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Tao Y, Yao K, Wu J, Xu T, Lin J, Qin Y, Su D, Cai S, Yu W, Chen X. Intravenous anesthetics have differential effects on human potassium channels. Acta Biochim Biophys Sin (Shanghai) 2024; 56:1594-1603. [PMID: 40384046 PMCID: PMC11659785 DOI: 10.3724/abbs.2024151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/02/2024] [Indexed: 05/20/2025] Open
Abstract
General anesthetics are widely used in the clinic and greatly promote the development of surgery. However, the incidence of cardiovascular and respiratory complications caused by general anesthetics is still high, and the underlying mechanisms remain incompletely understood. Potassium channels are widely expressed in the heart and blood vessels and participate in regulating blood pressure, heart rate, and other physiological parameters. Whether they are directly affected by intravenous general anesthetics is unclear. Here, we independently express four classes of potassium channels, TASK-1, TASK-3, Kv1.5, Kv2.1, Kir2.1, SK1 and SK3, in Xenopus oocytes. The effects of propofol, pentobarbital and ketamine on these channels are evaluated by their current change. We find that propofol and ketamine potentiate TASK-3 and SK3 current respectively, while pentobarbital and ketamine inhibit SK1 current. To identify the key residues in TASK-3, SK1 and SK3 that interact with intravenous anesthetics, we predict homology models of the three channels and perform molecular docking simulations. The results show that propofol forms a hydrogen bond with Q126 of TASK-3, ketamine forms a hydrogen bond with S290 of SK1 and S467 of SK3, while pentobarbital forms hydrogen bonds with S330 and T358 of SK1. As these potassium channels are closely related to respiratory system regulation, cardiac rhythm and vasodilation, our study provides a new perspective for further study on the mechanism of general anesthetics-induced respiratory and circulatory side effects.
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Affiliation(s)
- Ying Tao
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
| | - Kejie Yao
- Institute of NeuroscienceState Key Laboratory of NeuroscienceCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China; University of Chinese Academy of SciencesBeijing101408China
| | - Jing Wu
- Department of Equipment and MaterialsBiomedical R&D Project TeamZhongshan HospitalFudan UniversityShanghai200031China
| | - Tian Xu
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
| | - Junhui Lin
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
| | - Yi Qin
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
| | - Diansan Su
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
| | - Shiqing Cai
- Institute of NeuroscienceState Key Laboratory of NeuroscienceCAS Center for Excellence in Brain Science and Intelligence TechnologyChinese Academy of SciencesShanghai 200031China; University of Chinese Academy of SciencesBeijing101408China
| | - Weifeng Yu
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
| | - Xuemei Chen
- Department of AnesthesiologyRenji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China
- Key Laboratory of Anesthesiology (Shanghai Jiao Tong University)Ministry of EducationShanghai200127China
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Müller ME, Petersenn F, Hackbarth J, Pfeiffer J, Gampp H, Frey N, Lugenbiel P, Thomas D, Rahm AK. Electrophysiological Effects of the Sodium-Glucose Co-Transporter-2 (SGLT2) Inhibitor Dapagliflozin on Human Cardiac Potassium Channels. Int J Mol Sci 2024; 25:5701. [PMID: 38891889 PMCID: PMC11172209 DOI: 10.3390/ijms25115701] [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: 04/26/2024] [Revised: 05/17/2024] [Accepted: 05/20/2024] [Indexed: 06/21/2024] Open
Abstract
The sodium-glucose co-transporter-2 (SGLT2) inhibitor dapagliflozin is increasingly used in the treatment of diabetes and heart failure. Dapagliflozin has been associated with reduced incidence of atrial fibrillation (AF) in clinical trials. We hypothesized that the favorable antiarrhythmic outcome of dapagliflozin use may be caused in part by previously unrecognized effects on atrial repolarizing potassium (K+) channels. This study was designed to assess direct pharmacological effects of dapagliflozin on cloned ion channels Kv11.1, Kv1.5, Kv4.3, Kir2.1, K2P2.1, K2P3.1, and K2P17.1, contributing to IKur, Ito, IKr, IK1, and IK2P K+ currents. Human channels coded by KCNH2, KCNA5, KCND3, KCNJ2, KCNK2, KCNK3, and KCNK17 were heterologously expressed in Xenopus laevis oocytes, and currents were recorded using the voltage clamp technique. Dapagliflozin (100 µM) reduced Kv11.1 and Kv1.5 currents, whereas Kir2.1, K2P2.1, and K2P17.1 currents were enhanced. The drug did not significantly affect peak current amplitudes of Kv4.3 or K2P3.1 K+ channels. Biophysical characterization did not reveal significant effects of dapagliflozin on current-voltage relationships of study channels. In conclusion, dapagliflozin exhibits direct functional interactions with human atrial K+ channels underlying IKur, IKr, IK1, and IK2P currents. Substantial activation of K2P2.1 and K2P17.1 currents could contribute to the beneficial antiarrhythmic outcome associated with the drug. Indirect or chronic effects remain to be investigated in vivo.
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Affiliation(s)
- Mara Elena Müller
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg University, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Finn Petersenn
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg University, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Juline Hackbarth
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Julia Pfeiffer
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Heike Gampp
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Norbert Frey
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg University, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Patrick Lugenbiel
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg University, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg University, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
| | - Ann-Kathrin Rahm
- Department of Cardiology, Medical University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany; (M.E.M.); (P.L.); (D.T.)
- HCR (Heidelberg Center for Heart Rhythm Disorders), University Hospital Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Heidelberg University, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany
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Saint-Martin Willer A, Santos-Gomes J, Adão R, Brás-Silva C, Eyries M, Pérez-Vizcaino F, Capuano V, Montani D, Antigny F. Physiological and pathophysiological roles of the KCNK3 potassium channel in the pulmonary circulation and the heart. J Physiol 2023; 601:3717-3737. [PMID: 37477289 DOI: 10.1113/jp284936] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 07/04/2023] [Indexed: 07/22/2023] Open
Abstract
Potassium channel subfamily K member 3 (KCNK3), encoded by the KCNK3 gene, is part of the two-pore domain potassium channel family, constitutively active at resting membrane potentials in excitable cells, including smooth muscle and cardiac cells. Several physiological and pharmacological mediators, such as intracellular signalling pathways, extracellular pH, hypoxia and anaesthetics, regulate KCNK3 channel function. Recent studies show that modulation of KCNK3 channel expression and function strongly influences pulmonary vascular cell and cardiomyocyte function. The altered activity of KCNK3 in pathological situations such as atrial fibrillation, pulmonary arterial hypertension and right ventricular dysfunction demonstrates the crucial role of KCNK3 in cardiovascular homeostasis. Furthermore, loss of function variants of KCNK3 have been identified in patients suffering from pulmonary arterial hypertension and atrial fibrillation. This review focuses on current knowledge of the role of the KCNK3 channel in pulmonary circulation and the heart, in healthy and pathological conditions.
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Affiliation(s)
- Anaïs Saint-Martin Willer
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France
- INSERM UMR_S 999 'Hypertension Pulmonaire: Physiopathologie et Innovation Thérapeutique', Hôpital Marie Lannelongue, Le Plessis-Robinson, France
| | - Joana Santos-Gomes
- Cardiovascular R&D Centre-UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Rui Adão
- Cardiovascular R&D Centre-UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine of the University of Porto, Porto, Portugal
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
- CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Carmen Brás-Silva
- Cardiovascular R&D Centre-UnIC@RISE, Department of Surgery and Physiology, Faculty of Medicine of the University of Porto, Porto, Portugal
| | - Mélanie Eyries
- Département de génétique, Assistance Publique-Hôpitaux de Paris, Hôpital Pitié-Salpêtrière, Sorbonne Université, Paris, France
- INSERM UMRS1166, ICAN - Institute of CardioMetabolism and Nutrition, Sorbonne Université, Paris, France
| | - Francisco Pérez-Vizcaino
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
- CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Véronique Capuano
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France
- INSERM UMR_S 999 'Hypertension Pulmonaire: Physiopathologie et Innovation Thérapeutique', Hôpital Marie Lannelongue, Le Plessis-Robinson, France
| | - David Montani
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France
- INSERM UMR_S 999 'Hypertension Pulmonaire: Physiopathologie et Innovation Thérapeutique', Hôpital Marie Lannelongue, Le Plessis-Robinson, France
- Assistance Publique - Hôpitaux de Paris (AP-HP), Service de Pneumologie et Soins Intensifs Respiratoires, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin-Bicêtre, France
| | - Fabrice Antigny
- Université Paris-Saclay, Faculté de Médecine, Le Kremlin-Bicêtre, France
- INSERM UMR_S 999 'Hypertension Pulmonaire: Physiopathologie et Innovation Thérapeutique', Hôpital Marie Lannelongue, Le Plessis-Robinson, France
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Fan X, Lu Y, Du G, Liu J. Advances in the Understanding of Two-Pore Domain TASK Potassium Channels and Their Potential as Therapeutic Targets. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238296. [PMID: 36500386 PMCID: PMC9736439 DOI: 10.3390/molecules27238296] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/09/2022] [Accepted: 11/15/2022] [Indexed: 11/29/2022]
Abstract
TWIK-related acid-sensitive K+ (TASK) channels, including TASK-1, TASK-3, and TASK-5, are important members of the two-pore domain potassium (K2P) channel family. TASK-5 is not functionally expressed in the recombinant system. TASK channels are very sensitive to changes in extracellular pH and are active during all membrane potential periods. They are similar to other K2P channels in that they can create and use background-leaked potassium currents to stabilize resting membrane conductance and repolarize the action potential of excitable cells. TASK channels are expressed in both the nervous system and peripheral tissues, including excitable and non-excitable cells, and are widely engaged in pathophysiological phenomena, such as respiratory stimulation, pulmonary hypertension, arrhythmia, aldosterone secretion, cancers, anesthesia, neurological disorders, glucose homeostasis, and visual sensitivity. Therefore, they are important targets for innovative drug development. In this review, we emphasized the recent advances in our understanding of the biophysical properties, gating profiles, and biological roles of TASK channels. Given the different localization ranges and biologically relevant functions of TASK-1 and TASK-3 channels, the development of compounds that selectively target TASK-1 and TASK-3 channels is also summarized based on data reported in the literature.
