of MedicineKorea
- Cancer Research InstituteSeoul National UniversityKorea
- Department of Biochemistry and Molecular BiologySeoul National University College of MedicineKorea
| | - Hyeong‐Gon Moon
- Department of SurgerySeoul National University HospitalKorea
- Cancer Research InstituteSeoul National UniversityKorea
- Department of SurgerySeoul National University College of MedicineSouth Korea
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In vivo identification and validation of novel potential predictors for human cardiovascular diseases. PLoS One 2021; 16:e0261572. [PMID: 34919578 PMCID: PMC8682894 DOI: 10.1371/journal.pone.0261572] [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] [Received: 07/26/2021] [Accepted: 12/03/2021] [Indexed: 12/30/2022] Open
Abstract
Genetics crucially contributes to cardiovascular diseases (CVDs), the global leading cause of death. Since the majority of CVDs can be prevented by early intervention there is a high demand for the identification of predictive causative genes. While genome wide association studies (GWAS) correlate genes and CVDs after diagnosis and provide a valuable resource for such causative candidate genes, often preferentially those with previously known or suspected function are addressed further. To tackle the unaddressed blind spot of understudied genes, we particularly focused on the validation of human heart phenotype-associated GWAS candidates with little or no apparent connection to cardiac function. Building on the conservation of basic heart function and underlying genetics from fish to human we combined CRISPR/Cas9 genome editing of the orthologs of human GWAS candidates in isogenic medaka with automated high-throughput heart rate analysis. Our functional analyses of understudied human candidates uncovered a prominent fraction of heart rate associated genes from adult human patients impacting on the heart rate in embryonic medaka already in the injected generation. Following this pipeline, we identified 16 GWAS candidates with potential diagnostic and predictive power for human CVDs.
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Cely-Ortiz A, Felice JI, Díaz-Zegarra LA, Valverde CA, Federico M, Palomeque J, Wehrens XHT, Kranias EG, Aiello EA, Lascano EC, Negroni JA, Mattiazzi A. Determinants of Ca2+ release restitution: Insights from genetically altered animals and mathematical modeling. J Gen Physiol 2021; 152:152125. [PMID: 32986800 PMCID: PMC7594441 DOI: 10.1085/jgp.201912512] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 07/27/2020] [Accepted: 08/21/2020] [Indexed: 01/07/2023] Open
Abstract
Each heartbeat is followed by a refractory period. Recovery from refractoriness is known as Ca2+ release restitution (CRR), and its alterations are potential triggers of Ca2+ arrhythmias. Although the control of CRR has been associated with SR Ca2+ load and RYR2 Ca2+ sensitivity, the relative role of some of the determinants of CRR remains largely undefined. An intriguing point, difficult to dissect and previously neglected, is the possible independent effect of SR Ca2+ content versus the velocity of SR Ca2+ refilling on CRR. To assess these interrogations, we used isolated myocytes with phospholamban (PLN) ablation (PLNKO), knock-in mice with pseudoconstitutive CaMKII phosphorylation of RYR2 S2814 (S2814D), S2814D crossed with PLNKO mice (SDKO), and a previously validated human cardiac myocyte model. Restitution of cytosolic Ca2+ (Fura-2 AM) and L-type calcium current (ICaL; patch-clamp) was evaluated with a two-pulse (S1/S2) protocol. CRR and ICaL restitution increased as a function of the (S2-S1) coupling interval, following an exponential curve. When SR Ca2+ load was increased by increasing extracellular [Ca2+] from 2.0 to 4.0 mM, CRR and ICaL restitution were enhanced, suggesting that ICaL restitution may contribute to the faster CRR observed at 4.0 mM [Ca2+]. In contrast, ICaL restitution did not differ among the different mouse models. For a given SR Ca2+ load, CRR was accelerated in S2814D myocytes versus WT, but not in PLNKO and SDKO myocytes versus WT and S2814D, respectively. The model mimics all experimental data. Moreover, when the PLN ablation-induced decrease in RYR2 expression was corrected, the model revealed that CRR was accelerated in PLNKO and SDKO versus WT and S2814D myocytes, consistent with the enhanced velocity of refilling, SR [Ca2+] recovery, and CRR. We speculate that refilling rate might enhance CRR independently of SR Ca2+ load.
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Affiliation(s)
- Alejandra Cely-Ortiz
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Juan I Felice
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Leandro A Díaz-Zegarra
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Carlos A Valverde
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Marilén Federico
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Julieta Palomeque
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Xander H T Wehrens
- Departments of Molecular Physiology and Biophysics, Medicine (in Cardiology), Neuroscience, Pediatrics, Center for Space Medicine, Baylor College of Medicine, Cardiovascular Research Institute, Houston, TX
| | - Evangelia G Kranias
- Department of Pharmacology, University of Cincinnati College of Medicine, Cincinnati, OH
| | - Ernesto A Aiello
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
| | - Elena C Lascano
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Favaloro, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Jorge A Negroni
- Instituto de Medicina Traslacional, Trasplante y Bioingeniería, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Favaloro, Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Alicia Mattiazzi
- Centro de Investigaciones Cardiovasculares, Centro Científico Tecnológico-La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina
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9
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Muslimova EF, Rebrova TY, Kondratieva DS, Afanasiev SA. Role of Phospholamban (PLN), Triadin (TRDN), and Junctin (ASPH) Genes in the Development of Myocardial Contractile Dysfunction. RUSS J GENET+ 2021. [DOI: 10.1134/s1022795421050069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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10
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Yang M, Yan J, Wu A, Zhao W, Qin J, Pogwizd SM, Wu X, Yuan S, Ai X. Alterations of housekeeping proteins in human aged and diseased hearts. Pflugers Arch 2021; 473:351-362. [PMID: 33638007 PMCID: PMC10468297 DOI: 10.1007/s00424-021-02538-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/20/2021] [Accepted: 02/04/2021] [Indexed: 01/10/2023]
Abstract
Pathological remodeling includes alterations of ion channel function and calcium homeostasis and ultimately cardiac maladaptive function during the process of disease development. Biochemical assays are important approaches for assessing protein abundance and post-translational modification of ion channels. Several housekeeping proteins are commonly used as internal controls to minimize loading variabilities in immunoblotting protein assays. Yet, emerging evidence suggests that some housekeeping proteins may be abnormally altered under certain pathological conditions. However, alterations of housekeeping proteins in aged and diseased human hearts remain unclear. In the current study, immunoblotting was applied to measure three commonly used housekeeping proteins (β-actin, calsequestrin, and GAPDH) in well-procured human right atria (RA) and left ventricles (LV) from diabetic, heart failure, and aged human organ donors. Linear regression analysis suggested that the amounts of linearly loaded total proteins and quantified intensity of total proteins from either Ponceau S (PS) blot-stained or Coomassie Blue (CB) gel-stained images were highly correlated. Thus, all immunoblotting data were normalized with quantitative CB or PS data to calibrate potential loading variabilities. In the human heart, β-actin was reduced in diabetic RA and LV, while GAPDH was altered in aged and diabetic RA but not LV. Calsequestrin, an important Ca2+ regulatory protein, was significantly changed in aged, diabetic, and ischemic failing hearts. Intriguingly, expression levels of all three proteins were unchanged in non-ischemic failing human LV. Overall, alterations of human housekeeping proteins are heart chamber specific and disease context dependent. The choice of immunoblotting loading controls should be carefully evaluated. Usage of CB or PS total protein analysis could be a viable alternative approach for some complicated pathological specimens.
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Affiliation(s)
- Mei Yang
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA
| | - Jiajie Yan
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA
| | - Aimee Wu
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA
| | - Weiwei Zhao
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA
| | - Jin Qin
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA
| | - Steven M Pogwizd
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Xin Wu
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA
| | - Shengtao Yuan
- Jiangsu Key Laboratory of Drug Screening, China Pharmaceutical University, No. 24, Tongjiaxiang, Nanjing, 210009, China.
| | - Xun Ai
- Department of Physiology and Biophysics, Rush University Medical Center, 1750 West Harrison St. 1255 Jelke South, Chicago, IL, 60612, USA.
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11
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Ng K, Titus EW, Lieve KV, Roston TM, Mazzanti A, Deiter FH, Denjoy I, Ingles J, Till J, Robyns T, Connors SP, Steinberg C, Abrams DJ, Pang B, Scheinman MM, Bos JM, Duffett SA, van der Werf C, Maltret A, Green MS, Rutberg J, Balaji S, Cadrin-Tourigny J, Orland KM, Knight LM, Brateng C, Wu J, Tang AS, Skanes AC, Manlucu J, Healey JS, January CT, Krahn AD, Collins KK, Maginot KR, Fischbach P, Etheridge SP, Eckhardt LL, Hamilton RM, Ackerman MJ, Noguer FRI, Semsarian C, Jura N, Leenhardt A, Gollob MH, Priori SG, Sanatani S, Wilde AAM, Deo RC, Roberts JD. An International Multicenter Evaluation of Inheritance Patterns, Arrhythmic Risks, and Underlying Mechanisms of CASQ2-Catecholaminergic Polymorphic Ventricular Tachycardia. Circulation 2020; 142:932-947. [PMID: 32693635 PMCID: PMC7484339 DOI: 10.1161/circulationaha.120.045723] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
BACKGROUND Genetic variants in calsequestrin-2 (CASQ2) cause an autosomal recessive form of catecholaminergic polymorphic ventricular tachycardia (CPVT), although isolated reports have identified arrhythmic phenotypes among heterozygotes. Improved insight into the inheritance patterns, arrhythmic risks, and molecular mechanisms of CASQ2-CPVT was sought through an international multicenter collaboration. METHODS Genotype-phenotype segregation in CASQ2-CPVT families was assessed, and the impact of genotype on arrhythmic risk was evaluated using Cox regression models. Putative dominant CASQ2 missense variants and the established recessive CASQ2-p.R33Q variant were evaluated using oligomerization assays and their locations mapped to a recent CASQ2 filament structure. RESULTS A total of 112 individuals, including 36 CPVT probands (24 homozygotes/compound heterozygotes and 12 heterozygotes) and 76 family members possessing at least 1 presumed pathogenic CASQ2 variant, were identified. Among CASQ2 homozygotes and compound heterozygotes, clinical penetrance was 97.1% and 26 of 34 (76.5%) individuals had experienced a potentially fatal arrhythmic event with a median age of onset of 7 years (95% CI, 6-11). Fifty-one of 66 CASQ2 heterozygous family members had undergone clinical evaluation, and 17 of 51 (33.3%) met diagnostic criteria for CPVT. Relative to CASQ2 heterozygotes, CASQ2 homozygote/compound heterozygote genotype status in probands was associated with a 3.2-fold (95% CI, 1.3-8.0; P=0.013) increased hazard of a composite of cardiac syncope, aborted cardiac arrest, and sudden cardiac death, but a 38.8-fold (95% CI, 5.6-269.1; P<0.001) increased hazard in genotype-positive family members. In vitro turbidity assays revealed that p.R33Q and all 6 candidate dominant CASQ2 missense variants evaluated exhibited filamentation defects, but only p.R33Q convincingly failed to dimerize. Structural analysis revealed that 3 of these 6 putative dominant negative missense variants localized to an electronegative pocket considered critical for back-to-back binding of dimers. CONCLUSIONS This international multicenter study of CASQ2-CPVT redefines its heritability and confirms that pathogenic heterozygous CASQ2 variants may manifest with a CPVT phenotype, indicating a need to clinically screen these individuals. A dominant mode of inheritance appears intrinsic to certain missense variants because of their location and function within the CASQ2 filament structure.
