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Song T, Hui W, Huang M, Guo Y, Yu M, Yang X, Liu Y, Chen X. Dynamic Changes in Ion Channels during Myocardial Infarction and Therapeutic Challenges. Int J Mol Sci 2024; 25:6467. [PMID: 38928173 PMCID: PMC11203447 DOI: 10.3390/ijms25126467] [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: 04/20/2024] [Revised: 06/02/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024] Open
Abstract
In different areas of the heart, action potential waveforms differ due to differences in the expressions of sodium, calcium, and potassium channels. One of the characteristics of myocardial infarction (MI) is an imbalance in oxygen supply and demand, leading to ion imbalance. After MI, the regulation and expression levels of K+, Ca2+, and Na+ ion channels in cardiomyocytes are altered, which affects the regularity of cardiac rhythm and leads to myocardial injury. Myocardial fibroblasts are the main effector cells in the process of MI repair. The ion channels of myocardial fibroblasts play an important role in the process of MI. At the same time, a large number of ion channels are expressed in immune cells, which play an important role by regulating the in- and outflow of ions to complete intracellular signal transduction. Ion channels are widely distributed in a variety of cells and are attractive targets for drug development. This article reviews the changes in different ion channels after MI and the therapeutic drugs for these channels. We analyze the complex molecular mechanisms behind myocardial ion channel regulation and the challenges in ion channel drug therapy.
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Affiliation(s)
- Tongtong Song
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
- Department of Anatomy, College of Basic Medical Sciences, Jilin University, Changchun 130012, China
| | - Wenting Hui
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
| | - Min Huang
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
| | - Yan Guo
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
| | - Meiyi Yu
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
| | - Xiaoyu Yang
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
| | - Yanqing Liu
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
| | - Xia Chen
- Department of Pharmacology, College of Basic Medical Sciences, Jilin University, Changchun 130012, China; (T.S.); (W.H.); (M.H.); (Y.G.); (M.Y.); (X.Y.); (Y.L.)
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Mitronova GY, Quentin C, Belov VN, Wegener JW, Kiszka KA, Lehnart SE. 1,4-Benzothiazepines with Cyclopropanol Groups and Their Structural Analogues Exhibit Both RyR2-Stabilizing and SERCA2a-Stimulating Activities. J Med Chem 2023; 66:15761-15775. [PMID: 37991191 PMCID: PMC10726367 DOI: 10.1021/acs.jmedchem.3c01235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 10/24/2023] [Accepted: 11/07/2023] [Indexed: 11/23/2023]
Abstract
To discover new multifunctional agents for the treatment of cardiovascular diseases, we designed and synthesized a series of compounds with a cyclopropyl alcohol moiety and evaluated them in biochemical assays. Biological screening identified derivatives with dual activity: preventing Ca2+ leak through ryanodine receptor 2 (RyR2) and enhancing cardiac sarco-endoplasmic reticulum (SR) Ca2+ load by activation of Ca2+-dependent ATPase 2a (SERCA2a). The compounds that stabilize RyR2 at micro- and nanomolar concentrations are either structurally related to RyR-stabilizing drugs or Rycals or have structures similar to them. The novel compounds also demonstrate a good ability to increase ATP hydrolysis mediated by SERCA2a activity in cardiac microsomes, e.g., the half-maximal effective concentration (EC50) was as low as 383 nM for compound 12a, which is 1,4-benzothiazepine with two cyclopropanol groups. Our findings indicate that these derivatives can be considered as new lead compounds to improve cardiac function in heart failure.
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Affiliation(s)
- Gyuzel Y. Mitronova
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
- German
Centre for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen 37075, Germany
| | - Christine Quentin
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Vladimir N. Belov
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Jörg W. Wegener
- Department
of Cardiology & Pulmonology, Heart Research Center Göttingen, University Medical Center Göttingen, Robert-Koch-Strasse 42a, Göttingen 37075, Germany
- German
Centre for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen 37075, Germany
| | - Kamila A. Kiszka
- Department
of NanoBiophotonics, Max Planck Institute
for Multidisciplinary Sciences, Am Fassberg 11, Göttingen 37077, Germany
| | - Stephan E. Lehnart
- Department
of Cardiology & Pulmonology, Heart Research Center Göttingen, University Medical Center Göttingen, Robert-Koch-Strasse 42a, Göttingen 37075, Germany
- German
Centre for Cardiovascular Research (DZHK), Partner Site Göttingen, Göttingen 37075, Germany
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3
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Abstract
Calcium ions (Ca2+) are the basis of a unique and potent array of cellular responses. Calmodulin (CaM) is a small but vital protein that is able to rapidly transmit information about changes in Ca2+ concentrations to its regulatory targets. CaM plays a critical role in cellular Ca2+ signaling, and interacts with a myriad of target proteins. Ca2+-dependent modulation by CaM is a major component of a diverse array of processes, ranging from gene expression in neurons to the shaping of the cardiac action potential in heart cells. Furthermore, the protein sequence of CaM is highly evolutionarily conserved, and identical CaM proteins are encoded by three independent genes (CALM1-3) in humans. Mutations within any of these three genes may lead to severe cardiac deficits including severe long QT syndrome (LQTS) and/or catecholaminergic polymorphic ventricular tachycardia (CPVT). Research into disease-associated CaM variants has identified several proteins modulated by CaM that are likely to underlie the pathogenesis of these calmodulinopathies, including the cardiac L-type Ca2+ channel (LTCC) CaV1.2, and the sarcoplasmic reticulum Ca2+ release channel, ryanodine receptor 2 (RyR2). Here, we review the research that has been done to identify calmodulinopathic CaM mutations and evaluate the mechanisms underlying their role in disease.
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Affiliation(s)
- John W. Hussey
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Worawan B. Limpitikul
- Department of Medicine, Division of Cardiology, Massachusetts General Hospital, Boston, MA, USA
| | - Ivy E. Dick
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
- CONTACT Ivy E. Dick School of Medicine, University of Maryland, Baltimore, MD21210
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Wang YX, Reyes-García J, Di Mise A, Zheng YM. Role of ryanodine receptor 2 and FK506-binding protein 12.6 dissociation in pulmonary hypertension. J Gen Physiol 2023; 155:213798. [PMID: 36625865 PMCID: PMC9836826 DOI: 10.1085/jgp.202213100] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 07/29/2022] [Accepted: 12/19/2022] [Indexed: 01/11/2023] Open
Abstract
Pulmonary hypertension (PH) is a devastating disease characterized by a progressive increase in pulmonary arterial pressure leading to right ventricular failure and death. A major cellular response in this disease is the contraction of smooth muscle cells (SMCs) of the pulmonary vasculature. Cell contraction is determined by the increase in intracellular Ca2+ concentration ([Ca2+]i), which is generated and regulated by various ion channels. Several studies by us and others have shown that ryanodine receptor 2 (RyR2), a Ca2+-releasing channel in the sarcoplasmic reticulum (SR), is an essential ion channel for the control of [Ca2+]i in pulmonary artery SMCs (PASMCs), thereby mediating the sustained vasoconstriction seen in PH. FK506-binding protein 12.6 (FKBP12.6) strongly associates with RyR2 to stabilize its functional activity. FKBP12.6 can be dissociated from RyR2 by a hypoxic stimulus to increase channel function and Ca2+ release, leading to pulmonary vasoconstriction and PH. More specifically, dissociation of the RyR2-FKBP12.6 complex is a consequence of increased mitochondrial ROS generation mediated by the Rieske iron-sulfur protein (RISP) at the mitochondrial complex III after hypoxia. Overall, RyR2/FKBP12.6 dissociation and the corresponding signaling pathway may be an important factor in the development of PH. Novel drugs and biologics targeting RyR2, FKBP12.6, and related molecules may become unique effective therapeutics for PH.