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Affiliation(s)
- Xueming Fan
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang 550002, China
| | - Yongzhi Lu
- Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510700, China
| | - Guizhi Du
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China
- Correspondence: (G.D.); (J.L.)
| | - Jin Liu
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China
- Correspondence: (G.D.); (J.L.)
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Two-Pore-Domain Potassium (K 2P-) Channels: Cardiac Expression Patterns and Disease-Specific Remodelling Processes. Cells 2021; 10:cells10112914. [PMID: 34831137 PMCID: PMC8616229 DOI: 10.3390/cells10112914] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/18/2021] [Accepted: 10/22/2021] [Indexed: 12/23/2022] Open
Abstract
Two-pore-domain potassium (K2P-) channels conduct outward K+ currents that maintain the resting membrane potential and modulate action potential repolarization. Members of the K2P channel family are widely expressed among different human cell types and organs where they were shown to regulate important physiological processes. Their functional activity is controlled by a broad variety of different stimuli, like pH level, temperature, and mechanical stress but also by the presence of lipids or pharmacological agents. In patients suffering from cardiovascular diseases, alterations in K2P-channel expression and function have been observed, suggesting functional significance and a potential therapeutic role of these ion channels. For example, upregulation of atrial specific K2P3.1 (TASK-1) currents in atrial fibrillation (AF) patients was shown to contribute to atrial action potential duration shortening, a key feature of AF-associated atrial electrical remodelling. Therefore, targeting K2P3.1 (TASK-1) channels might constitute an intriguing strategy for AF treatment. Further, mechanoactive K2P2.1 (TREK-1) currents have been implicated in the development of cardiac hypertrophy, cardiac fibrosis and heart failure. Cardiovascular expression of other K2P channels has been described, functional evidence in cardiac tissue however remains sparse. In the present review, expression, function, and regulation of cardiovascular K2P channels are summarized and compared among different species. Remodelling patterns, observed in disease models are discussed and compared to findings from clinical patients to assess the therapeutic potential of K2P channels.
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Kraft M, Büscher A, Wiedmann F, L’hoste Y, Haefeli WE, Frey N, Katus HA, Schmidt C. Current Drug Treatment Strategies for Atrial Fibrillation and TASK-1 Inhibition as an Emerging Novel Therapy Option. Front Pharmacol 2021; 12:638445. [PMID: 33897427 PMCID: PMC8058608 DOI: 10.3389/fphar.2021.638445] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 01/21/2021] [Indexed: 12/19/2022] Open
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia with a prevalence of up to 4% and an upwards trend due to demographic changes. It is associated with an increase in mortality and stroke incidences. While stroke risk can be significantly reduced through anticoagulant therapy, adequate treatment of other AF related symptoms remains an unmet medical need in many cases. Two main treatment strategies are available: rate control that modulates ventricular heart rate and prevents tachymyopathy as well as rhythm control that aims to restore and sustain sinus rhythm. Rate control can be achieved through drugs or ablation of the atrioventricular node, rendering the patient pacemaker-dependent. For rhythm control electrical cardioversion and pharmacological cardioversion can be used. While electrical cardioversion requires fasting and sedation of the patient, antiarrhythmic drugs have other limitations. Most antiarrhythmic drugs carry a risk for pro-arrhythmic effects and are contraindicated in patients with structural heart diseases. Furthermore, catheter ablation of pulmonary veins can be performed with its risk of intraprocedural complications and varying success. In recent years TASK-1 has been introduced as a new target for AF therapy. Upregulation of TASK-1 in AF patients contributes to prolongation of the action potential duration. In a porcine model of AF, TASK-1 inhibition by gene therapy or pharmacological compounds induced cardioversion to sinus rhythm. The DOxapram Conversion TO Sinus rhythm (DOCTOS)-Trial will reveal whether doxapram, a potent TASK-1 inhibitor, can be used for acute cardioversion of persistent and paroxysmal AF in patients, potentially leading to a new treatment option for AF.
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Affiliation(s)
- Manuel Kraft
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany
- HCR, Heidelberg Center for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Antonius Büscher
- Clinic for Cardiology II: Electrophysiology, University Hospital Münster, Münster, Germany
| | - Felix Wiedmann
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany
- HCR, Heidelberg Center for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Yannick L’hoste
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
- HCR, Heidelberg Center for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Walter E. Haefeli
- Department of Clinical Pharmacology and Pharmacoepidemiology, University of Heidelberg, Heidelberg, Germany
| | - Norbert Frey
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany
- HCR, Heidelberg Center for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Hugo A. Katus
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany
- HCR, Heidelberg Center for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Constanze Schmidt
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
- DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany
- HCR, Heidelberg Center for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
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Wiedmann F, Rinné S, Donner B, Decher N, Katus HA, Schmidt C. Mechanosensitive TREK-1 two-pore-domain potassium (K 2P) channels in the cardiovascular system. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 159:126-135. [PMID: 32553901 DOI: 10.1016/j.pbiomolbio.2020.05.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 04/01/2020] [Accepted: 05/11/2020] [Indexed: 12/12/2022]
Abstract
TWIK-related K+ channel (TREK-1) two-pore-domain potassium (K2P) channels mediate background potassium currents and regulate cellular excitability in many different types of cells. Their functional activity is controlled by a broad variety of different physiological stimuli, such as temperature, extracellular or intracellular pH, lipids and mechanical stress. By linking cellular excitability to mechanical stress, TREK-1 currents might be important to mediate parts of the mechanoelectrical feedback described in the heart. Furthermore, TREK-1 currents might contribute to the dysregulation of excitability in the heart in pathophysiological situations, such as those caused by abnormal stretch or ischaemia-associated cell swelling, thereby contributing to arrhythmogenesis. In this review, we focus on the functional role of TREK-1 in the heart and its putative contribution to cardiac mechanoelectrical coupling. Its cardiac expression among different species is discussed, alongside with functional evidence for TREK-1 currents in cardiomyocytes. In addition, evidence for the involvement of TREK-1 currents in different cardiac arrhythmias, such as atrial fibrillation or ventricular tachycardia, is summarized. Furthermore, the role of TREK-1 and its interaction partners in the regulation of the cardiac heart rate is reviewed. Finally, we focus on the significance of TREK-1 in the development of cardiac hypertrophy, cardiac fibrosis and heart failure.
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Affiliation(s)
- Felix Wiedmann
- Department of Cardiology, University Hospital Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany; HCR, Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - Philipps-University Marburg, Marburg, Germany
| | - Birgit Donner
- Pediatric Cardiology, University Children's Hospital Basel (UKBB), University of Basel, Basel, Switzerland
| | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior - Philipps-University Marburg, Marburg, Germany
| | - Hugo A Katus
- Department of Cardiology, University Hospital Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany; HCR, Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany
| | - Constanze Schmidt
- Department of Cardiology, University Hospital Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany; HCR, Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany.
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8
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Staudacher I, Seehausen S, Illg C, Lugenbiel P, Schweizer PA, Katus HA, Thomas D. Cardiac K2P13.1 (THIK-1) two-pore-domain K+ channels: Pharmacological regulation and remodeling in atrial fibrillation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 144:128-138. [DOI: 10.1016/j.pbiomolbio.2018.06.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/28/2018] [Accepted: 06/25/2018] [Indexed: 01/30/2023]
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Peyronnet R, Ravens U. Atria-selective antiarrhythmic drugs in need of alliance partners. Pharmacol Res 2019; 145:104262. [PMID: 31059791 DOI: 10.1016/j.phrs.2019.104262] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/30/2019] [Accepted: 05/03/2019] [Indexed: 12/15/2022]
Abstract
Atria-selective antiarrhythmic drugs in need of alliance partners. Guideline-based treatment of atrial fibrillation (AF) comprises prevention of thromboembolism and stroke, as well as antiarrhythmic therapy by drugs, electrical rhythm conversion, ablation and surgical procedures. Conventional antiarrhythmic drugs are burdened with unwanted side effects including a propensity of triggering life-threatening ventricular fibrillation. In order to solve this therapeutic dilemma, 'atria-selective' antiarrhythmic drugs have been developed for the treatment of supraventricular arrhythmias. These drugs are designed to aim at atrial targets, taking advantage of differences in atrial and ventricular ion channel expression and function. However it is not clear, whether such drugs are sufficiently antiarrhythmic or whether they are in need of an alliance partner for clinical efficacy. Atria-selective Na+ channel blockers display fast dissociation kinetics and high binding affinity to inactivated channels. Compounds targeting atria-selective K+ channels include blockers of ultra rapid delayed rectifier (Kv1.5) or acetylcholine-activated inward rectifier K+ channels (Kir3.x), inward rectifying K+ channels (Kir2.x), Ca2+-activated K+ channels of small conductance (SK), weakly rectifying two-pore domain K+ channels (K2P), and transient receptor potential channels (TRP). Despite good antiarrhythmic data from in-vitro and animal model experiments, clinical efficacy of atria-selective antiarrhythmic drugs remains to be demonstrated. In the present review we will briefly summarize the novel compounds and their proposed antiarrhythmic action. In addition, we will discuss the evidence for putative improvement of antiarrhythmic efficacy and potency by addressing multiple pathophysiologically relevant targets as possible alliance partners.
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Affiliation(s)
- Rémi Peyronnet
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg Bad Krozingen, Medical Center, University of Freiburg, Freiburg, Germany; Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ursula Ravens
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg Bad Krozingen, Medical Center, University of Freiburg, Freiburg, Germany; Institute of Physiology, Medical Faculty TU Dresden, Dresden, Germany.
