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Pluteanu F, Glaser D, Massing F, Schulte JS, Kirchhefer U. Loss of protein phosphatase 2A regulatory subunit PPP2R5A is associated with increased incidence of stress-induced proarrhythmia. Front Cardiovasc Med 2024; 11:1419597. [PMID: 38863902 PMCID: PMC11165201 DOI: 10.3389/fcvm.2024.1419597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Accepted: 05/16/2024] [Indexed: 06/13/2024] Open
Abstract
Background Protein phosphatase 2A (PP2A) is a serine/threonine-selective holoenzyme that controls Ca2+ homeostasis and contractility of the heart via dephosphorylation of regulatory proteins. In some genetically modified mouse models with increased arrhythmogenicity, a reduced expression of the regulatory subunit B56α of PP2A was found as a concomitant effect. Whether there is a general correlation between the abundance of B56α and the promotion of cardiac arrhythmogenesis remains unclear. Methods The aim of this study was therefore to investigate the role of PP2A-B56α in the propensity for arrhythmic activity in the heart. The experimental analysis of this question has been addressed by using a mouse model with deletion of the PP2A-B56α gene, PPP2R5A (KO), in comparison to wild-type animals (WT). Evidence for arrhythmogenicity was investigated in whole animal, isolated heart and cardiomyocytes by ECG, recording of monophasic action potential (MAP) induced by programmed electrical stimulation (PES), measurement of Ca2+ transients under increased pacing frequencies and determination of total K+ channel currents (I K). Results ECG measurements showed a prolongation of QT time in KO vs. WT. KO mice exhibited a higher rate of premature ventricular contractions in the ECG. MAP measurements in Langendorff-perfused KO hearts showed increased episodes of ventricular tachyarrhythmia induced by PES. However, the KO hearts showed values for MAP duration that were similar to those in WT hearts. In contrast, KO showed more myocardial cells with spontaneous arrhythmogenic Ca2+ transient events compared to WT. The whole-cell patch-clamp technique applied to ventricular cardiomyocytes revealed comparable peak potassium channel current densities between KO and WT. Conclusion These findings support the assumption that a decrease or even the loss of PP2A-B56α leads to an increased propensity of triggered arrhythmias. This could be based on the increased spontaneous Ca2+ tansients observed.
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Affiliation(s)
- Florentina Pluteanu
- Department of Anatomy, Animal Physiology and Biophysics, University of Bucharest, Bucharest, Romania
| | - Dennis Glaser
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Fabian Massing
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Jan S. Schulte
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Universitätsklinikum Münster, Universität Münster, Münster, Germany
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2
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Zeng Q, Li W, Luo Z, Zhou H, Duan Z, Xiong XL. The role of miR1 and miR133a in new-onset atrial fibrillation after acute myocardial infarction. BMC Cardiovasc Disord 2023; 23:448. [PMID: 37697243 PMCID: PMC10496401 DOI: 10.1186/s12872-023-03462-x] [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: 04/12/2023] [Accepted: 08/19/2023] [Indexed: 09/13/2023] Open
Abstract
BACKGROUND The development of new-onset atrial fibrillation (NOAF) after acute myocardial infarction (AMI) is a clinical complication that requires a better understanding of the causative risk factors. This study aimed to explore the risk factors and the expression and function of miR-1 and miR-133a in new atrial fibrillation after AMI. METHODS We collected clinical data from 172 patients with AMI treated with emergency percutaneous coronary intervention (PCI) between October 2021 and October 2022. Independent predictors of NOAF were determined using binary logistic univariate and multivariate regression analyses. The predictive value of NOAF was assessed using the area under the receiver operating characteristic (ROC) curve for related risk factors. In total, 172 venous blood samples were collected preoperatively and on the first day postoperatively; the expression levels of miR-1 and miR-133a were determined using the polymerase chain reaction. The clinical significance of miR-1 and miR-133a expression levels was determined by Spearman correlation analysis. RESULTS The Glasgow prognostic score, left atrial diameter, and infarct area were significant independent risk factors for NOAF after AMI. We observed that the expression levels of miR-1 and miR-133a were significantly higher in the NOAF group than in the non-NOAF group. On postoperative day 1, strong associations were found between miR-133a expression levels and the neutrophil ratio and between miR-1 expression levels and an increased left atrial diameter. CONCLUSIONS Our findings indicate that the mechanism of NOAF after AMI may include an inflammatory response associated with an increased miR-1-related mechanism. Conversely, miR-133a could play a protective role in this clinical condition.
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Affiliation(s)
- Qingyi Zeng
- Guizhou Medical University, 9 Beijing Road, Guiyang, 550000, Guizhou, China
- The Second Affiliated Hospital of Guizhou University of Chinese Medicine, 83 Feishan Street, Guiyang, China
| | - Wei Li
- Guizhou Medical University, 9 Beijing Road, Guiyang, 550000, Guizhou, China.
- Affiliated Hospital of Guizhou Medical University, 16 Beijing Road, Guiyang, 550000, Guizhou, China.
| | - Zhenghua Luo
- Guizhou Provincial People's Hospital, 83 Zhongshan East Road, Guiyang, 55000, Guizhou, China
| | - Haiyan Zhou
- Guizhou Medical University, 9 Beijing Road, Guiyang, 550000, Guizhou, China
- Affiliated Hospital of Guizhou Medical University, 16 Beijing Road, Guiyang, 550000, Guizhou, China
| | - Zhonggang Duan
- Guizhou Medical University, 9 Beijing Road, Guiyang, 550000, Guizhou, China
- Affiliated Hospital of Guizhou Medical University, 16 Beijing Road, Guiyang, 550000, Guizhou, China
| | - Xin Lin Xiong
- Guizhou Medical University, 9 Beijing Road, Guiyang, 550000, Guizhou, China
- Affiliated Hospital of Guizhou Medical University, 16 Beijing Road, Guiyang, 550000, Guizhou, China
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3
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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: 0] [Impact Index Per Article: 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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4
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Wang Z, Zhao X, Bu L, Liu K, Li Z, Zhang H, Zhang X, Yuan F, Wang S, Guo Z, Shi L. Low sodium intake ameliorates hypertension and left ventricular hypertrophy in mice with primary aldosteronism. Front Physiol 2023; 14:1136574. [PMID: 36875038 PMCID: PMC9974669 DOI: 10.3389/fphys.2023.1136574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/01/2023] [Indexed: 02/17/2023] Open
Abstract
The goal of this paper is to elucidate the effects of sodium restriction on hypertension and left ventricular (LV) hypertrophy in a mouse model with primary aldosteronism (PA). Mice with genetic deletion of TWIK-related acid-sensitive K (TASK)-1 and TASK-3 channels (TASK-/-) were used as the animal model of PA. Parameters of the LV were assessed using echocardiography and histomorphology analysis. Untargeted metabolomics analysis was conducted to reveal the mechanisms underlying the hypertrophic changes in the TASK-/- mice. The TASK-/- adult male mice exhibited the hallmarks of PA, including hypertension, hyperaldosteronism, hypernatremia, hypokalemia, and mild acid-base balance disorders. Two weeks of low sodium intake significantly reduced the 24-h average systolic and diastolic BP in TASK-/- but not TASK+/+ mice. In addition, TASK-/- mice showed increasing LV hypertrophy with age, and 2 weeks of the low-sodium diet significantly reversed the increased BP and LV wall thickness in adult TASK-/- mice. Furthermore, a low-sodium diet beginning at 4 weeks of age protected TASK-/- mice from LV hypertrophy at 8-12 weeks of age. Untargeted metabolomics demonstrated that the disturbances in heart metabolism in the TASK-/- mice (e.g., Glutathione metabolism; biosynthesis of unsaturated fatty acids; amino sugar and nucleotide sugar metabolism; pantothenate and CoA biosynthesis; D-glutamine and D-glutamate metabolism), some of which were reversed after sodium restriction, might be involved in the development of LV hypertrophy. In conclusion, adult male TASK-/- mice exhibit spontaneous hypertension and LV hypertrophy, which are ameliorated by a low-sodium intake.