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Affiliation(s)
- Yong-Xiao Wang
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA,Correspondence to Yong-Xiao Wang:
| | - Jorge Reyes-García
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA,Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México,Ciudad de México, México
| | - Annarita Di Mise
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA,Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Yun-Min Zheng
- Department of Molecular and Cellular Physiology, Albany Medical College, Albany, NY, USA,Yun-Min Zheng:
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Hadiatullah H, He Z, Yuchi Z. Structural Insight Into Ryanodine Receptor Channelopathies. Front Pharmacol 2022; 13:897494. [PMID: 35677449 PMCID: PMC9168041 DOI: 10.3389/fphar.2022.897494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/09/2022] [Indexed: 11/28/2022] Open
Abstract
The ryanodine receptors (RyRs) are large cation-selective ligand-gated channels that are expressed in the sarcoplasmic reticulum (SR) membrane. They mediate the controlled release of Ca2+ from SR and play an important role in many cellular processes. The mutations in RyRs are associated with several skeletal muscle and cardiac conditions, including malignant hyperthermia (MH), central core disease (CCD), catecholaminergic polymorphic ventricular tachycardia (CPVT), and arrhythmogenic right ventricular dysplasia (ARVD). Recent breakthroughs in structural biology including cryo-electron microscopy (EM) and X-ray crystallography allowed the determination of a number of near-atomic structures of RyRs, including wildtype and mutant structures as well as the structures in complex with different modulating molecules. This allows us to comprehend the physiological gating and regulatory mechanisms of RyRs and the underlying pathological mechanisms of the disease-causing mutations. In this review, based on the insights gained from the available high-resolution structures of RyRs, we address several questions: 1) what are the gating mechanisms of different RyR isoforms; 2) how RyRs are regulated by multiple channel modulators, including ions, small molecules, and regulatory proteins; 3) how do disease-causing mutations affect the structure and function of RyRs; 4) how can these structural information aid in the diagnosis of the related diseases and the development of pharmacological therapies.
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Affiliation(s)
- Hadiatullah Hadiatullah
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, Collaborative Innovation Center of Chemical Science and Engineering, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
- Department of Molecular Pharmacology, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin’s Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Zhao He
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, Collaborative Innovation Center of Chemical Science and Engineering, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
- Department of Molecular Pharmacology, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin’s Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Zhiguang Yuchi
- Tianjin Key Laboratory for Modern Drug Delivery and High-Efficiency, Collaborative Innovation Center of Chemical Science and Engineering, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin, China
- Department of Molecular Pharmacology, National Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin’s Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
- *Correspondence: Zhiguang Yuchi,
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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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7
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Aizpurua JM, Miranda JI, Irastorza A, Torres E, Eceiza M, Sagartzazu-Aizpurua M, Ferrón P, Aldanondo G, Lasa-Fernández H, Marco-Moreno P, Dadie N, López de Munain A, Vallejo-Illarramendi A. Discovery of a novel family of FKBP12 "reshapers" and their use as calcium modulators in skeletal muscle under nitro-oxidative stress. Eur J Med Chem 2021; 213:113160. [PMID: 33493827 DOI: 10.1016/j.ejmech.2021.113160] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/23/2020] [Accepted: 01/04/2021] [Indexed: 10/22/2022]
Abstract
The hypothesis of rescuing FKBP12/RyR1 interaction and intracellular calcium homeostasis through molecular "reshaping" of FKBP12 was investigated. To this end, novel 4-arylthioalkyl-1-carboxyalkyl-1,2,3-triazoles were designed and synthesized, and their efficacy was tested in human myotubes. A library of 17 compounds (10a-n) designed to dock the FKBP12/RyR1 hot-spot interface contact residues, was readily prepared from free α-amino acids and arylthioalkynes using CuAAC "click" protocols amenable to one-pot transformations in high overall yields and total configurational integrity. To model nitro-oxidative stress, human myotubes were treated with the peroxynitrite donor SIN1, and evidence was found that some triazoles 10 were able to normalize calcium levels, as well as FKBP12/RyR1 interaction. For example, compound 10 b at 150 nM rescued 46% of FKBP12/RyR1 interaction and up to 70% of resting cytosolic calcium levels in human myotubes under nitro-oxidative stress. All compounds 10 analyzed showed target engagement to FKBP12 and low levels of cytotoxicity in vitro. Compounds 10b, 10c, 10h, and 10iR were identified as potential therapeutic candidates to protect myotubes in muscle disorders with underlying nitro-oxidative stress, FKBP12/RyR1 dysfunction and calcium dysregulation.
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Affiliation(s)
- Jesus M Aizpurua
- Joxe Mari Korta R&D Center, Departamento de Química Orgánica-I, Universidad Del País Vasco UPV/EHU, Avda. Tolosa-72, 20018, San Sebastián, Spain.
