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Narasimhan B, Gandhi K, Moras E, Wu L, Da Wariboko A, Aronow W. Experimental drugs for supraventricular tachycardia: an analysis of early phase clinical trials. Expert Opin Investig Drugs 2023; 32:825-838. [PMID: 37728554 DOI: 10.1080/13543784.2023.2259309] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 09/12/2023] [Indexed: 09/21/2023]
Abstract
INTRODUCTION Supraventricular tachycardias (SVT) are a diverse group of commonly encountered arrhythmias arising at or above the atrioventricular (AV) node. Conventional anti-arrhythmic medications are restricted by extensive side-effect profiles and limited efficacy. Catheter ablation has emerged as a first-line therapy for many arrhythmias but is not a suitable option for all patients. This has prompted the exploration of novel pharmacological approaches targeting specific molecular mechanisms of SVT. AREAS COVERED This review article aims to summarize recent advancements in pharmacological therapeutics for SVT and their clinical implications. The understanding of molecular mechanisms underlying these arrhythmias, particularly atrial fibrillation, has opened up new possibilities for targeted interventions. Beyond the manipulation of ion channels and membrane potentials, pharmacotherapy now focuses on upstream targets such as inflammation, oxidative stress, and structural remodeling. This review strives to provide a comprehensive overview of recent advancements in pharmacological therapeutics directed at the management of SVT. We begin by providing a brief summary of the mechanisms and management of commonly encountered SVT before delving into individual agents, which in turn are stratified based on their molecular treatment targets. EXPERT OPINION The evolving landscape of pharmacologic therapy offers hope for more personalized and tailored interventions in the management of SVT.
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Affiliation(s)
- Bharat Narasimhan
- DeBakey Cardiovascular Institute, Houston Methodist, Houston, TX, USA
| | - Kruti Gandhi
- Department of Internal Medicine, Icahn School of Medicine, Mount Sinai, New York, NY, USA
| | - Errol Moras
- Department of Internal Medicine, Icahn School of Medicine, Mount Sinai, New York, NY, USA
| | - Lingling Wu
- Department of Medicine, Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Akanibo Da Wariboko
- Department of Internal Medicine, Icahn School of Medicine, Mount Sinai, New York, NY, USA
| | - Wilbert Aronow
- Department of Cardiology, Westchester Medical Center, Valhalla, NY, USA
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2
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Lee DS, Kim TH, Park H, Kang TC. Deregulation of Astroglial TASK-1 K+ Channel Decreases the Responsiveness to Perampanel-Induced AMPA Receptor Inhibition in Chronic Epilepsy Rats. Int J Mol Sci 2023; 24:ijms24065491. [PMID: 36982567 PMCID: PMC10049714 DOI: 10.3390/ijms24065491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2023] [Revised: 03/06/2023] [Accepted: 03/10/2023] [Indexed: 03/17/2023] Open
Abstract
Tandem of P domains in a weak inwardly rectifying K+ channel (TWIK)-related acid sensitive K+-1 channel (TASK-1) is activated under extracellular alkaline conditions (pH 7.2–8.2), which are upregulated in astrocytes (particularly in the CA1 region) of the hippocampi of patients with temporal lobe epilepsy and chronic epilepsy rats. Perampanel (PER) is a non-competitive α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) antagonist used for the treatment of focal seizures and primary generalized tonic–clonic seizures. Since AMPAR activation leads to extracellular alkaline shifts, it is likely that the responsiveness to PER in the epileptic hippocampus may be relevant to astroglial TASK-1 regulation, which has been unreported. In the present study, we found that PER ameliorated astroglial TASK-1 upregulation in responders (whose seizure activities were responsive to PER), but not non-responders (whose seizure activities were not responsive to PER), in chronic epilepsy rats. ML365 (a selective TASK-1 inhibitor) diminished astroglial TASK-1 expression and seizure duration in non-responders to PER. ML365 co-treatment with PER decreased spontaneous seizure activities in non-responders to PER. These findings suggest that deregulation of astroglial TASK-1 upregulation may participate in the responsiveness to PER, and that this may be a potential target to improve the efficacies of PER.
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Affiliation(s)
- Duk-Shin Lee
- Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
| | - Tae-Hyun Kim
- Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
| | - Hana Park
- Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
| | - Tae-Cheon Kang
- Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Institute of Epilepsy Research, College of Medicine, Hallym University, Chuncheon 24252, Republic of Korea
- Correspondence: ; Tel.: +82-33-248-2524; Fax: +82-33-248-2525
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3
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Fan X, Lu Y, Du G, Liu J. Advances in the Understanding of Two-Pore Domain TASK Potassium Channels and Their Potential as Therapeutic Targets. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27238296. [PMID: 36500386 PMCID: PMC9736439 DOI: 10.3390/molecules27238296] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 11/09/2022] [Accepted: 11/15/2022] [Indexed: 11/29/2022]
Abstract
TWIK-related acid-sensitive K+ (TASK) channels, including TASK-1, TASK-3, and TASK-5, are important members of the two-pore domain potassium (K2P) channel family. TASK-5 is not functionally expressed in the recombinant system. TASK channels are very sensitive to changes in extracellular pH and are active during all membrane potential periods. They are similar to other K2P channels in that they can create and use background-leaked potassium currents to stabilize resting membrane conductance and repolarize the action potential of excitable cells. TASK channels are expressed in both the nervous system and peripheral tissues, including excitable and non-excitable cells, and are widely engaged in pathophysiological phenomena, such as respiratory stimulation, pulmonary hypertension, arrhythmia, aldosterone secretion, cancers, anesthesia, neurological disorders, glucose homeostasis, and visual sensitivity. Therefore, they are important targets for innovative drug development. In this review, we emphasized the recent advances in our understanding of the biophysical properties, gating profiles, and biological roles of TASK channels. Given the different localization ranges and biologically relevant functions of TASK-1 and TASK-3 channels, the development of compounds that selectively target TASK-1 and TASK-3 channels is also summarized based on data reported in the literature.
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Affiliation(s)
- Xueming Fan
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China
- Department of Anesthesiology, Guizhou Provincial People’s Hospital, Guiyang 550002, China
| | - Yongzhi Lu
- Guangdong Provincial Key Laboratory of Biocomputing, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510700, China
| | - Guizhi Du
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China
- Correspondence: (G.D.); (J.L.)
| | - Jin Liu
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Center of Translational Medicine of Anesthesiology, Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu 610041, China
- Correspondence: (G.D.); (J.L.)