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Affiliation(s)
- Zitian Wang
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Xue Zhao
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Lifang Bu
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Kun Liu
- Department of Laboratory Medicine, Hebei University of Chinese Medicine, Shijiazhuang, China
| | - Ziping Li
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Huaxing Zhang
- Core Facilities and Centers, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Xiaoguang Zhang
- Core Facilities and Centers, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Fang Yuan
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China.,Hebei Key Laboratory of Neurophysiology, Shijiazhuang, Hebei, China
| | - Sheng Wang
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China.,Hebei Key Laboratory of Neurophysiology, Shijiazhuang, Hebei, China
| | - Zan Guo
- Core Facilities and Centers, Institute of Medicine and Health, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Luo Shi
- Department of Neurobiology, Hebei Medical University, Shijiazhuang, Hebei, China.,Hebei Key Laboratory of Neurophysiology, Shijiazhuang, Hebei, China
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5
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Wiedmann F, Kraft M, Kallenberger S, Büscher A, Paasche A, Blochberger PL, Seeger T, Jávorszky N, Warnecke G, Arif R, Kremer J, Karck M, Frey N, Schmidt C. MicroRNAs Regulate TASK-1 and Are Linked to Myocardial Dilatation in Atrial Fibrillation. J Am Heart Assoc 2022; 11:e023472. [PMID: 35301863 PMCID: PMC9075420 DOI: 10.1161/jaha.121.023472] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Background Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia. However, underlying molecular mechanisms are insufficiently understood. Previous studies suggested that microRNA (miRNA) dependent gene regulation plays an important role in the initiation and maintenance of AF. The 2‐pore‐domain potassium channel TASK‐1 (tandem of P domains in a weak inward rectifying K+ channel–related acid sensitive K+ channel 1) is an atrial‐specific ion channel that is upregulated in AF. Inhibition of TASK‐1 current prolongs the atrial action potential duration to similar levels as in patients with sinus rhythm. Here, we hypothesize that miRNAs might be responsible for the regulation of KCNK3 that encodes for TASK‐1. Methods and Results We selected miRNAs potentially regulating KCNK3 and studied their expression in atrial tissue samples obtained from patients with sinus rhythm, paroxysmal AF, or permanent/chronic AF. MiRNAs differentially expressed in AF were further investigated for their ability to regulate KCNK3 mRNA and TASK‐1 protein expression in human induced pluripotent stem cells, transfected with miRNA mimics or inhibitors. Thereby, we observed that miR‐34a increases TASK‐1 expression and current and further decreases the resting membrane potential of Xenopus laevis oocytes, heterologously expressing hTASK‐1. Finally, we investigated associations between miRNA expression in atrial tissues and clinical parameters of our patient cohort. A cluster containing AF stage, left ventricular end‐diastolic diameter, left ventricular end‐systolic diameter, left atrial diameter, atrial COL1A2 (collagen alpha‐2(I) chain), and TASK‐1 protein level was associated with increased expression of miR‐25, miR‐21, miR‐34a, miR‐23a, miR‐124, miR‐1, and miR‐29b as well as decreased expression of miR‐9 and miR‐485. Conclusions These results suggest an important pathophysiological involvement of miRNAs in the regulation of atrial expression of the TASK‐1 potassium channel in patients with atrial cardiomyopathy.
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Affiliation(s)
- Felix Wiedmann
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,DZHK (German Center for Cardiovascular Research) Partner Site Heidelberg/Mannheim University of Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
| | - Manuel Kraft
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,DZHK (German Center for Cardiovascular Research) Partner Site Heidelberg/Mannheim University of Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
| | - Stefan Kallenberger
- Digital Health Center Berlin Institute of Health (BIH) and Charité Berlin Germany.,Department of Medical Oncology National Center for Tumor DiseasesHeidelberg University Hospital Heidelberg Germany.,Health Data Science UnitMedical Faculty Heidelberg Heidelberg Germany
| | - Antonius Büscher
- Department for Cardiology II: Electrophysiology University Hospital Münster Münster Germany
| | - Amelie Paasche
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
| | - Pablo L Blochberger
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,DZHK (German Center for Cardiovascular Research) Partner Site Heidelberg/Mannheim University of Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
| | - Timon Seeger
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany
| | - Natasa Jávorszky
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
| | - Gregor Warnecke
- Department of Cardiac Surgery University of Heidelberg Germany
| | - Rawa Arif
- Department of Cardiac Surgery University of Heidelberg Germany
| | - Jamila Kremer
- Department of Cardiac Surgery University of Heidelberg Germany
| | - Matthias Karck
- Department of Cardiac Surgery University of Heidelberg Germany
| | - Norbert Frey
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,DZHK (German Center for Cardiovascular Research) Partner Site Heidelberg/Mannheim University of Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
| | - Constanze Schmidt
- Department of Cardiology Heidelberg University Hospital Heidelberg Germany.,DZHK (German Center for Cardiovascular Research) Partner Site Heidelberg/Mannheim University of Heidelberg Germany.,HCR Heidelberg Center for Heart Rhythm Disorders Heidelberg University Hospital Heidelberg Germany
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6
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TASK-1 regulates mitochondrial function under hypoxia. Biochem Biophys Res Commun 2021; 578:163-169. [PMID: 34571371 DOI: 10.1016/j.bbrc.2021.09.032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 09/16/2021] [Indexed: 11/23/2022]
Abstract
TASK-1, TWIK-related acid-sensitive potassium channel 1, is a member of the two-pore- domain potassium channel family. It is constitutively active at resting potentials and strongly expressed in the heart. However, little is known about the role of TASK-1 channels in hypoxia. A cellular model of hypoxia and reoxygenation from rat heart-derived H9c2 cells or TASK-1 deficient HEK293T cells was employed to explore the role of TASK-1 channels in cytoprotection against hypoxia. The cell viability assay revealed that TASK-1 expression increased the number of viable cells subjected to 2 h of hypoxia followed by 2 h of reoxygenation (H/R). To dissect the protective role of TASK-1 on mitochondrial function, mitochondrial membrane potential (MMP) was assessed by tetramethylrhodamine fluorescence. It was demonstrated that MMP was significantly decreased by H/R, but it was maintained by TASK-1 expression or pretreatment with cyclosporin A, an inhibitor of mitochondrial permeability transition pore (mPTP). The effect of cyclosporin A on MMP was not further altered by TASK-1 expression. Moreover, TASK-1 expression significantly blocked cytochrome c release induced by H/R. While a small fraction of endogenous TASK-1 was found to colocalize with the mitochondrial marker MitoTracker in H9c2 cells, H/R did not alter the extent of colocalization of TASK-1 with MitoTracker. The total TASK-1 protein level was not significantly affected by H/R. In summary, we provided the evidence that TASK-1 channels confer cytoprotection against hypoxia-reoxygenation injury, possibly by their capacity of maintaining the mitochondrial membrane potential via inhibiting MPTP opening.
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7
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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: 14] [Impact Index Per Article: 4.7] [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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8
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Turner D, Kang C, Mesirca P, Hong J, Mangoni ME, Glukhov AV, Sah R. Electrophysiological and Molecular Mechanisms of Sinoatrial Node Mechanosensitivity. Front Cardiovasc Med 2021; 8:662410. [PMID: 34434970 PMCID: PMC8382116 DOI: 10.3389/fcvm.2021.662410] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 06/24/2021] [Indexed: 01/01/2023] Open
Abstract
The understanding of the electrophysiological mechanisms that underlie mechanosensitivity of the sinoatrial node (SAN), the primary pacemaker of the heart, has been evolving over the past century. The heart is constantly exposed to a dynamic mechanical environment; as such, the SAN has numerous canonical and emerging mechanosensitive ion channels and signaling pathways that govern its ability to respond to both fast (within second or on beat-to-beat manner) and slow (minutes) timescales. This review summarizes the effects of mechanical loading on the SAN activity and reviews putative candidates, including fast mechanoactivated channels (Piezo, TREK, and BK) and slow mechanoresponsive ion channels [including volume-regulated chloride channels and transient receptor potential (TRP)], as well as the components of mechanochemical signal transduction, which may contribute to SAN mechanosensitivity. Furthermore, we examine the structural foundation for both mechano-electrical and mechanochemical signal transduction and discuss the role of specialized membrane nanodomains, namely, caveolae, in mechanical regulation of both membrane and calcium clock components of the so-called coupled-clock pacemaker system responsible for SAN automaticity. Finally, we emphasize how these mechanically activated changes contribute to the pathophysiology of SAN dysfunction and discuss controversial areas necessitating future investigations. Though the exact mechanisms of SAN mechanosensitivity are currently unknown, identification of such components, their impact into SAN pacemaking, and pathological remodeling may provide new therapeutic targets for the treatment of SAN dysfunction and associated rhythm abnormalities.
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Affiliation(s)
- Daniel Turner
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Chen Kang
- Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - Pietro Mesirca
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Juan Hong
- Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States
| | - Matteo E Mangoni
- Institut de Génomique Fonctionnelle, Université de Montpellier, CNRS, INSERM, Montpellier, France
| | - Alexey V Glukhov
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health, Madison, WI, United States
| | - Rajan Sah
- Cardiovascular Division, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, United States
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Herrera-Pérez S, Campos-Ríos A, Rueda-Ruzafa L, Lamas JA. Contribution of K2P Potassium Channels to Cardiac Physiology and Pathophysiology. Int J Mol Sci 2021; 22:ijms22126635. [PMID: 34205717 PMCID: PMC8234311 DOI: 10.3390/ijms22126635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/08/2021] [Accepted: 06/18/2021] [Indexed: 12/28/2022] Open
Abstract
Years before the first two-pore domain potassium channel (K2P) was cloned, certain ion channels had already been demonstrated to be present in the heart with characteristics and properties usually attributed to the TREK channels (a subfamily of K2P channels). K2P channels were later detected in cardiac tissue by RT-PCR, although the distribution of the different K2P subfamilies in the heart seems to depend on the species analyzed. In order to collect relevant information in this regard, we focus here on the TWIK, TASK and TREK cardiac channels, their putative roles in cardiac physiology and their implication in coronary pathologies. Most of the RNA expression data and electrophysiological recordings available to date support the presence of these different K2P subfamilies in distinct cardiac cells. Likewise, we show how these channels may be involved in certain pathologies, such as atrial fibrillation, long QT syndrome and Brugada syndrome.