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Affiliation(s)
- Kevin Ng
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
- Cairns Hospital, Queensland, Australia
| | - Erron W. Titus
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California, USA
| | - Krystien V. Lieve
- Amsterdam University Medical Centre, University of Amsterdam, Heart Centre, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
| | - Thomas M. Roston
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrea Mazzanti
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
- Molecular Cardiology, Istituti Clinici Scientifici Maugeri, Istituto di Ricovero e Cura a Carattere Scientifico and Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Frederick H. Deiter
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California, USA
| | - Isabelle Denjoy
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
- Service de Cardiologie et CNMR Maladies Cardiacques Héréditaires Rares, Hôpital Bichat, Paris, France
| | - Jodie Ingles
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute, The University of Sydney, Sydney, Australia
| | - Jan Till
- Department of Cardiology, Royal Brompton Hospital, London, United Kingdom
| | - Tomas Robyns
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
- Department of Cardiovascular Disease, University Hospitals Leuven, Leuven, Belgium
| | - Sean P. Connors
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Memorial University, St. John’s, Newfoundland and Labrador, Canada
| | | | - Dominic J. Abrams
- Inherited Cardiac Arrhythmia Program, Boston Children’s Hospital, Harvard Medical School, Massachusetts, USA
| | - Benjamin Pang
- Arrhythmia Service, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Melvin M. Scheinman
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, California, USA
| | - J. Martijn Bos
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, Minnesota, USA
| | - Stephen A. Duffett
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Memorial University, St. John’s, Newfoundland and Labrador, Canada
| | - Christian van der Werf
- Amsterdam University Medical Centre, University of Amsterdam, Heart Centre, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
| | - Alice Maltret
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
- Service de Cardiologie et CNMR Maladies Cardiacques Héréditaires Rares, Hôpital Bichat, Paris, France
| | - Martin S. Green
- Arrhythmia Service, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Julie Rutberg
- Arrhythmia Service, University of Ottawa Heart Institute, Ottawa, Ontario, Canada
| | - Seshadri Balaji
- Department of Pediatrics, Division of Cardiology, Oregon Health & Science University, Portland, Oregon, USA
| | - Julia Cadrin-Tourigny
- Cardiovascular Genetics Center, Montreal Heart Institute, Université de Montréal, Montréal, Canada
| | - Kate M. Orland
- University of Wisconsin-Madison Inherited Arrhythmia Clinic, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Linda M. Knight
- Children’s Healthcare of Atlanta, Sibley Heart Center Cardiology, Atlanta, Georgia, USA
| | - Caitlin Brateng
- Children’s Hospital Colorado, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Jeremy Wu
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
| | - Anthony S. Tang
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
| | - Allan C. Skanes
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
| | - Jaimie Manlucu
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
| | - Jeff S. Healey
- Population Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Craig T. January
- University of Wisconsin-Madison Inherited Arrhythmia Clinic, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Cellular and Molecular Arrhythmia Research Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Andrew D. Krahn
- Heart Rhythm Services, Division of Cardiology, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kathryn K. Collins
- Children’s Hospital Colorado, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Kathleen R. Maginot
- Department of Pediatrics, University of Wisconsin School of Medicine & Public Health, Madison, Wisconsin, USA
| | - Peter Fischbach
- Children’s Healthcare of Atlanta, Sibley Heart Center Cardiology, Atlanta, Georgia, USA
| | - Susan P. Etheridge
- Department of Pediatrics, University of Utah, and Primary Children’s Hospital, Salt Lake City, Utah, USA
| | - Lee L. Eckhardt
- University of Wisconsin-Madison Inherited Arrhythmia Clinic, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Cellular and Molecular Arrhythmia Research Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Robert M. Hamilton
- The Labatt Family Heart Centre (Department of Pediatrics) and Translational Medicine, The Hospital for Sick Children and the University of Toronto, Toronto, Ontario, Canada
| | - Michael J. Ackerman
- Departments of Cardiovascular Medicine (Division of Heart Rhythm Services), Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), and Molecular Pharmacology & Experimental Therapeutics (Windland Smith Rice Sudden Death Genomics Laboratory), Mayo Clinic, Rochester, Minnesota, USA
| | | | - Christopher Semsarian
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute, The University of Sydney, Sydney, Australia
| | - Natalia Jura
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California, USA
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, California, USA
| | - Antoine Leenhardt
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
- Service de Cardiologie et CNMR Maladies Cardiacques Héréditaires Rares, Hôpital Bichat, Paris, France
| | - Michael H. Gollob
- Department of Physiology and Department of Medicine, Toronto General Hospital, University of Toronto, Ontario, Canada
| | - Silvia G. Priori
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
- Molecular Cardiology, Istituti Clinici Scientifici Maugeri, Istituto di Ricovero e Cura a Carattere Scientifico and Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Shubhayan Sanatani
- Department of Pediatrics, Children’s Heart Centre, BC Children’s Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Arthur A. M. Wilde
- Amsterdam University Medical Centre, University of Amsterdam, Heart Centre, Department of Clinical and Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, the Netherlands
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart
| | - Rahul C. Deo
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California, USA
- Department of Medicine, University of California San Francisco, San Francisco, California, USA
- One Brave Idea and Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Harvard University, Boston, Massachusetts, USA
| | - Jason D. Roberts
- Section of Cardiac Electrophysiology, Division of Cardiology, Department of Medicine, Western University, London, Ontario, Canada
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12
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Lemme M, Braren I, Prondzynski M, Aksehirlioglu B, Ulmer BM, Schulze ML, Ismaili D, Meyer C, Hansen A, Christ T, Lemoine MD, Eschenhagen T. Chronic intermittent tachypacing by an optogenetic approach induces arrhythmia vulnerability in human engineered heart tissue. Cardiovasc Res 2020; 116:1487-1499. [PMID: 31598634 PMCID: PMC7314638 DOI: 10.1093/cvr/cvz245] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 07/31/2019] [Accepted: 10/04/2019] [Indexed: 01/01/2023] Open
Abstract
AIMS Chronic tachypacing is commonly used in animals to induce cardiac dysfunction and to study mechanisms of heart failure and arrhythmogenesis. Human induced pluripotent stem cells (hiPSC) may replace animal models to overcome species differences and ethical problems. Here, 3D engineered heart tissue (EHT) was used to investigate the effect of chronic tachypacing on hiPSC-cardiomyocytes (hiPSC-CMs). METHODS AND RESULTS To avoid cell toxicity by electrical pacing, we developed an optogenetic approach. EHTs were transduced with lentivirus expressing channelrhodopsin-2 (H134R) and stimulated by 15 s bursts of blue light pulses (0.3 mW/mm2, 30 ms, 3 Hz) separated by 15 s without pacing for 3 weeks. Chronic optical tachypacing did not affect contractile peak force, but induced faster contraction kinetics, shorter action potentials, and shorter effective refractory periods. This electrical remodelling increased vulnerability to tachycardia episodes upon electrical burst pacing. Lower calsequestrin 2 protein levels, faster diastolic depolarization (DD) and efficacy of JTV-519 (46% at 1 µmol/L) to terminate tachycardia indicate alterations of Ca2+ handling being part of the underlying mechanism. However, other antiarrhythmic compounds like flecainide (69% at 1 µmol/L) and E-4031 (100% at 1 µmol/L) were also effective, but not ivabradine (1 µmol/L) or SEA0400 (10 µmol/L). CONCLUSION We demonstrated a high vulnerability to tachycardia of optically tachypaced hiPSC-CMs in EHT and the effective termination by ryanodine receptor stabilization, sodium or hERG potassium channel inhibition. This new model might serve as a preclinical tool to test antiarrhythmic drugs increasing the insight in treating ventricular tachycardia.
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Affiliation(s)
- Marta Lemme
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Ingke Braren
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Maksymilian Prondzynski
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
- Department of Cardiology, Boston Children’s Hospital, Harvard Medical School, Boston, USA
| | - Bülent Aksehirlioglu
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| | - Bärbel M Ulmer
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Mirja L Schulze
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Djemail Ismaili
- Department of Cardiology-Electrophysiology, University Heart Center, 20246 Hamburg, Germany
| | - Christian Meyer
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
- Department of Cardiology-Electrophysiology, University Heart Center, 20246 Hamburg, Germany
| | - Arne Hansen
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Torsten Christ
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
| | - Marc D Lemoine
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
- Department of Cardiology-Electrophysiology, University Heart Center, 20246 Hamburg, Germany
| | - Thomas Eschenhagen
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, 20246 Hamburg, Germany
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13
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Wang Q, Michalak M. Calsequestrin. Structure, function, and evolution. Cell Calcium 2020; 90:102242. [PMID: 32574906 DOI: 10.1016/j.ceca.2020.102242] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 06/05/2020] [Accepted: 06/06/2020] [Indexed: 12/25/2022]
Abstract
Calsequestrin is the major Ca2+ binding protein in the sarcoplasmic reticulum (SR), serves as the main Ca2+ storage and buffering protein and is an important regulator of Ca2+ release channels in both skeletal and cardiac muscle. It is anchored at the junctional SR membrane through interactions with membrane proteins and undergoes reversible polymerization with increasing Ca2+ concentration. Calsequestrin provides high local Ca2+ at the junctional SR and communicates changes in luminal Ca2+ concentration to Ca2+ release channels, thus it is an essential component of excitation-contraction coupling. Recent studies reveal new insights on calsequestrin trafficking, Ca2+ binding, protein evolution, protein-protein interactions, stress responses and the molecular basis of related human muscle disease, including catecholaminergic polymorphic ventricular tachycardia (CPVT). Here we provide a comprehensive overview of calsequestrin, with recent advances in structure, diverse functions, phylogenetic analysis, and its role in muscle physiology, stress responses and human pathology.
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Affiliation(s)
- Qian Wang
- Department of Biochemistry, University of Alberta, Edmonton, AB, T6H 2S7, Canada
| | - Marek Michalak
- Department of Biochemistry, University of Alberta, Edmonton, AB, T6H 2S7, Canada.
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14
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Liu T, Xiong F, Qi XY, Xiao J, Villeneuve L, Abu-Taha I, Dobrev D, Huang C, Nattel S. Altered calcium handling produces reentry-promoting action potential alternans in atrial fibrillation-remodeled hearts. JCI Insight 2020; 5:133754. [PMID: 32255765 DOI: 10.1172/jci.insight.133754] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 03/25/2020] [Indexed: 12/19/2022] Open
Abstract
Atrial fibrillation (AF) alters atrial cardiomyocyte (ACM) Ca2+ handling, promoting ectopic beat formation. We examined the effects of AF-associated remodeling on Ca2+-related action potential dynamics and consequences for AF susceptibility. AF was maintained electrically in dogs by right atrial (RA) tachypacing. ACMs isolated from AF dogs showed increased Ca2+ release refractoriness, spontaneous Ca2+ spark frequency, and cycle length (CL) threshold for Ca2+ and action potential duration (APD) alternans versus controls. AF increased the in situ CL threshold for Ca2+/APD alternans and spatial dispersion in Ca2+ release recovery kinetics, leading to spatially discordant alternans associated with reentrant rotor formation and susceptibility to AF induction/maintenance. The clinically available agent dantrolene reduced Ca2+ leak and CL threshold for Ca2+/APD alternans in ACMs and AF dog right atrium, while suppressing AF susceptibility; caffeine increased Ca2+ leak and CL threshold for Ca2+/APD alternans in control dog ACMs and RA tissues. In vivo, the atrial repolarization alternans CL threshold was increased in AF versus control, as was AF vulnerability. Intravenous dantrolene restored repolarization alternans threshold and reduced AF vulnerability. Immunoblots showed reduced expression of total and phosphorylated ryanodine receptors and calsequestrin in AF and unchanged phospholamban/SERCA expression. Thus, along with promoting spontaneous ectopy, AF-induced Ca2+ handling abnormalities favor AF by enhancing vulnerability to repolarization alternans, promoting initiation and maintenance of reentrant activity; dantrolene provides a lead molecule to target this mechanism.