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10
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Jones SA, Walton RD, Morton M, Lancaster MK. K 2p 3.1 protein is expressed as a transmural gradient across the rat left ventricular free wall. J Cardiovasc Electrophysiol 2018; 30:383-391. [PMID: 30516300 PMCID: PMC6446730 DOI: 10.1111/jce.13805] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 11/08/2018] [Accepted: 11/15/2018] [Indexed: 12/25/2022]
Abstract
Introduction K2p3.1, also known as TASK‐1, is a twin‐pore acid‐sensitive repolarizing K+ channel, responsible for a background potassium current that significantly contributes to setting the resting membrane potential of cardiac myocytes. Inhibition of IK2p3.1 alters cardiac repolarization and is proarrhythmogenic. In this study, we have examined the expression of K2p3.1 and function of this channel in tissue and myocytes from across the left ventricular free wall. Methods and Results Using fluorescence immunocytochemistry, the expression of K2p3.1 protein in myocytes from the subendocardial region was found to be twice (205% ± 13.5%) that found in myocytes from the subepicardial region of the left ventricle (100% ± 5.3%). The left ventricular free wall exhibited a marked transmural gradient of K2p3.1 protein expression. Western blot analysis confirmed significantly higher K2p3.1 protein expression in subendocardial tissue (156% ± 2.5%) than subepicardial tissue (100% ± 5.0%). However, there was no difference in K2p3.1 messenger RNA expression. Whole‐cell patch clamp identified IK2p3.1 current density to be significantly greater in myocytes isolated from the subendocardium (7.66 ± 0.53 pA/pF) compared with those from the subepicardium (3.47 ± 0.74 pA/pF). Conclusions This is the first study to identify a transmural gradient of K2p3.1 in the left ventricle. This gradient has implications for understanding ventricular arrhythmogenesis under conditions of ischemia but also in response to other modulatory factors, such as adrenergic stimulation and the presence of anesthetics that inhibits or activates this channel.
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Affiliation(s)
- Sandra A Jones
- Department of Biomedical Sciences, Department Faculty of Health Sciences, University of Hull, Hull, UK
| | - Richard D Walton
- Centre de Recherche Cardio-Thoracique de Bordeaux U1045, Université de Bordeaux, Bordeaux, France.,Inserm, Centre de Recherche Cardio-Thoracique de Bordeaux, Bordeaux, France.,L'Institut de Rythmologie et Modélisation Cardiaque LIRYC, Fondation Bordeaux Université, Bordeaux, France
| | | | - Matthew K Lancaster
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds, UK
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11
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Vagos M, van Herck IGM, Sundnes J, Arevalo HJ, Edwards AG, Koivumäki JT. Computational Modeling of Electrophysiology and Pharmacotherapy of Atrial Fibrillation: Recent Advances and Future Challenges. Front Physiol 2018; 9:1221. [PMID: 30233399 PMCID: PMC6131668 DOI: 10.3389/fphys.2018.01221] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/13/2018] [Indexed: 12/19/2022] Open
Abstract
The pathophysiology of atrial fibrillation (AF) is broad, with components related to the unique and diverse cellular electrophysiology of atrial myocytes, structural complexity, and heterogeneity of atrial tissue, and pronounced disease-associated remodeling of both cells and tissue. A major challenge for rational design of AF therapy, particularly pharmacotherapy, is integrating these multiscale characteristics to identify approaches that are both efficacious and independent of ventricular contraindications. Computational modeling has long been touted as a basis for achieving such integration in a rapid, economical, and scalable manner. However, computational pipelines for AF-specific drug screening are in their infancy, and while the field is progressing quite rapidly, major challenges remain before computational approaches can fill the role of workhorse in rational design of AF pharmacotherapies. In this review, we briefly detail the unique aspects of AF pathophysiology that determine requirements for compounds targeting AF rhythm control, with emphasis on delimiting mechanisms that promote AF triggers from those providing substrate or supporting reentry. We then describe modeling approaches that have been used to assess the outcomes of drugs acting on established AF targets, as well as on novel promising targets including the ultra-rapidly activating delayed rectifier potassium current, the acetylcholine-activated potassium current and the small conductance calcium-activated potassium channel. Finally, we describe how heterogeneity and variability are being incorporated into AF-specific models, and how these approaches are yielding novel insights into the basic physiology of disease, as well as aiding identification of the important molecular players in the complex AF etiology.
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Affiliation(s)
- Márcia Vagos
- Computational Physiology Department, Simula Research Laboratory, Lysaker, Norway
- Department of Informatics, University of Oslo, Oslo, Norway
| | - Ilsbeth G. M. van Herck
- Computational Physiology Department, Simula Research Laboratory, Lysaker, Norway
- Department of Informatics, University of Oslo, Oslo, Norway
| | - Joakim Sundnes
- Computational Physiology Department, Simula Research Laboratory, Lysaker, Norway
- Center for Cardiological Innovation, Oslo, Norway
| | - Hermenegild J. Arevalo
- Computational Physiology Department, Simula Research Laboratory, Lysaker, Norway
- Center for Cardiological Innovation, Oslo, Norway
| | - Andrew G. Edwards
- Computational Physiology Department, Simula Research Laboratory, Lysaker, Norway
- Center for Cardiological Innovation, Oslo, Norway
| | - Jussi T. Koivumäki
- BioMediTech Institute and Faculty of Biomedical Sciences and Engineering, Tampere University of Technology, Tampere, Finland
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
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12
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Staudacher I, Illg C, Gierten J, Seehausen S, Schweizer PA, Katus HA, Thomas D. Identification and functional characterization of zebrafish K 2P 17.1 (TASK-4, TALK-2) two-pore-domain K + channels. Eur J Pharmacol 2018; 831:94-102. [DOI: 10.1016/j.ejphar.2018.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/04/2018] [Accepted: 05/08/2018] [Indexed: 12/12/2022]
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13
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Calvo D, Filgueiras-Rama D, Jalife J. Mechanisms and Drug Development in Atrial Fibrillation. Pharmacol Rev 2018; 70:505-525. [PMID: 29921647 PMCID: PMC6010660 DOI: 10.1124/pr.117.014183] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Atrial fibrillation is a highly prevalent cardiac arrhythmia and the most important cause of embolic stroke. Although genetic studies have identified an increasing assembly of AF-related genes, the impact of these genetic discoveries is yet to be realized. In addition, despite more than a century of research and speculation, the molecular and cellular mechanisms underlying AF have not been established, and therapy for AF, particularly persistent AF, remains suboptimal. Current antiarrhythmic drugs are associated with a significant rate of adverse events, particularly proarrhythmia, which may explain why many highly symptomatic AF patients are not receiving any rhythm control therapy. This review focuses on recent advances in AF research, including its epidemiology, genetics, and pathophysiological mechanisms. We then discuss the status of antiarrhythmic drug therapy for AF today, reviewing molecular mechanisms, and the possible clinical use of some of the new atrial-selective antifibrillatory agents, as well as drugs that target atrial remodeling, inflammation and fibrosis, which are being tested as upstream therapies to prevent AF perpetuation. Altogether, the objective is to highlight the magnitude and endemic dimension of AF, which requires a significant effort to develop new and effective antiarrhythmic drugs, but also improve AF prevention and treatment of risk factors that are associated with AF complications.
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Affiliation(s)
- David Calvo
- Department of Cardiology, Arrhythmia Unit, Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain (D.C.); Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain (D.F.-R., J.J.); Department of Cardiology, Arrhythmia Unit, Hospital Clínico Universitario San Carlos, Madrid, Spain (D.F.-R.); Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain (D.F.-R., J.J.); and Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (J.J.)
| | - David Filgueiras-Rama
- Department of Cardiology, Arrhythmia Unit, Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain (D.C.); Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain (D.F.-R., J.J.); Department of Cardiology, Arrhythmia Unit, Hospital Clínico Universitario San Carlos, Madrid, Spain (D.F.-R.); Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain (D.F.-R., J.J.); and Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (J.J.)
| | - José Jalife
- Department of Cardiology, Arrhythmia Unit, Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain (D.C.); Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain (D.F.-R., J.J.); Department of Cardiology, Arrhythmia Unit, Hospital Clínico Universitario San Carlos, Madrid, Spain (D.F.-R.); Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain (D.F.-R., J.J.); and Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (J.J.)
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14
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Schmidt C, Wiedmann F, Gaubatz AR, Ratte A, Katus HA, Thomas D. New Targets for Old Drugs: Cardiac Glycosides Inhibit Atrial-Specific K 2P3.1 (TASK-1) Channels. J Pharmacol Exp Ther 2018; 365:614-623. [PMID: 29643254 DOI: 10.1124/jpet.118.247692] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 04/04/2018] [Indexed: 02/06/2023] Open
Abstract
Cardiac glycosides have been used in the treatment of arrhythmias for more than 200 years. Two-pore-domain (K2P) potassium channels regulate cardiac action potential repolarization. Recently, K2P3.1 [tandem of P domains in a weak inward rectifying K+ channel (TWIK)-related acid-sensitive K+ channel (TASK)-1] has been implicated in atrial fibrillation pathophysiology and was suggested as an atrial-selective antiarrhythmic drug target. We hypothesized that blockade of cardiac K2P channels contributes to the mechanism of action of digitoxin and digoxin. All functional human K2P channels were screened for interactions with cardiac glycosides. Human K2P channel subunits were expressed in Xenopus laevis oocytes, and voltage clamp electrophysiology was used to record K+ currents. Digitoxin significantly inhibited K2P3.1 and K2P16.1 channels. By contrast, digoxin displayed isolated inhibitory effects on K2P3.1. K2P3.1 outward currents were reduced by 80% (digitoxin, 1 Hz) and 78% (digoxin, 1 Hz). Digitoxin inhibited K2P3.1 currents with an IC50 value of 7.4 µM. Outward rectification properties of the channel were not affected. Mutagenesis studies revealed that amino acid residues located at the cytoplasmic site of the K2P3.1 channel pore form parts of a molecular binding site for cardiac glycosides. In conclusion, cardiac glycosides target human K2P channels. The antiarrhythmic significance of repolarizing atrial K2P3.1 current block by digoxin and digitoxin requires validation in translational and clinical studies.