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10
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Park DS, Fishman GI. T for Two: T-Box Factors and the Functional Dichotomy of the Conduction System. Circ Res 2020; 127:357-359. [PMID: 32673534 DOI: 10.1161/circresaha.120.317421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- David S Park
- From the Leon H. Charney Division of Cardiology, NYU Grossman School of Medicine, New York
| | - Glenn I Fishman
- From the Leon H. Charney Division of Cardiology, NYU Grossman School of Medicine, New York
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11
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Burnicka-Turek O, Broman MT, Steimle JD, Boukens BJ, Petrenko NB, Ikegami K, Nadadur RD, Qiao Y, Arnolds DE, Yang XH, Patel VV, Nobrega MA, Efimov IR, Moskowitz IP. Transcriptional Patterning of the Ventricular Cardiac Conduction System. Circ Res 2020; 127:e94-e106. [PMID: 32290757 PMCID: PMC8328577 DOI: 10.1161/circresaha.118.314460] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
RATIONALE The heartbeat is organized by the cardiac conduction system (CCS), a specialized network of cardiomyocytes. Patterning of the CCS into atrial node versus ventricular conduction system (VCS) components with distinct physiology is essential for the normal heartbeat. Distinct node versus VCS physiology has been recognized for more than a century, but the molecular basis of this regional patterning is not well understood. OBJECTIVE To study the genetic and genomic mechanisms underlying node versus VCS distinction and investigate rhythm consequences of failed VCS patterning. METHODS AND RESULTS Using mouse genetics, we found that the balance between T-box transcriptional activator, Tbx5, and T-box transcriptional repressor, Tbx3, determined the molecular and functional output of VCS myocytes. Adult VCS-specific removal of Tbx5 or overexpression of Tbx3 re-patterned the fast VCS into slow, nodal-like cells based on molecular and functional criteria. In these cases, gene expression profiling showed diminished expression of genes required for VCS-specific fast conduction but maintenance of expression of genes required for nodal slow conduction physiology. Action potentials of Tbx5-deficient VCS myocytes adopted nodal-specific characteristics, including increased action potential duration and cellular automaticity. Removal of Tbx5 in vivo precipitated inappropriate depolarizations in the atrioventricular (His)-bundle associated with lethal ventricular arrhythmias. TBX5 bound and directly activated cis-regulatory elements at fast conduction channel genes required for fast physiological characteristics of the VCS action potential, defining the identity of the adult VCS. CONCLUSIONS The CCS is patterned entirely as a slow, nodal ground state, with a T-box dependent, physiologically dominant, fast conduction network driven specifically in the VCS. Disruption of the fast VCS gene regulatory network allowed nodal physiology to emerge, providing a plausible molecular mechanism for some lethal ventricular arrhythmias.
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Affiliation(s)
- Ozanna Burnicka-Turek
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Michael T. Broman
- Department of Medicine, The University of Chicago, Chicago, IL, 60637, USA
| | - Jeffrey D. Steimle
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Bastiaan J. Boukens
- Department of Biomedical Engineering, George Washington University, Washington, DC 20052, USA
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Nataliya B. Petrenko
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Penn Cardiovascular Institute, Philadelphia, PA 19104, USA
| | - Kohta Ikegami
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Rangarajan D. Nadadur
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Yun Qiao
- Department of Biomedical Engineering, George Washington University, Washington, DC 20052, USA
| | - David E. Arnolds
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Xinan H. Yang
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Vickas V. Patel
- Discovery Medicine, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Marcelo A. Nobrega
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
| | - Igor R. Efimov
- Department of Biomedical Engineering, George Washington University, Washington, DC 20052, USA
| | - Ivan P. Moskowitz
- Department of Pediatrics, University of Chicago, Chicago, IL 60637, USA
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
- Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA
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12
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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: 19] [Impact Index Per Article: 4.8] [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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13
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A lower X-gate in TASK channels traps inhibitors within the vestibule. Nature 2020; 582:443-447. [PMID: 32499642 DOI: 10.1038/s41586-020-2250-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 03/12/2020] [Indexed: 12/23/2022]
Abstract
TWIK-related acid-sensitive potassium (TASK) channels-members of the two pore domain potassium (K2P) channel family-are found in neurons1, cardiomyocytes2-4 and vascular smooth muscle cells5, where they are involved in the regulation of heart rate6, pulmonary artery tone5,7, sleep/wake cycles8 and responses to volatile anaesthetics8-11. K2P channels regulate the resting membrane potential, providing background K+ currents controlled by numerous physiological stimuli12-15. Unlike other K2P channels, TASK channels are able to bind inhibitors with high affinity, exceptional selectivity and very slow compound washout rates. As such, these channels are attractive drug targets, and TASK-1 inhibitors are currently in clinical trials for obstructive sleep apnoea and atrial fibrillation16. In general, potassium channels have an intramembrane vestibule with a selectivity filter situated above and a gate with four parallel helices located below; however, the K2P channels studied so far all lack a lower gate. Here we present the X-ray crystal structure of TASK-1, and show that it contains a lower gate-which we designate as an 'X-gate'-created by interaction of the two crossed C-terminal M4 transmembrane helices at the vestibule entrance. This structure is formed by six residues (243VLRFMT248) that are essential for responses to volatile anaesthetics10, neurotransmitters13 and G-protein-coupled receptors13. Mutations within the X-gate and the surrounding regions markedly affect both the channel-open probability and the activation of the channel by anaesthetics. Structures of TASK-1 bound to two high-affinity inhibitors show that both compounds bind below the selectivity filter and are trapped in the vestibule by the X-gate, which explains their exceptionally low washout rates. The presence of the X-gate in TASK channels explains many aspects of their physiological and pharmacological behaviour, which will be beneficial for the future development and optimization of TASK modulators for the treatment of heart, lung and sleep disorders.
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14
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Ratte A, Wiedmann F, Kraft M, Katus HA, Schmidt C. Antiarrhythmic Properties of Ranolazine: Inhibition of Atrial Fibrillation Associated TASK-1 Potassium Channels. Front Pharmacol 2019; 10:1367. [PMID: 32038227 PMCID: PMC6988797 DOI: 10.3389/fphar.2019.01367] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 10/28/2019] [Indexed: 12/03/2022] Open
Abstract
Background: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and one of the major causes of cardiovascular morbidity and mortality. Despite good progress within the past years, safe and effective treatment of AF remains an unmet clinical need. The anti-anginal agent ranolazine has been shown to exhibit antiarrhythmic properties via mainly late INa and IKr blockade. This results in prolongation of the atrial action potential duration (APD) and effective refractory period (ERP) with lower effect on ventricular electrophysiology. Furthermore, ranolazine has been shown to be effective in the treatment of AF. TASK-1 is a two-pore domain potassium (K2P) channel that shows nearly atrial specific expression within the human heart and has been found to be upregulated in AF, resulting in shortening the atrial APD in patients suffering from AF. We hypothesized that inhibition TASK-1 contributes to the observed electrophysiological and clinical effects of ranolazine. Methods: We used Xenopus laevis oocytes and CHO-cells as heterologous expression systems for the study of TASK-1 inhibition by ranolazine and molecular drug docking simulations to investigate the ranolazine binding site and binding characteristics. Results: Ranolazine acts as an inhibitor of TASK-1 potassium channels that inhibits TASK-1 currents with an IC50 of 30.6 ± 3.7 µM in mammalian cells and 198.4 ± 1.1 µM in X. laevis oocytes. TASK-1 inhibition by ranolazine is not frequency dependent but shows voltage dependency with a higher inhibitory potency at more depolarized membrane potentials. Ranolazine binds within the central cavity of the TASK-1 inner pore, at the bottom of the selectivity filter. Conclusions: In this study, we show that ranolazine inhibits TASK-1 channels. We suggest that inhibition of TASK-1 may contribute to the observed antiarrhythmic effects of Ranolazine. This puts forward ranolazine as a prototype drug for the treatment of atrial arrhythmia because of its combined efficacy on atrial electrophysiology and lower risk for ventricular side effects.
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Affiliation(s)
- Antonius Ratte
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany.,HCR, Heidelberg Centre for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Felix Wiedmann
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany.,HCR, Heidelberg Centre for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Manuel Kraft
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany.,HCR, Heidelberg Centre for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Hugo A Katus
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany.,HCR, Heidelberg Centre for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
| | - Constanze Schmidt
- Department of Cardiology, University of Heidelberg, Heidelberg, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Heidelberg/Mannheim, University of Heidelberg, Heidelberg, Germany.,HCR, Heidelberg Centre for Heart Rhythm Disorders, University of Heidelberg, Heidelberg, Germany
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15
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Kamatham S, Waters CM, Schwingshackl A, Mancarella S. TREK-1 protects the heart against ischemia-reperfusion-induced injury and from adverse remodeling after myocardial infarction. Pflugers Arch 2019; 471:1263-1272. [PMID: 31511966 DOI: 10.1007/s00424-019-02306-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 08/12/2019] [Accepted: 08/22/2019] [Indexed: 11/28/2022]
Abstract
The TWIK-related K+ channel (TREK-1) is a two-pore-domain potassium channel that produces background leaky potassium currents. TREK-1 has a protective role against ischemia-induced neuronal damage. TREK-1 is also expressed in the heart, but its role in myocardial ischemia-reperfusion (IR)-induced injury has not been examined. In the current study, we used a TREK-1 knockout (KO) mouse model to show that TREK-1 has a critical role in the cardiac I/R-induced injury and during remodeling after myocardial infarction (MI). At baseline, TREK-1 KO mice had similar blood pressure and heart rate as the wild-type (WT) mice. However, the lack of TREK-1 was associated with increased susceptibility to ischemic injury and compromised functional recovery following ex vivo I/R-induced injury. TREK-1 deficiency increased infarct size following permanent coronary artery ligation, resulting in greater systolic dysfunction than the WT counterpart. Electrocardiographic (ECG) analysis revealed QT interval prolongation in TREK-1 KO mice, but normal heart rate (HR). Acutely isolated TREK-1 KO cardiomyocytes exhibited prolonged Ca2+ transient duration associated with action potential duration (APD) prolongation. Our data suggest that TREK-1 has a protective effect against I/R-induced injury and influences the post-MI remodeling processes by regulating membrane potential and maintaining intracellular Ca2+ homeostasis. These data suggest that TREK-1 activation could be an effective strategy to provide cardioprotection against ischemia-induced damage.