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Affiliation(s)
- Tao Liu
- Montreal Heart Institute, Department of Medicine, Université de Montréal, Montréal, Québec, Canada.,Department of Cardiology, Renmin Hospital of Wuhan University, China.,Cardiovascular Research Institute, Wuhan University, China.,Hubei Key Laboratory of Cardiology, Wuhan, China
| | - Feng Xiong
- Montreal Heart Institute, Department of Medicine, Université de Montréal, Montréal, Québec, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
| | - Xiao-Yan Qi
- Montreal Heart Institute, Department of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Jiening Xiao
- Montreal Heart Institute, Department of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Louis Villeneuve
- Montreal Heart Institute, Department of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Issam Abu-Taha
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Germany
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Germany
| | - Congxin Huang
- Department of Cardiology, Renmin Hospital of Wuhan University, China.,Cardiovascular Research Institute, Wuhan University, China.,Hubei Key Laboratory of Cardiology, Wuhan, China
| | - Stanley Nattel
- Montreal Heart Institute, Department of Medicine, Université de Montréal, Montréal, Québec, Canada.,Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada.,Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Germany.,IHU LIRYC Institute, Fondation Bordeaux Université, Bordeaux, France
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15
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Li Q, Guo R, Gao L, Cui L, Zhao Z, Yu X, Yuan Y, Xu X. CASQ2 variants in Chinese children with catecholaminergic polymorphic ventricular tachycardia. Mol Genet Genomic Med 2019; 7:e949. [PMID: 31482657 PMCID: PMC6825949 DOI: 10.1002/mgg3.949] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 07/15/2019] [Accepted: 08/12/2019] [Indexed: 01/04/2023] Open
Abstract
Background Biallelic variants of the CASQ2 are known to cause the autosomal recessive form of catecholaminergic polymorphic ventricular tachycardia (CPVT), an inherited disease that predisposes young individuals to syncope and sudden cardiac death. To date, only about 24 CASQ2 variants have been reported in association with CPVT pathogenesis; furthermore, studies in Asians, especially in the Chinese population, are relatively rare. The aim of this study was to detect CASQ2 variants in Chinese patients with CPVT. Methods We used targeted next‐generation sequencing (NGS) to identify CASQ2 variants in Chinese patients with CPVT. A screening process was performed to prioritize rare variants of potential functional significance. Sanger sequencing was conducted to conform the candidate variants and determine the parental origin. Results We identified seven different CASQ2 variants, of which three (c.1074_1075delinsC, c.1175_1178delACAG, and c.838+1G>A) have not been previously reported. The variants exhibited autosomal recessive inheritance, and were detected in four unrelated Chinese families with CPVT. They included a nonsense variant c.97C>T (p.R33*) and a missense variant c.748C>T (p.R250C) in Family 1 with three CPVT patients; two heterozygous frameshift variants, c.1074_1075delinsC (p.G359Afs*12) and c.1175_1178delACAG (p.D392Vfs*84), in Family 2 with one CPVT patient; one pathogenic homozygous variant c.98G>A (p.R33Q) of CASQ2 in the CPVT patient of Family 3; and two heterozygous splicing variants, (c.532+1G>A) and (c.838+1G>A), in Family 4 with one CPVT patient. Conclusion To our knowledge, this is the first systematic study of Chinese children with CASQ2 variants. Our work further expands the genetic spectrum of CASQ2‐associated CPVT.
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Affiliation(s)
- Qirui Li
- Department of Cardiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Ruolan Guo
- Beijing Key Laboratory for Genetics of Birth Defects, Beijing Pediatric Research Institute, Beijing, China.,Genetics and Birth Defects Control Center, National Center for Children's Health, Beijing, China.,MOE Key Laboratory of Major Diseases in Children, Beijing, China.,Beijing Children's Hospital, Capital Medical University, Beijing, China
| | - Lu Gao
- Department of Cardiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Lang Cui
- Department of Cardiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Zhihui Zhao
- Department of Cardiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Xia Yu
- Department of Cardiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Yue Yuan
- Department of Cardiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
| | - Xiwei Xu
- Internal Medicine Teaching and Research Department, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China
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16
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Calcium as a Key Player in Arrhythmogenic Cardiomyopathy: Adhesion Disorder or Intracellular Alteration? Int J Mol Sci 2019; 20:ijms20163986. [PMID: 31426283 PMCID: PMC6721231 DOI: 10.3390/ijms20163986] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 08/08/2019] [Accepted: 08/14/2019] [Indexed: 12/20/2022] Open
Abstract
Arrhythmogenic cardiomyopathy (ACM) is an inherited heart disease characterized by sudden death in young people and featured by fibro-adipose myocardium replacement, malignant arrhythmias, and heart failure. To date, no etiological therapies are available. Mutations in desmosomal genes cause abnormal mechanical coupling, trigger pro-apoptotic signaling pathways, and induce fibro-adipose replacement. Here, we discuss the hypothesis that the ACM causative mechanism involves a defect in the expression and/or activity of the cardiac Ca2+ handling machinery, focusing on the available data supporting this hypothesis. The Ca2+ toolkit is heavily remodeled in cardiomyocytes derived from a mouse model of ACM defective of the desmosomal protein plakophilin-2. Furthermore, ACM-related mutations were found in genes encoding for proteins involved in excitation‒contraction coupling, e.g., type 2 ryanodine receptor and phospholamban. As a consequence, the sarcoplasmic reticulum becomes more eager to release Ca2+, thereby inducing delayed afterdepolarizations and impairing cardiac contractility. These data are supported by preliminary observations from patient induced pluripotent stem-cell-derived cardiomyocytes. Assessing the involvement of Ca2+ signaling in the pathogenesis of ACM could be beneficial in the treatment of this life-threatening disease.
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17
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Hwang HS, Baldo MP, Rodriguez JP, Faggioni M, Knollmann BC. Efficacy of Flecainide in Catecholaminergic Polymorphic Ventricular Tachycardia Is Mutation-Independent but Reduced by Calcium Overload. Front Physiol 2019; 10:992. [PMID: 31456692 PMCID: PMC6701460 DOI: 10.3389/fphys.2019.00992] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 07/18/2019] [Indexed: 11/22/2022] Open
Abstract
Background The dual Na+ and cardiac Ca2+-release channel inhibitor, Flecainide (FLEC) is effective in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT), a disease caused by mutations in cardiac Ca2+-release channels (RyR2), calsequestrin (Casq2), or calmodulin. FLEC suppresses spontaneous Ca2+ waves in Casq2-knockout (Casq2−/−) cardiomyocytes, a CPVT model. However, a report failed to find FLEC efficacy against Ca2+ waves in another CPVT model, RyR2-R4496C heterozygous mice (RyR2R4496C+/−), raising the possibility that FLEC efficacy may be mutation dependent. Objective To address this controversy, we compared FLEC in Casq2−/− and RyR2R4496C+/− cardiomyocytes and mice under identical conditions. Methods After 30 min exposure to FLEC (6 μM) or vehicle (VEH), spontaneous Ca2+ waves were quantified during a 40 s pause after 1 Hz pacing train in the presence of isoproterenol (ISO, 1 μM). FLEC efficacy was also tested in vivo using a low dose (LOW: 3 mg/kg ISO + 60 mg/kg caffeine) or a high dose catecholamine challenge (HIGH: 3 mg/kg ISO + 120 mg/kg caffeine). Results In cardiomyocytes, FLEC efficacy was dependent on extracellular [Ca2+]. At 2 mM [Ca2+], only Casq2−/− myocytes exhibited Ca2+ waves, which were strongly suppressed by FLEC. At 3 mM [Ca2+] both groups exhibited Ca2+ waves that were suppressed by FLEC. At 4 mM [Ca2+], FLEC no longer suppressed Ca2+ waves in both groups. Analogous to the results in myocytes, RyR2R4496C+/− mice (n = 12) had significantly lower arrhythmia scores than Casq2−/− mice (n = 9), but the pattern of FLEC efficacy was similar in both groups (i.e., reduced FLEC efficacy after HIGH dose catecholamine challenge). Conclusion FLEC inhibits Ca2+ waves in RyR2R4496C+/− cardiomyocytes, indicating that RyR2 channel block by FLEC is not mutation-specific. However, FLEC efficacy is reduced by Ca2+ overload in vitro or by high dose catecholamine challenge in vivo, which could explain conflicting literature reports.
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Affiliation(s)
- Hyun Seok Hwang
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, United States.,Division of Clinical Pharmacology, Oates Institute for Experimental Therapeutics, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Marcelo P Baldo
- Division of Clinical Pharmacology, Oates Institute for Experimental Therapeutics, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Jose Pindado Rodriguez
- Department of Nutrition, Food and Exercise Sciences, Florida State University, Tallahassee, FL, United States
| | - Michela Faggioni
- Division of Clinical Pharmacology, Oates Institute for Experimental Therapeutics, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Bjorn C Knollmann
- Division of Clinical Pharmacology, Oates Institute for Experimental Therapeutics, Vanderbilt University School of Medicine, Nashville, TN, United States
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18
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Pollak AJ, Liu C, Gudlur A, Mayfield JE, Dalton ND, Gu Y, Chen J, Heller Brown J, Hogan PG, Wiley SE, Peterson KL, Dixon JE. A secretory pathway kinase regulates sarcoplasmic reticulum Ca 2+ homeostasis and protects against heart failure. eLife 2018; 7:41378. [PMID: 30520731 PMCID: PMC6298778 DOI: 10.7554/elife.41378] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 12/03/2018] [Indexed: 12/17/2022] Open
Abstract
Ca2+ signaling is important for many cellular and physiological processes, including cardiac function. Although sarcoplasmic reticulum (SR) proteins involved in Ca2+ signaling have been shown to be phosphorylated, the biochemical and physiological roles of protein phosphorylation within the lumen of the SR remain essentially uncharacterized. Our laboratory recently identified an atypical protein kinase, Fam20C, which is uniquely localized to the secretory pathway lumen. Here, we show that Fam20C phosphorylates several SR proteins involved in Ca2+ signaling, including calsequestrin2 and Stim1, whose biochemical activities are dramatically regulated by Fam20C mediated phosphorylation. Notably, phosphorylation of Stim1 by Fam20C enhances Stim1 activation and store-operated Ca2+ entry. Physiologically, mice with Fam20c ablated in cardiomyocytes develop heart failure following either aging or induced pressure overload. We extended these observations to show that non-muscle cells lacking Fam20C display altered ER Ca2+ signaling. Overall, we show that Fam20C plays an overarching role in ER/SR Ca2+ homeostasis and cardiac pathophysiology.