| | - José I Miranda
- Joxe Mari Korta R&D Center, Departamento de Química Orgánica-I, Universidad Del País Vasco UPV/EHU, Avda. Tolosa-72, 20018, San Sebastián, Spain
| | - Aitziber Irastorza
- Joxe Mari Korta R&D Center, Departamento de Química Orgánica-I, Universidad Del País Vasco UPV/EHU, Avda. Tolosa-72, 20018, San Sebastián, Spain
| | - Endika Torres
- Joxe Mari Korta R&D Center, Departamento de Química Orgánica-I, Universidad Del País Vasco UPV/EHU, Avda. Tolosa-72, 20018, San Sebastián, Spain
| | - Maite Eceiza
- Joxe Mari Korta R&D Center, Departamento de Química Orgánica-I, Universidad Del País Vasco UPV/EHU, Avda. Tolosa-72, 20018, San Sebastián, Spain
| | - Maialen Sagartzazu-Aizpurua
- Joxe Mari Korta R&D Center, Departamento de Química Orgánica-I, Universidad Del País Vasco UPV/EHU, Avda. Tolosa-72, 20018, San Sebastián, Spain
| | - Pablo Ferrón
- Miramoon Pharma S.L., Avda Tolosa-72, 20018, San Sebastián, Spain
| | - Garazi Aldanondo
- Instituto de Investigación Sanitaria Biodonostia, Grupo de Enfermedades Neuromusculares, Paseo Dr Begiristain s/n, 20014, San Sebastián, Spain; CIBERNED, Instituto de Salud Carlos III, 28031, Madrid, Spain
| | - Haizpea Lasa-Fernández
- Instituto de Investigación Sanitaria Biodonostia, Grupo de Enfermedades Neuromusculares, Paseo Dr Begiristain s/n, 20014, San Sebastián, Spain; CIBERNED, Instituto de Salud Carlos III, 28031, Madrid, Spain; Grupo de Neurosciencias, Departamentos de Pediatría y Neurociencias, Universidad Del País Vasco UPV/EHU, Hospital Donostia, Paseo Dr Begiristain S/n, 20014, San Sebastián, Spain
| | - Pablo Marco-Moreno
- Instituto de Investigación Sanitaria Biodonostia, Grupo de Enfermedades Neuromusculares, Paseo Dr Begiristain s/n, 20014, San Sebastián, Spain; CIBERNED, Instituto de Salud Carlos III, 28031, Madrid, Spain
| | - Naroa Dadie
- Grupo de Neurosciencias, Departamentos de Pediatría y Neurociencias, Universidad Del País Vasco UPV/EHU, Hospital Donostia, Paseo Dr Begiristain S/n, 20014, San Sebastián, Spain
| | - Adolfo López de Munain
- Instituto de Investigación Sanitaria Biodonostia, Grupo de Enfermedades Neuromusculares, Paseo Dr Begiristain s/n, 20014, San Sebastián, Spain; CIBERNED, Instituto de Salud Carlos III, 28031, Madrid, Spain; Grupo de Neurosciencias, Departamentos de Pediatría y Neurociencias, Universidad Del País Vasco UPV/EHU, Hospital Donostia, Paseo Dr Begiristain S/n, 20014, San Sebastián, Spain
| | - Ainara Vallejo-Illarramendi
- Instituto de Investigación Sanitaria Biodonostia, Grupo de Enfermedades Neuromusculares, Paseo Dr Begiristain s/n, 20014, San Sebastián, Spain; CIBERNED, Instituto de Salud Carlos III, 28031, Madrid, Spain; Grupo de Neurosciencias, Departamentos de Pediatría y Neurociencias, Universidad Del País Vasco UPV/EHU, Hospital Donostia, Paseo Dr Begiristain S/n, 20014, San Sebastián, Spain.
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8
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Mechanisms underlying pathological Ca 2+ handling in diseases of the heart. Pflugers Arch 2021; 473:331-347. [PMID: 33399957 PMCID: PMC10070045 DOI: 10.1007/s00424-020-02504-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/01/2020] [Accepted: 12/09/2020] [Indexed: 02/07/2023]
Abstract
Cardiomyocyte contraction relies on precisely regulated intracellular Ca2+ signaling through various Ca2+ channels and transporters. In this article, we will review the physiological regulation of Ca2+ handling and its role in maintaining normal cardiac rhythm and contractility. We discuss how inherited variants or acquired defects in Ca2+ channel subunits contribute to the development or progression of diseases of the heart. Moreover, we highlight recent insights into the role of protein phosphatase subunits and striated muscle preferentially expressed protein kinase (SPEG) in atrial fibrillation, heart failure, and cardiomyopathies. Finally, this review summarizes current drug therapies and new advances in genome editing as therapeutic strategies for the cardiac diseases caused by aberrant intracellular Ca2+ signaling.
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9
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Njegic A, Wilson C, Cartwright EJ. Targeting Ca 2 + Handling Proteins for the Treatment of Heart Failure and Arrhythmias. Front Physiol 2020; 11:1068. [PMID: 33013458 PMCID: PMC7498719 DOI: 10.3389/fphys.2020.01068] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/04/2020] [Indexed: 12/18/2022] Open
Abstract
Diseases of the heart, such as heart failure and cardiac arrhythmias, are a growing socio-economic burden. Calcium (Ca2+) dysregulation is key hallmark of the failing myocardium and has long been touted as a potential therapeutic target in the treatment of a variety of cardiovascular diseases (CVD). In the heart, Ca2+ is essential for maintaining normal cardiac function through the generation of the cardiac action potential and its involvement in excitation contraction coupling. As such, the proteins which regulate Ca2+ cycling and signaling play a vital role in maintaining Ca2+ homeostasis. Changes to the expression levels and function of Ca2+-channels, pumps and associated intracellular handling proteins contribute to altered Ca2+ homeostasis in CVD. The remodeling of Ca2+-handling proteins therefore results in impaired Ca2+ cycling, Ca2+ leak from the sarcoplasmic reticulum and reduced Ca2+ clearance, all of which contributes to increased intracellular Ca2+. Currently, approved treatments for targeting Ca2+ handling dysfunction in CVD are focused on Ca2+ channel blockers. However, whilst Ca2+ channel blockers have been successful in the treatment of some arrhythmic disorders, they are not universally prescribed to heart failure patients owing to their ability to depress cardiac function. Despite the progress in CVD treatments, there remains a clear need for novel therapeutic approaches which are able to reverse pathophysiology associated with heart failure and arrhythmias. Given that heart failure and cardiac arrhythmias are closely associated with altered Ca2+ homeostasis, this review will address the molecular changes to proteins associated with both Ca2+-handling and -signaling; their potential as novel therapeutic targets will be discussed in the context of pre-clinical and, where available, clinical data.
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Affiliation(s)
- Alexandra Njegic
- Division of Cardiovascular Sciences, The University of Manchester, Manchester, United Kingdom.,Centre for Tumour Biology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Claire Wilson
- Division of Cardiovascular Sciences, The University of Manchester, Manchester, United Kingdom.,Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom
| | - Elizabeth J Cartwright
- Division of Cardiovascular Sciences, The University of Manchester, Manchester, United Kingdom
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10
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Yoshizawa K, Nakashima K, Tabuchi M, Okumura A, Nakatake Y, Yamada M, Tsuneoka Y, Higashi T. Benzothiazepines, diltiazem and JTV-519, exert an anxiolytic-like effect via neurosteroid biosynthesis in mice. J Pharmacol Sci 2020; 143:234-237. [PMID: 32249061 DOI: 10.1016/j.jphs.2020.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/07/2020] [Accepted: 03/11/2020] [Indexed: 10/24/2022] Open
Abstract
We investigated whether benzothiazepines could produce anxiolytic effects via allopregnanolone (ALLO) biosynthesis in mice. We compared the behavioral effects caused by benzothiazepines to those caused by carbamazepine and sodium valproate. We found that a pretreatment with finasteride (a 5 alpha-reductase inhibitor) suppressed carbamazepine-induced anxiolytic effects but not the effects of sodium valproate. Similar to carbamazepine, diltiazem and JTV-519 displayed anxiolytic effects that were suppressed by a pretreatment with finasteride. We clearly demonstrate that the benzothiazepines, diltiazem and JTV-519, exert an anxiolytic-like effect via ALLO biosynthesis in mice.