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Affiliation(s)
- Constanze Schmidt
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); and German Centre for Cardiovascular Research, Heidelberg/Mannheim Partner Site, University of Heidelberg, Heidelberg, Germany (C.S., F.W., H.A.K., D.T.)
| | - Felix Wiedmann
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); and German Centre for Cardiovascular Research, Heidelberg/Mannheim Partner Site, University of Heidelberg, Heidelberg, Germany (C.S., F.W., H.A.K., D.T.)
| | - Anne-Rike Gaubatz
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); and German Centre for Cardiovascular Research, Heidelberg/Mannheim Partner Site, University of Heidelberg, Heidelberg, Germany (C.S., F.W., H.A.K., D.T.)
| | - Antonius Ratte
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); and German Centre for Cardiovascular Research, Heidelberg/Mannheim Partner Site, University of Heidelberg, Heidelberg, Germany (C.S., F.W., H.A.K., D.T.)
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); and German Centre for Cardiovascular Research, Heidelberg/Mannheim Partner Site, University of Heidelberg, Heidelberg, Germany (C.S., F.W., H.A.K., D.T.)
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); Heidelberg Center for Heart Rhythm Disorders, University Hospital Heidelberg, Heidelberg, Germany (C.S., F.W., A.-R.G., A.R., H.A.K., D.T.); and German Centre for Cardiovascular Research, Heidelberg/Mannheim Partner Site, University of Heidelberg, Heidelberg, Germany (C.S., F.W., H.A.K., D.T.)
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15
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Ravens U. Atrial-selective K + channel blockers: potential antiarrhythmic drugs in atrial fibrillation? Can J Physiol Pharmacol 2017; 95:1313-1318. [PMID: 28738160 DOI: 10.1139/cjpp-2017-0024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In the wake of demographic change in Western countries, atrial fibrillation has reached an epidemiological scale, yet current strategies for drug treatment of the arrhythmia lack sufficient efficacy and safety. In search of novel medications, atrial-selective drugs that specifically target atrial over other cardiac functions have been developed. Here, I will address drugs acting on potassium (K+) channels that are either predominantly expressed in atria or possess electrophysiological properties distinct in atria from ventricles. These channels include the ultra-rapidly activating, delayed outward-rectifying Kv1.5 channel conducting IKur, the acetylcholine-activated inward-rectifying Kir3.1/Kir3.4 channel conducting IK,ACh, the Ca2+-activated K+ channels of small conductance (SK) conducting ISK, and the two-pore domain K+ (K2P) channels (tandem of P domains, weak inward-rectifying K+ channels (TWIK-1), TWIK-related acid-sensitive K+ channels (TASK-1 and TASK-3)) that are responsible for voltage-independent background currents ITWIK-1, ITASK-1, and ITASK-3. Direct drug effects on these channels are described and their putative value in treatment of atrial fibrillation is discussed. Although many potential drug targets have emerged in the process of unravelling details of the pathophysiological mechanisms responsible for atrial fibrillation, we do not know whether novel antiarrhythmic drugs will be more successful when modulating many targets or a single specific one. The answer to this riddle can only be solved in a clinical context.
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Affiliation(s)
- Ursula Ravens
- Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg - Bad Krozingen, University of Freiburg, Germany; Institute of Physiology, Medical Faculty Carl Gustav Carus, TU Dresden, Germany.,Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg - Bad Krozingen, University of Freiburg, Germany; Institute of Physiology, Medical Faculty Carl Gustav Carus, TU Dresden, Germany
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16
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Schmidt C, Wiedmann F, Kallenberger SM, Ratte A, Schulte JS, Scholz B, Müller FU, Voigt N, Zafeiriou MP, Ehrlich JR, Tochtermann U, Veres G, Ruhparwar A, Karck M, Katus HA, Thomas D. Stretch-activated two-pore-domain (K 2P) potassium channels in the heart: Focus on atrial fibrillation and heart failure. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017; 130:233-243. [PMID: 28526353 DOI: 10.1016/j.pbiomolbio.2017.05.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 05/11/2017] [Accepted: 05/15/2017] [Indexed: 12/18/2022]
Abstract
Two-pore-domain potassium (K2P) channels modulate cellular excitability. The significance of stretch-activated cardiac K2P channels (K2P2.1, TREK-1, KCNK2; K2P4.1, TRAAK, KCNK4; K2P10.1, TREK-2, KCNK10) in heart disease has not been elucidated in detail. The aim of this work was to assess expression and remodeling of mechanosensitive K2P channels in atrial fibrillation (AF) and heart failure (HF) patients in comparison to murine models. Cardiac K2P channel levels were quantified in atrial (A) and ventricular (V) tissue obtained from patients undergoing open heart surgery. In addition, control mice and mouse models of AF (cAMP-response element modulator (CREM)-IbΔC-X transgenic animals) or HF (cardiac dysfunction induced by transverse aortic constriction, TAC) were employed. Human and murine KCNK2 displayed highest mRNA abundance among mechanosensitive members of the K2P channel family (V > A). Disease-associated K2P2.1 remodeling was studied in detail. In patients with impaired left ventricular function, atrial KCNK2 (K2P2.1) mRNA and protein expression was significantly reduced. In AF subjects, downregulation of atrial and ventricular KCNK2 (K2P2.1) mRNA and protein levels was observed. AF-associated suppression of atrial Kcnk2 (K2P2.1) mRNA and protein was recapitulated in CREM-transgenic mice. Ventricular Kcnk2 expression was not significantly altered in mouse models of disease. In conclusion, mechanosensitive K2P2.1 and K2P10.1 K+ channels are expressed throughout the heart. HF- and AF-associated downregulation of KCNK2 (K2P2.1) mRNA and protein levels suggest a mechanistic contribution to cardiac arrhythmogenesis.
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Affiliation(s)
- Constanze Schmidt
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg / Mannheim, University of Heidelberg, Germany
| | - Felix Wiedmann
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg / Mannheim, University of Heidelberg, Germany
| | - Stefan M Kallenberger
- Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Institute for Pharmacy and Molecular Biotechnology (IPMB) and BioQuant, Heidelberg University, Heidelberg, Germany
| | - Antonius Ratte
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
| | - Jan S Schulte
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Beatrix Scholz
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Frank Ulrich Müller
- Institute of Pharmacology and Toxicology, University of Münster, Münster, Germany
| | - Niels Voigt
- Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Georg-August University Göttingen, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Germany
| | - Maria-Patapia Zafeiriou
- Institute of Pharmacology and Toxicology, University Medical Center Göttingen, Georg-August University Göttingen, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Germany
| | - Joachim R Ehrlich
- Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany; Department of Cardiology, St. Josefs-Hospital, Wiesbaden, Germany
| | - Ursula Tochtermann
- Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany
| | - Gábor Veres
- Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany
| | - Arjang Ruhparwar
- Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany
| | - Matthias Karck
- Department of Cardiac Surgery, University of Heidelberg, Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg / Mannheim, University of Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany; DZHK (German Center for Cardiovascular Research), Partner Site Heidelberg / Mannheim, University of Heidelberg, Germany.
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17
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Abstract
Despite the epidemiological scale of atrial fibrillation, current treatment strategies are of limited efficacy and safety. Ideally, novel drugs should specifically correct the pathophysiological mechanisms responsible for atrial fibrillation with no other cardiac or extracardiac actions. Atrial-selective drugs are directed toward cellular targets with sufficiently different characteristics in atria and ventricles to modify only atrial function. Several potassium (K+) channels with either predominant expression in atria or distinct electrophysiological properties in atria and ventricles can serve as atrial-selective drug targets. These channels include the ultra-rapidly activating, delayed outward-rectifying Kv1.5 channel conducting IKur, the acetylcholine-activated inward-rectifying Kir3.1/Kir3.4 channel conducting IK,ACh, the Ca2+-activated K+ channels of small conductance (SK) conducting ISK, and the two pore domain K+ (K2P) channels TWIK-1, TASK-1 and TASK-3 that are responsible for voltage-independent background currents ITWIK-1, ITASK-1, and ITASK-3. Here, we briefly review the characteristics of these K+ channels and their roles in atrial fibrillation. The antiarrhythmic potential of drugs targeting the described channels is discussed as well as their putative value in treatment of atrial fibrillation.
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Affiliation(s)
- Ursula Ravens
- Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Freiburg, Germany; Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Freiburg, Germany; Department of Physiology, Medical Faculty Carl-Gustav-Carus, TU Dresden, Dresden, Germany.
| | - Katja E Odening
- Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg-Bad Krozingen, Freiburg, Germany; Department of Cardiology and Angiology I, University Heart Center Freiburg-Bad Krozingen, Freiburg, Germany
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18
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Therapeutic targeting of two-pore-domain potassium (K(2P)) channels in the cardiovascular system. Clin Sci (Lond) 2016; 130:643-50. [PMID: 26993052 DOI: 10.1042/cs20150533] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The improvement of treatment strategies in cardiovascular medicine is an ongoing process that requires constant optimization. The ability of a therapeutic intervention to prevent cardiovascular pathology largely depends on its capacity to suppress the underlying mechanisms. Attenuation or reversal of disease-specific pathways has emerged as a promising paradigm, providing a mechanistic rationale for patient-tailored therapy. Two-pore-domain K(+) (K(2P)) channels conduct outward K(+) currents that stabilize the resting membrane potential and facilitate action potential repolarization. K(2P) expression in the cardiovascular system and polymodal K2P current regulation suggest functional significance and potential therapeutic roles of the channels. Recent work has focused primarily on K(2P)1.1 [tandem of pore domains in a weak inwardly rectifying K(+) channel (TWIK)-1], K(2P)2.1 [TWIK-related K(+) channel (TREK)-1], and K(2P)3.1 [TWIK-related acid-sensitive K(+) channel (TASK)-1] channels and their role in heart and vessels. K(2P) currents have been implicated in atrial and ventricular arrhythmogenesis and in setting the vascular tone. Furthermore, the association of genetic alterations in K(2P)3.1 channels with atrial fibrillation, cardiac conduction disorders and pulmonary arterial hypertension demonstrates the relevance of the channels in cardiovascular disease. The function, regulation and clinical significance of cardiovascular K(2P) channels are summarized in the present review, and therapeutic options are emphasized.