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Affiliation(s)
- Adam J Pollak
- Department of Pharmacology, University of California, San Diego, San Diego, United States
| | - Canzhao Liu
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Aparna Gudlur
- Division of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology, San Diego, United States
| | - Joshua E Mayfield
- Department of Pharmacology, University of California, San Diego, San Diego, United States
| | - Nancy D Dalton
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Yusu Gu
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Ju Chen
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Joan Heller Brown
- Department of Pharmacology, University of California, San Diego, San Diego, United States
| | - Patrick G Hogan
- Division of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology, San Diego, United States.,Program in Immunology, University of California, San Diego, San Diego, United States.,Moores Cancer Center, University of California, San Diego, San Diego, United States
| | - Sandra E Wiley
- Department of Pharmacology, University of California, San Diego, San Diego, United States
| | - Kirk L Peterson
- Department of Medicine, University of California, San Diego, San Diego, United States
| | - Jack E Dixon
- Department of Pharmacology, University of California, San Diego, San Diego, United States.,Department of Cellular and Molecular Medicine, University of California, San Diego, San Diego, United States.,Department of Chemistry and Biochemistry, University of California, San Diego, San Diego, United States
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19
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Smith JGW, Owen T, Bhagwan JR, Mosqueira D, Scott E, Mannhardt I, Patel A, Barriales-Villa R, Monserrat L, Hansen A, Eschenhagen T, Harding SE, Marston S, Denning C. Isogenic Pairs of hiPSC-CMs with Hypertrophic Cardiomyopathy/LVNC-Associated ACTC1 E99K Mutation Unveil Differential Functional Deficits. Stem Cell Reports 2018; 11:1226-1243. [PMID: 30392975 PMCID: PMC6235010 DOI: 10.1016/j.stemcr.2018.10.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 10/04/2018] [Accepted: 10/05/2018] [Indexed: 12/14/2022] Open
Abstract
Hypertrophic cardiomyopathy (HCM) is a primary disorder of contractility in heart muscle. To gain mechanistic insight and guide pharmacological rescue, this study models HCM using isogenic pairs of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) carrying the E99K-ACTC1 cardiac actin mutation. In both 3D engineered heart tissues and 2D monolayers, arrhythmogenesis was evident in all E99K-ACTC1 hiPSC-CMs. Aberrant phenotypes were most common in hiPSC-CMs produced from the heterozygote father. Unexpectedly, pathological phenotypes were less evident in E99K-expressing hiPSC-CMs from the two sons. Mechanistic insight from Ca2+ handling expression studies prompted pharmacological rescue experiments, wherein dual dantroline/ranolazine treatment was most effective. Our data are consistent with E99K mutant protein being a central cause of HCM but the three-way interaction between the primary genetic lesion, background (epi)genetics, and donor patient age may influence the pathogenic phenotype. This illustrates the value of isogenic hiPSC-CMs in genotype-phenotype correlations.
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Affiliation(s)
- James G W Smith
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK; Faculty of Medicine and Health Sciences, Norwich Medical School, University of East Anglia, Norwich Research Park, Norwich NR4 7UQ, UK.
| | - Thomas Owen
- National Heart and Lung Institute, Imperial College, London W12 0NN, UK
| | - Jamie R Bhagwan
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Diogo Mosqueira
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Elizabeth Scott
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK
| | - Ingra Mannhardt
- Institute of Experimental Pharmacology and Toxicology, University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Asha Patel
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK; Department of Gene Therapy, National Heart and Lung Institute, Imperial College London SW3 6LR, UK
| | - Roberto Barriales-Villa
- Inherited Cardiovascular Diseases Unit, Cardiology Service, Complexo Hospitalario Universitario A Coruña, Servizo Galego de Saúde (SERGAS), Universidade da Coruña, A Coruña, Spain; Instituto de Investigación Biomédica de A Coruña (INIBIC), A Coruña, Spain
| | - Lorenzo Monserrat
- Instituto de Investigación Biomédica de A Coruña (INIBIC), A Coruña, Spain; Health in Code S.L., Cardiology Department, A Coruña, Spain
| | - Arne Hansen
- Institute of Experimental Pharmacology and Toxicology, University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Thomas Eschenhagen
- Institute of Experimental Pharmacology and Toxicology, University Medical Centre, Hamburg-Eppendorf, Hamburg, Germany; DZHK (German Centre for Cardiovascular Research), Partner Site Hamburg/Kiel/Lübeck, Hamburg, Germany
| | - Sian E Harding
- National Heart and Lung Institute, Imperial College, London W12 0NN, UK
| | - Steve Marston
- National Heart and Lung Institute, Imperial College, London W12 0NN, UK
| | - Chris Denning
- Wolfson Centre for Stem Cells, Tissue Engineering and Modelling, Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, UK.
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20
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Rebrova TY, Muslimova EF, Kondratieva DS, Budnikova OV, Ahmedov SD, Afanasiev SA, Popov SV. The Role of Ca2+-ATPase 2a (ATP2A2), Ryanodine Receptors (RYR2), and Calsequestrin (CASQ2) Gene Polymorphisms in the Development of Heart Failure. RUSS J GENET+ 2018. [DOI: 10.1134/s102279541806008x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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21
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Fischer E, Gottschalk A, Schüler C. An optogenetic arrhythmia model to study catecholaminergic polymorphic ventricular tachycardia mutations. Sci Rep 2017; 7:17514. [PMID: 29235522 PMCID: PMC5727474 DOI: 10.1038/s41598-017-17819-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/01/2017] [Indexed: 11/08/2022] Open
Abstract
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a condition of abnormal heart rhythm (arrhythmia), induced by physical activity or stress. Mutations in ryanodine receptor 2 (RyR2), a Ca2+ release channel located in the sarcoplasmic reticulum (SR), or calsequestrin 2 (CASQ2), a SR Ca2+ binding protein, are linked to CPVT. For specific drug development and to study distinct arrhythmias, simple models are required to implement and analyze such mutations. Here, we introduced CPVT inducing mutations into the pharynx of Caenorhabditis elegans, which we previously established as an optogenetically paced heart model. By electrophysiology and video-microscopy, we characterized mutations in csq-1 (CASQ2 homologue) and unc-68 (RyR2 homologue). csq-1 deletion impaired pharynx function and caused missed pumps during 3.7 Hz pacing. Deletion mutants of unc-68, and in particular the point mutant UNC-68(R4743C), analogous to the established human CPVT mutant RyR2(R4497C), were unable to follow 3.7 Hz pacing, with progressive defects during long stimulus trains. The pharynx either locked in pumping at half the pacing frequency or stopped pumping altogether, possibly due to UNC-68 leakiness and/or malfunctional SR Ca2+ homeostasis. Last, we could reverse this 'worm arrhythmia' by the benzothiazepine S107, establishing the nematode pharynx for studying specific CPVT mutations and for drug screening.
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Affiliation(s)
- Elisabeth Fischer
- Buchmann Institute for Molecular Life Sciences, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany
- Institute of Biophysical Chemistry, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany
- University of Edinburgh, Centre for Integrative Physiology, Hugh Robson Building, George Square, Edinburgh, EH8 9XE, UK
| | - Alexander Gottschalk
- Buchmann Institute for Molecular Life Sciences, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany.
- Institute of Biophysical Chemistry, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany.
- Cluster of Excellence Frankfurt - Macromolecular Complexes, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany.
| | - Christina Schüler
- Buchmann Institute for Molecular Life Sciences, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany.
- Institute of Biophysical Chemistry, Goethe University, Max von Laue Strasse 15, D-60438, Frankfurt, Germany.
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22
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Walweel K, Oo YW, Laver DR. The emerging role of calmodulin regulation of RyR2 in controlling heart rhythm, the progression of heart failure and the antiarrhythmic action of dantrolene. Clin Exp Pharmacol Physiol 2017; 44:135-142. [PMID: 27626620 DOI: 10.1111/1440-1681.12669] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/27/2016] [Accepted: 09/09/2016] [Indexed: 11/28/2022]
Abstract
Cardiac output and rhythm depend on the release and the take-up of calcium from the sarcoplasmic reticulum (SR). Excessive diastolic calcium leak from the SR due to dysfunctional calcium release channels (RyR2) contributes to the formation of delayed after-depolarizations, which underlie the fatal arrhythmias that occur in heart failure and inherited syndromes. Calmodulin (CaM) is a calcium-binding protein that regulates target proteins and acts as a calcium sensor. CaM is comprised of two calcium-binding EF-hand domains and a flexible linker. CaM is an accessory protein that partially inhibits RyR2 channel activity. CaM is critical for normal cardiac function, and altered CaM binding and efficacy may contribute to defects in SR calcium release. The present paper reviews CaM binding to RyR2 and how it regulates RyR2 channel activity. It then goes on to review how mutations in the CaM amino acid sequence give rise to inherited syndromes such as Catecholaminergic Polymorphic Ventricular Tachychardia (CPVT) and long QT syndrome (LQTS). In addition, the role of reduced CaM binding to RyR2 that results from RyR2 phosphorylation or from oxidation of either RyR2 or CaM contributes to the progression of heart failure is reviewed. Finally, this manuscript reviews recent evidence that CaM binding to RyR2 is required for the inhibitory action of a pharmaceutical agent (dantrolene) on RyR2. Dantrolene is a clinically used muscle relaxant that has recently been found to exert antiarrhythmic effects against SR Ca2+ overload arrhythmias.
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Affiliation(s)
- Kafa Walweel
- School of Biomedical Sciences and Pharmacy, University of Newcastle and Hunter Medical Research Institute, Callaghan, NSW, 2308, Australia
| | - Ye Win Oo
- School of Biomedical Sciences and Pharmacy, University of Newcastle and Hunter Medical Research Institute, Callaghan, NSW, 2308, Australia
| | - Derek R Laver
- School of Biomedical Sciences and Pharmacy, University of Newcastle and Hunter Medical Research Institute, Callaghan, NSW, 2308, Australia
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23
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Dulhunty AF, Wei-LaPierre L, Casarotto MG, Beard NA. Core skeletal muscle ryanodine receptor calcium release complex. Clin Exp Pharmacol Physiol 2017; 44:3-12. [PMID: 27696487 DOI: 10.1111/1440-1681.12676] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2016] [Revised: 09/27/2016] [Accepted: 09/27/2016] [Indexed: 12/15/2022]
Abstract
The core skeletal muscle ryanodine receptor (RyR1) calcium release complex extends through three compartments of the muscle fibre, linking the extracellular environment through the cytoplasmic junctional gap to the lumen of the internal sarcoplasmic reticulum (SR) calcium store. The protein complex is essential for skeletal excitation-contraction (EC)-coupling and skeletal muscle function. Its importance is highlighted by perinatal death if any one of the EC-coupling components are missing and by myopathies associated with mutation of any of the proteins. The proteins essential for EC-coupling include the DHPR α1S subunit in the transverse tubule membrane, the DHPR β1a subunit in the cytosol and the RyR1 ion channel in the SR membrane. The other core proteins are triadin and junctin and calsequestrin, associated mainly with SR. These SR proteins are not essential for survival but exert structural and functional influences that modify the gain of EC-coupling and maintain normal muscle function. This review summarises our current knowledge of the individual protein/protein interactions within the core complex and their overall contribution to EC-coupling. We highlight significant areas that provide a continuing challenge for the field. Additional important components of the Ca2+ release complex, such as FKBP12, calmodulin, S100A1 and Stac3 are identified and reviewed elsewhere.
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Affiliation(s)
- Angela F Dulhunty
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Lan Wei-LaPierre
- Department of Physiology and Pharmacology, University of Rochester Medical Center, Rochester, NY, USA
| | - Marco G Casarotto
- John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Nicole A Beard
- Health Research Institute, University of Canberra, Canberra, ACT, Australia
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24
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Ríos E. Perspectives on "Control of Ca release from within the cardiac sarcoplasmic reticulum". J Gen Physiol 2017; 149:833-836. [PMID: 28798278 PMCID: PMC5583715 DOI: 10.1085/jgp.201711847] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 07/24/2017] [Indexed: 12/11/2022] Open
Abstract
Five groups of experts unravel the complex modulation of a function crucial for the beating heart.