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4
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Arévalo B, Bedoya M, Kiper AK, Vergara F, Ramírez D, Mazola Y, Bustos D, Zúñiga R, Cikutovic R, Cayo A, Rinné S, Ramirez-Apan MT, Sepúlveda FV, Cerda O, López-Collazo E, Decher N, Zúñiga L, Gutierrez M, González W. Selective TASK-1 Inhibitor with a Defined Structure–Activity Relationship Reduces Cancer Cell Proliferation and Viability. J Med Chem 2022; 65:15014-15027. [DOI: 10.1021/acs.jmedchem.1c00378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Bárbara Arévalo
- Centro de Estudios en Alimentos Procesados−CEAP, Conicyt, Programa Regional R19A10001, Gore Maule, 3460000 Talca, Chile
| | - Mauricio Bedoya
- Centro de Investigación de Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, 3460000 Talca, Chile
- Laboratorio de Bioinformática y Química Computacional, Departamento de Medicina Traslacional, Facultad de Medicina, Universidad Católica del Maule, 3480094 Talca, Chile
| | - Aytug K. Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 1-2, 35037 Marburg, Germany
| | - Fernando Vergara
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, 1 Poniente No. 1141, 3460000 Talca, Chile
| | - David Ramírez
- Departamento de Farmacología, Facultad de Ciencias Biológicas, Universidad de Concepción, 4030000 Concepción, Chile
| | - Yuliet Mazola
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, 1 Poniente No. 1141, 3460000 Talca, Chile
| | - Daniel Bustos
- Centro de Investigación de Estudios Avanzados del Maule (CIEAM), Vicerrectoría de Investigación y Postgrado, Universidad Católica del Maule, 3460000 Talca, Chile
- Laboratorio de Bioinformática y Química Computacional (LBQC), Escuela de Química y Farmacia, Facultad de Medicina, Universidad Católica del Maule, 3460000 Talca, Chile
| | - Rafael Zúñiga
- Centro de Nanomedicina, Diagnóstico y Desarrollo de Fármacos (ND3), Laboratorio de Fisiología Molecular, Escuela de Medicina, Universidad de Talca, Casilla, 3460000 Talca, Chile
- Instituto de Investigación Interdisciplinaria, Vicerrectoría Académica, Universidad de Talca, 3460000 Talca, Chile
| | - Rocio Cikutovic
- Centro de Nanomedicina, Diagnóstico y Desarrollo de Fármacos (ND3), Laboratorio de Fisiología Molecular, Escuela de Medicina, Universidad de Talca, Casilla, 3460000 Talca, Chile
| | - Angel Cayo
- Centro de Nanomedicina, Diagnóstico y Desarrollo de Fármacos (ND3), Laboratorio de Fisiología Molecular, Escuela de Medicina, Universidad de Talca, Casilla, 3460000 Talca, Chile
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 1-2, 35037 Marburg, Germany
| | - M. Teresa Ramirez-Apan
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, 04510, Coyoacán, 04510 México, DF, México
| | - Francisco V. Sepúlveda
- Centro de Estudios Científicos (CECs), 5110466 Valdivia, Chile
- Facultad de Medicina y Ciencia, Universidad San Sebastián, 5110466 Valdivia, Chile
| | - Oscar Cerda
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, 8380453 Santiago, Chile
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Facultad de Medicina, Universidad de Chile, 8380453 Santiago, Chile
| | - Eduardo López-Collazo
- The Innate Immune Response Group and Tumor Immunology Laboratory, IdiPAZ, La Paz University Hospital, 8046 Madrid, Spain
| | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 1-2, 35037 Marburg, Germany
- Marburg Center for Mind, Brain and Behavior−MCMBB, Philipps-University Marburg, 35037 Marburg, Germany
| | - Leandro Zúñiga
- Centro de Nanomedicina, Diagnóstico y Desarrollo de Fármacos (ND3), Laboratorio de Fisiología Molecular, Escuela de Medicina, Universidad de Talca, Casilla, 3460000 Talca, Chile
| | - Margarita Gutierrez
- Laboratorio de Síntesis y Actividad Biológica, Instituto de Química de Recursos Naturales, Universidad de Talca, 1 poniente No. 1141, 3460000 Talca, Chile
| | - Wendy González
- Centro de Bioinformática, Simulación y Modelado (CBSM), Facultad de Ingeniería, Universidad de Talca, 1 Poniente No. 1141, 3460000 Talca, Chile
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Talca, 1 Poniente No. 1141, 3460000 Talca, Chile
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Redel-Traub G, Sampson KJ, Kass RS, Bohnen MS. Potassium Channels as Therapeutic Targets in Pulmonary Arterial Hypertension. Biomolecules 2022; 12:1341. [PMID: 36291551 PMCID: PMC9599705 DOI: 10.3390/biom12101341] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 09/16/2022] [Accepted: 09/18/2022] [Indexed: 12/08/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is a devastating disease with high morbidity and mortality. Deleterious remodeling in the pulmonary arterial system leads to irreversible arterial constriction and elevated pulmonary arterial pressures, right heart failure, and eventually death. The difficulty in treating PAH stems in part from the complex nature of disease pathogenesis, with several signaling compounds known to be involved (e.g., endothelin-1, prostacyclins) which are indeed targets of PAH therapy. Over the last decade, potassium channelopathies were established as novel causes of PAH. More specifically, loss-of-function mutations in the KCNK3 gene that encodes the two-pore-domain potassium channel KCNK3 (or TASK-1) and loss-of-function mutations in the ABCC8 gene that encodes a key subunit, SUR1, of the ATP-sensitive potassium channel (KATP) were established as the first two potassium channelopathies in human cohorts with pulmonary arterial hypertension. Moreover, voltage-gated potassium channels (Kv) represent a third family of potassium channels with genetic changes observed in association with PAH. While other ion channel genes have since been reported in association with PAH, this review focuses on KCNK3, KATP, and Kv potassium channels as promising therapeutic targets in PAH, with recent experimental pharmacologic discoveries significantly advancing the field.
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Affiliation(s)
- Gabriel Redel-Traub
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Kevin J. Sampson
- Department of Molecular Pharmacology and Therapeutics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Robert S. Kass
- Department of Molecular Pharmacology and Therapeutics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Michael S. Bohnen
- Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
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6
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Wu XY, Lv JY, Zhang SQ, Yi X, Xu ZW, Zhi YX, Zhao BX, Pang JX, Yung KKL, Liu SW, Zhou PZ. ML365 inhibits TWIK2 channel to block ATP-induced NLRP3 inflammasome. Acta Pharmacol Sin 2022; 43:992-1000. [PMID: 34341510 DOI: 10.1038/s41401-021-00739-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 06/30/2021] [Indexed: 02/06/2023] Open
Abstract
Dysregulation of NLRP3 inflammasome results in uncontrolled inflammation, which participates in various chronic diseases. TWIK2 potassium channel mediates potassium efflux that has been reported to be an essential upstream mechanism for ATP-induced NLRP3 inflammasome activation. Thus, TWIK2 potassium channel could be a potential drug target for NLRP3-related inflammatory diseases. In the present study we investigated the effects of known K2P channel modulators on TWIK2 channel expressed in a heterologous system. In order to increase plasma membrane expression and thus TWIK2 currents, a mutant channel with three mutations (TWIK2I289A/L290A/Y308A) in the C-terminus was expressed in COS-7 cells. TWIK2 currents were assessed using whole-cell voltage-clamp recording. Among 6 known K2P channel modulators tested (DCPIB, quinine, fluoxetine, ML365, ML335, and TKDC), ML365 was the most potent TWIK2 channel blocker with an IC50 value of 4.07 ± 1.5 μM. Furthermore, ML365 selectively inhibited TWIK2 without affecting TWIK1 or THIK1 channels. We showed that ML365 (1, 5 μM) concentration-dependently inhibited ATP-induced NLRP3 inflammasome activation in LPS-primed murine BMDMs, whereas it did not affect nigericin-induced NLRP3, or non-canonical, AIM2 and NLRC4 inflammasomes activation. Knockdown of TWIK2 significantly impaired the inhibitory effect of ML365 on ATP-induced NLRP3 inflammasome activation. Moreover, we demonstrated that pre-administration of ML365 (1, 10, 25 mg/kg, ip) dose-dependently ameliorated LPS-induced endotoxic shock in mice. In a preliminary pharmacokinetic study conducted in rats, ML365 showed good absolute oral bioavailability with F value of 22.49%. In conclusion, ML365 provides a structural reference for future design of selective TWIK2 channel inhibitors in treating related inflammatory diseases.
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7
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Kim JE, Kang TC. Blockade of TASK-1 Channel Improves the Efficacy of Levetiracetam in Chronically Epileptic Rats. Biomedicines 2022; 10:biomedicines10040787. [PMID: 35453538 PMCID: PMC9030960 DOI: 10.3390/biomedicines10040787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/21/2022] [Accepted: 03/26/2022] [Indexed: 11/29/2022] Open
Abstract
Tandem of P domains in a weak inwardly rectifying K+ channel (TWIK)-related acid sensitive K+-1 channel (TASK-1) is an outwardly rectifying K+ channel that acts in response to extracellular pH. TASK-1 is upregulated in the astrocytes (particularly in the CA1 region) of the hippocampi of patients with temporal lobe epilepsy and chronically epilepsy rats. Since levetiracetam (LEV) is an effective inhibitor for carbonic anhydrase, which has a pivotal role in buffering of extracellular pH, it is likely that the anti-epileptic action of LEV may be relevant to TASK-1 inhibition, which remains to be elusive. In the present study, we found that LEV diminished the upregulated TASK-1 expression in the CA1 astrocytes of responders (whose seizure activities were responsive to LEV), but not non-responders (whose seizure activities were not controlled by LEV) in chronically epileptic rats. ML365 (a selective TASK-1 inhibitor) only reduced seizure duration in LEV non-responders, concomitant with astroglial TASK-1 downregulation. Furthermore, ML365 co-treatment with LEV decreased the duration, frequency and severity of spontaneous seizures in non-responders to LEV. To the best of our knowledge, our findings suggest, for the first time, that the up-regulation of TASK-1 expression in CA1 astrocytes may be involved in refractory seizures in response to LEV. This may be a potential target to improve responsiveness to LEV.