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Abstract
Any disturbance of electrical impulse formation in the heart and of impulse conduction or action potential (AP) repolarization can lead to rhythm disorders. Potassium (K(+)) channels play a prominent role in the AP repolarization process. In this review we describe the causes and mechanisms of proarrhythmic effects that arise as a response to blockers of cardiac K(+) channels. The largest and chemically most diverse groups of compound targets are Kv11.1 (hERG) and Kv7.1 (KvLQT1) channels. Finally, the proarrhythmic propensity of atrial-selective K(+) blockers inhibiting Kv1.5, Kir3.1/3.4, SK, and K2P channels is discussed.
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Affiliation(s)
- Lasse Skibsbye
- Danish Arrhythmia Research Centre, Faculty of Health and Medical Sciences, University of Copenhagen, 3 Blegdamsvej, 3 Copenhagen N DK-2200, Denmark
| | - Ursula Ravens
- Department of Pharmacology and Toxicology, Medical Faculty Carl Gustav Carus, Institut für Pharmakologie und Toxikologie, TU Dresden, Fetscherstrasse 74, Dresden D-01307, Germany.
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20
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Abstract
Atrial fibrillation (AF) is associated with increased morbidity and mortality. Atrial-selective potassium (K(+)) channel blockers may represent a novel therapeutic target. The best validated atrial-specific ion currents are the acetylcholine-activated inward-rectifier K(+) current IK,ACh and ultrarapidly activating delayed-rectifier K(+) current IKur. Two-pore domain and small-conductance Ca(2+)-activated K(+) channels and Kv1.1 channels may also contribute to the atrial repolarization. We review the molecular and electrophysiologic characteristics of atrial-selective K(+) channels and their potential pathophysiologic role in AF. We summarize currently available K(+) channel blockers focusing on the most important compounds.
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Affiliation(s)
- Niels Voigt
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Hufelandstr. 55, Essen 45122, Germany
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, University Duisburg-Essen, Hufelandstr. 55, Essen 45122, Germany.
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21
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Hancox JC, James AF, Marrion NV, Zhang H, Thomas D. Novel ion channel targets in atrial fibrillation. Expert Opin Ther Targets 2016; 20:947-58. [DOI: 10.1517/14728222.2016.1159300] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Jules C. Hancox
- School of Physiology, Pharmacology and Neuroscience, University Walk, Bristol, UK
| | - Andrew F. James
- School of Physiology, Pharmacology and Neuroscience, University Walk, Bristol, UK
| | - Neil V. Marrion
- School of Physiology, Pharmacology and Neuroscience, University Walk, Bristol, UK
| | - Henggui Zhang
- Biological Physics Group, School of Physics and Astronomy, University of Manchester, Manchester, United Kingdom
| | - Dierk Thomas
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany
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Chokshi RH, Larsen AT, Bhayana B, Cotten JF. Breathing Stimulant Compounds Inhibit TASK-3 Potassium Channel Function Likely by Binding at a Common Site in the Channel Pore. Mol Pharmacol 2015; 88:926-34. [PMID: 26268529 PMCID: PMC4613942 DOI: 10.1124/mol.115.100107] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 08/11/2015] [Indexed: 11/22/2022] Open
Abstract
Compounds PKTHPP (1-{1-[6-(biphenyl-4-ylcarbonyl)-5,6,7,8-tetrahydropyrido[4,3-d]-pyrimidin-4-yl]piperidin-4-yl}propan-1-one), A1899 (2''-[(4-methoxybenzoylamino)methyl]biphenyl-2-carboxylic acid 2,4-difluorobenzylamide), and doxapram inhibit TASK-1 (KCNK3) and TASK-3 (KCNK9) tandem pore (K2P) potassium channel function and stimulate breathing. To better understand the molecular mechanism(s) of action of these drugs, we undertook studies to identify amino acid residues in the TASK-3 protein that mediate this inhibition. Guided by homology modeling and molecular docking, we hypothesized that PKTHPP and A1899 bind in the TASK-3 intracellular pore. To test our hypothesis, we mutated each residue in or near the predicted PKTHPP and A1899 binding site (residues 118-128 and 228-248), individually, to a negatively charged aspartate. We quantified each mutation's effect on TASK-3 potassium channel concentration response to PKTHPP. Studies were conducted on TASK-3 transiently expressed in Fischer rat thyroid epithelial monolayers; channel function was measured in an Ussing chamber. TASK-3 pore mutations at residues 122 (L122D, E, or K) and 236 (G236D) caused the IC50 of PKTHPP to increase more than 1000-fold. TASK-3 mutants L122D, G236D, L239D, and V242D were resistant to block by PKTHPP, A1899, and doxapram. Our data are consistent with a model in which breathing stimulant compounds PKTHPP, A1899, and doxapram inhibit TASK-3 function by binding at a common site within the channel intracellular pore region, although binding outside the channel pore cannot yet be excluded.
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Affiliation(s)
- Rikki H Chokshi
- Department of Anesthesia, Critical Care, and Pain Medicine (R.H.C., J.F.C.), Center for Computational and Integrative Biology, and Department of Molecular Biology (A.T.L.), and Department of Dermatology (B.B.), Massachusetts General Hospital, Boston, Massachusetts
| | - Aaron T Larsen
- Department of Anesthesia, Critical Care, and Pain Medicine (R.H.C., J.F.C.), Center for Computational and Integrative Biology, and Department of Molecular Biology (A.T.L.), and Department of Dermatology (B.B.), Massachusetts General Hospital, Boston, Massachusetts
| | - Brijesh Bhayana
- Department of Anesthesia, Critical Care, and Pain Medicine (R.H.C., J.F.C.), Center for Computational and Integrative Biology, and Department of Molecular Biology (A.T.L.), and Department of Dermatology (B.B.), Massachusetts General Hospital, Boston, Massachusetts
| | - Joseph F Cotten
- Department of Anesthesia, Critical Care, and Pain Medicine (R.H.C., J.F.C.), Center for Computational and Integrative Biology, and Department of Molecular Biology (A.T.L.), and Department of Dermatology (B.B.), Massachusetts General Hospital, Boston, Massachusetts
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Schmidt C, Wiedmann F, Voigt N, Zhou XB, Heijman J, Lang S, Albert V, Kallenberger S, Ruhparwar A, Szabó G, Kallenbach K, Karck M, Borggrefe M, Biliczki P, Ehrlich JR, Baczkó I, Lugenbiel P, Schweizer PA, Donner BC, Katus HA, Dobrev D, Thomas D. Upregulation of K(2P)3.1 K+ Current Causes Action Potential Shortening in Patients With Chronic Atrial Fibrillation. Circulation 2015; 132:82-92. [PMID: 25951834 DOI: 10.1161/circulationaha.114.012657] [Citation(s) in RCA: 156] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Accepted: 05/01/2015] [Indexed: 12/28/2022]
Abstract
BACKGROUND Antiarrhythmic management of atrial fibrillation (AF) remains a major clinical challenge. Mechanism-based approaches to AF therapy are sought to increase effectiveness and to provide individualized patient care. K(2P)3.1 (TASK-1 [tandem of P domains in a weak inward-rectifying K+ channel-related acid-sensitive K+ channel-1]) 2-pore-domain K+ (K(2P)) channels have been implicated in action potential regulation in animal models. However, their role in the pathophysiology and treatment of paroxysmal and chronic patients with AF is unknown. METHODS AND RESULTS Right and left atrial tissue was obtained from patients with paroxysmal or chronic AF and from control subjects in sinus rhythm. Ion channel expression was analyzed by quantitative real-time polymerase chain reaction and Western blot. Membrane currents and action potentials were recorded using voltage- and current-clamp techniques. K(2P)3.1 subunits exhibited predominantly atrial expression, and atrial K(2P)3.1 transcript levels were highest among functional K(2P) channels. K(2P)3.1 mRNA and protein levels were increased in chronic AF. Enhancement of corresponding currents in the right atrium resulted in shortened action potential duration at 90% of repolarization (APD90) compared with patients in sinus rhythm. In contrast, K(2P)3.1 expression was not significantly affected in subjects with paroxysmal AF. Pharmacological K(2P)3.1 inhibition prolonged APD90 in atrial myocytes from patients with chronic AF to values observed among control subjects in sinus rhythm. CONCLUSIONS Enhancement of atrium-selective K(2P)3.1 currents contributes to APD shortening in patients with chronic AF, and K(2P)3.1 channel inhibition reverses AF-related APD shortening. These results highlight the potential of K(2P)3.1 as a novel drug target for mechanism-based AF therapy.