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Affiliation(s)
- Eduardo Ríos
- Section of Cellular Signaling, Department of Physiology and Biophysics, Rush University, Chicago, IL
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25
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Györke S, Belevych AE, Liu B, Kubasov IV, Carnes CA, Radwański PB. The role of luminal Ca regulation in Ca signaling refractoriness and cardiac arrhythmogenesis. J Gen Physiol 2017; 149:877-888. [PMID: 28798279 PMCID: PMC5583712 DOI: 10.1085/jgp.201711808] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2017] [Revised: 06/19/2017] [Accepted: 07/12/2017] [Indexed: 01/05/2023] Open
Abstract
Györke et al. discuss the role of sarcoplasmic reticulum Ca2+ in cardiac refractoriness and pathological implications.
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Affiliation(s)
- Sándor Györke
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH .,Davis Heart and Lung Research Institute, Columbus, OH
| | - Andriy E Belevych
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH.,Davis Heart and Lung Research Institute, Columbus, OH
| | - Bin Liu
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH.,Davis Heart and Lung Research Institute, Columbus, OH
| | - Igor V Kubasov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, St. Petersburg, Russia
| | - Cynthia A Carnes
- College of Pharmacy, The Ohio State University, Columbus, OH.,Davis Heart and Lung Research Institute, Columbus, OH
| | - Przemysław B Radwański
- College of Pharmacy, The Ohio State University, Columbus, OH.,Davis Heart and Lung Research Institute, Columbus, OH
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26
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Incardona JP. Molecular Mechanisms of Crude Oil Developmental Toxicity in Fish. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2017; 73:19-32. [PMID: 28695261 DOI: 10.1007/s00244-017-0381-1] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 02/15/2017] [Indexed: 05/25/2023]
Abstract
With major oil spills in Korea, the United States, and China in the past decade, there has been a dramatic increase in the number of studies characterizing the developmental toxicity of crude oil and its associated polycyclic aromatic compounds (PACs). The use of model fish species with associated tools for genetic manipulation, combined with high throughput genomics techniques in nonmodel fish species, has led to significant advances in understanding the cellular and molecular bases of functional and morphological defects arising from embryonic exposure to crude oil. Following from the identification of the developing heart as the primary target of crude oil developmental toxicity, studies on individual PACs have revealed a diversity of cardiotoxic mechanisms. For some PACs that are strong agonists of the aryl hydrocarbon receptor (AHR), defects in heart development arise in an AHR-dependent manner, which has been shown for potent organochlorine agonists, such as dioxins. However, crude oil contains a much larger fraction of compounds that have been found to interfere directly with cardiomyocyte physiology in an AHR-independent manner. By comparing the cellular and molecular responses to AHR-independent and AHR-dependent toxicity, this review focuses on new insights into heart-specific pathways underlying both acute and secondary adverse outcomes to crude oil exposure during fish development.
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Affiliation(s)
- John P Incardona
- Environmental and Fisheries Sciences Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA Fisheries, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA.
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27
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Calsequestrin depolymerizes when calcium is depleted in the sarcoplasmic reticulum of working muscle. Proc Natl Acad Sci U S A 2017; 114:E638-E647. [PMID: 28069951 DOI: 10.1073/pnas.1620265114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Calsequestrin, the only known protein with cyclical storage and supply of calcium as main role, is proposed to have other functions, which remain unproven. Voluntary movement and the heart beat require this calcium flow to be massive and fast. How does calsequestrin do it? To bind large amounts of calcium in vitro, calsequestrin must polymerize and then depolymerize to release it. Does this rule apply inside the sarcoplasmic reticulum (SR) of a working cell? We answered using fluorescently tagged calsequestrin expressed in muscles of mice. By FRAP and imaging we monitored mobility of calsequestrin as [Ca2+] in the SR--measured with a calsequestrin-fused biosensor--was lowered. We found that calsequestrin is polymerized within the SR at rest and that it depolymerized as [Ca2+] went down: fully when calcium depletion was maximal (a condition achieved with an SR calcium channel opening drug) and partially when depletion was limited (a condition imposed by fatiguing stimulation, long-lasting depolarization, or low drug concentrations). With fluorescence and electron microscopic imaging we demonstrated massive movements of calsequestrin accompanied by drastic morphological SR changes in fully depleted cells. When cells were partially depleted no remodeling was found. The present results support the proposed role of calsequestrin in termination of calcium release by conformationally inducing closure of SR channels. A channel closing switch operated by calsequestrin depolymerization will limit depletion, thereby preventing full disassembly of the polymeric calsequestrin network and catastrophic structural changes in the SR.
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29
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The Endoplasmic Reticulum and the Cellular Reticular Network. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 981:61-76. [DOI: 10.1007/978-3-319-55858-5_4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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30
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Characterization of Post-Translational Modifications to Calsequestrins of Cardiac and Skeletal Muscle. Int J Mol Sci 2016; 17:ijms17091539. [PMID: 27649144 PMCID: PMC5037814 DOI: 10.3390/ijms17091539] [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] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 09/05/2016] [Accepted: 09/08/2016] [Indexed: 11/26/2022] Open
Abstract
Calsequestrin is glycosylated and phosphorylated during its transit to its final destination in the junctional sarcoplasmic reticulum. To determine the significance and universal profile of these post-translational modifications to mammalian calsequestrin, we characterized, via mass spectrometry, the glycosylation and phosphorylation of skeletal muscle calsequestrin from cattle (B. taurus), lab mice (M. musculus) and lab rats (R. norvegicus) and cardiac muscle calsequestrin from cattle, lab rats and humans. On average, glycosylation of skeletal calsequestrin consisted of two N-acetylglucosamines and one mannose (GlcNAc2Man1), while cardiac calsequestrin had five additional mannoses (GlcNAc2Man6). Skeletal calsequestrin was not phosphorylated, while the C-terminal tails of cardiac calsequestrin contained between zero to two phosphoryls, indicating that phosphorylation of cardiac calsequestrin may be heterogeneous in vivo. Static light scattering experiments showed that the Ca2+-dependent polymerization capabilities of native bovine skeletal calsequestrin are enhanced, relative to the non-glycosylated, recombinant isoform, which our crystallographic studies suggest may be due to glycosylation providing a dynamic “guiderail”-like scaffold for calsequestrin polymerization. Glycosylation likely increases a polymerization/depolymerization response to changing Ca2+ concentrations, and proper glycosylation, in turn, guarantees both effective Ca2+ storage/buffering of the sarcoplasmic reticulum and localization of calsequestrin (Casq) at its target site.
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31
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Treves S, Jungbluth H, Voermans N, Muntoni F, Zorzato F. Ca 2+ handling abnormalities in early-onset muscle diseases: Novel concepts and perspectives. Semin Cell Dev Biol 2016; 64:201-212. [PMID: 27427513 DOI: 10.1016/j.semcdb.2016.07.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 07/14/2016] [Indexed: 12/17/2022]
Abstract
The physiological process by which Ca2+ is released from the sarcoplasmic reticulum is called excitation-contraction coupling; it is initiated by an action potential which travels deep into the muscle fiber where it is sensed by the dihydropyridine receptor, a voltage sensing L-type Ca2+channel localized on the transverse tubules. Voltage-induced conformational changes in the dihydropyridine receptor activate the ryanodine receptor Ca2+ release channel of the sarcoplasmic reticulum. The released Ca2+ binds to troponin C, enabling contractile thick-thin filament interactions. The Ca2+ is subsequently transported back into the sarcoplasmic reticulum by specialized Ca2+ pumps (SERCA), preparing the muscle for a new cycle of contraction. Although other proteins are involved in excitation-contraction coupling, the mechanism described above emphasizes the unique role played by the two Ca2+ channels (the dihydropyridine receptor and the ryanodine receptor), the SERCA Ca2+ pumps and the exquisite spatial organization of the membrane compartments endowed with the proteins responsible for this mechanism to function rapidly and efficiently. Research over the past two decades has uncovered the fine details of excitation-contraction coupling under normal conditions while advances in genomics have helped to identify mutations in novel genes in patients with neuromuscular disorders. While it is now clear that many patients with congenital muscle diseases carry mutations in genes encoding proteins directly involved in Ca2+ homeostasis, it has become apparent that mutations are also present in genes encoding for proteins not thought to be directly involved in Ca2+ regulation. Ongoing research in the field now focuses on understanding the functional effect of individual mutations, as well as understanding the role of proteins not specifically located in the sarcoplasmic reticulum which nevertheless are involved in Ca2+ regulation or excitation-contraction coupling. The principal challenge for the future is the identification of drug targets that can be pharmacologically manipulated by small molecules, with the ultimate aim to improve muscle function and quality of life of patients with congenital muscle disorders. The aim of this review is to give an overview of the most recent findings concerning Ca2+ dysregulation and its impact on muscle function in patients with congenital muscle disorders due to mutations in proteins involved in excitation-contraction coupling and more broadly on Ca2+ homeostasis.
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Affiliation(s)
- Susan Treves
- Departments of Biomedicine and Anesthesia, Basel University Hospital, 4031 Basel, Switzerland; Department of Life Sciences, General Pathology Section, University of Ferrara, 44100 Ferrara, Italy.
| | - Heinz Jungbluth
- Department of Paediatric Neurology, Neuromuscular Service, Evelina Children's Hospital, St. Thomas' Hospital, London, United Kingdom; Randall Division for Cell and Molecular Biophysics, Muscle Signalling Section, King's College, London, United Kingdom; Department of Basic and Clinical Neuroscience, IoPPN, King's College, London, United Kingdom
| | - Nicol Voermans
- Department of Neurology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, Institute of Child Health, University College London, United Kingdom
| | - Francesco Zorzato
- Departments of Biomedicine and Anesthesia, Basel University Hospital, 4031 Basel, Switzerland; Department of Life Sciences, General Pathology Section, University of Ferrara, 44100 Ferrara, Italy
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Willis BC, Pandit SV, Ponce-Balbuena D, Zarzoso M, Guerrero-Serna G, Limbu B, Deo M, Camors E, Ramirez RJ, Mironov S, Herron TJ, Valdivia HH, Jalife J. Constitutive Intracellular Na+ Excess in Purkinje Cells Promotes Arrhythmogenesis at Lower Levels of Stress Than Ventricular Myocytes From Mice With Catecholaminergic Polymorphic Ventricular Tachycardia. Circulation 2016; 133:2348-59. [PMID: 27169737 PMCID: PMC4902321 DOI: 10.1161/circulationaha.116.021936] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 05/03/2016] [Indexed: 11/18/2022]
Abstract
Supplemental Digital Content is available in the text. Background— In catecholaminergic polymorphic ventricular tachycardia (CPVT), cardiac Purkinje cells (PCs) appear more susceptible to Ca2+ dysfunction than ventricular myocytes (VMs). The underlying mechanisms remain unknown. Using a CPVT mouse (RyR2R4496C+/Cx40eGFP), we tested whether PC intracellular Ca2+ ([Ca2+]i) dysregulation results from a constitutive [Na+]i surplus relative to VMs. Methods and Results— Simultaneous optical mapping of voltage and [Ca2+]i in CPVT hearts showed that spontaneous Ca2+ release preceded pacing-induced triggered activity at subendocardial PCs. On simultaneous current-clamp and Ca2+ imaging, early and delayed afterdepolarizations trailed spontaneous Ca2+ release and were more frequent in CPVT PCs than CPVT VMs. As a result of increased activity of mutant ryanodine receptor type 2 channels, sarcoplasmic reticulum Ca2+ load, measured by caffeine-induced Ca2+ transients, was lower in CPVT VMs and PCs than respective controls, and sarcoplasmic reticulum fractional release was greater in both CPVT PCs and VMs than respective controls. [Na+]i was higher in both control and CPVT PCs than VMs, whereas the density of the Na+/Ca2+ exchanger current was not different between PCs and VMs. Computer simulations using a PC model predicted that the elevated [Na+]i of PCs promoted delayed afterdepolarizations, which were always preceded by spontaneous Ca2+ release events from hyperactive ryanodine receptor type 2 channels. Increasing [Na+]i monotonically increased delayed afterdepolarization frequency. Confocal imaging experiments showed that postpacing Ca2+ spark frequency was highest in intact CPVT PCs, but such differences were reversed on saponin-induced membrane permeabilization, indicating that differences in [Na+]i played a central role. Conclusions— In CPVT mice, the constitutive [Na+]i excess of PCs promotes triggered activity and arrhythmogenesis at lower levels of stress than VMs.