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Affiliation(s)
- Kazumi Yoshizawa
- Laboratory of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Japan.
| | - Kozue Nakashima
- Laboratory of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Japan
| | - Mizuho Tabuchi
- Laboratory of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Japan
| | - Ayano Okumura
- Laboratory of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Japan
| | - Yuko Nakatake
- Laboratory of Pharmacology and Therapeutics, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Japan; Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Japan
| | - Mitsuhiko Yamada
- Department of Neuropsychopharmacology, National Institute of Mental Health, National Center of Neurology and Psychiatry, Japan
| | - Yayoi Tsuneoka
- Department of Environmental Health, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, Japan
| | - Tatsuya Higashi
- Laboratory of Analytical and Bioanalytical Science, Faculty of Pharmaceutical Sciences, Tokyo University of Science, Japan
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Nassal D, Gratz D, Hund TJ. Challenges and Opportunities for Therapeutic Targeting of Calmodulin Kinase II in Heart. Front Pharmacol 2020; 11:35. [PMID: 32116711 PMCID: PMC7012788 DOI: 10.3389/fphar.2020.00035] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 01/14/2020] [Indexed: 12/19/2022] Open
Abstract
Heart failure remains a major health burden around the world. Despite great progress in delineation of molecular mechanisms underlying development of disease, standard therapy has not advanced at the same pace. The multifunctional signaling molecule Ca2+/calmodulin-dependent protein kinase II (CaMKII) has received considerable attention over recent years for its central role in maladaptive remodeling and arrhythmias in the setting of chronic disease. However, these basic science discoveries have yet to translate into new therapies for human patients. This review addresses both the promise and barriers to developing translational therapies that target CaMKII signaling to abrogate pathologic remodeling in the setting of chronic disease. Efforts in small molecule design are discussed, as well as alternative targeting approaches that exploit novel avenues for compound delivery and/or genetic approaches to affect cardiac CaMKII signaling. These alternative strategies provide hope for overcoming some of the challenges that have limited the development of new therapies.
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Affiliation(s)
- Drew Nassal
- The Frick Center for Heart Failure and Arrhythmia and Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States
| | - Daniel Gratz
- The Frick Center for Heart Failure and Arrhythmia and Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States.,Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States
| | - Thomas J Hund
- The Frick Center for Heart Failure and Arrhythmia and Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, OH, United States.,Department of Biomedical Engineering, College of Engineering, The Ohio State University, Columbus, OH, United States.,Department of Internal Medicine, The Ohio State University Wexner Medical Center, Columbus, OH, United States
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12
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Ngoc Toan D, Thanh ND, Truong MX, Nghia Bang D, Thanh Nga M, Thi Thu Huong N. Synthesis, cytotoxic activity, ADMET and molecular docking study of quinoline-based hybrid compounds of 1,5-benzothiazepines. NEW J CHEM 2020. [DOI: 10.1039/d0nj04295a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Some α,β-unsaturated ketones 4a–g of 3-acetyl-4-hydroxyquinolin-2(1H)-one were prepared and converted into a series of new hybrid compounds, quinoline-benzothiazepine 6a–g. Compounds 6d and 6g had the best activity against HepG2 and KB cell lines.
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Affiliation(s)
- Duong Ngoc Toan
- Faculty of Chemistry
- TNU University of Education (Thai Nguyen University)
- Vietnam
- Faculty of Chemistry
- VNU University of Science (Vietnam National University, Ha Noi)
| | - Nguyen Dinh Thanh
- Faculty of Chemistry
- VNU University of Science (Vietnam National University, Ha Noi)
- Ha Noi
- Vietnam
| | - Mai Xuan Truong
- Faculty of Chemistry
- TNU University of Education (Thai Nguyen University)
- Vietnam
| | - Duong Nghia Bang
- Faculty of Chemistry
- TNU University of Science (Thai Nguyen University)
- Tan Thinh Ward
- Thai Nguyen City
- Vietnam
| | - Mai Thanh Nga
- Faculty of Chemistry
- TNU University of Education (Thai Nguyen University)
- Vietnam
| | - Nguyen Thi Thu Huong
- Faculty of Chemistry
- VNU University of Science (Vietnam National University, Ha Noi)
- Ha Noi
- Vietnam
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Kageyama M, Toyoda S, Sakuma M, Inami S, Nasuno T, Haruyama A, Kikuchi M, Abe S, Inoue T. Theophylline-Induced Left Ventricular Relaxation Disturbance in Magnesium-Deficient Rats: Improvement by K201, a Novel 1,4-Benzothiazepine Derivative. ACTA CARDIOLOGICA SINICA 2018; 34:432-439. [PMID: 30271094 PMCID: PMC6160519 DOI: 10.6515/acs.201809_34(5).20180513a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
BACKGROUND Although magnesium deficiency induces left ventricular dysfunction, it is not known whether both systolic and diastolic functions are altered to the same extent. In this study, we investigated the effects of theophylline on left ventricular function in rats fed a normal diet or a magnesium-deficient diet for 1 month, and determined whether K201, a multi-channel blocker, modulated the effects of theophylline. METHODS Theophylline was infused at 5 mg/kg/min for 15 min in 6 control rats and 6 magnesium-deficient rats, and hemodynamic measurements were performed. In another 6 magnesium-deficient rats, K201 was infused at 0.1 mg/kg/min for 15 min simultaneously with theophylline. RESULTS Theophylline induced persistent increases in heart rate, peak positive first derivative of left ventricular pressure (+dP/dt), and a transient increase in left ventricular end-diastolic pressure (LVEDP), but did not affect left ventricular systolic pressure (LVSP) and peak negative first derivative of left ventricular pressure (-dP/dt) in the control rats. In contrast, in the magnesium-deficient rats, there was a persistent decrease in LVSP and a persistent increase in -dP/dt after theophylline infusion, although increases in heart rate, +dP/dt and LVEDP were similar to those in the control rats. When K201 was infused along with theophylline in the magnesium-deficient rats, both the decrease in LVSP and increase in -dP/dt were suppressed. CONCLUSIONS Theophylline impaired left ventricular function in the magnesium-deficient rats, and this was improved by K201. K201 may provide new insights regarding future strategies for heart failure treatment.