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Affiliation(s)
| | - Tae-Cheon Kang
- Correspondence: ; Tel.: +82-33-248-2524; Fax: +82-33-248-2525
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8
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McCoull D, Veale EL, Walsh Y, Byrom L, Avkiran T, Large JM, Vaitone E, Gaffey F, Jerman J, Mathie A, Wright PD. Aprepitant is a novel, selective activator of the K2P channel TRAAK. Biochem Biophys Res Commun 2021; 588:41-46. [PMID: 34942533 DOI: 10.1016/j.bbrc.2021.12.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 12/12/2021] [Indexed: 11/02/2022]
Abstract
TRAAK (KCNK4, K2P4.1) is a mechanosensitive two-pore domain potassium (K2P) channel. Due to its expression within sensory neurons and genetic link to neuropathic pain it represents a promising potential target for novel analgesics. In common with many other channels in the wider K2P sub-family, there remains a paucity of small molecule pharmacological tools. Specifically, there is a lack of molecules selective for TRAAK over the other members of the TREK subfamily of K2P channels. We developed a thallium flux assay to allow high throughput screening of compounds and facilitate the identification of novel TRAAK activators. Using a library of ∼1200 drug like molecules we identified Aprepitant as a small molecule activator of TRAAK. Aprepitant is an NK-1 antagonist used to treat nausea and vomiting. Close structural analogues of Aprepitant and a range of NK-1 antagonists were also selected or designed for purchase or brief chemical synthesis and screened for their ability to activate TRAAK. Electrophysiology experiments confirmed that Aprepitant activates both the 'long' and 'short' transcript variants of TRAAK. We also demonstrated that Aprepitant is selective and does not activate other members of the K2P superfamily. This work describes the development of a high throughput assay to identify potential TRAAK activators and subsequent identification and confirmation of the novel TRAAK activator Aprepitant. This discovery identifies a useful tool compound which can be used to further probe the function of TRAAK K2P channels.
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Affiliation(s)
- D McCoull
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK.
| | - E L Veale
- Medway School of Pharmacy, University of Greenwich and University of Kent, Anson Building, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
| | - Y Walsh
- Medway School of Pharmacy, University of Greenwich and University of Kent, Anson Building, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK
| | - L Byrom
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - T Avkiran
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - J M Large
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - E Vaitone
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - F Gaffey
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - J Jerman
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
| | - A Mathie
- Medway School of Pharmacy, University of Greenwich and University of Kent, Anson Building, Central Avenue, Chatham Maritime, Kent, ME4 4TB, UK; School of Engineering, Arts, Science and Technology, University of Suffolk, Ipswich, IP4 1QJ, UK
| | - P D Wright
- LifeArc, Accelerator Building, Open Innovation Campus, Stevenage, SG1 2FX, UK
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9
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Gurges P, Liu H, Horner RL. Modulation of TASK-1/3 channels at the hypoglossal motoneuron pool and effects on tongue motor output and responses to excitatory inputs in vivo: implications for strategies for obstructive sleep apnea pharmacotherapy. Sleep 2021; 44:5880005. [PMID: 32745213 PMCID: PMC7819847 DOI: 10.1093/sleep/zsaa144] [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: 04/02/2020] [Revised: 06/29/2020] [Indexed: 12/25/2022] Open
Abstract
Obstructive sleep apnea (OSA) occurs exclusively during sleep due to reduced tongue motor activity. Withdrawal of excitatory inputs to the hypoglossal motor nucleus (HMN) from wake to sleep contributes to this reduced activity. Several awake-active neurotransmitters with inputs to the HMN (e.g. serotonin [5-HT]) inhibit K+ leak mediated by TASK-1/3 channels on hypoglossal motoneurons, leading to increased neuronal activity in vitro. We hypothesize that TASK channel inhibition at the HMN will increase tongue muscle activity in vivo and modulate responses to 5-HT. We first microperfused the HMN of anesthetized rats with TASK channel inhibitors: doxapram (75 μM, n = 9), A1899 (25 μM, n = 9), ML365 (25 μM, n = 9), acidified artificial cerebrospinal fluid (ACSF, pH = 6.25, n = 9); and a TASK channel activator terbinafine (50 μM, n = 9); all with and without co-applied 5-HT (10 mM). 5-HT alone at the HMN increased tongue motor activity (202.8% ± 45.9%, p < 0.001). However, neither the TASK channel inhibitors, nor activator, at the HMN changed baseline tongue activity (p > 0.716) or responses to 5-HT (p > 0.127). Tonic tongue motor responses to 5-HT at the HMN were also not different (p > 0.05) between ChAT-Cre:TASKf/f mice (n = 8) lacking TASK-1/3 channels on cholinergic neurons versus controls (n = 10). In freely behaving rats (n = 9), microperfusion of A1899 into the HMN increased within-breath phasic tongue motor activity in wakefulness only (p = 0.005) but not sleep, with no effects on tonic activity across all sleep-wake states. Together, the findings suggest robust maintenance of tongue motor activity despite various strategies for TASK channel manipulation targeting the HMN in vivo, and thus currently do not support this target and direction for potential OSA pharmacotherapy.
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Affiliation(s)
- Patrick Gurges
- Institute of Medical Science, University of Toronto, Toronto, Canada
| | - Hattie Liu
- Department of Medicine, University of Toronto, Toronto, Canada
| | - Richard L Horner
- Department of Medicine, University of Toronto, Toronto, Canada.,Department of Physiology, University of Toronto, Toronto, Canada
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10
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Natale AM, Deal PE, Minor DL. Structural Insights into the Mechanisms and Pharmacology of K 2P Potassium Channels. J Mol Biol 2021; 433:166995. [PMID: 33887333 PMCID: PMC8436263 DOI: 10.1016/j.jmb.2021.166995] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/08/2021] [Accepted: 04/09/2021] [Indexed: 01/10/2023]
Abstract
Leak currents, defined as voltage and time independent flows of ions across cell membranes, are central to cellular electrical excitability control. The K2P (KCNK) potassium channel class comprises an ion channel family that produces potassium leak currents that oppose excitation and stabilize the resting membrane potential in cells in the brain, cardiovascular system, immune system, and sensory organs. Due to their widespread tissue distribution, K2Ps contribute to many physiological and pathophysiological processes including anesthesia, pain, arrythmias, ischemia, hypertension, migraine, intraocular pressure regulation, and lung injury responses. Structural studies of six homomeric K2Ps have established the basic architecture of this channel family, revealed key moving parts involved in K2P function, uncovered the importance of asymmetric pinching and dilation motions in the K2P selectivity filter (SF) C-type gate, and defined two K2P structural classes based on the absence or presence of an intracellular gate. Further, a series of structures characterizing K2P:modulator interactions have revealed a striking polysite pharmacology housed within a relatively modestly sized (~70 kDa) channel. Binding sites for small molecules or lipids that control channel function are found at every layer of the channel structure, starting from its extracellular side through the portion that interacts with the membrane bilayer inner leaflet. This framework provides the basis for understanding how gating cues sensed by different channel parts control function and how small molecules and lipids modulate K2P activity. Such knowledge should catalyze development of new K2P modulators to probe function and treat a wide range of disorders.
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Affiliation(s)
- Andrew M Natale
- Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
| | - Parker E Deal
- Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
| | - Daniel L Minor
- Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA; Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; California Institute for Quantitative Biomedical Research, University of California, San Francisco, CA 94158, USA; Kavli Institute for Fundamental Neuroscience University of California, San Francisco, CA 94158, USA; Molecular Biophysics and Integrated Bio-imaging Division Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
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11
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Giannoni-Guzmán MA, Kamitakahara A, Magalong V, Levitt P, McMahon DG. Circadian photoperiod alters TREK-1 channel function and expression in dorsal raphe serotonergic neurons via melatonin receptor 1 signaling. J Pineal Res 2021; 70:e12705. [PMID: 33210730 PMCID: PMC8496951 DOI: 10.1111/jpi.12705] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/05/2020] [Accepted: 11/09/2020] [Indexed: 12/11/2022]
Abstract
Seasonal day length has been linked to the prevalence of mood disorders, and however, the mechanisms underlying this relationship remain unknown. Previous work in our laboratory has shown that developmental exposure to seasonal photoperiods has enduring effects on the activity of mouse dorsal raphe serotonergic neurons, their intrinsic electrical properties, as well as on depression and anxiety-related behaviors. Here we focus on the possible ionic mechanisms that underlie the observed programming of the electrophysiological properties of serotonin neurons, focusing on the twin-pore K + channels TREK-1 and TASK-1 that set resting membrane potential and regulate excitability. Pharmacological inhibition of TREK-1 significantly increased spike frequency in Short and Equinox photoperiods, but did not further elevate the firing rate in slices from Long photoperiod mice, suggesting that TREK-1 function is reduced in Long photoperiods. In contrast, inhibition of TASK-1 resulted in increases in firing rates across all photoperiods, suggesting that it contributes to setting excitability, but is not regulated by photoperiod. We then quantified Kcnk2 mRNA levels specifically in dorsal raphe 5-HT neurons using triple-label RNAscope. We found that Long photoperiod significantly reduced levels of Kcnk2 in serotonin neurons co-expressing Tph2, and Pet-1. Photoperiodic effects on the function and expression of TREK-1 were blocked in melatonin 1 receptor knockout (MT-1KO) mice, consistent with previous findings that MT-1 signaling is necessary for photoperiodic programming of dorsal raphe 5-HT neurons. Taken together these results indicate that photoperiodic regulation of TREK-1 expression and function plays a key role in photoperiodic programming the excitability of dorsal raphe 5-HT neurons.