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Affiliation(s)
- Constanze Schmidt
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Felix Wiedmann
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Niels Voigt
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Xiao-Bo Zhou
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Jordi Heijman
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Siegfried Lang
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Virginia Albert
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Stefan Kallenberger
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Arjang Ruhparwar
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Gábor Szabó
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Klaus Kallenbach
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Matthias Karck
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Martin Borggrefe
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Peter Biliczki
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Joachim R Ehrlich
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - István Baczkó
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Patrick Lugenbiel
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Patrick A Schweizer
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Birgit C Donner
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Hugo A Katus
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Dobromir Dobrev
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.)
| | - Dierk Thomas
- From Department of Cardiology, University of Heidelberg, Germany (C.S., F.W., V.A., P.L., P.A.S., H.A.K., D.T.); Division of Experimental Cardiology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany (N.V., X.-B.Z., J.H., S.L., M.B., D.D.); Institute of Pharmacology, Faculty of Medicine, University Duisburg-Essen, Essen, Germany (N.V., J.H., D.D.); First Department of Medicine, University Medical Center Mannheim, Germany (X.-B.Z., S.L., M.B.); Department for Bioinformatics and Functional Genomics, Division of Theoretical Bioinformatics, German Cancer Research Center, Institute for Pharmacy and Molecular Biotechnology and BioQuant, Heidelberg University, Germany (S.K.); Department of Cardiac Surgery, University Hospital Heidelberg, Germany (A.R., G.S., K.K., M.K.); Department of Cardiology, Internal Medicine III, Goethe University, Frankfurt, Germany (P.B., J.R.E.); Division of Cardiology, Deutsche Klinik für Diagnostik, Wiesbaden, Germany (P.B., J.R.E.); Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, University of Szeged, Hungary (I.B.); and Department of Cardiology, University of Basel Children's Hospital, Switzerland (B.C.D.).
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The role of acid-sensitive two-pore domain potassium channels in cardiac electrophysiology: focus on arrhythmias. Pflugers Arch 2014; 467:1055-67. [PMID: 25404566 DOI: 10.1007/s00424-014-1637-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 10/14/2014] [Accepted: 10/21/2014] [Indexed: 10/24/2022]
Abstract
The current kinetics of two-pore domain potassium (K2P) channels resemble those of the steady-state K(+) currents being active during the plateau phase of cardiac action potentials. Recent studies support that K2P channels contribute to these cardiac currents and thereby influence action potential duration in the heart. Ten of the 15 K2P channels present in the human genome are sensitive to variations of the extracellular and/or intracellular pH value. This review focuses on a set of K2P channels which are inhibited by extracellular protons, including the subgroup of tandem of P domains in a weak inward-rectifying K(+) (TWIK)-related acid-sensitive potassium (TASK) and TWIK-related alkaline-activated K(+) (TALK) channels. The role of TWIK-1 in the heart is also discussed since, after successful expression, an extracellular pH dependence, similar to that of TASK-1, was described as a hallmark of TWIK-1. The expression profile in cardiac tissue of different species and the functional data in the heart are summarized. The distinct role of the different acid-sensitive K2P channels in cardiac electrophysiology, inherited forms of arrhythmias and pharmacology, and their role as drug targets is currently emerging and is the subject of this review.
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Schmidt C, Wiedmann F, Langer C, Tristram F, Anand P, Wenzel W, Lugenbiel P, Schweizer PA, Katus HA, Thomas D. Cloning, functional characterization, and remodeling of K2P3.1 (TASK-1) potassium channels in a porcine model of atrial fibrillation and heart failure. Heart Rhythm 2014; 11:1798-805. [DOI: 10.1016/j.hrthm.2014.06.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Indexed: 01/17/2023]
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Inhibition of cardiac two-pore-domain K+ (K2P) channels – an emerging antiarrhythmic concept. Eur J Pharmacol 2014; 738:250-5. [DOI: 10.1016/j.ejphar.2014.05.056] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 05/28/2014] [Indexed: 12/13/2022]
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Kisselbach J, Seyler C, Schweizer PA, Gerstberger R, Becker R, Katus HA, Thomas D. Modulation of K2P 2.1 and K2P 10.1 K(+) channel sensitivity to carvedilol by alternative mRNA translation initiation. Br J Pharmacol 2014; 171:5182-94. [PMID: 25168769 DOI: 10.1111/bph.12596] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 12/20/2013] [Accepted: 01/16/2014] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND AND PURPOSE The β-receptor antagonist carvedilol blocks a range of ion channels. K2P 2.1 (TREK1) and K2P 10.1 (TREK2) channels are expressed in the heart and regulated by alternative translation initiation (ATI) of their mRNA, producing functionally distinct channel variants. The first objective was to investigate acute effects of carvedilol on human K2P 2.1 and K2P 10.1 channels. Second, we sought to study ATI-dependent modulation of K2P K(+) current sensitivity to carvedilol. EXPERIMENTAL APPROACH Using standard electrophysiological techniques, we recorded currents from wild-type and mutant K2P 2.1 and K2P 10.1 channels in Xenopus oocytes and HEK 293 cells. KEY RESULTS Carvedilol concentration-dependently inhibited K2P 2.1 channels (IC50 ,oocytes = 20.3 μM; IC50 , HEK = 1.6 μM) and this inhibition was frequency-independent. When K2P 2.1 isoforms generated by ATI were studied separately in oocytes, the IC50 value for carvedilol inhibition of full-length channels (16.5 μM) was almost 5-fold less than that for the truncated channel variant (IC50 = 79.0 μM). Similarly, the related K2P 10.1 channels were blocked by carvedilol (IC50 ,oocytes = 24.0 μM; IC50 , HEK = 7.6 μM) and subject to ATI-dependent modulation of drug sensitivity. CONCLUSIONS AND IMPLICATIONS Carvedilol targets K2P 2.1 and K2P 10.1 K(+) channels. This previously unrecognized mechanism supports a general role of cardiac K2P channels as antiarrhythmic drug targets. Furthermore, the work reveals that the sensitivity of the cardiac ion channels K2P 2.1 and K2P 10.1 to block was modulated by alternative mRNA translation initiation.
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Affiliation(s)
- J Kisselbach
- Department of Cardiology, Medical University Hospital, Heidelberg, Germany
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Seyler C, Schweizer PA, Zitron E, Katus HA, Thomas D. Vernakalant activates human cardiac K(2P)17.1 background K(+) channels. Biochem Biophys Res Commun 2014; 451:415-20. [PMID: 25108155 DOI: 10.1016/j.bbrc.2014.07.133] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 07/30/2014] [Indexed: 01/12/2023]
Abstract
Atrial fibrillation (AF) contributes significantly to cardiovascular morbidity and mortality. The growing epidemic is associated with cardiac repolarization abnormalities and requires the development of more effective antiarrhythmic strategies. Two-pore-domain K(+) channels stabilize the resting membrane potential and repolarize action potentials. Recently discovered K2P17.1 channels are expressed in human atrium and represent potential targets for AF therapy. However, cardiac electropharmacology of K2P17.1 channels remains to be investigated. This study was designed to elucidate human K2P17.1 regulation by antiarrhythmic drugs. Two-electrode voltage clamp and whole-cell patch clamp electrophysiology was used to record K2P currents from Xenopus oocytes and Chinese hamster ovary (CHO) cells. The class III antiarrhythmic compound vernakalant activated K2P17.1 currents in oocytes an in mammalian cells (EC50,CHO=40 μM) in frequency-dependent manner. K2P17.1 channel activation by vernakalant was specific among K2P channel family members. By contrast, vernakalant reduced K2P4.1 and K2P10.1 currents, in line with K2P2.1 blockade reported earlier. K2P17.1 open rectification characteristics and current-voltage relationships were not affected by vernakalant. The class I drug flecainide did not significantly modulate K2P currents. In conclusion, vernakalant activates K2P17.1 background potassium channels. Pharmacologic K2P channel activation by cardiovascular drugs has not been reported previously and may be employed for personalized rhythm control in patients with AF-associated reduction of K(+) channel function.
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Affiliation(s)
- Claudia Seyler
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Patrick A Schweizer
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Edgar Zitron
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany.
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Schmitt N, Grunnet M, Olesen SP. Cardiac potassium channel subtypes: new roles in repolarization and arrhythmia. Physiol Rev 2014; 94:609-53. [PMID: 24692356 DOI: 10.1152/physrev.00022.2013] [Citation(s) in RCA: 174] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K+ channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K+ channels drive the late repolarization of the ventricle with some redundancy, and in atria this repolarization reserve is supplemented by the fairly atrial-specific KV1.5, Kir3, KCa, and K2P channels. The role of the latter two subtypes in atria is currently being clarified, and several findings indicate that they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K+ channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occurs in disease states such as atrial fibrillation or heart failure. The underlying posttranscriptional and posttranslational remodeling of the individual K+ channels changes their activity and significance relative to each other, and they must be viewed together to understand their role in keeping a stable heart rhythm, also under menacing conditions like attacks of reentry arrhythmia.
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31
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Liang B, Soka M, Christensen AH, Olesen MS, Larsen AP, Knop FK, Wang F, Nielsen JB, Andersen MN, Humphreys D, Mann SA, Huttner IG, Vandenberg JI, Svendsen JH, Haunsø S, Preiss T, Seebohm G, Olesen SP, Schmitt N, Fatkin D. Genetic variation in the two-pore domain potassium channel, TASK-1, may contribute to an atrial substrate for arrhythmogenesis. J Mol Cell Cardiol 2013; 67:69-76. [PMID: 24374141 DOI: 10.1016/j.yjmcc.2013.12.014] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 12/09/2013] [Accepted: 12/17/2013] [Indexed: 12/22/2022]
Abstract
The two-pore domain potassium channel, K2P3.1 (TASK-1) modulates background conductance in isolated human atrial cardiomyocytes and has been proposed as a potential drug target for atrial fibrillation (AF). TASK-1 knockout mice have a predominantly ventricular phenotype however, and effects of TASK-1 inactivation on atrial structure and function have yet to be demonstrated in vivo. The extent to which genetic variation in KCNK3, that encodes TASK-1, might be a determinant of susceptibility to AF is also unknown. To address these questions, we first evaluated the effects of transient knockdown of the zebrafish kcnk3a and kcnk3b genes and cardiac phenotypes were evaluated using videomicroscopy. Combined kcnk3a and kcnk3b knockdown in 72 hour post fertilization embryos resulted in lower heart rate (p<0.001), marked increase in atrial diameter (p<0.001), and mild increase in end-diastolic ventricular diameter (p=0.01) when compared with control-injected embryos. We next performed genetic screening of KCNK3 in two independent AF cohorts (373 subjects) and identified three novel KCNK3 variants. Two of these variants, present in one proband with familial AF, were located at adjacent nucleotides in the Kozak sequence and reduced expression of an engineered reporter. A third missense variant, V123L, in a patient with lone AF, reduced resting membrane potential and altered pH sensitivity in patch-clamp experiments, with structural modeling predicting instability in the vicinity of the TASK-1 pore. These in vitro data suggest that the double Kozak variants and V123L will have loss-of-function effects on ITASK. Cardiac action potential modeling predicted that reduced ITASK prolongs atrial action potential duration, and that this is potentiated by reciprocal changes in activity of other ion channel currents. Our findings demonstrate the functional importance of ITASK in the atrium and suggest that inactivation of TASK-1 may have diverse effects on atrial size and electrophysiological properties that can contribute to an arrhythmogenic substrate.