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Affiliation(s)
- Michiya Kageyama
- Department of Cardiovascular Medicine, Nasu Red Cross Hospital, Otawara;
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Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Shigeru Toyoda
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Masashi Sakuma
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Shu Inami
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Takahisa Nasuno
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Akiko Haruyama
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Migaku Kikuchi
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Shichiro Abe
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
| | - Teruo Inoue
- Department of Cardiovascular Medicine, Dokkyo Medical University, School of Medicine, Mibu, Tochigi, Japan
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14
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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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del Canto I, Such-Miquel L, Brines L, Soler C, Zarzoso M, Calvo C, Parra G, Tormos Á, Alberola A, Millet J, Such L, Chorro FJ. Effects of JTV-519 on stretch-induced manifestations of mechanoelectric feedback. Clin Exp Pharmacol Physiol 2016; 43:1062-1070. [DOI: 10.1111/1440-1681.12630] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 07/16/2016] [Accepted: 08/01/2016] [Indexed: 12/29/2022]
Affiliation(s)
- Irene del Canto
- Department of Medicine; Valencia University “Estudi General”; Valencia Spain
| | - Luis Such-Miquel
- Department of Physiotherapy; Valencia University “Estudi General”; Valencia Spain
| | - Laia Brines
- Department of Physiology; Valencia University “Estudi General”; Valencia Spain
| | - Carlos Soler
- Department of Physiology; Valencia University “Estudi General”; Valencia Spain
| | - Manuel Zarzoso
- Department of Physiotherapy; Valencia University “Estudi General”; Valencia Spain
| | - Conrado Calvo
- Department of Electronic Engineering; Valencia Polytechnic University; Valencia Spain
| | - Germán Parra
- Department of Physiology; Valencia University “Estudi General”; Valencia Spain
| | - Álvaro Tormos
- Department of Electronic Engineering; Valencia Polytechnic University; Valencia Spain
| | - Antonio Alberola
- Department of Physiology; Valencia University “Estudi General”; Valencia Spain
| | - José Millet
- Department of Electronic Engineering; Valencia Polytechnic University; Valencia Spain
| | - Luis Such
- Department of Physiology; Valencia University “Estudi General”; Valencia Spain
| | - Francisco J. Chorro
- Department of Medicine; Valencia University “Estudi General”; Valencia Spain
- Department of Cardiology; Valencia University Clinic Hospital; INCLIVA; Valencia Spain
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Darcy YL, Diaz-Sylvester PL, Copello JA. K201 (JTV519) is a Ca2+-Dependent Blocker of SERCA and a Partial Agonist of Ryanodine Receptors in Striated Muscle. Mol Pharmacol 2016; 90:106-15. [PMID: 27235390 DOI: 10.1124/mol.115.102277] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 05/26/2016] [Indexed: 12/26/2022] Open
Abstract
K201 (JTV-519) may prevent abnormal Ca(2+) leak from the sarcoplasmic reticulum (SR) in the ischemic heart and skeletal muscle (SkM) by stabilizing the ryanodine receptors (RyRs; RyR1 and RyR2, respectively). We tested direct modulation of the SR Ca(2+)-stimulated ATPase (SERCA) and RyRs by K201. In isolated cardiac and SkM SR microsomes, K201 slowed the rate of SR Ca(2+) loading, suggesting potential SERCA block and/or RyR agonism. K201 displayed Ca(2+)-dependent inhibition of SERCA-dependent ATPase activity, which was measured in microsomes incubated with 200, 2, and 0.25 µM Ca(2+) and with the half-maximal K201 inhibitory doses (IC50) estimated at 130, 19, and 9 µM (cardiac muscle) and 104, 13, and 5 µM (SkM SR). K201 (≥5 µM) increased RyR1-mediated Ca(2+) release from SkM microsomes. Maximal K201 doses at 80 µM produced ∼37% of the increase in SkM SR Ca(2+) release observed with the RyR agonist caffeine. K201 (≥5 µM) increased the open probability (Po) of very active ("high-activity") RyR1 of SkM reconstituted into bilayers, but it had no effect on "low-activity" channels. Likewise, K201 activated cardiac RyR2 under systolic Ca(2+) conditions (∼5 µM; channels at Po ∼0.3) but not under diastolic Ca(2+) conditions (∼100 nM; Po < 0.01). Thus, K201-induced the inhibition of SR Ca(2+) leak found in cell-system studies may relate to potentially potent SERCA block under resting Ca(2+) conditions. SERCA block likely produces mild SR depletion in normal conditions but could prevent SR Ca(2+) overload under pathologic conditions, thus precluding abnormal RyR-mediated Ca(2+) release.
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Affiliation(s)
- Yuanzhao L Darcy
- Department of Pharmacology (Y.L.D., P.L.D.-S., J.A.C.) and Center for Clinical Research (P.L.D.-S.), Southern Illinois University School of Medicine, Springfield, Illinois
| | - Paula L Diaz-Sylvester
- Department of Pharmacology (Y.L.D., P.L.D.-S., J.A.C.) and Center for Clinical Research (P.L.D.-S.), Southern Illinois University School of Medicine, Springfield, Illinois
| | - Julio A Copello
- Department of Pharmacology (Y.L.D., P.L.D.-S., J.A.C.) and Center for Clinical Research (P.L.D.-S.), Southern Illinois University School of Medicine, Springfield, Illinois
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17
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Akbarzadeh M, Bakavoli M, Eshghi H, Shiri A, Tajabadi J. Synthesis of Dihydrobenzo[b]pyrimido[4,5-e][1,4]Thiazepines; Derivatives of a Novel Ring System. JOURNAL OF CHEMICAL RESEARCH 2015. [DOI: 10.3184/174751915x14401726334645] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Several derivatives of the novel dihydrobenzo[b]pyrimido[4,5-e][1,4]thiazepine ring system have been synthesised through the initial heterocyclisation of 2,4-dichloro-5-(chloromethyl)-6-methylpyrimidine with o-aminothiophenol followed by treatment with various secondary amines in boiling ethanol.
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Affiliation(s)
- Marzieh Akbarzadeh
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Mehdi Bakavoli
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Hossein Eshghi
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Ali Shiri
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
| | - Javad Tajabadi
- Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran
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19
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Abstract
Atrial fibrillation (AF) is the most common cardiac arrhythmia, contributing to increased morbidity and reduced survival through its associations with stroke and heart failure. AF contributes to a four- to fivefold increase in the risk of stroke in the general population and is responsible for 10-15 % of all ischemic strokes. Diagnosis and treatment of AF require considerable health care resources. Current therapies to restore sinus rhythm in AF are suboptimal and are limited either by their pro-arrhythmic effects or by their procedure-related complications. These limitations have necessitated identification of newer therapeutic targets to expand the treatment options. There has been a considerable amount of research interest in investigating the mechanisms of initiation and propagation of AF. Despite extensive research focused on the pathogenesis of AF, a thorough understanding of various pathways mediating initiation and propagation of AF still remains limited. Research efforts focused on the identification of these pathways and molecular mediators have generated a great degree of interest for developing more targeted therapies. This review discusses the potential therapeutic targets and the results from experimental and clinical research investigating these targets.