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Affiliation(s)
| | - Anna Kamitakahara
- Department of Pediatrics and Program in Developmental Neuroscience and Neurogenetics, Keck School of Medicine, The Saban Research Institute, Children’s Hospital Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Valerie Magalong
- Department of Pediatrics and Program in Developmental Neuroscience and Neurogenetics, Keck School of Medicine, The Saban Research Institute, Children’s Hospital Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Pat Levitt
- Department of Pediatrics and Program in Developmental Neuroscience and Neurogenetics, Keck School of Medicine, The Saban Research Institute, Children’s Hospital Los Angeles, University of Southern California, Los Angeles, CA, USA
| | - Douglas G. McMahon
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, USA
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12
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Le Ribeuz H, Capuano V, Girerd B, Humbert M, Montani D, Antigny F. Implication of Potassium Channels in the Pathophysiology of Pulmonary Arterial Hypertension. Biomolecules 2020; 10:biom10091261. [PMID: 32882918 PMCID: PMC7564204 DOI: 10.3390/biom10091261] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 02/06/2023] Open
Abstract
Pulmonary arterial hypertension (PAH) is a rare and severe cardiopulmonary disease without curative treatments. PAH is a multifactorial disease that involves genetic predisposition, epigenetic factors, and environmental factors (drugs, toxins, viruses, hypoxia, and inflammation), which contribute to the initiation or development of irreversible remodeling of the pulmonary vessels. The recent identification of loss-of-function mutations in KCNK3 (KCNK3 or TASK-1) and ABCC8 (SUR1), or gain-of-function mutations in ABCC9 (SUR2), as well as polymorphisms in KCNA5 (Kv1.5), which encode two potassium (K+) channels and two K+ channel regulatory subunits, has revived the interest of ion channels in PAH. This review focuses on KCNK3, SUR1, SUR2, and Kv1.5 channels in pulmonary vasculature and discusses their pathophysiological contribution to and therapeutic potential in PAH.
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Affiliation(s)
- Hélène Le Ribeuz
- Faculté de Médecine, Université Paris-Saclay, 94270 Le Kremlin-Bicêtre, France; (H.L.R.); (V.C.); (B.G.); (M.H.); (D.M.)
- INSERM UMR_S 999, Hypertension pulmonaire, Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, 92350 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, 94270 Le Kremlin-Bicêtre, France
| | - Véronique Capuano
- Faculté de Médecine, Université Paris-Saclay, 94270 Le Kremlin-Bicêtre, France; (H.L.R.); (V.C.); (B.G.); (M.H.); (D.M.)
- INSERM UMR_S 999, Hypertension pulmonaire, Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, 92350 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, 94270 Le Kremlin-Bicêtre, France
| | - Barbara Girerd
- Faculté de Médecine, Université Paris-Saclay, 94270 Le Kremlin-Bicêtre, France; (H.L.R.); (V.C.); (B.G.); (M.H.); (D.M.)
- INSERM UMR_S 999, Hypertension pulmonaire, Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, 92350 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, 94270 Le Kremlin-Bicêtre, France
| | - Marc Humbert
- Faculté de Médecine, Université Paris-Saclay, 94270 Le Kremlin-Bicêtre, France; (H.L.R.); (V.C.); (B.G.); (M.H.); (D.M.)
- INSERM UMR_S 999, Hypertension pulmonaire, Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, 92350 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, 94270 Le Kremlin-Bicêtre, France
| | - David Montani
- Faculté de Médecine, Université Paris-Saclay, 94270 Le Kremlin-Bicêtre, France; (H.L.R.); (V.C.); (B.G.); (M.H.); (D.M.)
- INSERM UMR_S 999, Hypertension pulmonaire, Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, 92350 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, 94270 Le Kremlin-Bicêtre, France
| | - Fabrice Antigny
- Faculté de Médecine, Université Paris-Saclay, 94270 Le Kremlin-Bicêtre, France; (H.L.R.); (V.C.); (B.G.); (M.H.); (D.M.)
- INSERM UMR_S 999, Hypertension pulmonaire, Physiopathologie et Innovation Thérapeutique, Hôpital Marie Lannelongue, 92350 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, 94270 Le Kremlin-Bicêtre, France
- Correspondence: or ; Tel.: +33-1-40-94-22-99
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Mathie A, Veale EL, Cunningham KP, Holden RG, Wright PD. Two-Pore Domain Potassium Channels as Drug Targets: Anesthesia and Beyond. Annu Rev Pharmacol Toxicol 2020; 61:401-420. [PMID: 32679007 DOI: 10.1146/annurev-pharmtox-030920-111536] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Two-pore domain potassium (K2P) channels stabilize the resting membrane potential of both excitable and nonexcitable cells and, as such, are important regulators of cell activity. There are many conditions where pharmacological regulation of K2P channel activity would be of therapeutic benefit, including, but not limited to, atrial fibrillation, respiratory depression, pulmonary hypertension, neuropathic pain, migraine, depression, and some forms of cancer. Up until now, few if any selective pharmacological regulators of K2P channels have been available. However, recent publications of solved structures with small-molecule activators and inhibitors bound to TREK-1, TREK-2, and TASK-1 K2P channels have given insight into the pharmacophore requirements for compound binding to these sites. Together with the increasing availability of a number of novel, active, small-molecule compounds from K2P channel screening programs, these advances have opened up the possibility of rational activator and inhibitor design to selectively target K2P channels.
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Affiliation(s)
- Alistair Mathie
- Medway School of Pharmacy, University of Greenwich and University of Kent, Kent ME4 4TB, United Kingdom;
| | - Emma L Veale
- Medway School of Pharmacy, University of Greenwich and University of Kent, Kent ME4 4TB, United Kingdom;
| | - Kevin P Cunningham
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom
| | - Robyn G Holden
- Medway School of Pharmacy, University of Greenwich and University of Kent, Kent ME4 4TB, United Kingdom;
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14
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Withaferin A suppresses breast cancer cell proliferation by inhibition of the two-pore domain potassium (K2P9) channel TASK-3. Biomed Pharmacother 2020; 129:110383. [PMID: 32563149 DOI: 10.1016/j.biopha.2020.110383] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 05/26/2020] [Accepted: 06/07/2020] [Indexed: 12/30/2022] Open
Abstract
Withaferin A (WFA), a C5,C6-epoxy steroidal lactone isolated from the medicinal plant Withania somnifera (L.) Dunal, inhibits growth of tumor cells in different cancer types. However, the mechanisms underlying the effect of WFA on tumor cells are not fully understood. In the present study, we evaluated the blockade of TASK-3 channels by WFA in TASK-3-expressing HEK-293 cells. Explore if the WFA-mediated TASK-3 blockade can be used as a pharmacological tool to decrease the cell viability in cancer cells. A combination of functional experiments (patch-clamp, gene downregulation, overexpression and pharmacological inhibition) and molecular docking analysis were used to get insights into the mechanism by which the inhibition of TASK-3 by WFA affects the growth and viability of cancer cells. Withaferin A was found to inhibit the activity of TASK-3 channels. The inhibitory effect of Withaferin A on TASK-3 potassium currents was dose-dependent and independent of voltage. Molecular modeling studies identified putative WFA-binding sites in TASK-3 channel involved the channel blockade. In agreements with the molecular modeling predictions, mutation of residues F125 to A (F125A), L197 to V (L197 V) and the double mutant F125A-L197 V markedly decreased the WFA-induced inhibition of TASK-3. Finally, the cytotoxic effect of WFA was tested in MDA-MB-231 human breast cancer cells transfected with TASK-3 or shRNA that decreases TASK-3 expression. Together, our results show that the cytotoxic effect of WFA on fully transformed MDA-MB-231 cells depends on the expression of TASK-3. Herein, we also provide insights into the mechanism of TASK-3 inhibition by WFA.