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Affiliation(s)
- Samuel Kamatham
- Department of Physiology, University of Tennessee Health Sciences Center, 71 S. Manassas Street, Memphis, TN, 38163, USA
| | - Christopher M Waters
- Department of Physiology, Saha Cardiovascular Research Center, University of Kentucky, Lexington, KY, USA
| | - Andreas Schwingshackl
- Department of Pediatrics, University of California Los Angeles, Los Angeles, CA, USA
| | - Salvatore Mancarella
- Department of Physiology, University of Tennessee Health Sciences Center, 71 S. Manassas Street, Memphis, TN, 38163, USA.
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16
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Lambert M, Capuano V, Boet A, Tesson L, Bertero T, Nakhleh MK, Remy S, Anegon I, Pechoux C, Hautefort A, Rucker-Martin C, Manoury B, Domergue V, Mercier O, Girerd B, Montani D, Perros F, Humbert M, Antigny F. Characterization of Kcnk3-Mutated Rat, a Novel Model of Pulmonary Hypertension. Circ Res 2019; 125:678-695. [PMID: 31347976 DOI: 10.1161/circresaha.119.314793] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
RATIONALE Pulmonary arterial hypertension is a severe lethal cardiopulmonary disease. Loss of function mutations in KCNK3 (potassium channel subfamily K member 3) gene, which encodes an outward rectifier K+ channel, have been identified in pulmonary arterial hypertension patients. OBJECTIVE We have demonstrated that KCNK3 dysfunction is common to heritable and nonheritable pulmonary arterial hypertension and to experimental pulmonary hypertension (PH). Finally, KCNK3 is not functional in mouse pulmonary vasculature. METHODS AND RESULTS Using CRISPR/Cas9 technology, we generated a 94 bp out of frame deletion in exon 1 of Kcnk3 gene and characterized these rats at the electrophysiological, echocardiographic, hemodynamic, morphological, cellular, and molecular levels to decipher the cellular mechanisms associated with loss of KCNK3. Using patch-clamp technique, we validated our transgenic strategy by demonstrating the absence of KCNK3 current in freshly isolated pulmonary arterial smooth muscle cells from Kcnk3-mutated rats. At 4 months of age, echocardiographic parameters revealed shortening of the pulmonary artery acceleration time associated with elevation of the right ventricular systolic pressure. Kcnk3-mutated rats developed more severe PH than wild-type rats after monocrotaline exposure or chronic hypoxia exposure. Kcnk3-mutation induced a lung distal neomuscularization and perivascular extracellular matrix activation. Lungs of Kcnk3-mutated rats were characterized by overactivation of ERK1/2 (extracellular signal-regulated kinase1-/2), AKT (protein kinase B), SRC, and overexpression of HIF1-α (hypoxia-inducible factor-1 α), survivin, and VWF (Von Willebrand factor). Linked with plasma membrane depolarization, reduced endothelial-NOS expression and desensitization of endothelial-derived hyperpolarizing factor, Kcnk3-mutated rats presented predisposition to vasoconstriction of pulmonary arteries and a severe loss of sildenafil-induced pulmonary arteries relaxation. Moreover, we showed strong alteration of right ventricular cardiomyocyte excitability. Finally, Kcnk3-mutated rats developed age-dependent PH associated with low serum-albumin concentration. CONCLUSIONS We established the first Kcnk3-mutated rat model of PH. Our results confirm that KCNK3 loss of function is a key event in pulmonary arterial hypertension pathogenesis. This model presents new opportunities for understanding the initiating mechanisms of PH and testing biologically relevant therapeutic molecules in the context of PH.
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Affiliation(s)
- Mélanie Lambert
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Véronique Capuano
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Angèle Boet
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Laurent Tesson
- Centre de Recherche en Transplantation et Immunologie UMR 1064, INSERM, Université de Nantes, France (L.T., S.R., I.A.).,PTransgenic Rat ImmunoPhenomic (TRIP) facility Nantes, Nantes, France (L.T., S.R., I.A.)
| | - Thomas Bertero
- Université Côte d'Azur, CNRS, IPMC, Valbonne, France (T.B.)
| | - Morad K Nakhleh
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Séverine Remy
- Centre de Recherche en Transplantation et Immunologie UMR 1064, INSERM, Université de Nantes, France (L.T., S.R., I.A.).,PTransgenic Rat ImmunoPhenomic (TRIP) facility Nantes, Nantes, France (L.T., S.R., I.A.)
| | - Ignacio Anegon
- Centre de Recherche en Transplantation et Immunologie UMR 1064, INSERM, Université de Nantes, France (L.T., S.R., I.A.).,PTransgenic Rat ImmunoPhenomic (TRIP) facility Nantes, Nantes, France (L.T., S.R., I.A.)
| | - Christine Pechoux
- GABI, INRA, AgroParisTech, Université Paris-Saclay, 78350 Jouy-en-Josas, France (C.P.)
| | - Aurélie Hautefort
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Catherine Rucker-Martin
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Boris Manoury
- Signalisation et Physiopathologie Cardiovasculaire - UMR_S 1180, Univ. Paris-Sud, INSERM, Université Paris-Saclay, Châtenay-Malabry, France (B.M.)
| | - Valérie Domergue
- Animal Facility, Institut Paris Saclay d'Innovation Thérapeutique (UMS IPSIT), Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France (V.D.)
| | - Olaf Mercier
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Barbara Girerd
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - David Montani
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Frédéric Perros
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Canada (F.P.)
| | - Marc Humbert
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
| | - Fabrice Antigny
- From the University Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M. H., F.A.).,Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Centre de Référence de l'Hypertension Pulmonaire, Hôpital Bicêtre, Le Kremlin Bicêtre, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.).,Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson, France (M.L., V.C., A.B., M.K.N., A.H., C.R.-M., O.M., B.G., D.M., F.P., M.H., F.A.)
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17
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Iqbal F, Thompson AJ, Riaz S, Pehar M, Rice T, Syed NI. Anesthetics: from modes of action to unconsciousness and neurotoxicity. J Neurophysiol 2019; 122:760-787. [PMID: 31242059 DOI: 10.1152/jn.00210.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Modern anesthetic compounds and advanced monitoring tools have revolutionized the field of medicine, allowing for complex surgical procedures to occur safely and effectively. Faster induction times and quicker recovery periods of current anesthetic agents have also helped reduce health care costs significantly. Moreover, extensive research has allowed for a better understanding of anesthetic modes of action, thus facilitating the development of more effective and safer compounds. Notwithstanding the realization that anesthetics are a prerequisite to all surgical procedures, evidence is emerging to support the notion that exposure of the developing brain to certain anesthetics may impact future brain development and function. Whereas the data in support of this postulate from human studies is equivocal, the vast majority of animal research strongly suggests that anesthetics are indeed cytotoxic at multiple brain structure and function levels. In this review, we first highlight various modes of anesthetic action and then debate the evidence of harm from both basic science and clinical studies perspectives. We present evidence from animal and human studies vis-à-vis the possible detrimental effects of anesthetic agents on both the young developing and the elderly aging brain while discussing potential ways to mitigate these effects. We hope that this review will, on the one hand, invoke debate vis-à-vis the evidence of anesthetic harm in young children and the elderly, and on the other hand, incentivize the search for better and less toxic anesthetic compounds.
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Affiliation(s)
- Fahad Iqbal
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Andrew J Thompson
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Neuroscience, Faculty of Science, University of Calgary, Calgary, Alberta, Canada
| | - Saba Riaz
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Marcus Pehar
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Tiffany Rice
- Department of Anesthesiology, Perioperative and Pain Medicine, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada
| | - Naweed I Syed
- Vi Riddell Pain Program, Alberta Children's Hospital Research Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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18
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Rinné S, Kiper AK, Vowinkel KS, Ramírez D, Schewe M, Bedoya M, Aser D, Gensler I, Netter MF, Stansfeld PJ, Baukrowitz T, Gonzalez W, Decher N. The molecular basis for an allosteric inhibition of K +-flux gating in K 2P channels. eLife 2019; 8:39476. [PMID: 30803485 PMCID: PMC6391080 DOI: 10.7554/elife.39476] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 02/06/2019] [Indexed: 01/05/2023] Open
Abstract
Two-pore-domain potassium (K2P) channels are key regulators of many physiological and pathophysiological processes and thus emerged as promising drug targets. As for other potassium channels, there is a lack of selective blockers, since drugs preferentially bind to a conserved binding site located in the central cavity. Thus, there is a high medical need to identify novel drug-binding sites outside the conserved lipophilic central cavity and to identify new allosteric mechanisms of channel inhibition. Here, we identified a novel binding site and allosteric inhibition mechanism, disrupting the recently proposed K+-flux gating mechanism of K2P channels, which results in an unusual voltage-dependent block of leak channels belonging to the TASK subfamily. The new binding site and allosteric mechanism of inhibition provide structural and mechanistic insights into the gating of TASK channels and the basis for the drug design of a new class of potent blockers targeting specific types of K2P channels.