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Affiliation(s)
- B Cicero Willis
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Sandeep V Pandit
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Daniela Ponce-Balbuena
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Manuel Zarzoso
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Guadalupe Guerrero-Serna
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Bijay Limbu
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Makarand Deo
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Emmanuel Camors
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Rafael J Ramirez
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Sergey Mironov
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Todd J Herron
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - Héctor H Valdivia
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.)
| | - José Jalife
- From University of Michigan, Ann Arbor (B.C.W., S.V.P., D.P.-B., M.Z., G.G.-S., R.J.R., S.M., T.J.H., H.H.V., J.J.); Norfolk State University, VA (B.L., M.D.); University of Tennessee Health Science Center, Memphis (E.C.); and Fundación Centro Nacional de Investigaciones Cardiovasculares, Madrid, Spain (J.J.).
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Basaki M, Asasi K, Tabandeh MR, Aminlari M. Polymorphism identification and cardiac gene expression analysis of the calsequestrin 2 gene in broiler chickens with sudden death syndrome. Br Poult Sci 2016; 57:151-60. [DOI: 10.1080/00071668.2015.1099615] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Ríos E, Figueroa L, Manno C, Kraeva N, Riazi S. The couplonopathies: A comparative approach to a class of diseases of skeletal and cardiac muscle. ACTA ACUST UNITED AC 2016; 145:459-74. [PMID: 26009541 PMCID: PMC4442791 DOI: 10.1085/jgp.201411321] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A novel category of diseases of striated muscle is proposed, the couplonopathies, as those that affect components of the couplon and thereby alter its operation. Couplons are the functional units of intracellular calcium release in excitation–contraction coupling. They comprise dihydropyridine receptors, ryanodine receptors (Ca2+ release channels), and a growing list of ancillary proteins whose alteration may lead to disease. Within a generally similar plan, the couplons of skeletal and cardiac muscle show, in a few places, marked structural divergence associated with critical differences in the mechanisms whereby they fulfill their signaling role. Most important among these are the presence of a mechanical or allosteric communication between voltage sensors and Ca2+ release channels, exclusive to the skeletal couplon, and the smaller capacity of the Ca stores in cardiac muscle, which results in greater swings of store concentration during physiological function. Consideration of these structural and functional differences affords insights into the pathogenesis of several couplonopathies. The exclusive mechanical connection of the skeletal couplon explains differences in pathogenesis between malignant hyperthermia (MH) and catecholaminergic polymorphic ventricular tachycardia (CPVT), conditions most commonly caused by mutations in homologous regions of the skeletal and cardiac Ca2+ release channels. Based on mechanistic considerations applicable to both couplons, we identify the plasmalemma as a site of secondary modifications, typically an increase in store-operated calcium entry, that are relevant in MH pathogenesis. Similar considerations help explain the different consequences that mutations in triadin and calsequestrin have in these two tissues. As more information is gathered on the composition of cardiac and skeletal couplons, this comparative and mechanistic approach to couplonopathies should be useful to understand pathogenesis, clarify diagnosis, and propose tissue-specific drug development.
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Affiliation(s)
- Eduardo Ríos
- Section of Cellular Signaling, Department of Molecular Biophysics and Physiology, Rush University, Chicago, IL 60612
| | - Lourdes Figueroa
- Section of Cellular Signaling, Department of Molecular Biophysics and Physiology, Rush University, Chicago, IL 60612
| | - Carlo Manno
- Section of Cellular Signaling, Department of Molecular Biophysics and Physiology, Rush University, Chicago, IL 60612
| | - Natalia Kraeva
- Malignant Hyperthermia Investigation Unit, University Health Network, Toronto General Hospital, Toronto, Ontario M5G 2C4, Canada
| | - Sheila Riazi
- Malignant Hyperthermia Investigation Unit, University Health Network, Toronto General Hospital, Toronto, Ontario M5G 2C4, Canada
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35
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Patel BB, Raad M, Sebag IA, Chalifour LE. Sex-specific cardiovascular responses to control or high fat diet feeding in C57bl/6 mice chronically exposed to bisphenol A. Toxicol Rep 2015; 2:1310-1318. [PMID: 28962473 PMCID: PMC5598525 DOI: 10.1016/j.toxrep.2015.09.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 09/25/2015] [Indexed: 12/16/2022] Open
Abstract
The increased pericardial fat which often accompanies overall obesity is thought to alter cardiac structure/function and increase the risk for atrial fibrillation. We hypothesized that chronic exposure to bisphenol A (BPA) would induce pericardial fat, cardiac hypertrophy or arrhythmia. C57bl/6n dams were exposed to BPA (25 ng/ml drinking water) beginning on gestation day 11 and progeny continued on 2.5 ng BPA/ml drinking water. The progeny of control dams (VEH) and dams treated with diethylstilbestrol (DES, 1 μg/kg/day, gestation days 1114) had tap water. After weaning progeny were fed either a control (CD) or high fat diet (HFD) for 3 months. Pericardial fat was present in CD-BPA and CD-DES and not CD-VEH mice, and was increased in all HFD mice. Catecholamine challenge revealed no differences in males, but BPA-exposed females had longer P-wave and QRS complex duration. Only CD-BPA and CD-DES females developed cardiac hypertrophy which was independent of increased blood pressure. Calcium homeostasis protein expression changes in HFD-BPA and HFD-DES mice predict reduced SERCA2 activity in males and increased SERCA2 activity in females. Thus, chronic BPA exposure induced pericardial fat in the absence of HFD, and female-specific changes in cardiac hypertrophy development and cardiac electrical conduction after a catecholamine challenge.
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Affiliation(s)
- Bhavini B Patel
- Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montreal, Quebec H3T 1E2, Canada
| | - Mohamad Raad
- Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montreal, Quebec H3T 1E2, Canada
| | - Igal A Sebag
- Division of Cardiology, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montreal, Quebec H3T 1E2, Canada
| | - Lorraine E Chalifour
- Lady Davis Institute for Medical Research, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montreal, Quebec H3T 1E2, Canada.,Division of Cardiology, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montreal, Quebec H3T 1E2, Canada.,Division of Endocrinology, Jewish General Hospital, 3755 chemin Cote Ste Catherine, Montréal, Québec H3T 1E2, Canada.,Division of Experimental Medicine, Department of Medicine, McGill University, 850 Sherbrooke Street, Montréal, Québec H3A 1A2, Canada
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36
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Novak A, Barad L, Lorber A, Gherghiceanu M, Reiter I, Eisen B, Eldor L, Itskovitz-Eldor J, Eldar M, Arad M, Binah O. Functional abnormalities in iPSC-derived cardiomyocytes generated from CPVT1 and CPVT2 patients carrying ryanodine or calsequestrin mutations. J Cell Mol Med 2015; 19:2006-18. [PMID: 26153920 PMCID: PMC4549051 DOI: 10.1111/jcmm.12581] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 02/17/2015] [Indexed: 01/11/2023] Open
Abstract
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is an inherited arrhythmia characterized by syncope and sudden death occurring during exercise or acute emotion. CPVT is caused by abnormal intracellular Ca2+ handling resulting from mutations in the RyR2 or CASQ2 genes. Because CASQ2 and RyR2 are involved in different aspects of the excitation-contraction coupling process, we hypothesized that these mutations are associated with different functional and intracellular Ca²+ abnormalities. To test the hypothesis we generated induced Pluripotent Stem Cell-derived cardiomyocytes (iPSC-CM) from CPVT1 and CPVT2 patients carrying the RyR2R420Q and CASQ2D307H mutations, respectively, and investigated in CPVT1 and CPVT2 iPSC-CM (compared to control): (i) The ultrastructural features; (ii) the effects of isoproterenol, caffeine and ryanodine on the [Ca2+]i transient characteristics. Our major findings were: (i) Ultrastructurally, CASQ2 and RyR2 mutated cardiomyocytes were less developed than control cardiomyocytes. (ii) While in control iPSC-CM isoproterenol caused positive inotropic and lusitropic effects, in the mutated cardiomyocytes isoproterenol was either ineffective, caused arrhythmias, or markedly increased diastolic [Ca2+]i. Importantly, positive inotropic and lusitropic effects were not induced in mutated cardiomyocytes. (iii) The effects of caffeine and ryanodine in mutated cardiomyocytes differed from control cardiomyocytes. Our results show that iPSC-CM are useful for investigating the similarities/differences in the pathophysiological consequences of RyR2 versus CASQ2 mutations underlying CPVT1 and CPVT2 syndromes.
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Affiliation(s)
- Atara Novak
- Department of Physiology, Technion, Haifa, Israel.,The Rappaport Institute for Research in the Medical Sciences, Technion, Haifa, Israel.,Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Lili Barad
- Department of Physiology, Technion, Haifa, Israel.,The Rappaport Institute for Research in the Medical Sciences, Technion, Haifa, Israel.,Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Avraham Lorber
- Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel.,Department of Pediatric Cardiology, Rambam Health Care Campus, Haifa, Israel
| | | | - Irina Reiter
- Department of Physiology, Technion, Haifa, Israel.,The Rappaport Institute for Research in the Medical Sciences, Technion, Haifa, Israel.,Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Binyamin Eisen
- Department of Physiology, Technion, Haifa, Israel.,The Rappaport Institute for Research in the Medical Sciences, Technion, Haifa, Israel.,Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Liron Eldor
- Department of Plastic Surgery, Rambam Health Care Campus, Haifa, Israel
| | - Joseph Itskovitz-Eldor
- The Rappaport Institute for Research in the Medical Sciences, Technion, Haifa, Israel.,Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
| | - Michael Eldar
- Leviev Heart Center, Sheba Medical Center, Tel Hashomer and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Michael Arad
- Leviev Heart Center, Sheba Medical Center, Tel Hashomer and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ofer Binah
- Department of Physiology, Technion, Haifa, Israel.,The Rappaport Institute for Research in the Medical Sciences, Technion, Haifa, Israel.,Ruth & Bruce Rappaport Faculty of Medicine, Technion, Haifa, Israel
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37
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Zhang JZ, Waddell HMM, Jones PP. Regulation of RYR2 by sarcoplasmic reticulum Ca(2+). Clin Exp Pharmacol Physiol 2015; 42:720-6. [PMID: 25603835 DOI: 10.1111/1440-1681.12364] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 09/17/2014] [Accepted: 10/09/2014] [Indexed: 11/28/2022]
Abstract
Ca(2+) is arguably the most important ion involved in the contraction of the heart. The cardiac ryanodine receptor (RyR2), the major Ca(2+) release channel located in the sarcoplasmic reticulum (SR) membrane, is responsible for releasing the bulk of Ca(2+) required for contraction. Moreover, RyR2 is also crucial for maintaining SR Ca(2+) homeostasis by releasing Ca(2+) from the SR when it becomes overloaded with Ca(2+) . During normal contraction, RyR2 is activated by cytosolic Ca(2+) , whereas during store overload conditions, the opening of RyR2 is governed by SR Ca(2+) . Although the process of the cytosolic control of RyR2 is well established, the molecular mechanism by which SR luminal Ca(2+) regulates RyR2 has only recently been elucidated and remains controversial. In addition to the activation of RyR2, SR luminal Ca(2+) also determines when the RyR2 channel closes. RyR2-mediated Ca(2+) release from the SR does not continue until the SR is completely depleted. Rather, it ceases when SR luminal Ca(2+) falls below a certain level. Given the importance of SR Ca(2+) , it is not surprising that the SR luminal Ca(2+) level is tightly controlled by SR Ca(2+) -buffering proteins. Consequently, the opening and closing of RyR2 is heavily influenced by the presence of such proteins, particularly those associated with RyR2, such as calsequestrin and the histidine-rich Ca(2+) -binding protein. These proteins appear to indirectly alter RyR2 activity by modifying the microdomain SR Ca(2+) level surrounding RyR2.