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15
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García G, Noriega-Navarro R, Martínez-Rojas VA, Gutiérrez-Lara EJ, Oviedo N, Murbartián J. Spinal TASK-1 and TASK-3 modulate inflammatory and neuropathic pain. Eur J Pharmacol 2019; 862:172631. [DOI: 10.1016/j.ejphar.2019.172631] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/09/2019] [Accepted: 08/27/2019] [Indexed: 12/13/2022]
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Bedoya M, Rinné S, Kiper AK, Decher N, González W, Ramírez D. TASK Channels Pharmacology: New Challenges in Drug Design. J Med Chem 2019; 62:10044-10058. [PMID: 31260312 DOI: 10.1021/acs.jmedchem.9b00248] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Rational drug design targeting ion channels is an exciting and always evolving research field. New medicinal chemistry strategies are being implemented to explore the wild chemical space and unravel the molecular basis of the ion channels modulators binding mechanisms. TASK channels belong to the two-pore domain potassium channel family and are modulated by extracellular acidosis. They are extensively distributed along the cardiovascular and central nervous systems, and their expression is up- and downregulated in different cancer types, which makes them an attractive therapeutic target. However, TASK channels remain unexplored, and drugs designed to target these channels are poorly selective. Here, we review TASK channels properties and their known blockers and activators, considering the new challenges in ion channels drug design and focusing on the implementation of computational methodologies in the drug discovery process.
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Affiliation(s)
- Mauricio Bedoya
- Centro de Bioinformática y Simulación Molecular (CBSM) , Universidad de Talca , 1 Poniente No. 1141 , 3460000 Talca , Chile
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior, MCMBB , Philipps-University of Marburg , Deutschhausstraße 2 , Marburg 35037 , Germany
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior, MCMBB , Philipps-University of Marburg , Deutschhausstraße 2 , Marburg 35037 , Germany
| | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology and Marburg Center for Mind, Brain and Behavior, MCMBB , Philipps-University of Marburg , Deutschhausstraße 2 , Marburg 35037 , Germany
| | - Wendy González
- Centro de Bioinformática y Simulación Molecular (CBSM) , Universidad de Talca , 1 Poniente No. 1141 , 3460000 Talca , Chile.,Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD) , Universidad de Talca , 1 Poniente No. 1141 , 3460000 Talca , Chile
| | - David Ramírez
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud , Universidad Autónoma de Chile , El Llano Subercaseaux 2801, Piso 6 , 8900000 Santiago , Chile
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17
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Şterbuleac D. Molecular determinants of chemical modulation of two-pore domain potassium channels. Chem Biol Drug Des 2019; 94:1596-1614. [PMID: 31124599 DOI: 10.1111/cbdd.13571] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/29/2019] [Accepted: 05/05/2019] [Indexed: 12/16/2022]
Abstract
The K+ ion channels comprising the two-pore domain (K2P) family have specific biophysical roles in generating the critical regulatory K+ current. Ion flow through K2P channels and, implicitly, channel regulation is mediated by diverse metabolic and physical inputs such as mechanical stimulation, interaction with lipids or endogenous regulators, intra- or extracellular pH, and phosphorylation, while their function can be finely tuned by chemical compounds. In the latter category, some drug-channel interactions can lead to side effects or have clinical action, while identifying novel chemical modulators of K2Ps is an area of intense research. Due to their cellular and therapeutic importance, much attention was turned to these channels in recent years and several experimental approaches have pinpointed the molecular determinants of K2P chemical modulation. Given their unique structural features and properties, chemical modulators act on K2P channels in multiple and diverse ways. In this review, the particularities of K2P modulation by chemical compounds, such as binding modality, affinity, or position, are identified, synthesized, and linked to structural and functional properties in order to refer to how activators and blockers modify channel function and vice versa, focusing on specificity related to protein structure (and its modification) and cross-linking information among different subfamilies.
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Affiliation(s)
- Daniel Şterbuleac
- Doctoral School of Biology, Faculty of Biology, "Alexandru Ioan Cuza" University of Iasi, Iasi, Romania
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18
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Ramírez D, Bedoya M, Kiper AK, Rinné S, Morales-Navarro S, Hernández-Rodríguez EW, Sepúlveda FV, Decher N, González W. Structure/Activity Analysis of TASK-3 Channel Antagonists Based on a 5,6,7,8 tetrahydropyrido[4,3-d]pyrimidine. Int J Mol Sci 2019; 20:ijms20092252. [PMID: 31067753 PMCID: PMC6539479 DOI: 10.3390/ijms20092252] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/18/2019] [Accepted: 04/20/2019] [Indexed: 11/16/2022] Open
Abstract
TASK-3 potassium (K+) channels are highly expressed in the central nervous system, regulating the membrane potential of excitable cells. TASK-3 is involved in neurotransmitter action and has been identified as an oncogenic K+ channel. For this reason, the understanding of the action mechanism of pharmacological modulators of these channels is essential to obtain new therapeutic strategies. In this study we describe the binding mode of the potent antagonist PK-THPP into the TASK-3 channel. PK-THPP blocks TASK-1, the closest relative channel of TASK-3, with almost nine-times less potency. Our results confirm that the binding is influenced by the fenestrations state of TASK-3 channels and occurs when they are open. The binding is mainly governed by hydrophobic contacts between the blocker and the residues of the binding site. These interactions occur not only for PK-THPP, but also for the antagonist series based on 5,6,7,8 tetrahydropyrido[4,3-d]pyrimidine scaffold (THPP series). However, the marked difference in the potency of THPP series compounds such as 20b, 21, 22 and 23 (PK-THPP) respect to compounds such as 17b, inhibiting TASK-3 channels in the micromolar range is due to the presence of a hydrogen bond acceptor group that can establish interactions with the threonines of the selectivity filter.
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Affiliation(s)
- David Ramírez
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile. El Llano Subercaseaux 2801-Piso 6, 7500912 Santiago, Chile.
| | - Mauricio Bedoya
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca. 1 Poniente No. 1141, 3460000 Talca, Chile.
| | - Aytug K Kiper
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 2, 35037 Marburg, Germany.
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 2, 35037 Marburg, Germany.
| | - Samuel Morales-Navarro
- Bachillerato en Ciencias, Facultad de Ciencias, Universidad Santo Tomás, Av. Circunvalación Poniente #1855, 3460000 Talca, Chile.
| | - Erix W Hernández-Rodríguez
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca. 1 Poniente No. 1141, 3460000 Talca, Chile.
- Escuela de Química y Farmacia. Facultad de Medicina. Universidad Católica del Maule, 3460000 Talca, Chile.
| | | | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology, Philipps-University of Marburg, Deutschhausstraße 2, 35037 Marburg, Germany.
| | - Wendy González
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca. 1 Poniente No. 1141, 3460000 Talca, Chile.
- Millennium Nucleus of Ion Channels-Associated Diseases (MiNICAD), Universidad de Talca, 3460000 Talca, Chile.
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Peyronnet R, Ravens U. Atria-selective antiarrhythmic drugs in need of alliance partners. Pharmacol Res 2019; 145:104262. [PMID: 31059791 DOI: 10.1016/j.phrs.2019.104262] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/30/2019] [Accepted: 05/03/2019] [Indexed: 12/15/2022]
Abstract
Atria-selective antiarrhythmic drugs in need of alliance partners. Guideline-based treatment of atrial fibrillation (AF) comprises prevention of thromboembolism and stroke, as well as antiarrhythmic therapy by drugs, electrical rhythm conversion, ablation and surgical procedures. Conventional antiarrhythmic drugs are burdened with unwanted side effects including a propensity of triggering life-threatening ventricular fibrillation. In order to solve this therapeutic dilemma, 'atria-selective' antiarrhythmic drugs have been developed for the treatment of supraventricular arrhythmias. These drugs are designed to aim at atrial targets, taking advantage of differences in atrial and ventricular ion channel expression and function. However it is not clear, whether such drugs are sufficiently antiarrhythmic or whether they are in need of an alliance partner for clinical efficacy. Atria-selective Na+ channel blockers display fast dissociation kinetics and high binding affinity to inactivated channels. Compounds targeting atria-selective K+ channels include blockers of ultra rapid delayed rectifier (Kv1.5) or acetylcholine-activated inward rectifier K+ channels (Kir3.x), inward rectifying K+ channels (Kir2.x), Ca2+-activated K+ channels of small conductance (SK), weakly rectifying two-pore domain K+ channels (K2P), and transient receptor potential channels (TRP). Despite good antiarrhythmic data from in-vitro and animal model experiments, clinical efficacy of atria-selective antiarrhythmic drugs remains to be demonstrated. In the present review we will briefly summarize the novel compounds and their proposed antiarrhythmic action. In addition, we will discuss the evidence for putative improvement of antiarrhythmic efficacy and potency by addressing multiple pathophysiologically relevant targets as possible alliance partners.