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Affiliation(s)
- Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Kirsty S Vowinkel
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - David Ramírez
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca, Talca, Chile.,Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Talca, Chile
| | - Marcus Schewe
- Institute of Physiology, University of Kiel, Kiel, Germany
| | - Mauricio Bedoya
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca, Talca, Chile
| | - Diana Aser
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Isabella Gensler
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Michael F Netter
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Phillip J Stansfeld
- Structural Bioinformatics and Computational Biochemistry Unit, Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | | | - Wendy Gonzalez
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca, Talca, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Talca, Talca, Chile
| | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
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19
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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: 0.2] [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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20
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Zhang H, Tao M, Kang P, Guo J, Xuan L, Tang B, Gao Q, Wang H. [Changes of two-pore K+ channel TASK-1 in diabetic myocardial injury in rats]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2018; 38:1228-1233. [PMID: 30377119 DOI: 10.3969/j.issn.1673-4254.2018.10.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To investigate the changes of the two- pore K+ channel TASK-1 in diabetic rats with myocardial injury. METHODS Thirty-six SD rats were divided into normal group (N), diabetes at 4 weeks (DM 4W) group, and diabetes at 8 weeks (DM 8W) group. The cardiac functions of the rats were determined using cardiac ultrasonography, and the body weight and heart weight of the rats at different time points were measured to calculate the heart/body weight ratio (HW/BW). Myocardial fibrosis in the rats was assessed using Masson's staining. The protein expression of TASK-1 in the myocardium was detected using Western blotting. Whole- cell patch clamp technique was used to record the action potential duration (APD) and twopore domain potassium channel TASK- 1 current in acutely isolated rat ventricular myocytes. meanwhile, The inhibition of TASK-1 current was observed by the TASK-1 specific inhibitor ML-365. RESULTS Compared with the normal group, the diabetic rats showed significantly increased HW/BW (P < 0.05), end- diastole left ventricular diameter (LVIDd), end- systolic left ventricular diameter (LVIDs), and TASK-1 protein expression, with obviously decreased left ventricular diameter shortening rate (FS) and ejection fraction (EF) (P < 0.01). Masson staining showed that in diabetic rats, the collagen fibers were thickened, interwoven into a network with uneven arrangement and increased deposition. Compared with DM 4W group, the rats in DM 8W group exhibited progressive increases in LVIDd, LVIDs, HW/BW, and TASK-1 expression (P < 0.01 or 0.05); FS and EF were further decreased (P < 0.01). Masson staining showed worsened morphological changes of the myocardium with increased deposition. Compared with that in the normal group, the current of TASK- 1 in diabetic rats at 8 weeks was significantly reduced (P < 0.01) and the duration of action potential was extended (P < 0.05). The TASK-1 current was successfully inhibited by ML-365. CONCLUSIONS Diabetes can induce myocardial fibrosis and aggravate myocardial injury possibly in relation to changes in the protein expression and current of the two-port potassium channel TASK-1.
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Affiliation(s)
- Heng Zhang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - Min Tao
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - Pinfang Kang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - Jianlu Guo
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - Ling Xuan
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - Bi Tang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
| | - Qin Gao
- Department of Physiology, Bengbu Medical College, Bengbu 233030, China
| | - Hongju Wang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Bengbu Medical College, Bengbu 233004, China
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21
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Chai S, Wan X, Ramirez-Navarro A, Tesar PJ, Kaufman ES, Ficker E, George AL, Deschênes I. Physiological genomics identifies genetic modifiers of long QT syndrome type 2 severity. J Clin Invest 2018; 128:1043-1056. [PMID: 29431731 DOI: 10.1172/jci94996] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 01/02/2018] [Indexed: 12/11/2022] Open
Abstract
Congenital long QT syndrome (LQTS) is an inherited channelopathy associated with life-threatening arrhythmias. LQTS type 2 (LQT2) is caused by mutations in KCNH2, which encodes the potassium channel hERG. We hypothesized that modifier genes are partly responsible for the variable phenotype severity observed in some LQT2 families. Here, we identified contributors to variable expressivity in an LQT2 family by using induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) and whole exome sequencing in a synergistic manner. We found that iPSC-CMs recapitulated the clinical genotype-phenotype discordance in vitro. Importantly, iPSC-CMs derived from the severely affected LQT2 patients displayed prolonged action potentials compared with cells from mildly affected first-degree relatives. The iPSC-CMs derived from all patients with hERG R752W mutation displayed lower IKr amplitude. Interestingly, iPSC-CMs from severely affected mutation-positive individuals exhibited greater L-type Ca2+ current. Whole exome sequencing identified variants of KCNK17 and the GTP-binding protein REM2, providing biologically plausible explanations for this variable expressivity. Genome editing to correct a REM2 variant reversed the enhanced L-type Ca2+ current and prolonged action potential observed in iPSC-CMs from severely affected individuals. Thus, our findings showcase the power of combining complementary physiological and genomic analyses to identify genetic modifiers and potential therapeutic targets of a monogenic disorder. Furthermore, we propose that this strategy can be deployed to unravel myriad confounding pathologies displaying variable expressivity.
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Affiliation(s)
- Sam Chai
- Department of Physiology and Biophysics.,Heart and Vascular Research Center, Department of Medicine, and
| | - Xiaoping Wan
- Heart and Vascular Research Center, Department of Medicine, and
| | | | - Paul J Tesar
- Department of Genetics, Case Western Reserve University, Cleveland, Ohio, USA
| | | | - Eckhard Ficker
- Heart and Vascular Research Center, Department of Medicine, and
| | - Alfred L George
- Department of Pharmacology, Northwestern University, Chicago, Illinois, USA
| | - Isabelle Deschênes
- Department of Physiology and Biophysics.,Heart and Vascular Research Center, Department of Medicine, and
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22
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Lambert M, Boet A, Rucker-Martin C, Mendes-Ferreira P, Capuano V, Hatem S, Adão R, Brás-Silva C, Hautefort A, Michel JB, Dorfmuller P, Fadel E, Kotsimbos T, Price L, Jourdon P, Montani D, Humbert M, Perros F, Antigny F. Loss of KCNK3 is a hallmark of RV hypertrophy/dysfunction associated with pulmonary hypertension. Cardiovasc Res 2018; 114:880-893. [DOI: 10.1093/cvr/cvy016] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 01/18/2018] [Indexed: 11/13/2022] Open
Affiliation(s)
- Mélanie Lambert
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Angèle Boet
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
- Réanimation des Cardiopathies Congénitales, Univ. Paris-Sud, Hôpital-Marie-Lannelongue, Le Plessis-Robinson, France
| | - Catherine Rucker-Martin
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Pedro Mendes-Ferreira
- Department of Surgery and Physiology, Faculty of Medicine, Cardiovascular Research Centre, University of Porto, 4200-319 Porto, Portugal
| | - Véronique Capuano
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Stéphane Hatem
- Département de Cardiologie, INSERM UMR_S1166, ICAN, Assistance Publique-Hôpitaux de Paris, Hôpital Pitié-Salpêtrière 75013, France
| | - Rui Adão
- Department of Surgery and Physiology, Faculty of Medicine, Cardiovascular Research Centre, University of Porto, 4200-319 Porto, Portugal
| | - Carmen Brás-Silva
- Department of Surgery and Physiology, Faculty of Medicine, Cardiovascular Research Centre, University of Porto, 4200-319 Porto, Portugal
| | - Aurélie Hautefort
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Jean-Baptiste Michel
- INSERM UMR_S1148, Paris7, Denis Diderot University, Xavier Bichat Hospital, 75018, Paris, France
| | - Peter Dorfmuller
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Elie Fadel
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
- Service de Chirurgie Thoracique, Centre Chirurgical Marie Lannelongue, Le Plessis-Robinson, France
| | - Tom Kotsimbos
- Department of Respiratory Medicine, Alfred Hospital, Monash University, Melbourne, VIC 3181, Australia
| | - Laura Price
- National Pulmonary Hypertension Service, Royal Brompton Hospital, London SW3 6NP, UK
| | - Philippe Jourdon
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - David Montani
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Marc Humbert
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Frédéric Perros
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
| | - Fabrice Antigny
- Univ. Paris-Sud, Faculté de Médecine, Université Paris-Saclay, Le Kremlin Bicêtre 94270, France
- Assistance Publique Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin Bicêtre 94270, France
- Inserm UMR_S 999, Hôpital Marie Lannelongue, Le Plessis Robinson 92350, France
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23
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Cázares-Ordoñez V, Pardo L. Kv10.1 potassium channel: from the brain to the tumors. Biochem Cell Biol 2017; 95:531-536. [DOI: 10.1139/bcb-2017-0062] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The KCNH1 gene encodes the Kv10.1 (Eag1) ion channel, a member of the EAG (ether-à-go-go) family of voltage-gated potassium channels. Recent studies have demonstrated that KCHN1 mutations are implicated in Temple–Baraitser and Zimmermann–Laband syndromes and other forms of developmental deficits that all present with mental retardation and epilepsy, suggesting that Kv10.1 might be important for cognitive development in humans. Although the Kv10.1 channel is mainly expressed in the mammalian brain, its ectopic expression occurs in 70% of human cancers. Cancer cells and tumors expressing Kv10.1 acquire selective advantages that favor cancer progression through molecular mechanisms that involve several cellular pathways, indicating that protein–protein interactions may be important for Kv10.1 influence in cell proliferation and tumorigenesis. Several studies on transcriptional and post-transcriptional regulation of Kv10.1 expression have shown interesting mechanistic insights about Kv10.1 role in oncogenesis, increasing the importance of identifying the cellular factors that regulate Kv10.1 expression in tumors.