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Konstantinou DM, Chatzizisis YS, Giannoglou GD. Pathophysiology-based novel pharmacotherapy for heart failure with preserved ejection fraction. Pharmacol Ther 2013; 140:156-66. [PMID: 23792088 DOI: 10.1016/j.pharmthera.2013.05.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 05/30/2013] [Indexed: 02/01/2023]
Abstract
Heart failure has become increasingly prevalent and poses a significant socioeconomic burden in the developed world. Approximately half of heart failure patients have preserved ejection fraction (HFpEF) and experience an increased morbidity and mortality attributed to the lack of effective therapies and to the presence of comorbidities. Suppression of neurohormonal activation by beta-blockers and renin-angiotensin-aldosterone system inhibitors is the cornerstone in the pharmacotherapy of heart failure with reduced ejection fraction (HFrEF). However, these medications are not associated with significant clinical benefit in HFpEF. In this review, we provide an in-depth pathophysiology-based update on novel pharmacotherapies of HFpEF. A deeper insight into the pathophysiologic mechanisms of HFpEF may create opportunities for novel pharmacological interventions.
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Affiliation(s)
- Dimitrios M Konstantinou
- First Department of Cardiology, AHEPA University Hospital, Aristotle University Medical School, Thessaloniki, Greece; Heart Failure Care Group, The Royal Brompton Hospital, London Imperial College, London, UK
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Cardiac ion channels and mechanisms for protection against atrial fibrillation. Rev Physiol Biochem Pharmacol 2013; 162:1-58. [PMID: 21987061 DOI: 10.1007/112_2011_3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Atrial fibrillation (AF) is recognised as the most common sustained cardiac arrhythmia in clinical practice. Ongoing drug development is aiming at obtaining atrial specific effects in order to prevent pro-arrhythmic, devastating ventricular effects. In principle, this is possible due to a different ion channel composition in the atria and ventricles. The present text will review the aetiology of arrhythmias with focus on AF and include a description of cardiac ion channels. Channels that constitute potentially atria-selective targets will be described in details. Specific focus is addressed to the recent discovery that Ca(2+)-activated small conductance K(+) channels (SK channels) are important for the repolarisation of atrial action potentials. Finally, an overview of current pharmacological treatment of AF is included.
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Sacherer M, Sedej S, Wakuła P, Wallner M, Vos MA, Kockskämper J, Stiegler P, Sereinigg M, von Lewinski D, Antoons G, Pieske BM, Heinzel FR. JTV519 (K201) reduces sarcoplasmic reticulum Ca²⁺ leak and improves diastolic function in vitro in murine and human non-failing myocardium. Br J Pharmacol 2013; 167:493-504. [PMID: 22509897 DOI: 10.1111/j.1476-5381.2012.01995.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Ca²⁺ leak from the sarcoplasmic reticulum (SR) via ryanodine receptors (RyR2s) contributes to cardiomyocyte dysfunction. RyR2 Ca²⁺ leak has been related to RyR2 phosphorylation. In these conditions, JTV519 (K201), a 1,4-benzothiazepine derivative and multi-channel blocker, stabilizes RyR2s and decrease SR Ca²⁺ leak. We investigated whether JTV519 stabilizes RyR2s without increasing RyR2 phosphorylation in mice and in non-failing human myocardium and explored underlying mechanisms. EXPERIMENTAL APPROACH SR Ca²⁺ leak was induced by ouabain in murine cardiomyocytes. [Ca²⁺]-transients, SR Ca²⁺ load and RyR2-mediated Ca²⁺ leak (sparks/waves) were quantified, with or without JTV519 (1 µmol·L⁻¹). Contribution of Ca²⁺ -/calmodulin-dependent kinase II (CaMKII) was assessed by KN-93 and Western blot (RyR2-Ser(2814) phosphorylation). Effects of JTV519 on contractile force were investigated in non-failing human ventricular trabeculae. KEY RESULTS Ouabain increased systolic and diastolic cytosolic [Ca²⁺](i) , SR [Ca²⁺], and SR Ca²⁺ leak (Ca²⁺ spark (SparkF) and Ca²⁺ wave frequency), independently of CaMKII and RyR-Ser(2814) phosphorylation. JTV519 decreased SparkF but also SR Ca²⁺ load. At matched SR [Ca²⁺], Ca²⁺ leak was significantly reduced by JTV519, but it had no effect on fractional Ca²⁺ release or Ca²⁺ wave propagation velocity. In human muscle, JTV519 was negatively inotropic at baseline but significantly enhanced ouabain-induced force and reduced its deleterious effects on diastolic function. CONCLUSIONS AND IMPLICATIONS JTV519 was effective in reducing SR Ca²⁺ leak by specifically regulating RyR2 opening at diastolic [Ca²⁺](i) in the absence of increased RyR2 phosphorylation at Ser(2814) , extending the potential use of JTV519 to conditions of acute cellular Ca²⁺ overload.
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Affiliation(s)
- M Sacherer
- Division of Cardiology, Medical University of Graz, Austria
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Otani N, Matsuda R, Oda K, Nishino S, Inoue T, Kaneko N. Protective effect of K201 on isoproterenol-induced and ischemic-reperfusion-induced ventricular arrhythmias in the rat: comparison with diltiazem. J Cardiovasc Pharmacol Ther 2012; 18:184-90. [PMID: 23144205 DOI: 10.1177/1074248412465489] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
AIM Ventricular arrhythmia (VA) is a risk for sudden death. Polymorphic ventricular tachycardia (VT) degenerating to ventricular fibrillation occurs subsequent to the prolongation of the QT interval following administration of catecholamines under Ca(2+) loading. Fatal VA also occurs in ischemia and ischemic-reperfusion. We compared the suppressive effect of K201 (JTV519), a multiple-channel blocker and cardiac ryanodine receptor-calcium release channel (RyR2) stabilizer, with that of diltiazem, a Ca(2+ )channel blocker, in 2 studies of isoproterenol-induced (n = 30) and ischemic-reperfusion-induced VAs (n = 38) in rats. METHODS Adult male Wistar rats were administered 12 mg/kg/min calcium chloride (CaCl(2)) for 20 minutes and then 6 μg/kg/min isoproterenol was infused with CaCl(2) for a further 20 minutes. In other rats, the left coronary artery was ligated for 5 minutes followed by reperfusion for 20 minutes. K201 or diltiazem (both 1 mg/kg) was administered before infusion of the isoproterenol or induction of ischemia. RESULTS After administration of isoproterenol under Ca(2+) loading, fatal VA frequently occurred in the vehicle (9 of 10 animals, 90%) and diltiazem (8 of 10, 80%) groups, and K201 significantly suppressed the incidences of arrhythmia and mortality (2 of 10, 20%). In the reperfusion study, the incidence and the time until occurrence of reperfusion-induced VA and mortality were significantly suppressed in the K201 (2 of 15 animals, 13%) and diltiazem (1 of 9 animals, 11%) groups compared to the vehicle group (8 of 14 animals, 57%). SIGNIFICANCE Induction of VA in an experimental model was achieved with a low dose of isoproterenol under Ca(2+) loading. K201 markedly suppressed both the isoproterenol-induced and the reperfusion-induced VAs, whereas diltiazem did not suppress the isoproterenol-induced VA. The results suggest that both VAs are related to early after depolarization (EAD) and indicate that K201 has the potential to suppress EAD by stabilizing RyR2 to mediate Ca(2+) release from the sarcoplasmic reticulum and acting as a multiple-channel blocker.