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Affiliation(s)
- Rémi Peyronnet
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg Bad Krozingen, Medical Center, University of Freiburg, Freiburg, Germany; Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ursula Ravens
- Institute for Experimental Cardiovascular Medicine, University Heart Center Freiburg Bad Krozingen, Medical Center, University of Freiburg, Freiburg, Germany; Institute of Physiology, Medical Faculty TU Dresden, Dresden, Germany.
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20
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Neurokinin-3 receptor activation selectively prolongs atrial refractoriness by inhibition of a background K + channel. Nat Commun 2018; 9:4357. [PMID: 30341287 PMCID: PMC6195571 DOI: 10.1038/s41467-018-06530-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 09/07/2018] [Indexed: 11/29/2022] Open
Abstract
The cardiac autonomic nervous system (ANS) controls normal atrial electrical function. The cardiac ANS produces various neuropeptides, among which the neurokinins, whose actions on atrial electrophysiology are largely unknown. We here demonstrate that the neurokinin substance-P (Sub-P) activates a neurokinin-3 receptor (NK-3R) in rabbit, prolonging action potential (AP) duration through inhibition of a background potassium current. In contrast, ventricular AP duration was unaffected by NK-3R activation. NK-3R stimulation lengthened atrial repolarization in intact rabbit hearts and consequently suppressed arrhythmia duration and occurrence in a rabbit isolated heart model of atrial fibrillation (AF). In human atrial appendages, the phenomenon of NK-3R mediated lengthening of atrial repolarization was also observed. Our findings thus uncover a pathway to selectively modulate atrial AP duration by activation of a hitherto unidentified neurokinin-3 receptor in the membrane of atrial myocytes. NK-3R stimulation may therefore represent an anti-arrhythmic concept to suppress re-entry-based atrial tachyarrhythmias, including AF. The cardiac autonomic nervous system produces various neuropeptides, such as neurokinin substance-P (Sub-P), whose function remains largely unclear. Here, authors show that Sub-P causes a receptor-mediated prolongation of the atrial action potential through a reduced background potassium current, and prevents atrial fibrillation.
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21
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O'Donohoe PB, Huskens N, Turner PJ, Pandit JJ, Buckler KJ. A1899, PK-THPP, ML365, and Doxapram inhibit endogenous TASK channels and excite calcium signaling in carotid body type-1 cells. Physiol Rep 2018; 6:e13876. [PMID: 30284397 PMCID: PMC6170881 DOI: 10.14814/phy2.13876] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 08/24/2018] [Indexed: 01/10/2023] Open
Abstract
Sensing of hypoxia and acidosis in arterial chemoreceptors is thought to be mediated through the inhibition of TASK and possibly other (e.g., BKCa ) potassium channels which leads to membrane depolarization, voltage-gated Ca-entry, and neurosecretion. Here, we investigate the effects of pharmacological inhibitors on TASK channel activity and [Ca2+ ]i -signaling in isolated neonatal rat type-1 cells. PK-THPP inhibited TASK channel activity in cell attached patches by up to 90% (at 400 nmol/L). A1899 inhibited TASK channel activity by 35% at 400 nmol/L. PK-THPP, A1899 and Ml 365 all evoked a rapid increase in type-1 cell [Ca2+ ]i . These [Ca2+ ]i responses were abolished in Ca2+ -free solution and greatly attenuated by Ni2+ (2 mM) suggesting that depolarization and voltage-gated Ca2+ -entry mediated the rise in [Ca2+ ]i. Doxapram (50 μmol/L), a respiratory stimulant, also inhibited type-1 cell TASK channel activity and increased [Ca2+ ]i. . We also tested the effects of combined inhibition of BKCa and TASK channels. TEA (5 mmol/L) slightly increased [Ca2+ ]i in the presence of PK-THPP and A1899. Paxilline (300 nM) and iberiotoxin (50 nmol/L) also slightly increased [Ca2+ ]i in the presence of A1899 but not in the presence of PK-THPP. In general [Ca2+ ]i responses to TASK inhibitors, alone or in combination with BKCa inhibitors, were smaller than the [Ca2+ ]i responses evoked by hypoxia. These data confirm that TASK channel inhibition is capable of evoking membrane depolarization and robust voltage-gated Ca2+ -entry but suggest that this, even with concomitant inhibition of BKCa channels, may be insufficient to account fully for the [Ca2+ ]i -response to hypoxia.
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Affiliation(s)
- Peadar B. O'Donohoe
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUnited Kingdom
- Nuffield Department of AnaestheticsOxford University HospitalsOxfordUnited Kingdom
| | - Nicky Huskens
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUnited Kingdom
| | - Philip J. Turner
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUnited Kingdom
| | - Jaideep J. Pandit
- Nuffield Department of AnaestheticsOxford University HospitalsOxfordUnited Kingdom
| | - Keith J. Buckler
- Department of Physiology, Anatomy and GeneticsUniversity of OxfordOxfordUnited Kingdom
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Calvo D, Filgueiras-Rama D, Jalife J. Mechanisms and Drug Development in Atrial Fibrillation. Pharmacol Rev 2018; 70:505-525. [PMID: 29921647 PMCID: PMC6010660 DOI: 10.1124/pr.117.014183] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Atrial fibrillation is a highly prevalent cardiac arrhythmia and the most important cause of embolic stroke. Although genetic studies have identified an increasing assembly of AF-related genes, the impact of these genetic discoveries is yet to be realized. In addition, despite more than a century of research and speculation, the molecular and cellular mechanisms underlying AF have not been established, and therapy for AF, particularly persistent AF, remains suboptimal. Current antiarrhythmic drugs are associated with a significant rate of adverse events, particularly proarrhythmia, which may explain why many highly symptomatic AF patients are not receiving any rhythm control therapy. This review focuses on recent advances in AF research, including its epidemiology, genetics, and pathophysiological mechanisms. We then discuss the status of antiarrhythmic drug therapy for AF today, reviewing molecular mechanisms, and the possible clinical use of some of the new atrial-selective antifibrillatory agents, as well as drugs that target atrial remodeling, inflammation and fibrosis, which are being tested as upstream therapies to prevent AF perpetuation. Altogether, the objective is to highlight the magnitude and endemic dimension of AF, which requires a significant effort to develop new and effective antiarrhythmic drugs, but also improve AF prevention and treatment of risk factors that are associated with AF complications.
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Affiliation(s)
- David Calvo
- Department of Cardiology, Arrhythmia Unit, Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain (D.C.); Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain (D.F.-R., J.J.); Department of Cardiology, Arrhythmia Unit, Hospital Clínico Universitario San Carlos, Madrid, Spain (D.F.-R.); Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain (D.F.-R., J.J.); and Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (J.J.)
| | - David Filgueiras-Rama
- Department of Cardiology, Arrhythmia Unit, Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain (D.C.); Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain (D.F.-R., J.J.); Department of Cardiology, Arrhythmia Unit, Hospital Clínico Universitario San Carlos, Madrid, Spain (D.F.-R.); Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain (D.F.-R., J.J.); and Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (J.J.)
| | - José Jalife
- Department of Cardiology, Arrhythmia Unit, Hospital Universitario Central de Asturias and Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain (D.C.); Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain (D.F.-R., J.J.); Department of Cardiology, Arrhythmia Unit, Hospital Clínico Universitario San Carlos, Madrid, Spain (D.F.-R.); Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain (D.F.-R., J.J.); and Center for Arrhythmia Research, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan (J.J.)
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Skarsfeldt MA, Bomholtz SH, Lundegaard PR, Lopez-Izquierdo A, Tristani-Firouzi M, Bentzen BH. Atrium-specific ion channels in the zebrafish-A role of I KACh in atrial repolarization. Acta Physiol (Oxf) 2018; 223:e13049. [PMID: 29412518 DOI: 10.1111/apha.13049] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 01/26/2018] [Accepted: 01/29/2018] [Indexed: 12/16/2022]
Abstract
AIM The zebrafish has emerged as a novel model for investigating cardiac physiology and pathology. The aim of this study was to investigate the atrium-specific ion channels responsible for shaping the atrial cardiac action potential in zebrafish. METHODS Using quantitative polymerase chain reaction, we assessed the expression level of atrium-specific potassium channels. The functional role of these channels was studied by patch clamp experiments on isolated atrial and ventricular cardiomyocytes and by optical mapping of explanted adult zebrafish hearts. Finally, surface ECGs were recorded to establish possible in vivo roles of atrial ion channels. RESULTS In isolated adult zebrafish hearts, we identified the expression of kcnk3, kcnk9, kcnn1, kcnn2, kcnn3, kcnj3 and kcnj5, the genes that encode the atrium-specific K2P , KCa 2.x and Kir 3.1/4 (KACh ) ion channels. The electrophysiological data indicate that the acetylcholine-activated inward-rectifying current, IKACh, plays a major role in the zebrafish atrium, whereas K2P 3.1/9.1 and KCa 2.x channels do not appear to be involved in regulating the action potential in the zebrafish heart. CONCLUSION We demonstrate that the acetylcholine-activated inward-rectifying current (IKACh ) current plays a major role in the zebrafish atrium and that the zebrafish could potentially be a cost-effective and reliable model for pharmacological testing of atrium-specific IKACh modulating compounds.