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Affiliation(s)
- V. Cázares-Ordoñez
- Oncophysiology Group, Max Planck Institute of Experimental Medicine, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany
- Oncophysiology Group, Max Planck Institute of Experimental Medicine, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany
| | - L.A. Pardo
- Oncophysiology Group, Max Planck Institute of Experimental Medicine, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany
- Oncophysiology Group, Max Planck Institute of Experimental Medicine, Hermann-Rein-Strasse 3, 37075 Göttingen, Germany
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24
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Heijman J, Ghezelbash S, Dobrev D. Investigational antiarrhythmic agents: promising drugs in early clinical development. Expert Opin Investig Drugs 2017; 26:897-907. [PMID: 28691539 PMCID: PMC6324729 DOI: 10.1080/13543784.2017.1353601] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
INTRODUCTION Although there have been important technological advances for the treatment of cardiac arrhythmias (e.g., catheter ablation technology), antiarrhythmic drugs (AADs) remain the cornerstone therapy for the majority of patients with arrhythmias. Most of the currently available AADs were coincidental findings and did not result from a systematic development process based on known arrhythmogenic mechanisms and specific targets. During the last 20 years, our understanding of cardiac electrophysiology and fundamental arrhythmia mechanisms has increased significantly, resulting in the identification of new potential targets for mechanism-based antiarrhythmic therapy. Areas covered: Here, we review the state-of-the-art in arrhythmogenic mechanisms and AAD therapy. Thereafter, we focus on a number of antiarrhythmic targets that have received significant attention recently: atrial-specific K+-channels, the late Na+-current, the cardiac ryanodine-receptor channel type-2, and the small-conductance Ca2+-activated K+-channel. We highlight for each of these targets available antiarrhythmic agents and the evidence for their antiarrhythmic effect in animal models and early clinical development. Expert opinion: Targeting AADs to specific subgroups of well-phenotyped patients is likely necessary to detect improved outcomes that may be obscured in the population at large. In addition, specific combinations of selective AADs may have synergistic effects and may enable a mechanism-based tailored antiarrhythmic therapy.
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Affiliation(s)
- Jordi Heijman
- Department of Cardiology, Cardiovascular Research Institute Maastricht, Faculty of Health, Medicine, and Life Sciences, Maastricht University, Maastricht, The Netherlands
| | - Shokoufeh Ghezelbash
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Essen, Germany
| | - Dobromir Dobrev
- Institute of Pharmacology, West German Heart and Vascular Center, Faculty of Medicine, University Duisburg-Essen, Essen, Germany
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25
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Extraoral Taste Receptor Discovery: New Light on Ayurvedic Pharmacology. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2017. [PMID: 28642799 PMCID: PMC5469997 DOI: 10.1155/2017/5435831] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
More and more research studies are revealing unexpectedly important roles of taste for health and pathogenesis of various diseases. Only recently it has been shown that taste receptors have many extraoral locations (e.g., stomach, intestines, liver, pancreas, respiratory system, heart, brain, kidney, urinary bladder, pancreas, adipose tissue, testis, and ovary), being part of a large diffuse chemosensory system. The functional implications of these taste receptors widely dispersed in various organs or tissues shed a new light on several concepts used in ayurvedic pharmacology (dravyaguna vijnana), such as taste (rasa), postdigestive effect (vipaka), qualities (guna), and energetic nature (virya). This review summarizes the significance of extraoral taste receptors and transient receptor potential (TRP) channels for ayurvedic pharmacology, as well as the biological activities of various types of phytochemical tastants from an ayurvedic perspective. The relative importance of taste (rasa), postdigestive effect (vipaka), and energetic nature (virya) as ethnopharmacological descriptors within Ayurveda boundaries will also be discussed.
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26
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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: 3.7] [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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27
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Decher N, Kiper AK, Rinné S. Stretch-activated potassium currents in the heart: Focus on TREK-1 and arrhythmias. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017; 130:223-232. [PMID: 28526352 DOI: 10.1016/j.pbiomolbio.2017.05.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 05/09/2017] [Accepted: 05/15/2017] [Indexed: 12/26/2022]
Abstract
This review focuses on the role and the molecular candidates of the cardiac stretch-activated potassium current (SAK). The functional properties of the two-pore domain potassium (K2P) channel TREK-1, a major candidate for the cardiac SAK, are analyzed and the molecular mechanism of stretch-activation in K2P potassium channels is discussed. Furthermore, the functional modulation of TREK-1 by different cardiac interaction partners, as well as evidence for the functional role of the stretch-dependent TREK-1 and its putative subunits in the heart is reviewed. In addition, we summarize the recent evidence that TREK-1 is involved in the pathogenesis of human cardiac arrhythmias.
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Affiliation(s)
- Niels Decher
- Institute for Physiology and Pathophysiology, AG Vegetative Physiology, Deutschhausstrasse 1-2, 35037 Marburg, Germany.
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, AG Vegetative Physiology, Deutschhausstrasse 1-2, 35037 Marburg, Germany
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, AG Vegetative Physiology, Deutschhausstrasse 1-2, 35037 Marburg, Germany
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28
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Murtaza G, Mermer P, Goldenberg A, Pfeil U, Paddenberg R, Weissmann N, Lochnit G, Kummer W. TASK-1 potassium channel is not critically involved in mediating hypoxic pulmonary vasoconstriction of murine intra-pulmonary arteries. PLoS One 2017; 12:e0174071. [PMID: 28301582 PMCID: PMC5354433 DOI: 10.1371/journal.pone.0174071] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 03/02/2017] [Indexed: 11/26/2022] Open
Abstract
The two-pore domain potassium channel KCNK3 (TASK-1) is expressed in rat and human pulmonary artery smooth muscle cells. There, it is associated with hypoxia-induced signalling, and its dysfunction is linked to pathogenesis of human pulmonary hypertension. We here aimed to determine its role in hypoxic pulmonary vasoconstriction (HPV) in the mouse, and hence the suitability of this model for further mechanistic investigations, using appropriate inhibitors and TASK-1 knockout (KO) mice. RT-PCR revealed expression of TASK-1 mRNA in murine lungs and pre-acinar pulmonary arteries. Protein localization by immunohistochemistry and western blot was unreliable since all antibodies produced labelling also in TASK-1 KO organs/tissues. HPV was investigated by videomorphometric analysis of intra- (inner diameter: 25–40 μm) and pre-acinar pulmonary arteries (inner diameter: 41–60 μm). HPV persisted in TASK-1 KO intra-acinar arteries. Pre-acinar arteries developed initial HPV, but the response faded earlier (after 30 min) in KO vessels. This HPV pattern was grossly mimicked by the TASK-1 inhibitor anandamide in wild-type vessels. Hypoxia-provoked rise in pulmonary arterial pressure (PAP) in isolated ventilated lungs was affected neither by TASK-1 gene deficiency nor by the TASK-1 inhibitor A293. TASK-1 is dispensable for initiating HPV of murine intra-pulmonary arteries, but participates in sustained HPV specifically in pre-acinar arteries. This does not translate into abnormal rise in PAP. While there is compelling evidence that TASK-1 is involved in the pathogenesis of pulmonary arterial hypertension in humans, the mouse does not appear to serve as a suitable model to study the underlying molecular mechanisms.
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Affiliation(s)
- Ghulam Murtaza
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
- * E-mail:
| | - Petra Mermer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Anna Goldenberg
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Uwe Pfeil
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Renate Paddenberg
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
| | - Nobert Weissmann
- Universities of Giessen and Marburg Lung Center, Justus-Liebig-University, Giessen, Germany
- German Center for Lung Research, Excellence Cluster Cardio-Pulmonary System, Justus-Liebig-University, Giessen, Germany
| | - Guenter Lochnit
- Institute of Biochemistry, Faculty of Medicine, Justus-Liebig University, Giessen, Germany
| | - Wolfgang Kummer
- Institute of Anatomy and Cell Biology, Justus-Liebig-University, Giessen, Germany
- German Center for Lung Research, Excellence Cluster Cardio-Pulmonary System, Justus-Liebig-University, Giessen, Germany
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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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30
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Complex Locomotion Behavior Changes Are Induced in Caenorhabditis elegans by the Lack of the Regulatory Leak K+ Channel TWK-7. Genetics 2016; 204:683-701. [PMID: 27535928 DOI: 10.1534/genetics.116.188896] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 08/06/2016] [Indexed: 11/18/2022] Open
Abstract
The change of locomotion activity in response to external cues is a considerable achievement of animals and is required for escape responses, foraging, and other complex behaviors. Little is known about the molecular regulators of such an adaptive locomotion. The conserved eukaryotic two-pore domain potassium (K2P) channels have been recognized as regulatory K+ channels that modify the membrane potential of cells, thereby affecting, e.g., rhythmic muscle activity. By using the Caenorhabditis elegans system combined with cell-type-specific approaches and locomotion in-depth analyses, here, we found that the loss of K2P channel TWK-7 increases the locomotor activity of worms during swimming and crawling in a coordinated mode. Moreover, loss of TWK-7 function results in a hyperactive state that (although less pronounced) resembles the fast, persistent, and directed forward locomotion behavior of stimulated C. elegans TWK-7 is expressed in several head neurons as well as in cholinergic excitatory and GABAergic inhibitory motor neurons. Remarkably, the abundance of TWK-7 in excitatory B-type and inhibitory D-type motor neurons affected five central aspects of adaptive locomotion behavior: velocity/frequency, wavelength/amplitude, direction, duration, and straightness. Hence, we suggest that TWK-7 activity might represent a means to modulate a complex locomotion behavior at the level of certain types of motor neurons.