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Affiliation(s)
- Bo Liang
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Magdalena Soka
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Alex Horby Christensen
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Morten S Olesen
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Anders P Larsen
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark; Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - Filip K Knop
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Fan Wang
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Jonas B Nielsen
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Martin N Andersen
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - David Humphreys
- Molecular Genetics Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Stefan A Mann
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Inken G Huttner
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
| | - Jamie I Vandenberg
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia; Faculty of Medicine, University of New South Wales, Kensington, New South Wales, Australia
| | - Jesper H Svendsen
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Stig Haunsø
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Preiss
- John Curtin School of Medical Research, Australian National University, Canberra, Australian Capital Territory, Australia
| | - Guiscard Seebohm
- Institute for Genetics of Heart Diseases (IfGH), Department of Cardiovascular Medicine, University Hospital Münster, Germany
| | - Søren-Peter Olesen
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark
| | - Nicole Schmitt
- Danish National Research Foundation Centre for Cardiac Arrhythmia, University of Copenhagen, Copenhagen, Denmark.
| | - Diane Fatkin
- Molecular Cardiology Division, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia; Faculty of Medicine, University of New South Wales, Kensington, New South Wales, Australia; Cardiology Department, St Vincent's Hospital, Darlinghurst, New South Wales, Australia
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Seyler C, Li J, Schweizer PA, Katus HA, Thomas D. Inhibition of cardiac two-pore-domain K+ (K2P) channels by the antiarrhythmic drug vernakalant--comparison with flecainide. Eur J Pharmacol 2013; 724:51-7. [PMID: 24374008 DOI: 10.1016/j.ejphar.2013.12.030] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2013] [Revised: 12/16/2013] [Accepted: 12/18/2013] [Indexed: 01/25/2023]
Abstract
The mixed ion channel blocker, vernakalant (RSD1235), is effective in rapid conversion of atrial fibrillation (AF) to sinus rhythm (SR). Suppression of cardiac two-pore-domain potassium (K2P) channels causes action potential prolongation and has recently been proposed as a novel antiarrhythmic strategy. The objective of this study was to investigate acute effects of vernakalant on human K2P2.1 (TREK-1) and K2P3.1 (TASK-1) channels to provide a more complete picture of its antiarrhythmic mechanism of action. The class IC antiarrhythmic drug flecainide was studied as a comparator agent. Two-electrode voltage clamp and whole-cell patch clamp electrophysiology was used to record K2P currents from Xenopus oocytes and Chinese hamster ovary (CHO) cells. Vernakalant inhibited cardiac K2P2.1 channels expressed in Xenopus oocytes and in CHO cells. The IC50 value obtained from mammalian cells (13.3 µM) was close to the range of vernakalant levels reported in patients (2-8 µM), indicating potential clinical significance of K2P2.1 blockade. Open rectification characteristics and current-voltage relationships of K2P2.1 currents were not affected by vernakalant. Vernakalant did not significantly reduce K2P3.1 currents. Finally, the class I antiarrhythmic drug flecainide had no effect on K2P2.1 or K2P3.1 channels. In conclusion, the recently developed antiarrhythmic drug vernakalant targets human K2P2.1 K(+) background channels. This previously unrecognized inhibitory property adds to the multichannel blocking profile of vernakalant and extends the mechanistic basis for its anti-fibrillatory effect.
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Affiliation(s)
- Claudia Seyler
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Jin Li
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Patrick A Schweizer
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital, Heidelberg, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany.
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Schmidt C, Wiedmann F, Tristram F, Anand P, Wenzel W, Lugenbiel P, Schweizer PA, Katus HA, Thomas D. Cardiac expression and atrial fibrillation-associated remodeling of K₂p2.1 (TREK-1) K⁺ channels in a porcine model. Life Sci 2013; 97:107-15. [PMID: 24345461 DOI: 10.1016/j.lfs.2013.12.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 11/19/2013] [Accepted: 12/05/2013] [Indexed: 01/01/2023]
Abstract
AIMS Effective management of atrial fibrillation (AF) often remains an unmet need. Cardiac two-pore-domain K(+) (K2P) channels are implicated in action potential regulation, and their inhibition has been proposed as a novel antiarrhythmic strategy. K2P2.1 (TREK-1) channels are expressed in the human heart. This study was designed to identify and functionally express porcine K2P2.1 channels. In addition, we sought to analyze cardiac expression and AF-associated K2P2.1 remodeling in a clinically relevant porcine AF model. MAIN METHODS Three pK2P2.1 isoforms were identified and amplified. Currents were recorded using voltage clamp electrophysiology in the Xenopus oocyte expression system. K2P2.1 remodeling was studied by quantitative real time PCR and Western blot in domestic pigs during AF induced by atrial burst pacing. KEY FINDINGS Human and porcine K2P2.1 proteins share 99% identity. Residues involved in phosphorylation or glycosylation are conserved. Porcine K2P2.1 channels carried outwardly rectifying K(+) currents similar to their human counterparts. In pigs, K2P2.1 was expressed ubiquitously in the heart with predominance in the atrial tissue. AF was associated with time-dependent reduction of K2P2.1 protein in the RA by 70% (7 days of AF) and 80% (21 days of AF) compared to control animals in sinus rhythm. K2P2.1 expression in the left atrium, AV node, and ventricles was not affected by AF. SIGNIFICANCE Similarities between porcine and human K2P2.1 channels indicate that the pig may represent a valid model for mechanistic and preclinical studies. AF-related atrial K2P2.1 remodeling has potential implications for arrhythmia maintenance and antiarrhythmic therapy.
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Affiliation(s)
- Constanze Schmidt
- Department of Cardiology, Medical University Hospital, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Felix Wiedmann
- Department of Cardiology, Medical University Hospital, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Frank Tristram
- Institute of Nanotechnology, Karlsruhe Institute of Technology, P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Priya Anand
- Institute of Nanotechnology, Karlsruhe Institute of Technology, P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Wolfgang Wenzel
- Institute of Nanotechnology, Karlsruhe Institute of Technology, P.O. Box 3640, D-76021 Karlsruhe, Germany
| | - Patrick Lugenbiel
- Department of Cardiology, Medical University Hospital, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Patrick A Schweizer
- Department of Cardiology, Medical University Hospital, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, Medical University Hospital, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany
| | - Dierk Thomas
- Department of Cardiology, Medical University Hospital, Im Neuenheimer Feld 410, D-69120 Heidelberg, Germany.
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Functional characterization of zebrafish K2P18.1 (TRESK) two-pore-domain K+ channels. Naunyn Schmiedebergs Arch Pharmacol 2013; 387:291-300. [DOI: 10.1007/s00210-013-0945-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Accepted: 11/22/2013] [Indexed: 01/25/2023]
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Class I antiarrhythmic drugs inhibit human cardiac two-pore-domain K+ (K2P) channels. Eur J Pharmacol 2013; 721:237-48. [DOI: 10.1016/j.ejphar.2013.09.029] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 09/04/2013] [Accepted: 09/11/2013] [Indexed: 11/22/2022]
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36
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Salem KA, Qureshi MA, Sydorenko V, Parekh K, Jayaprakash P, Iqbal T, Singh J, Oz M, Adrian TE, Howarth FC. Effects of exercise training on excitation-contraction coupling and related mRNA expression in hearts of Goto-Kakizaki type 2 diabetic rats. Mol Cell Biochem 2013; 380:83-96. [PMID: 23620341 DOI: 10.1007/s11010-013-1662-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/17/2013] [Indexed: 10/26/2022]
Abstract
Although, several novel forms of intervention aiming at newly identified therapeutic targets are currently being developed for diabetes mellitus (DM), it is well established that physical exercise continues to be one of the most valuable forms of non-pharmacological therapy. The aim of the study was to investigate the effects of exercise training on excitation-contraction coupling and related gene expression in the Goto-Kakizaki (GK) type 2 diabetic rat heart and whether exercise is able to reverse diabetes-induced changes in excitation-contraction coupling and gene expression. Experiments were performed in GK and control rats aged 10-11 months following 2-3 months of treadmill exercise training. Shortening, [Ca(2+)]i and L-type Ca(2+) current were measured in ventricular myocytes with video edge detection, fluorescence photometry and whole cell patch clamp techniques, respectively. Expression of mRNA was assessed in ventricular muscle with real-time RT-PCR. Amplitude of shortening, Ca(2+) transients and L-type Ca(2+) current were not significantly altered in ventricular myocytes from GK sedentary compared to control sedentary rats or by exercise training. Expression of mRNA encoding Tpm2, Gja4, Atp1b1, Cacna1g, Cacnb2, Hcn2, Kcna3 and Kcne1 were up-regulated and Gja1, Kcnj2 and Kcnk3 were down-regulated in hearts of sedentary GK rats compared to sedentary controls. Gja1, Cav3 and Kcnk3 were up-regulated and Hcn2 was down-regulated in hearts of exercise trained GK compared to sedentary GK controls. Ventricular myocyte shortening and Ca(2+) transport were generally well preserved despite alterations in the profile of expression of mRNA encoding a variety of cardiac muscle proteins in the adult exercise trained GK diabetic rat heart.