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Affiliation(s)
- M. A. Skarsfeldt
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
- Nora Eccles Harrison Cardiovascular Research and Training Institute; University of Utah; Salt Lake City UT USA
| | - S. H. Bomholtz
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
| | - P. R. Lundegaard
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
| | - A. Lopez-Izquierdo
- Nora Eccles Harrison Cardiovascular Research and Training Institute; University of Utah; Salt Lake City UT USA
| | - M. Tristani-Firouzi
- Nora Eccles Harrison Cardiovascular Research and Training Institute; University of Utah; Salt Lake City UT USA
| | - B. H. Bentzen
- Department of Biomedical Sciences; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
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24
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Wright PD, Veale EL, McCoull D, Tickle DC, Large JM, Ococks E, Gothard G, Kettleborough C, Mathie A, Jerman J. Terbinafine is a novel and selective activator of the two-pore domain potassium channel TASK3. Biochem Biophys Res Commun 2017; 493:444-450. [DOI: 10.1016/j.bbrc.2017.09.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 09/01/2017] [Indexed: 12/12/2022]
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25
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Crosstalk between KCNK3-Mediated Ion Current and Adrenergic Signaling Regulates Adipose Thermogenesis and Obesity. Cell 2017; 171:836-848.e13. [PMID: 28988768 DOI: 10.1016/j.cell.2017.09.015] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 06/10/2017] [Accepted: 09/08/2017] [Indexed: 01/13/2023]
Abstract
Adrenergic stimulation promotes lipid mobilization and oxidation in brown and beige adipocytes, where the harnessed energy is dissipated as heat in a process known as adaptive thermogenesis. The signaling cascades and energy-dissipating pathways that facilitate thermogenesis have been extensively described, yet little is known about the counterbalancing negative regulatory mechanisms. Here, we identify a two-pore-domain potassium channel, KCNK3, as a built-in rheostat negatively regulating thermogenesis. Kcnk3 is transcriptionally wired into the thermogenic program by PRDM16, a master regulator of thermogenesis. KCNK3 antagonizes norepinephrine-induced membrane depolarization by promoting potassium efflux in brown adipocytes. This limits calcium influx through voltage-dependent calcium channels and dampens adrenergic signaling, thereby attenuating lipolysis and thermogenic respiration. Adipose-specific Kcnk3 knockout mice display increased energy expenditure and are resistant to hypothermia and obesity. These findings uncover a critical K+-Ca2+-adrenergic signaling axis that acts to dampen thermogenesis, maintain tissue homeostasis, and reveal an electrophysiological regulatory mechanism of adipocyte function.
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26
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Vierra NC, Dadi PK, Milian SC, Dickerson MT, Jordan KL, Gilon P, Jacobson DA. TALK-1 channels control β cell endoplasmic reticulum Ca 2+ homeostasis. Sci Signal 2017; 10:eaan2883. [PMID: 28928238 PMCID: PMC5672804 DOI: 10.1126/scisignal.aan2883] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ca2+ handling by the endoplasmic reticulum (ER) serves critical roles in controlling pancreatic β cell function and becomes perturbed during the pathogenesis of diabetes. ER Ca2+ homeostasis is determined by ion movements across the ER membrane, including K+ flux through K+ channels. We demonstrated that K+ flux through ER-localized TALK-1 channels facilitated Ca2+ release from the ER in mouse and human β cells. We found that β cells from mice lacking TALK-1 exhibited reduced basal cytosolic Ca2+ and increased ER Ca2+ concentrations, suggesting reduced ER Ca2+ leak. These changes in Ca2+ homeostasis were presumably due to TALK-1-mediated ER K+ flux, because we recorded K+ currents mediated by functional TALK-1 channels on the nuclear membrane, which is continuous with the ER. Moreover, overexpression of K+-impermeable TALK-1 channels in HEK293 cells did not reduce ER Ca2+ stores. Reduced ER Ca2+ content in β cells is associated with ER stress and islet dysfunction in diabetes, and islets from TALK-1-deficient mice fed a high-fat diet showed reduced signs of ER stress, suggesting that TALK-1 activity exacerbated ER stress. Our data establish TALK-1 channels as key regulators of β cell ER Ca2+ and suggest that TALK-1 may be a therapeutic target to reduce ER Ca2+ handling defects in β cells during the pathogenesis of diabetes.
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Affiliation(s)
- Nicholas C Vierra
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Prasanna K Dadi
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Sarah C Milian
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Matthew T Dickerson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Kelli L Jordan
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA
| | - Patrick Gilon
- Pôle d'endocrinologie, diabète et nutrition, Institut de recherche expérimentale et clinique, Université catholique de Louvain, Brussels 1200, Belgium
| | - David A Jacobson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN 37232, USA.
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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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28
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Ravens U. Atrial-selective K + channel blockers: potential antiarrhythmic drugs in atrial fibrillation? Can J Physiol Pharmacol 2017; 95:1313-1318. [PMID: 28738160 DOI: 10.1139/cjpp-2017-0024] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In the wake of demographic change in Western countries, atrial fibrillation has reached an epidemiological scale, yet current strategies for drug treatment of the arrhythmia lack sufficient efficacy and safety. In search of novel medications, atrial-selective drugs that specifically target atrial over other cardiac functions have been developed. Here, I will address drugs acting on potassium (K+) channels that are either predominantly expressed in atria or possess electrophysiological properties distinct in atria from ventricles. These channels include the ultra-rapidly activating, delayed outward-rectifying Kv1.5 channel conducting IKur, the acetylcholine-activated inward-rectifying Kir3.1/Kir3.4 channel conducting IK,ACh, the Ca2+-activated K+ channels of small conductance (SK) conducting ISK, and the two-pore domain K+ (K2P) channels (tandem of P domains, weak inward-rectifying K+ channels (TWIK-1), TWIK-related acid-sensitive K+ channels (TASK-1 and TASK-3)) that are responsible for voltage-independent background currents ITWIK-1, ITASK-1, and ITASK-3. Direct drug effects on these channels are described and their putative value in treatment of atrial fibrillation is discussed. Although many potential drug targets have emerged in the process of unravelling details of the pathophysiological mechanisms responsible for atrial fibrillation, we do not know whether novel antiarrhythmic drugs will be more successful when modulating many targets or a single specific one. The answer to this riddle can only be solved in a clinical context.
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Affiliation(s)
- Ursula Ravens
- Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg - Bad Krozingen, University of Freiburg, Germany; Institute of Physiology, Medical Faculty Carl Gustav Carus, TU Dresden, Germany.,Institute of Experimental Cardiovascular Medicine, University Heart Center Freiburg - Bad Krozingen, University of Freiburg, Germany; Institute of Physiology, Medical Faculty Carl Gustav Carus, TU Dresden, Germany
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29
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Ramírez D, Arévalo B, Martínez G, Rinné S, Sepúlveda FV, Decher N, González W. Side Fenestrations Provide an "Anchor" for a Stable Binding of A1899 to the Pore of TASK-1 Potassium Channels. Mol Pharm 2017; 14:2197-2208. [PMID: 28494157 DOI: 10.1021/acs.molpharmaceut.7b00005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A1899 is a potent and selective inhibitor of the two-pore domain potassium (K2P) channel TASK-1. It was previously reported that A1899 acts as an open-channel blocker and binds to residues of the P1 and P2 regions, the M2 and M4 segments, and the halothane response element. The recently described crystal structures of K2P channels together with the newly identified side fenestrations indicate that residues relevant for TASK-1 inhibition are not purely facing the central cavity as initially proposed. Accordingly, the TASK-1 binding site and the mechanism of inhibition might need a re-evaluation. We have used TASK-1 homology models based on recently crystallized K2P channels and molecular dynamics simulation to demonstrate that the highly potent TASK-1 blocker A1899 requires binding to residues located in the side fenestrations. Unexpectedly, most of the previously described residues that interfere with TASK-1 blockade by A1899 project their side chains toward the fenestration lumina, underlining the relevance of these structures for drug binding in K2P channels. Despite its hydrophobicity, A1899 does not seem to use the fenestrations to gain access to the central cavity from the lipid bilayer. In contrast, binding of A1899 to residues of the side fenestrations might provide a physical "anchor", reflecting an energetically favorable binding mode that after pore occlusion stabilizes the closed state of the channels.