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31
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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: 4.6] [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
The QT interval reflects the time between the depolarization of ventricles until their repolarization and is usually used as a predictive marker for the occurrence of arrhythmias. This parameter varies with the heart rate, expressed as the RR interval (time between two successive ventricular depolarizations). To calculate the QT independently of the RR, correction formulae are currently used. In mice, the QT-RR relationship as such has never been studied in conscious animals, and correction formulas are mainly empirical. In the present paper we studied how QT varies when the RR changes physiologically (comparison of nocturnal and diurnal periods) or after dosing mice with tachycardic agents (norepinephrine or nitroprusside). Our results show that there is significant variability of QT and RR in a given condition, resulting in the need to average at least 200 consecutive complexes to accurately compare the QT. Even following this method, no obvious shortening of the QT was observed with increased heart rate, regardless of whether or not this change occurs abruptly. In conclusion, the relationship between QT and RR in mice is weak, which renders the use of correction formulae inappropriate and misleading in this species.
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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: 3.4] [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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Skarsfeldt MA, Jepps TA, Bomholtz SH, Abildgaard L, Sørensen US, Gregers E, Svendsen JH, Diness JG, Grunnet M, Schmitt N, Olesen SP, Bentzen BH. pH-dependent inhibition of K₂P3.1 prolongs atrial refractoriness in whole hearts. Pflugers Arch 2016; 468:643-54. [PMID: 26729267 DOI: 10.1007/s00424-015-1779-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 12/20/2015] [Indexed: 12/21/2022]
Abstract
In isolated human atrial cardiomyocytes, inhibition of K2P3.1 K(+) channels results in action potential (action potential duration (APD)) prolongation. It has therefore been postulated that K2P3.1 (KCNK3), together with K2P9.1 (KCNK9), could represent novel drug targets for the treatment of atrial fibrillation (AF). However, it is unknown whether these findings in isolated cells translate to the whole heart. The purposes of this study were to investigate the expression levels of KCNK3 and KCNK9 in human hearts and two relevant rodent models and determine the antiarrhythmic potential of K2P3.1 inhibition in isolated whole-heart preparations. By quantitative PCR, we found that KCNK3 is predominantly expressed in human atria whereas KCNK9 was not detectable in heart human tissue. No differences were found between patients in AF or sinus rhythm. The expression in guinea pig heart resembled humans whereas rats displayed a more uniform expression of KCNK3 between atria and ventricle. In voltage-clamp experiments, ML365 and A293 were found to be potent and selective inhibitors of K2P3.1, but at pH 7.4, they failed to prolong atrial APD and refractory period (effective refractory period (ERP)) in isolated perfused rat and guinea pig hearts. At pH 7.8, which augments K2P3.1 currents, pharmacological channel inhibition produced a significant prolongation of atrial ERP (11.6 %, p = 0.004) without prolonging ventricular APD but did not display a significant antiarrhythmic effect in our guinea pig AF model (3/8 hearts converted on A293 vs 0/7 hearts in time-matched controls). These results suggest that when K2P3.1 current is augmented, K2P3.1 inhibition leads to atrial-specific prolongation of ERP; however, this ERP prolongation did not translate into significant antiarrhythmic effects in our AF model.
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MESH Headings
- Action Potentials
- Adolescent
- Adult
- Animals
- Arrhythmias, Cardiac/metabolism
- Arrhythmias, Cardiac/physiopathology
- Atrial Function
- Cells, Cultured
- Female
- Guinea Pigs
- Heart Atria/cytology
- Heart Atria/metabolism
- Heart Ventricles/cytology
- Heart Ventricles/metabolism
- Humans
- Hydrogen-Ion Concentration
- Male
- Middle Aged
- Myocytes, Cardiac/metabolism
- Myocytes, Cardiac/physiology
- Nerve Tissue Proteins/antagonists & inhibitors
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Potassium Channels, Tandem Pore Domain/antagonists & inhibitors
- Potassium Channels, Tandem Pore Domain/genetics
- Potassium Channels, Tandem Pore Domain/metabolism
- Protons
- Rats
- Rats, Wistar
- Refractory Period, Electrophysiological
- Species Specificity
- Ventricular Function
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Affiliation(s)
- Mark A Skarsfeldt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Thomas A Jepps
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Sofia H Bomholtz
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
- Acesion Pharma, Copenhagen, Denmark
| | | | | | - Emilie Gregers
- Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
- Department of Medicine and Surgery, Faculty of Health and Mediacl Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jesper H Svendsen
- Laboratory of Molecular Cardiology, Department of Cardiology, The Heart Centre, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Nicole Schmitt
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Søren-Peter Olesen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Bo H Bentzen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark.
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36
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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 DOI: 10.1124/mol.115.100107] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [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: 146] [Impact Index Per Article: 16.2] [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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Bandulik S, Tauber P, Lalli E, Barhanin J, Warth R. Two-pore domain potassium channels in the adrenal cortex. Pflugers Arch 2015; 467:1027-42. [PMID: 25339223 PMCID: PMC4428839 DOI: 10.1007/s00424-014-1628-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 10/02/2014] [Accepted: 10/03/2014] [Indexed: 12/31/2022]
Abstract
The physiological control of steroid hormone secretion from the adrenal cortex depends on the function of potassium channels. The "two-pore domain K(+) channels" (K2P) TWIK-related acid sensitive K(+) channel 1 (TASK1), TASK3, and TWIK-related K(+) channel 1 (TREK1) are strongly expressed in adrenocortical cells. They confer a background K(+) conductance to these cells which is important for the K(+) sensitivity as well as for angiotensin II and adrenocorticotropic hormone-dependent stimulation of aldosterone and cortisol synthesis. Mice with single deletions of the Task1 or Task3 gene as well as Task1/Task3 double knockout mice display partially autonomous aldosterone synthesis. It appears that TASK1 and TASK3 serve different functions: TASK1 affects cell differentiation and prevents expression of aldosterone synthase in the zona fasciculata, while TASK3 controls aldosterone secretion in glomerulosa cells. TREK1 is involved in the regulation of cortisol secretion in fasciculata cells. These data suggest that a disturbed function of K2P channels could contribute to adrenocortical pathologies in humans.
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Affiliation(s)
- Sascha Bandulik
- Medical Cell Biology, University of Regensburg, Universitaetsstrasse 31, 93053, Regensburg, Germany,
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Rinné S, Kiper AK, Schlichthörl G, Dittmann S, Netter MF, Limberg SH, Silbernagel N, Zuzarte M, Moosdorf R, Wulf H, Schulze-Bahr E, Rolfes C, Decher N. TASK-1 and TASK-3 may form heterodimers in human atrial cardiomyocytes. J Mol Cell Cardiol 2015; 81:71-80. [DOI: 10.1016/j.yjmcc.2015.01.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 12/30/2014] [Accepted: 01/27/2015] [Indexed: 11/29/2022]
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Renigunta V, Schlichthörl G, Daut J. Much more than a leak: structure and function of K₂p-channels. Pflugers Arch 2015; 467:867-94. [PMID: 25791628 DOI: 10.1007/s00424-015-1703-7] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 03/09/2015] [Indexed: 11/27/2022]
Abstract
Over the last decade, we have seen an enormous increase in the number of experimental studies on two-pore-domain potassium channels (K2P-channels). The collection of reviews and original articles compiled for this special issue of Pflügers Archiv aims to give an up-to-date summary of what is known about the physiology and pathophysiology of K2P-channels. This introductory overview briefly describes the structure of K2P-channels and their function in different organs. Its main aim is to provide some background information for the 19 reviews and original articles of this special issue of Pflügers Archiv. It is not intended to be a comprehensive review; instead, this introductory overview focuses on some unresolved questions and controversial issues, such as: Do K2P-channels display voltage-dependent gating? Do K2P-channels contribute to the generation of action potentials? What is the functional role of alternative translation initiation? Do K2P-channels have one or two or more gates? We come to the conclusion that we are just beginning to understand the extremely complex regulation of these fascinating channels, which are often inadequately described as 'leak channels'.