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Affiliation(s)
- Naoyuki Otani
- Department of Cardiovascular Medicine, Dokkyo Medical University, Kitakobayashi, Tochigi, Japan
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Mor S, Pahal P, Narasimhan B. Synthesis, characterization, biological evaluation and QSAR studies of 11-p-substituted phenyl-12-phenyl-11a,12-dihydro-11H-indeno[2,1-c][1,5]benzothiazepines as potential antimicrobial agents. Eur J Med Chem 2012; 57:196-210. [DOI: 10.1016/j.ejmech.2012.09.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Revised: 08/31/2012] [Accepted: 09/03/2012] [Indexed: 10/27/2022]
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Abstract
Metabolic syndrome is characterized by a combination of obesity, hypertension, insulin resistance, dyslipidemia, and impaired glucose tolerance. This multifaceted syndrome is often accompanied by a hyperdynamic circulatory state characterized by increased blood pressure, total blood volume, cardiac output, and metabolic tissue demand. Experimental, epidemiological, and clinical studies have demonstrated that patients with metabolic syndrome have significantly elevated cardiovascular morbidity and mortality rates. One of the main and frequent complications seen in metabolic syndrome is cardiovascular disease. The primary endpoints of cardiometabolic risk are coronary and peripheral arterial disease, myocardial infarction, congestive heart failure, arrhythmia, and stroke. Alterations in expression and/or functioning of several key proteins involved in regulating and maintaining ionic homeostasis can cause cardiac disturbances. One such group of proteins is known as ryanodine receptors (intracellular calcium release channels), which are the major channels through which Ca(2+) ions leave the sarcoplasmic reticulum, leading to cardiac muscle contraction. The economic cost of metabolic syndrome and its associated complications has a significant effect on health care budgets. Improvements in body weight, blood lipid profile, and hyperglycemia can reduce cardiometabolic risk. However, constant hyperadrenergic stimulation still contributes to the burden of disease. Normalization of the hyperdynamic circulatory state with conventional therapies is the most reasonable therapeutic strategy to date. JTV519 (K201) is a newly developed 1,4-benzothiazepine drug with antiarrhythmic and cardioprotective properties. It appears to be very effective in not only preventing but also in reversing the characteristic myocardial changes and preventing lethal arrhythmias. It is also a unique candidate to improve diastolic heart failure in metabolic syndrome.
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Affiliation(s)
- U Deniz Dincer
- Department of Pharmacology, Ufuk University School of Medicine. Mevlana Bulvari, Balgat, Ankara, Turkey
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Thomas NL, Williams AJ. Pharmacology of ryanodine receptors and Ca2+-induced Ca2+ release. ACTA ACUST UNITED AC 2012. [DOI: 10.1002/wmts.34] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Pasquié JL, Thireau J, Davy JM, Le Guennec JY, Richard S. Médicaments anti-arythmiques : Présent et futur. ARCHIVES OF CARDIOVASCULAR DISEASES SUPPLEMENTS 2011. [DOI: 10.1016/s1878-6480(11)70394-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Stams TRG, Oros A, der Nagel RV, Beekman JDM, Chamberlin P, Dittrich HC, Vos MA. Effects of K201 on repolarization and arrhythmogenesis in anesthetized chronic atrioventricular block dogs susceptible to dofetilide-induced torsade de pointes. Eur J Pharmacol 2011; 672:126-34. [PMID: 22001562 DOI: 10.1016/j.ejphar.2011.09.180] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 09/21/2011] [Accepted: 09/24/2011] [Indexed: 11/16/2022]
Abstract
The novel antiarrhythmic drug K201 (4-[3-{1-(4-benzyl)piperidinyl}propionyl]-7-methoxy-2,3,4,5-tetrahydro-1,4-benzothiazepine monohydrochloride) is currently in development for treatment of atrial fibrillation. K201 not only controls intracellular calcium release by the ryanodine receptors, but also possesses a ventricular action that might predispose to torsade de pointes arrhythmias. The anti- and proarrhythmic effects of K201 were investigated in the anesthetized canine chronic atrioventricular block model. Two doses of K201 (0.1 and 0.3mg/kg/2 min followed by 0.01 and 0.03 mg/kg/30 min i.v.) were tested in 4 serial experiments in dogs with normally conducted sinus rhythm (n=10) and in torsade de pointes-susceptible dogs with chronic atrioventricular block. Susceptibility was assessed with dofetilide (0.025 mg/kg/5 min i.v.). Beat-to-beat variability of repolarization was quantified as short-term variability of left ventricular monophasic action potential duration. In dogs with normally conducted sinus rhythm, both doses of K201 prolonged ventricular repolarization whereas only the higher dose prolonged atrial repolarization. At chronic atrioventricular block, dofetilide induced torsade de pointes in 9 of 10 dogs. K201 did neither suppress nor prevent dofetilide-induced torsade de pointes. K201 dose-dependently prolonged ventricular repolarization. In contrary to the lower dose, the higher dose did increase beat-to-beat variability of repolarization (from 1.2 ± 0.3 to 2.9 ± 0.8 ms, P<0.05) and resulted in spontaneous, repetitive torsade de pointes arrhythmias in 1 of 7 dogs; Programmed electrical stimulation resulted in torsade de pointes in 2 more dogs. In conclusion, both doses of K201 showed a class III effect. No relevant antiarrhythmic effects against dofetilide-induced torsade de pointes were seen. Only at the higher dose a proarrhythmic signal was observed.
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Affiliation(s)
- Thom R G Stams
- Department of Medical Physiology, Division Heart and Lungs, University Medical Center Utrecht, Yalelaan 50, 3584 CM Utrecht, The Netherlands.