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Affiliation(s)
- David Ramírez
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca , 1 poniente No. 1141, 3460000 Talca, Chile.,Instituto de Ciencias Biomédicas, Universidad Autonoma de Chile , 5 Poniente No. 1670, 3460000 Talca, Chile
| | - Bárbara Arévalo
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca , 1 poniente No. 1141, 3460000 Talca, Chile
| | - Gonzalo Martínez
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca , 1 poniente No. 1141, 3460000 Talca, Chile
| | - Susanne Rinné
- Institute for Physiology and Pathophysiology, Vegetative Physiology Group, University of Marburg , 35037 Marburg, Germany
| | | | - Niels Decher
- Institute for Physiology and Pathophysiology, Vegetative Physiology Group, University of Marburg , 35037 Marburg, Germany
| | - Wendy González
- Centro de Bioinformática y Simulación Molecular, Universidad de Talca , 1 poniente No. 1141, 3460000 Talca, Chile
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30
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Inhibition of potassium currents is involved in antiarrhythmic effect of moderate ethanol on atrial fibrillation. Toxicol Appl Pharmacol 2017; 322:89-96. [DOI: 10.1016/j.taap.2017.03.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/01/2017] [Accepted: 03/07/2017] [Indexed: 12/27/2022]
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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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32
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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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33
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High throughput screening technologies for ion channels. Acta Pharmacol Sin 2016; 37:34-43. [PMID: 26657056 DOI: 10.1038/aps.2015.108] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 10/12/2015] [Indexed: 11/08/2022] Open
Abstract
Ion channels are involved in a variety of fundamental physiological processes, and their malfunction causes numerous human diseases. Therefore, ion channels represent a class of attractive drug targets and a class of important off-targets for in vitro pharmacological profiling. In the past decades, the rapid progress in developing functional assays and instrumentation has enabled high throughput screening (HTS) campaigns on an expanding list of channel types. Chronologically, HTS methods for ion channels include the ligand binding assay, flux-based assay, fluorescence-based assay, and automated electrophysiological assay. In this review we summarize the current HTS technologies for different ion channel classes and their applications.
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35
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Crestey F, Frederiksen K, Jensen HS, Dekermendjian K, Larsen PH, Bastlund JF, Lu D, Liu H, Yang CR, Grunnet M, Svenstrup N. Identification and electrophysiological evaluation of 2-methylbenzamide derivatives as Nav1.1 modulators. ACS Chem Neurosci 2015; 6:1302-8. [PMID: 26114759 DOI: 10.1021/acschemneuro.5b00147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Voltage-gated sodium channels (Nav) are crucial to the initiation and propagation of action potentials (APs) in electrically excitable cells, and during the past decades they have received considerable attention due to their therapeutic potential. Here, we report for the first time the synthesis and the electrophysiological evaluation of 16 ligands based on a 2-methylbenzamide scaffold that have been identified as Nav1.1 modulators. Among these compounds, N,N'-(1,3-phenylene)bis(2-methylbenzamide) (3a) has been selected and evaluated in ex-vivo experiments in order to estimate the activation impact of such a compound profile. It appears that 3a increases the Nav1.1 channel activity although its overall impact remains moderate. Altogether, our preliminary results provide new insights into the development of small molecule activators targeting specifically Nav1.1 channels to design potential drugs for treating CNS diseases.
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Affiliation(s)
- François Crestey
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Kristen Frederiksen
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Henrik S. Jensen
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Kim Dekermendjian
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Peter H. Larsen
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Jesper F. Bastlund
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Dunguo Lu
- ChemPartner Co.
Ltd., 998 Halei Road, Zhangjiang Hi-Tech
Park, Shanghai 201203, P. R. China
| | - Henry Liu
- ChemPartner Co.
Ltd., 998 Halei Road, Zhangjiang Hi-Tech
Park, Shanghai 201203, P. R. China
| | - Charles R. Yang
- ChemPartner Co.
Ltd., 998 Halei Road, Zhangjiang Hi-Tech
Park, Shanghai 201203, P. R. China
| | - Morten Grunnet
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
| | - Niels Svenstrup
- Neuroscience Drug
Discovery, H. Lundbeck A/S, Ottiliavej
9, 2500 Valby, Denmark
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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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TASK channels in arterial chemoreceptors and their role in oxygen and acid sensing. Pflugers Arch 2015; 467:1013-25. [PMID: 25623783 PMCID: PMC4428840 DOI: 10.1007/s00424-015-1689-1] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 01/06/2015] [Accepted: 01/07/2015] [Indexed: 01/05/2023]
Abstract
Arterial chemoreceptors play a vital role in cardiorespiratory control by providing the brain with information regarding blood oxygen, carbon dioxide, and pH. The main chemoreceptor, the carotid body, is composed of sensory (type 1) cells which respond to hypoxia or acidosis with a depolarising receptor potential which in turn activates voltage-gated calcium entry, neurosecretion and excitation of adjacent afferent nerves. The receptor potential is generated by inhibition of Twik-related acid-sensitive K(+) channel 1 and 3 (TASK1/TASK3) heterodimeric channels which normally maintain the cells' resting membrane potential. These channels are thought to be directly inhibited by acidosis. Oxygen sensitivity, however, probably derives from a metabolic signalling pathway. The carotid body, isolated type 1 cells, and all forms of TASK channel found in the type 1 cell, are highly sensitive to inhibitors of mitochondrial metabolism. Moreover, type1 cell TASK channels are activated by millimolar levels of MgATP. In addition to their role in the transduction of chemostimuli, type 1 cell TASK channels have also been implicated in the modulation of chemoreceptor function by a number of neurocrine/paracrine signalling molecules including adenosine, GABA, and serotonin. They may also be instrumental in mediating the depression of the acute hypoxic ventilatory response that occurs with some general anaesthetics. Modulation of TASK channel activity is therefore a key mechanism by which the excitability of chemoreceptors can be controlled. This is not only of physiological importance but may also offer a therapeutic strategy for the treatment of cardiorespiratory disorders that are associated with chemoreceptor dysfunction.
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Ehling P, Cerina M, Budde T, Meuth SG, Bittner S. The CNS under pathophysiologic attack--examining the role of K₂p channels. Pflugers Arch 2014; 467:959-72. [PMID: 25482672 DOI: 10.1007/s00424-014-1664-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 11/17/2014] [Accepted: 11/28/2014] [Indexed: 10/24/2022]
Abstract
Members of the two-pore domain K(+) channel (K2P) family are increasingly recognized as being potential targets for therapeutic drugs and could play a role in the diagnosis and treatment of neurologic disorders. Their broad and diverse expression pattern in pleiotropic cell types, importance in cellular function, unique biophysical properties, and sensitivity toward pathophysiologic parameters represent the basis for their involvement in disorders of the central nervous system (CNS). This review will focus on multiple sclerosis (MS) and stroke, as there is growing evidence for the involvement of K2P channels in these two major CNS disorders. In MS, TASK1-3 channels are expressed on T lymphocytes and are part of a signaling network regulating Ca(2+)- dependent pathways that are mandatory for T cell activation, differentiation, and effector functions. In addition, TASK1 channels are involved in neurodegeneration, resulting in autoimmune attack of CNS cells. On the blood-brain barrier, TREK1 channels regulate immune cell trafficking under autoinflammatory conditions. Cerebral ischemia shares some pathophysiologic similarities with MS, including hypoxia and extracellular acidosis. On a cellular level, K2P channels can have both proapoptotic and antiapoptotic effects, either promoting neurodegeneration or protecting neurons from ischemic cell death. TASK1 and TREK1 channels have a neuroprotective effect on stroke development, whereas TASK2 channels have a detrimental effect on neuronal survival under ischemic conditions. Future research in preclinical models is needed to provide a more detailed understanding of the contribution of K2P channel family members to neurologic disorders, before translation to the clinic is an option.
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Affiliation(s)
- Petra Ehling
- Department of Neurology, University of Münster, Münster, Germany,
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