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Affiliation(s)
- Vijay Renigunta
- Institute of Physiology and Pathophysiology, Marburg University, 35037, Marburg, Germany
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Friedrich C, Rinné S, Zumhagen S, Kiper AK, Silbernagel N, Netter MF, Stallmeyer B, Schulze-Bahr E, Decher N. Gain-of-function mutation in TASK-4 channels and severe cardiac conduction disorder. EMBO Mol Med 2015; 6:937-51. [PMID: 24972929 PMCID: PMC4119356 DOI: 10.15252/emmm.201303783] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Analyzing a patient with progressive and severe cardiac conduction disorder combined with idiopathic ventricular fibrillation (IVF), we identified a splice site mutation in the sodium channel gene SCN5A. Due to the severe phenotype, we performed whole-exome sequencing (WES) and identified an additional mutation in the KCNK17 gene encoding the K2P potassium channel TASK-4. The heterozygous change (c.262G>A) resulted in the p.Gly88Arg mutation in the first extracellular pore loop. Mutant TASK-4 channels generated threefold increased currents, while surface expression was unchanged, indicating enhanced conductivity. When co-expressed with wild-type channels, the gain-of-function by G88R was conferred in a dominant-active manner. We demonstrate that KCNK17 is strongly expressed in human Purkinje cells and that overexpression of G88R leads to a hyperpolarization and strong slowing of the upstroke velocity of spontaneously beating HL-1 cells. Thus, we propose that a gain-of-function by TASK-4 in the conduction system might aggravate slowed conductivity by the loss of sodium channel function. Moreover, WES supports a second hit-hypothesis in severe arrhythmia cases and identified KCNK17 as a novel arrhythmia gene.
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Affiliation(s)
- Corinna Friedrich
- Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Münster, Germany
| | - Susanne Rinné
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Sven Zumhagen
- Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Münster, Germany
| | - Aytug K Kiper
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Nicole Silbernagel
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Michael F Netter
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
| | - Birgit Stallmeyer
- Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Münster, Germany
| | - Eric Schulze-Bahr
- Department of Cardiovascular Medicine, Institute for Genetics of Heart Diseases (IfGH), University Hospital Münster, Münster, Germany
| | - Niels Decher
- Institute of Physiology and Pathophysiology, Vegetative Physiology, University of Marburg, Marburg, Germany
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Feliciangeli S, Chatelain FC, Bichet D, Lesage F. The family of K2P channels: salient structural and functional properties. J Physiol 2015; 593:2587-603. [PMID: 25530075 DOI: 10.1113/jphysiol.2014.287268] [Citation(s) in RCA: 148] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 12/10/2014] [Indexed: 12/11/2022] Open
Abstract
Potassium channels participate in many biological functions, from ion homeostasis to generation and modulation of the electrical membrane potential. They are involved in a large variety of diseases. In the human genome, 15 genes code for K(+) channels with two pore domains (K2P ). These channels form dimers of pore-forming subunits that produce background conductances finely regulated by a range of natural and chemical effectors, including signalling lipids, temperature, pressure, pH, antidepressants and volatile anaesthetics. Since the cloning of TWIK1, the prototypical member of this family, a lot of work has been carried out on their structure and biology. These studies are still in progress, but data gathered so far show that K2P channels are central players in many processes, including ion homeostasis, hormone secretion, cell development and excitability. A growing number of studies underline their implication in physiopathological mechanisms, such as vascular and pulmonary hypertension, cardiac arrhythmias, nociception, neuroprotection and depression. This review gives a synthetic view of the most noticeable features of these channels.
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Affiliation(s)
- Sylvain Feliciangeli
- LabEx ICST, Institut de Pharmacologie Moléculaire et Cellulaire, CNRS and Université de Nice-Sophia Antipolis, 660 Route des Lucioles, 06560, Valbonne, France
| | - Frank C Chatelain
- LabEx ICST, Institut de Pharmacologie Moléculaire et Cellulaire, CNRS and Université de Nice-Sophia Antipolis, 660 Route des Lucioles, 06560, Valbonne, France
| | - Delphine Bichet
- LabEx ICST, Institut de Pharmacologie Moléculaire et Cellulaire, CNRS and Université de Nice-Sophia Antipolis, 660 Route des Lucioles, 06560, Valbonne, France
| | - Florian Lesage
- LabEx ICST, Institut de Pharmacologie Moléculaire et Cellulaire, CNRS and Université de Nice-Sophia Antipolis, 660 Route des Lucioles, 06560, Valbonne, France
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Harleton E, Besana A, Chandra P, Danilo P, Rosen TS, Rosen MR, Argenziano M, Robinson RB, Feinmark SJ. TASK-1 current is inhibited by phosphorylation during human and canine chronic atrial fibrillation. Am J Physiol Heart Circ Physiol 2014; 308:H126-34. [PMID: 25437921 DOI: 10.1152/ajpheart.00614.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Atrial fibrillation (AF) is a common arrhythmia with significant morbidities and only partially adequate therapeutic options. AF is associated with atrial remodeling processes, including changes in the expression and function of ion channels and signaling pathways. TWIK protein-related acid-sensitive K+ channel (TASK)-1, a two-pore domain K+ channel, has been shown to contribute to action potential repolarization as well as to the maintenance of resting membrane potential in isolated myocytes, and TASK-1 inhibition has been associated with the induction of perioperative AF. However, the role of TASK-1 in chronic AF is unknown. The present study investigated the function, expression, and phosphorylation of TASK-1 in chronic AF in atrial tissue from chronically paced canines and in human subjects. TASK-1 current was present in atrial myocytes isolated from human and canine hearts in normal sinus rhythm but was absent in myocytes from humans with AF and in canines after the induction of AF by chronic tachypacing. The addition of phosphatase to the patch pipette rescued TASK-1 current from myocytes isolated from AF hearts, indicating that the change in current is phosphorylation dependent. Western blot analysis showed that total TASK-1 protein levels either did not change or increased slightly in AF, despite the absence of current. In studies of perioperative AF, we have shown that phosphorylation of TASK-1 at Thr383 inhibits the channel. However, phosphorylation at this site was unchanged in atrial tissue from humans with AF or in canines with chronic pacing-induced AF. We conclude that phosphorylation-dependent inhibition of TASK-1 is associated with AF, but the phosphorylation site responsible for this inhibition remains to be identified.
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Affiliation(s)
- Erin Harleton
- Department of Pharmacology, Columbia University Medical Center, New York, New York
| | - Alessandra Besana
- Department of Pharmacology, Columbia University Medical Center, New York, New York
| | - Parag Chandra
- Department of Pharmacology, Columbia University Medical Center, New York, New York
| | - Peter Danilo
- Department of Pharmacology, Columbia University Medical Center, New York, New York
| | - Tove S Rosen
- Department of Pediatrics, Columbia University Medical Center, New York, New York
| | - Michael R Rosen
- Department of Pharmacology, Columbia University Medical Center, New York, New York; Department of Pediatrics, Columbia University Medical Center, New York, New York
| | - Michael Argenziano
- Division of Cardiothoracic Surgery, Department of Surgery, Columbia University Medical Center, New York, New York; and
| | - Richard B Robinson
- Department of Pharmacology, Columbia University Medical Center, New York, New York
| | - Steven J Feinmark
- Department of Pharmacology, Columbia University Medical Center, New York, New York;
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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: 1.4] [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: 3.6] [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: 3.2] [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: 3.0] [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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Akar FG. A formidable "TASK": tipping the balance in favor of rhythm control for the management of atrial fibrillation. Heart Rhythm 2014; 11:1806-7. [PMID: 25041966 DOI: 10.1016/j.hrthm.2014.07.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Indexed: 10/25/2022]
Affiliation(s)
- Fadi G Akar
- Cardiovascular Institute, Ichan School of Medicine at Mount Sinai, New York, New York.
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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: 160] [Impact Index Per Article: 16.0] [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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Dev NB, Mir SA, Gayen JR, Siddiqui JA, Mustapic M, Vaingankar SM. Cardiac electrical activity in a genomically "humanized" chromogranin a monogenic mouse model with hyperadrenergic hypertension. J Cardiovasc Transl Res 2014; 7:483-493. [PMID: 24821335 DOI: 10.1007/s12265-014-9563-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 04/06/2014] [Indexed: 12/16/2022]
Abstract
The prohormone chromogranin A (CHGA) is ubiquitously found in vesicles of adrenal chromaffin cells and adrenergic neurons, and it is processed to the hypotensive hormone peptide catestatin (CST). Both CHGA and CST regulate blood pressure and cardiac function. This study addresses their role in cardiac electrical activity. We have generated two genomically "humanized" transgenic mouse strains (Tg31CHGA+/+; Chga-/- (HumCHGA31) and Tg19CHGA+/+; Chga-/- (HumCHGA19)) with varied CHGA expression and the ability to rescue the Chga-/- phenotype (hypertensive, hyperadrenergic with dilated cardiomyopathy). The normotensive HumCHGA31 mice express CHGA at levels comparable to wild-type. In contrast, the hypertensive HumCHGA19 mice have low levels of CHGA. EKG recordings revealed that the QT interval, R-amplitude, and QRS time-voltage integral are markedly longer in HumCHGA19 compared to wild-type and HumCHGA31 mice. These differences are accompanied by increased heart rate and QT variability, indicating that ventricular assault happens in a status of low levels of circulating CST.
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Affiliation(s)
- Nagendu B Dev
- Department of Medicine, University of California at San Diego, USA
| | - Saiful A Mir
- Department of Medicine, University of California at San Diego, USA
| | | | - Jawed A Siddiqui
- Department of Medicine, University of California at San Diego, USA
| | - Maja Mustapic
- Department of Medicine, University of California at San Diego, USA
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