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Affiliation(s)
- K A Salem
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, UAE
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Heijman J, Voigt N, Dobrev D. New directions in antiarrhythmic drug therapy for atrial fibrillation. Future Cardiol 2013; 9:71-88. [DOI: 10.2217/fca.12.78] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia and has a significant impact on morbidity and mortality. Current antiarrhythmic drugs for AF suffer from limited safety and efficacy, probably because they were not designed based on specific pathological mechanisms. Recent research has provided important insights into the mechanisms contributing to AF and highlighted several potential novel antiarrhythmic strategies. In this review, we highlight the main pathological mechanisms of AF, discuss traditional and novel aspects of atrial antiarrhythmic drugs in relation to these pathological mechanisms, and present potential novel therapeutic approaches including structure-based modulation of atrial-specific cardiac ion channels, restoring abnormal Ca2+ handling in AF and targeting atrial remodeling.
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Affiliation(s)
- Jordi Heijman
- Institute of Pharmacology, Medical Faculty Essen, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
| | - Niels Voigt
- Institute of Pharmacology, Medical Faculty Essen, University of Duisburg-Essen, Hufelandstrasse 55, 45122 Essen, Germany
- Division of Experimental Cardiology, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
| | - Dobromir Dobrev
- DZHK (German Centre for Cardiovascular Research), Partner Site Heidelberg/Mannheim, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany
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Kisselbach J, Schweizer PA, Gerstberger R, Becker R, Katus HA, Thomas D. Enhancement of K2P2.1 (TREK1) background currents expressed in Xenopus oocytes by voltage-gated K+ channel β subunits. Life Sci 2012; 91:377-383. [DOI: 10.1016/j.lfs.2012.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 07/17/2012] [Accepted: 08/02/2012] [Indexed: 11/26/2022]
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Rahm AK, Gierten J, Kisselbach J, Staudacher I, Staudacher K, Schweizer PA, Becker R, Katus HA, Thomas D. PKC-dependent activation of human K(2P) 18.1 K(+) channels. Br J Pharmacol 2012; 166:764-73. [PMID: 22168364 DOI: 10.1111/j.1476-5381.2011.01813.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Two-pore-domain K(+) channels (K(2P) ) mediate K(+) background currents that modulate the membrane potential of excitable cells. K(2P) 18.1 (TWIK-related spinal cord K(+) channel) provides hyperpolarizing background currents in neurons. Recently, a dominant-negative loss-of-function mutation in K(2P) 18.1 has been implicated in migraine, and activation of K(2P) 18.1 channels was proposed as a therapeutic strategy. Here we elucidated the molecular mechanisms underlying PKC-dependent activation of K(2P) 18.1 currents. EXPERIMENTAL APPROACH Human K(2P) 18.1 channels were heterologously expressed in Xenopus laevis oocytes, and currents were recorded with the two-electrode voltage clamp technique. KEY RESULTS Stimulation of PKC using phorbol 12-myristate-13-acetate (PMA) activated the hK(2P) 18.1 current by 3.1-fold in a concentration-dependent fashion. The inactive analogue 4α-PMA had no effect on channel activity. The specific PKC inhibitors bisindolylmaleimide I, Ro-32-0432 and chelerythrine reduced PMA-induced channel activation indicating that PKC is involved in this effect of PMA. Selective activation of conventional PKC isoforms with thymeleatoxin (100 nM) did not reproduce K(2P) 18.1 channel activation. Current activation by PMA was not affected by pretreatment with CsA (calcineurin inhibitor) or KT 5720 (PKA inhibitor), ruling out a significant contribution of calcineurin or cross-talk with PKA to the PKC-dependent hK(2P) 18.1 activation. Finally, mutation of putative PKC phosphorylation sites did not prevent PMA-induced K(2P) 18.1 channel activation. CONCLUSIONS AND IMPLICATIONS We demonstrated that activation of hK(2P) 18.1 (TRESK) by PMA is mediated by PKC stimulation. Hence, PKC-mediated activation of K(2P) 18.1 background currents may serve as a novel molecular target for migraine treatment.
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Affiliation(s)
- Ann-Kathrin Rahm
- Department of Cardiology, Medical University Hospital Heidelberg, Heidelberg, Germany
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Novel electrophysiological properties of dronedarone: inhibition of human cardiac two-pore-domain potassium (K2P) channels. Naunyn Schmiedebergs Arch Pharmacol 2012; 385:1003-16. [DOI: 10.1007/s00210-012-0780-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 06/29/2012] [Indexed: 12/27/2022]
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Gierten J, Hassel D, Schweizer PA, Becker R, Katus HA, Thomas D. Identification and functional characterization of zebrafish K2P10.1 (TREK2) two-pore-domain K+ channels. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:33-41. [DOI: 10.1016/j.bbamem.2011.09.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 09/09/2011] [Accepted: 09/13/2011] [Indexed: 10/17/2022]
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Staudacher K, Staudacher I, Ficker E, Seyler C, Gierten J, Kisselbach J, Rahm AK, Trappe K, Schweizer PA, Becker R, Katus HA, Thomas D. Carvedilol targets human K2P 3.1 (TASK1) K+ leak channels. Br J Pharmacol 2011; 163:1099-110. [PMID: 21410455 PMCID: PMC3130955 DOI: 10.1111/j.1476-5381.2011.01319.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2010] [Revised: 01/20/2011] [Accepted: 02/05/2011] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND PURPOSE Human K(2P) 3.1 (TASK1) channels represent potential targets for pharmacological management of atrial fibrillation. K(2P) channels control excitability by stabilizing membrane potential and by expediting repolarization. In the heart, inhibition of K(2P) currents by class III antiarrhythmic drugs results in action potential prolongation and suppression of electrical automaticity. Carvedilol exerts antiarrhythmic activity and suppresses atrial fibrillation following cardiac surgery or cardioversion. The objective of this study was to investigate acute effects of carvedilol on human K(2P) 3.1 (hK(2P) 3.1) channels. EXPERIMENTAL APPROACH Two-electrode voltage clamp and whole-cell patch clamp electrophysiology was used to record hK(2P) 3.1 currents from Xenopus oocytes, Chinese hamster ovary (CHO) cells and human pulmonary artery smooth muscle cells (hPASMC). KEY RESULTS Carvedilol concentration-dependently inhibited hK(2P) 3.1 currents in Xenopus oocytes (IC(50) = 3.8 µM) and in mammalian CHO cells (IC(50) = 0.83 µM). In addition, carvedilol sensitivity of native I(K2P3.1) was demonstrated in hPASMC. Channels were blocked in open and closed states in frequency-dependent fashion, resulting in resting membrane potential depolarization by 7.7 mV. Carvedilol shifted the current-voltage (I-V) relationship by -6.9 mV towards hyperpolarized potentials. Open rectification, characteristic of K(2P) currents, was not affected. CONCLUSIONS AND IMPLICATIONS The antiarrhythmic drug carvedilol targets hK(2P) 3.1 background channels. We propose that cardiac hK(2P) 3.1 current blockade may suppress electrical automaticity, prolong atrial refractoriness and contribute to the class III antiarrhythmic action in patients treated with the drug.
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Affiliation(s)
- K Staudacher
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - I Staudacher
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - E Ficker
- Rammelkamp Center, MetroHealth Campus, Case Western Reserve UniversityCleveland, OH, USA
| | - C Seyler
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - J Gierten
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - J Kisselbach
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - A-K Rahm
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - K Trappe
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - PA Schweizer
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - R Becker
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - HA Katus
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
| | - D Thomas
- Department of Cardiology, Medical University Hospital HeidelbergHeidelberg, Germany
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Ehrlich JR, Dobrev D. Atrial-selective sodium channel block by dronedarone: sufficient to terminate atrial fibrillation? Naunyn Schmiedebergs Arch Pharmacol 2011; 384:109-14. [DOI: 10.1007/s00210-011-0647-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2011] [Accepted: 02/23/2011] [Indexed: 11/27/2022]
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Schmidt C, Kisselbach J, Schweizer PA, Katus HA, Thomas D. The pathology and treatment of cardiac arrhythmias: focus on atrial fibrillation. Vasc Health Risk Manag 2011; 7:193-202. [PMID: 21490945 PMCID: PMC3072743 DOI: 10.2147/vhrm.s10758] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Indexed: 01/10/2023] Open
Abstract
Atrial fibrillation (AF) is the most frequently encountered sustained cardiac arrhythmia in clinical practice and a major cause of morbidity and mortality. Effective treatment of AF still remains an unmet medical need. Treatment of AF is based on drug therapy and ablative strategies. Antiarrhythmic drug therapy is limited by a relatively high recurrence rate and proarrhythmic side effects. Catheter ablation suppresses paroxysmal AF in the majority of patients without structural heart disease but is more difficult to achieve in patients with persistent AF or with concomitant cardiac disease. Stroke is a potentially devastating complication of AF, requiring anticoagulation that harbors the risk of bleeding. In search of novel treatment modalities, targeted pharmacological treatment and gene therapy offer the potential for greater selectivity than conventional small-molecule or interventional approaches. This paper summarizes the current understanding of molecular mechanisms underlying AF. Established drug therapy and interventional treatment of AF is reviewed, and emerging clinical and experimental therapeutic approaches are highlighted.
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Affiliation(s)
- Constanze Schmidt
- Department of Cardiology, Medical University Hospital, Heidelberg, Germany
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Ravens U. Antiarrhythmic therapy in atrial fibrillation. Pharmacol Ther 2010; 128:129-45. [DOI: 10.1016/j.pharmthera.2010.06.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Accepted: 06/11/2010] [Indexed: 12/19/2022]
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46
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Novel pharmacological approaches for antiarrhythmic therapy. Naunyn Schmiedebergs Arch Pharmacol 2010; 381:187-93. [DOI: 10.1007/s00210-009-0487-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 12/17/2009] [Indexed: 01/14/2023]
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