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Two candidates at the heart of dysfunction: The ryanodine receptor and calcium/calmodulin protein kinase II as potential targets for therapeutic intervention—An in vivo perspective. Pharmacol Ther 2011; 131:204-20. [DOI: 10.1016/j.pharmthera.2011.02.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Accepted: 02/17/2011] [Indexed: 11/19/2022]
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Small-molecule modulators of inward rectifier K+ channels: recent advances and future possibilities. Future Med Chem 2011; 2:757-74. [PMID: 20543968 DOI: 10.4155/fmc.10.179] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Inward rectifier potassium (Kir) channels have been postulated as therapeutic targets for several common disorders including hypertension, cardiac arrhythmias and pain. With few exceptions, however, the small-molecule pharmacology of this family is limited to nonselective cardiovascular and neurologic drugs with off-target activity toward inward rectifiers. Consequently, the actual therapeutic potential and 'drugability' of most Kir channels has not yet been determined experimentally. The purpose of this review is to provide a comprehensive summary of publicly disclosed Kir channel small-molecule modulators and highlight recent targeted drug-discovery efforts toward Kir1.1 and Kir2.1. The review concludes with a brief speculation on how the field of Kir channel pharmacology will develop over the coming years and a discussion of the increasingly important role academic laboratories will play in this progress.
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Thireau J, Pasquié JL, Martel E, Le Guennec JY, Richard S. New drugs vs. old concepts: a fresh look at antiarrhythmics. Pharmacol Ther 2011; 132:125-45. [PMID: 21420430 DOI: 10.1016/j.pharmthera.2011.03.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 03/01/2011] [Indexed: 01/10/2023]
Abstract
Common arrhythmias, particularly atrial fibrillation (AF) and ventricular tachycardia/fibrillation (VT/VF) are a major public health concern. Classic antiarrhythmic (AA) drugs for AF are of limited effectiveness, and pose the risk of life-threatening VT/VF. For VT/VF, implantable cardiac defibrillators appear to be the unique, yet unsatisfactory, solution. Very few AA drugs have been successful in the last few decades, due to safety concerns or limited benefits in comparison to existing therapy. The Vaughan-Williams classification (one drug for one molecular target) appears too restrictive in light of current knowledge of molecular and cellular mechanisms. New AA drugs such as atrial-specific and/or multichannel blockers, upstream therapy and anti-remodeling drugs, are emerging. We focus on the cellular mechanisms related to abnormal Na⁺ and Ca²⁺ handling in AF, heart failure, and inherited arrhythmias, and on novel strategies aimed at normalizing ionic homeostasis. Drugs that prevent excessive Na⁺ entry (ranolazine) and aberrant diastolic Ca²⁺ release via the ryanodine receptor RyR2 (rycals, dantrolene, and flecainide) exhibit very interesting antiarrhythmic properties. These drugs act by normalizing, rather than blocking, channel activity. Ranolazine preferentially blocks abnormal persistent (vs. normal peak) Na⁺ currents, with minimal effects on normal channel function (cell excitability, and conduction). A similar "normalization" concept also applies to RyR2 stabilizers, which only prevent aberrant opening and diastolic Ca²⁺ leakage in diseased tissues, with no effect on normal function during systole. The different mechanisms of action of AA drugs may increase the therapeutic options available for the safe treatment of arrhythmias in a wide variety of pathophysiological situations.
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Affiliation(s)
- Jérôme Thireau
- Inserm U1046 Physiologie & Médecine Expérimentale du Cœur et des Muscles, Université Montpellier-1, Université Montpellier-2, 34295 Montpellier Cedex 5, France
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Betzenhauser MJ, Marks AR. Ryanodine receptor channelopathies. Pflugers Arch 2010; 460:467-80. [PMID: 20179962 PMCID: PMC2885589 DOI: 10.1007/s00424-010-0794-4] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 01/26/2010] [Accepted: 01/28/2010] [Indexed: 02/07/2023]
Abstract
Ryanodine receptors (RyR) are intracellular Ca2+-permeable channels that provide the sarcoplasmic reticulum Ca2+ release required for skeletal and cardiac muscle contractions. RyR1 underlies skeletal muscle contraction, and RyR2 fulfills this role in cardiac muscle. Over the past 20 years, numerous mutations in both RyR isoforms have been identified and linked to skeletal and cardiac diseases. Malignant hyperthermia, central core disease, and catecholaminergic polymorphic ventricular tachycardia have been genetically linked to mutations in either RyR1 or RyR2. Thus, RyR channelopathies are both of interest because they cause significant human diseases and provide model systems that can be studied to elucidate important structure-function relationships of these ion channels.
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Affiliation(s)
- Matthew J Betzenhauser
- Department of Physiology, Clyde and Helen Wu Center for Molecular Cardiology, Columbia University College of Physicians and Surgeons, 630 West 168th Street, New York, NY 10032, USA
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Andersson DC, Marks AR. Fixing ryanodine receptor Ca leak - a novel therapeutic strategy for contractile failure in heart and skeletal muscle. ACTA ACUST UNITED AC 2010; 7:e151-e157. [PMID: 21113427 DOI: 10.1016/j.ddmec.2010.09.009] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A critical component in regulating cardiac and skeletal muscle contractility is the release of Ca(2+) via ryanodine receptor (RyR) Ca(2+) release channels in the sarcoplasmic reticulum (SR). In heart failure and myopathy, the RyR has been found to be excessively phosphorylated or nitrosylated and depleted of the RyR-stabilizing protein calstabin (FK506 binding protein 12/12.6). This remodeling of the RyR channel complex results in an intracellular SR Ca(2+) leak and impaired contractility. Despite recent advances in heart failure treatment, there are still devastatingly high mortality rates with this disease. Moreover, pharmacological treatment for muscle weakness and myopathy is nearly nonexistent. A novel class of RyR-stabilizing drugs, rycals, which reduce Ca(2+) leak by stabilizing the RyR channels due to preservation of the RyR-calstabin interaction, have recently been shown to improve contractile function in both heart and skeletal muscle. This opens up a novel therapeutic strategy for the treatment of contractile failure in the cardiac and skeletal muscle.
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Affiliation(s)
- Daniel C Andersson
- Department of Physiology and Cellular Biophysics, Clyde and Helen Wu Center for Molecular Cardiology, College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA
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Thomas NL, Maxwell C, Mukherjee S, Williams AJ. Ryanodine receptor mutations in arrhythmia: The continuing mystery of channel dysfunction. FEBS Lett 2010; 584:2153-60. [PMID: 20132818 DOI: 10.1016/j.febslet.2010.01.057] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2010] [Revised: 01/27/2010] [Accepted: 01/29/2010] [Indexed: 11/13/2022]
Abstract
Mutations in RyR2 are causative of an inherited disorder which often results in sudden cardiac death. Dysfunctional channel behaviour has been the subject of many investigations varying from single channel analysis through to complex animal models. This review discusses recent advances in the field, describes the controversy surrounding the exact consequences of RyR2 mutation and how the disparate data may be reconciled. This heterogeneity of function with respect to the effects of polymorphisms, phosphorylation, cytosolic and luminal Ca(2+) as well as inter-domain interactions may have important implications for the recent pharmaceutical therapies which have been put forward. We surmise that a comprehensive characterisation of mutations on a case-by-case basis may be beneficial for the development of specifically targeted therapies.
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Affiliation(s)
- N Lowri Thomas
- Department of Cardiology, Wales Heart Research Institute, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, UK.
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