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Affiliation(s)
- Joe Z Zhang
- Department of Physiology and HeartOtago, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Helen M M Waddell
- Department of Physiology and HeartOtago, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
| | - Peter P Jones
- Department of Physiology and HeartOtago, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand
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38
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Li L, Mirza S, Richardson SJ, Gallant EM, Thekkedam C, Pace SM, Zorzato F, Liu D, Beard NA, Dulhunty AF. A new cytoplasmic interaction between junctin and ryanodine receptor Ca2+ release channels. J Cell Sci 2015; 128:951-63. [PMID: 25609705 PMCID: PMC4342579 DOI: 10.1242/jcs.160689] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Junctin, a non-catalytic splice variant encoded by the aspartate-β-hydroxylase (Asph) gene, is inserted into the membrane of the sarcoplasmic reticulum (SR) Ca2+ store where it modifies Ca2+ signalling in the heart and skeletal muscle through its regulation of ryanodine receptor (RyR) Ca2+ release channels. Junctin is required for normal muscle function as its knockout leads to abnormal Ca2+ signalling, muscle dysfunction and cardiac arrhythmia. However, the nature of the molecular interaction between junctin and RyRs is largely unknown and was assumed to occur only in the SR lumen. We find that there is substantial binding of RyRs to full junctin, and the junctin luminal and, unexpectedly, cytoplasmic domains. Binding of these different junctin domains had distinct effects on RyR1 and RyR2 activity: full junctin in the luminal solution increased RyR channel activity by ∼threefold, the C-terminal luminal interaction inhibited RyR channel activity by ∼50%, and the N-terminal cytoplasmic binding produced an ∼fivefold increase in RyR activity. The cytoplasmic interaction between junctin and RyR is required for luminal binding to replicate the influence of full junctin on RyR1 and RyR2 activity. The C-terminal domain of junctin binds to residues including the S1–S2 linker of RyR1 and N-terminal domain of junctin binds between RyR1 residues 1078 and 2156.
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Affiliation(s)
- Linwei Li
- John Curtin School of Medical Research, ACT 0200, Australia
| | - Shamaruh Mirza
- John Curtin School of Medical Research, ACT 0200, Australia
| | | | | | | | - Suzy M Pace
- John Curtin School of Medical Research, ACT 0200, Australia
| | | | - Dan Liu
- John Curtin School of Medical Research, ACT 0200, Australia
| | - Nicole A Beard
- John Curtin School of Medical Research, ACT 0200, Australia
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39
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Deo RC, Musso G, Tasan M, Tang P, Poon A, Yuan C, Felix JF, Vasan RS, Beroukhim R, De Marco T, Kwok PY, MacRae CA, Roth FP. Prioritizing causal disease genes using unbiased genomic features. Genome Biol 2014; 15:534. [PMID: 25633252 PMCID: PMC4279789 DOI: 10.1186/s13059-014-0534-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 11/06/2014] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Cardiovascular disease (CVD) is the leading cause of death in the developed world. Human genetic studies, including genome-wide sequencing and SNP-array approaches, promise to reveal disease genes and mechanisms representing new therapeutic targets. In practice, however, identification of the actual genes contributing to disease pathogenesis has lagged behind identification of associated loci, thus limiting the clinical benefits. RESULTS To aid in localizing causal genes, we develop a machine learning approach, Objective Prioritization for Enhanced Novelty (OPEN), which quantitatively prioritizes gene-disease associations based on a diverse group of genomic features. This approach uses only unbiased predictive features and thus is not hampered by a preference towards previously well-characterized genes. We demonstrate success in identifying genetic determinants for CVD-related traits, including cholesterol levels, blood pressure, and conduction system and cardiomyopathy phenotypes. Using OPEN, we prioritize genes, including FLNC, for association with increased left ventricular diameter, which is a defining feature of a prevalent cardiovascular disorder, dilated cardiomyopathy or DCM. Using a zebrafish model, we experimentally validate FLNC and identify a novel FLNC splice-site mutation in a patient with severe DCM. CONCLUSION Our approach stands to assist interpretation of large-scale genetic studies without compromising their fundamentally unbiased nature.
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Affiliation(s)
- Rahul C Deo
- />Cardiovascular Research Institute, University of California, San Francisco, CA 94158 USA
- />Department of Medicine, University of California, San Francisco, CA 94143 USA
- />Institute for Human Genetics, University of California, San Francisco, CA 94158 USA
- />California Institute for Quantitative Biosciences, San Francisco, CA 94143 USA
- />Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115 USA
| | - Gabriel Musso
- />Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115 USA
- />Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115 USA
| | - Murat Tasan
- />Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115 USA
- />Donnelly Centre and Departments of Molecular Genetics and Computer Science, University of Toronto and Lunenfeld Research Institute, Mt Sinai Hospital, Toronto, Ontario M5G 1X5 Canada
| | - Paul Tang
- />Institute for Human Genetics, University of California, San Francisco, CA 94158 USA
| | - Annie Poon
- />Institute for Human Genetics, University of California, San Francisco, CA 94158 USA
| | - Christiana Yuan
- />Cardiovascular Research Institute, University of California, San Francisco, CA 94158 USA
| | - Janine F Felix
- />Department of Epidemiology, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Ramachandran S Vasan
- />Preventive Medicine and Cardiology Sections, and Department of Medicine, Boston University School of Medicine, Boston, MA 02118 USA
- />Framingham Heart Study, Boston University School of Medicine, Framingham, MA 01702 USA
| | - Rameen Beroukhim
- />Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115 USA
- />Center for Cancer Genome Discovery and Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215 USA
| | - Teresa De Marco
- />Department of Medicine, University of California, San Francisco, CA 94143 USA
| | - Pui-Yan Kwok
- />Cardiovascular Research Institute, University of California, San Francisco, CA 94158 USA
- />Institute for Human Genetics, University of California, San Francisco, CA 94158 USA
| | - Calum A MacRae
- />Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115 USA
| | - Frederick P Roth
- />Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115 USA
- />Donnelly Centre and Departments of Molecular Genetics and Computer Science, University of Toronto and Lunenfeld Research Institute, Mt Sinai Hospital, Toronto, Ontario M5G 1X5 Canada
- />Center for Cancer Systems Biology (CCSB) and Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215 USA
- />The Canadian Institute for Advanced Research, Toronto, ON M5G 1Z8 Canada
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Ma X, Barboza LA, Siyahian A, Reinhartz O, Maeda K, Reddy VM, Hanley FL, Riemer RK. Tetralogy of Fallot: aorto-pulmonary collaterals and pulmonary arteries have distinctly different transcriptomes. Pediatr Res 2014; 76:341-6. [PMID: 25000348 DOI: 10.1038/pr.2014.101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 04/14/2014] [Indexed: 11/09/2022]
Abstract
BACKGROUND Tetralogy of Fallot patients with pulmonary atresia (TOF/PA) present a pulmonary blood supply directly from aortic collateral arteries. Major aorto-pulmonary collateral arteries (MAPCAs) present substantial clinical and surgical management challenges. Surgical operations to reestablish and promote further development of a pulmonary arterial connection preferentially utilize MAPCAs for reconstruction of central pulmonary arteries. However, the propensity of some MAPCAs to develop stenosis rather than growth may impair the response to reconstructions. METHODS Probe sets prepared from MAPCAs, PA, and aorta mRNA were used to interrogate human genome microarrays. We compared expression differences between pairs of the three vessels to determine whether MAPCAs display distinct expression patterns. RESULTS Functional clustering analysis identified differences in gene expression, which were further analyzed by gene ontology classification. A subset of highly regulated genes was validated using quantitative PCR. Expression differences among vessel types were observed for multiple gene classes. Of note, we observed that MAPCAs differentially express several genes at much higher levels than either PA or aorta. CONCLUSION MAPCAs differ from PA or aorta by significantly altered levels in gene expression, suggesting a transcriptional basis for their physiology that will guide a further understanding of the pathobiology of MAPCAs and TOF.
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Affiliation(s)
- Xiaoyuan Ma
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Laura A Barboza
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Arpi Siyahian
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Olaf Reinhartz
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Katsuhide Maeda
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | | | - Frank L Hanley
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
| | - Robert Kirk Riemer
- Department of Cardiothoracic Surgery, Stanford University, Stanford, California
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41
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Zhang JZ, McLay JC, Jones PP. The arrhythmogenic human HRC point mutation S96A leads to spontaneous Ca2+ release due to an impaired ability to buffer store Ca2+. J Mol Cell Cardiol 2014; 74:22-31. [DOI: 10.1016/j.yjmcc.2014.04.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/14/2014] [Accepted: 04/28/2014] [Indexed: 11/26/2022]
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42
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Nerbonne JM. Mouse models of arrhythmogenic cardiovascular disease: challenges and opportunities. Curr Opin Pharmacol 2014; 15:107-14. [PMID: 24632325 DOI: 10.1016/j.coph.2014.02.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 02/04/2014] [Accepted: 02/05/2014] [Indexed: 12/27/2022]
Abstract
Arrhythmogenic cardiovascular disease is associated with significant morbidity and mortality and, in spite of therapeutic advances, remains an enormous public health burden. The scope of this problem motivates efforts to delineate the molecular, cellular and systemic mechanisms underlying increased arrhythmia risk in inherited and acquired cardiac and systemic disease. The mouse is used increasingly in these efforts owing to the ease with which genetic strategies can be exploited and mechanisms can be probed. The question then arises whether the mouse has proven to be a useful model system to delineate arrhythmogenic cardiovascular disease mechanisms. Rather than trying to provide a definite answer, the goal here is to consider the issues that arise when using mouse models and to highlight the opportunities.
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Affiliation(s)
- Jeanne M Nerbonne
- Department of Developmental Biology, Washington University Medical School, St. Louis, MO 63110, USA; Department of Internal Medicine, Washington University Medical School, St. Louis, MO 63110, USA.
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43
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Refaat MM, Aouizerat BE, Pullinger CR, Malloy M, Kane J, Tseng ZH. Association of CASQ2 polymorphisms with sudden cardiac arrest and heart failure in patients with coronary artery disease. Heart Rhythm 2014; 11:646-52. [PMID: 24444446 DOI: 10.1016/j.hrthm.2014.01.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Abnormal calcium handling plays a crucial role in arrhythmias, sudden cardiac arrest (SCA), and congestive heart failure (CHF). Calsequestrin 2 (CASQ2) mutations affect calcium release and initiate malignant ventricular arrhythmias (VAs) and SCA syndromes. Common single nucleotide polymorphisms (SNPs) in CASQ2 may be associated with SCA in patients with coronary artery disease (CAD). OBJECTIVE The purpose of this study was to examine the association of common CASQ2 SNPs with the risk of SCA in patients with CAD. METHODS CASQ2 SNPs (n = 14) were genotyped and analyzed in a case control study comparing 114 patients with CAD and SCA due to VA to 311 CAD controls without VA or SCA. RESULTS Multivariate logistic regression adjusting for age and CHF status identified an association between rs7521023 with SCA (odds ratio [OR] 2.72, 95% confidence interval [CI] 1.44-5.13, P = .002). The substantial impact of CHF on SCA in the model (OR 26.6, 95% CI 13.40-52.70, P <.001) led us to further examine the relationship between CHF, SCA, and CASQ2 SNPs. We identified 2 CASQ2 variants (rs7521023: OR 0.4, 95% CI 0.25-0.76, P = .003; rs6684209: OR 19.8, 95% CI 3.63-108.2, P <.001) associated with CHF after adjusting for SCA, age, gender, and hypertension. CONCLUSION We observed association between a CASQ2 polymorphism and SCA due to VA in patients with CAD adjusting for CHF and independent associations between CASQ2 SNPs and CHF adjusting for SCA. Further investigation in independent cohorts is needed to confirm these findings.
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Affiliation(s)
- Marwan M Refaat
- Department of Internal Medicine, Cardiovascular Medicine/Cardiac Electrophysiology, American University of Beirut Faculty of Medicine, Beirut, Lebanon
| | | | - Clive R Pullinger
- Cardiovascular Research Institute, University of California, San Francisco, California
| | - Mary Malloy
- Cardiovascular Research Institute, University of California, San Francisco, California
| | - John Kane
- Cardiovascular Research Institute, University of California, San Francisco, California
| | - Zian H Tseng
- Section of Cardiac Electrophysiology, Department of Medicine.
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Glukhov AV, Kalyanasundaram A, Lou Q, Hage LT, Hansen BJ, Belevych AE, Mohler PJ, Knollmann BC, Periasamy M, Györke S, Fedorov VV. Calsequestrin 2 deletion causes sinoatrial node dysfunction and atrial arrhythmias associated with altered sarcoplasmic reticulum calcium cycling and degenerative fibrosis within the mouse atrial pacemaker complex1. Eur Heart J 2013; 36:686-97. [PMID: 24216388 DOI: 10.1093/eurheartj/eht452] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
AIMS Loss-of-function mutations in Calsequestrin 2 (CASQ2) are associated with catecholaminergic polymorphic ventricular tachycardia (CPVT). CPVT patients also exhibit bradycardia and atrial arrhythmias for which the underlying mechanism remains unknown. We aimed to study the sinoatrial node (SAN) dysfunction due to loss of CASQ2. METHODS AND RESULTS In vivo electrocardiogram (ECG) monitoring, in vitro high-resolution optical mapping, confocal imaging of intracellular Ca(2+) cycling, and 3D atrial immunohistology were performed in wild-type (WT) and Casq2 null (Casq2(-/-)) mice. Casq2(-/-) mice exhibited bradycardia, SAN conduction abnormalities, and beat-to-beat heart rate variability due to enhanced atrial ectopic activity both at baseline and with autonomic stimulation. Loss of CASQ2 increased fibrosis within the pacemaker complex, depressed primary SAN activity, and conduction, but enhanced atrial ectopic activity and atrial fibrillation (AF) associated with macro- and micro-reentry during autonomic stimulation. In SAN myocytes, CASQ2 deficiency induced perturbations in intracellular Ca(2+) cycling, including abnormal Ca(2+) release, periods of significantly elevated diastolic Ca(2+) levels leading to pauses and unstable pacemaker rate. Importantly, Ca(2+) cycling dysfunction occurred not only at the SAN cellular level but was also globally manifested as an increased delay between action potential (AP) and Ca(2+) transient upstrokes throughout the atrial pacemaker complex. CONCLUSIONS Loss of CASQ2 causes abnormal sarcoplasmic reticulum Ca(2+) release and selective interstitial fibrosis in the atrial pacemaker complex, which disrupt SAN pacemaking but enhance latent pacemaker activity, create conduction abnormalities and increase susceptibility to AF. These functional and extensive structural alterations could contribute to SAN dysfunction as well as AF in CPVT patients.
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Affiliation(s)
- Alexey V Glukhov
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Anuradha Kalyanasundaram
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Qing Lou
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Lori T Hage
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Brian J Hansen
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Andriy E Belevych
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Peter J Mohler
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Björn C Knollmann
- Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Muthu Periasamy
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Sandor Györke
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
| | - Vadim V Fedorov
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Medical Center, Columbus, OH, USA
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Jabbari J, Jabbari R, Nielsen MW, Holst AG, Nielsen JB, Haunsø S, Tfelt-Hansen J, Svendsen JH, Olesen MS. New Exome Data Question the Pathogenicity of Genetic Variants Previously Associated With Catecholaminergic Polymorphic Ventricular Tachycardia. ACTA ACUST UNITED AC 2013; 6:481-9. [DOI: 10.1161/circgenetics.113.000118] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Background—
Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a lethal, rare hereditary disease with an estimated prevalence of 1:10 000. The genetic variants that cause CPVT are usually highly penetrant. To date, about 189 variants in 5 genes (
RYR2, CASQ2, CALM1, TRND
, and
KCNJ2
) have been associated with CPVT pathogenesis.
Methods and Results—
The Exome Sequencing Project database (ESP; n= 6503) was systematically searched for previously published missense and nonsense CPVT–associated variants reported in several comprehensive reviews and in 2 databases: The Human Gene Mutation Database and The Inherited Arrhythmias Database. We used 4 different prediction tools to assess all missense variants previously associated with CPVT and compared the prediction of protein damage between CPVT-associated variants identified in the ESP and those variants not identified in the ESP. We identified 11% of the variants previously associated with CPVT in the ESP population. In the literature, 57% of these variants were reported as novel disease-causing variants absent in the healthy control subjects. These putative CPVT variants were identified in 41 out of 6131 subjects in the ESP population, corresponding to a prevalence of CPVT of up to 1:150. Using an agreement of ≥3, in silico prediction tools showed a significantly higher frequency of damaging variants among the CPVT-associated variants not identified in the ESP database (83%) compared with those variants identified in the ESP (50%;
P
=0.021).
Conclusions—
We identified a substantial overrepresentation of CPVT-associated variants in a large exome database, suggesting that these variants are not necessarily the monogenic cause of CPVT.
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Affiliation(s)
- Javad Jabbari
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Reza Jabbari
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Morten W. Nielsen
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Anders G. Holst
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Jonas B. Nielsen
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Stig Haunsø
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Jacob Tfelt-Hansen
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Jesper H. Svendsen
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
| | - Morten S. Olesen
- From the Danish National Research Foundation Centre for Cardiac Arrhythmia (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); Laboratory for Molecular Cardiology, The Heart Centre, Rigshospitalet, Copenhagen University Hospital (J.J., R.J., M.W.N., A.G.H., J.B.N., S.H., J.T.-H., J.H.S., M.S.O.); and Department of Clinical Medicine, Faculty of Health Sciences (S.H., J.T.-H., J.H.S.), University of Copenhagen, Copenhagen, Denmark
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Gaburjakova M, Bal NC, Gaburjakova J, Periasamy M. Functional interaction between calsequestrin and ryanodine receptor in the heart. Cell Mol Life Sci 2013; 70:2935-45. [PMID: 23109100 PMCID: PMC11113811 DOI: 10.1007/s00018-012-1199-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 10/02/2012] [Accepted: 10/15/2012] [Indexed: 11/25/2022]
Abstract
Evidence obtained in the last two decades indicates that calsequestrin (CSQ2), as the major Ca(2+)-binding protein in the sarcoplasmic reticulum of cardiac myocytes, communicates changes in the luminal Ca(2+) concentration to the cardiac ryanodine receptor (RYR2) channel. This review summarizes the major aspects in the interaction between CSQ2 and the RYR2 channel. The single channel properties of RYR2 channels, discussed here in the context of structural changes in CSQ2 after Ca(2+) binding, are particularly important. We focus on five important questions concerning: (1) the method for reliable detection of CSQ2 on the reconstituted RYR2 channel complex; (2) the power of the procedure to strip CSQ2 from the RYR2 channel complex; (3) structural changes in CSQ2 upon binding of Ca(2+) which cause CSQ2 dissociation; (4) the potential role of CSQ2-independent regulation of the RYR2 activity by luminal Ca(2+); and (5) the vizualization of CSQ2 dissociation from the RYR2 channel complex on the single channel level. We discuss the potential sources of the conflicting experimental results which may aid detailed understanding of the CSQ2 regulatory role. Although we mainly focus on the cardiac isoform of the proteins, some aspects of more extensive work carried out on the skeletal isoform are also discussed.
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Affiliation(s)
- Marta Gaburjakova
- Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Vlarska 5, Bratislava, Slovak Republic.
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Napolitano C, Bloise R, Memmi M, Priori SG. Clinical utility gene card for: Catecholaminergic polymorphic ventricular tachycardia (CPVT). Eur J Hum Genet 2013; 22:ejhg201355. [PMID: 23549275 DOI: 10.1038/ejhg.2013.55] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Carlo Napolitano
- 1] IRCCS Fondazione Maugeri, Pavia, Italy [2] Cardiovascular Genetics, Leon Charney Division of Cardiology, New York University, New York, NY, USA
| | | | | | - Silvia Giuliana Priori
- 1] IRCCS Fondazione Maugeri, Pavia, Italy [2] Cardiovascular Genetics, Leon Charney Division of Cardiology, New York University, New York, NY, USA [3] Department of Molecular Medicine, University of Pavia, Pavia, Italy
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48
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Stanley WC, Keehan KH. Update on innovative initiatives for the American Journal of Physiology-Heart and Circulatory Physiology. Am J Physiol Heart Circ Physiol 2013; 304:H1045-9. [PMID: 23457015 DOI: 10.1152/ajpheart.00082.2013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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50
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Poláková E, Sobie EA. Alterations in T-tubule and dyad structure in heart disease: challenges and opportunities for computational analyses. Cardiovasc Res 2013; 98:233-9. [PMID: 23396602 DOI: 10.1093/cvr/cvt026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Compelling recent experimental results make clear that sub-cellular structures are altered in ventricular myocytes during the development of heart failure, in both human samples and diverse experimental models. These alterations can include, but are not limited to, changes in the clusters of sarcoplasmic reticulum (SR) Ca(2+)-release channels, ryanodine receptors, and changes in the average distance between the cell membrane and ryanodine receptor clusters. In this review, we discuss the potential consequences of these structural alterations on the triggering of SR Ca(2+) release during excitation-contraction coupling. In particular, we describe how mathematical models of local SR Ca(2+) release can be used to predict functional changes resulting from diverse modifications that occur in disease states. We review recent studies that have used simulations to understand the consequences of sub-cellular structural changes, and we discuss modifications that will allow for future modelling studies to address unresolved questions. We conclude with a discussion of improvements in both experimental and mathematical modelling techniques that will be required to provide a stronger quantitative understanding of the functional consequences of changes in sub-cellular structure in heart disease.
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Affiliation(s)
- Eva Poláková
- Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, One Gustave Levy Place, Box 1215, New York, NY 10029, USA
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