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Peixoto-Neves D, Jaggar JH. Physiological functions and pathological involvement of ion channel trafficking in the vasculature. J Physiol 2024; 602:3275-3296. [PMID: 37818949 PMCID: PMC11006830 DOI: 10.1113/jp285007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 09/28/2023] [Indexed: 10/13/2023] Open
Abstract
A variety of ion channels regulate membrane potential and calcium influx in arterial smooth muscle and endothelial cells to modify vascular functions, including contractility. The current (I) generated by a population of ion channels is equally dependent upon their number (N), open probability (Po) and single channel current (i), such that I = N.PO.i. A conventional view had been that ion channels traffic to the plasma membrane in a passive manner, resulting in a static surface population. It was also considered that channels assemble with auxiliary subunits prior to anterograde trafficking of the multimeric complex to the plasma membrane. Recent studies have demonstrated that physiological stimuli can regulate the surface abundance (N) of several different ion channels in arterial smooth muscle and endothelial cells to control arterial contractility. Physiological stimuli can also regulate the number of auxiliary subunits present in the plasma membrane to modify the biophysical properties, regulatory mechanisms and physiological functions of some ion channels. Furthermore, ion channel trafficking becomes dysfunctional in the vasculature during hypertension, which negatively impacts the regulation of contractility. The temporal kinetics of ion channel and auxiliary subunit trafficking can also vary depending on the signalling mechanisms and proteins involved. This review will summarize recent work that has uncovered the mechanisms, functions and pathological modifications of ion channel trafficking in arterial smooth muscle and endothelial cells.
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Affiliation(s)
| | - Jonathan H. Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis TN 38139
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Saxena H, Weintraub NL, Tang Y. Potential Therapeutic Targets for Hypotension in Duchenne Muscular Dystrophy. Med Hypotheses 2024; 185:111318. [PMID: 38585412 PMCID: PMC10993928 DOI: 10.1016/j.mehy.2024.111318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
Duchenne Muscular Dystrophy (DMD) is marked by genetic mutations occurring in the DMD gene, which is widely expressed in the cardiovascular system. In addition to developing cardiomyopathy, patients with DMD have been reported to be susceptible to the development of symptomatic hypotension, although the mechanisms are unclear. Analysis of single-cell RNA sequencing data has identified potassium voltage-gated channel subfamily Q member 5 (KCNQ5) and possibly ryanodine receptor 2 (RyR2) as potential candidate hypotension genes whose expression is significantly upregulated in the vascular smooth muscle cells of DMD mutant mice. We hypothesize that heightened KCNQ5 and RyR2 expression contributes to decreased arterial blood pressure in patients with DMD. Exploring pharmacological approaches to inhibit the KCNQ5 and RyR2 channels holds promise in managing the systemic hypotension observed in individuals with DMD. This avenue of investigation presents new prospects for improving clinical outcomes for these patients.
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Affiliation(s)
- Harshi Saxena
- Vascular Biology Center, Department of Medicine, Medical College of Georgia at Augusta University, 1460 Laney Walker Blvd, Augusta, GA 30912, USA
| | - Neal L Weintraub
- Vascular Biology Center, Department of Medicine, Medical College of Georgia at Augusta University, 1460 Laney Walker Blvd, Augusta, GA 30912, USA
| | - Yaoliang Tang
- Vascular Biology Center, Department of Medicine, Medical College of Georgia at Augusta University, 1460 Laney Walker Blvd, Augusta, GA 30912, USA
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3
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Celentano C, Carotenuto L, Miceli F, Carleo G, Corrado B, Baroli G, Iervolino S, Vecchione R, Taglialatela M, Barrese V. Kv7 channel activation reduces brain endothelial cell permeability and prevents kainic acid-induced blood-brain barrier damage. Am J Physiol Cell Physiol 2024; 326:C893-C904. [PMID: 38284124 PMCID: PMC11193483 DOI: 10.1152/ajpcell.00709.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/22/2024] [Accepted: 01/22/2024] [Indexed: 01/30/2024]
Abstract
Ion channels in the blood-brain barrier (BBB) play a main role in controlling the interstitial fluid composition and cerebral blood flow, and their dysfunction contributes to the disruption of the BBB occurring in many neurological diseases such as epilepsy. In this study, using morphological and functional approaches, we evaluated the expression and role in the BBB of Kv7 channels, a family of voltage-gated potassium channels including five members (Kv7.1-5) that play a major role in the regulation of cell excitability and transmembrane flux of potassium ions. Immunofluorescence experiments showed that Kv7.1, Kv7.4, and Kv7.5 were expressed in rat brain microvessels (BMVs), as well as brain primary- and clonal (BEND-3) endothelial cells (ECs). Kv7.5 localized at the cell-to-cell junction sites, whereas Kv7.4 was also found in pericytes. The Kv7 activator retigabine increased transendothelial electrical resistance (TEER) in both primary ECs and BEND-3 cells; moreover, retigabine reduced paracellular dextran flux in BEND-3 cells. These effects were prevented by the selective Kv7 blocker XE-991. Exposure to retigabine also hyperpolarized cell membrane and increased tight junctions (TJs) integrity in BEND-3 cells. BMVs from rats treated with kainic acid (KA) showed a disruption of TJs and a selective reduction of Kv7.5 expression. In BEND-3 cells, retigabine prevented the increase of cell permeability and the reduction of TJs integrity induced by KA. Overall, these findings demonstrate that Kv7 channels are expressed in the BBB, where they modulate barrier properties both in physiological and pathological conditions.NEW & NOTEWORTHY This study describes for the first time the expression and the functional role of Kv7 potassium channels in the blood-brain barrier. We show that the opening of Kv7 channels reduces endothelial cell permeability both in physiological and pathological conditions via the hyperpolarization of cell membrane and the sealing of tight junctions. Therefore, activation of endothelial Kv7 channels might be a useful strategy to treat epilepsy and other neurological disorders characterized by blood-brain barrier dysfunction.
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Affiliation(s)
- Camilla Celentano
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Lidia Carotenuto
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Francesco Miceli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Giusy Carleo
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Brunella Corrado
- Interdisciplinary Research Centre on Biomaterials, University of Naples Federico II, Naples, Italy
- Center for Advanced Biomaterials for Health Care, Istituto Italiano di Tecnologia, Naples, Italy
| | - Giulia Baroli
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Stefania Iervolino
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Raffaele Vecchione
- Center for Advanced Biomaterials for Health Care, Istituto Italiano di Tecnologia, Naples, Italy
| | - Maurizio Taglialatela
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
| | - Vincenzo Barrese
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy
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4
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Tsvetkov D, Schleifenbaum J, Wang Y, Kassmann M, Polovitskaya MM, Ali M, Schütze S, Rothe M, Luft FC, Jentsch TJ, Gollasch M. KCNQ5 Controls Perivascular Adipose Tissue-Mediated Vasodilation. Hypertension 2024; 81:561-571. [PMID: 38354270 DOI: 10.1161/hypertensionaha.123.21834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Accepted: 12/12/2023] [Indexed: 02/16/2024]
Abstract
BACKGROUND Small arteries exhibit resting tone, a partially contracted state that maintains arterial blood pressure. In arterial smooth muscle cells, potassium channels control contraction and relaxation. Perivascular adipose tissue (PVAT) has been shown to exert anticontractile effects on the blood vessels. However, the mechanisms by which PVAT signals small arteries, and their relevance remain largely unknown. We aimed to uncover key molecular components in adipose-vascular coupling. METHODS A wide spectrum of genetic mouse models targeting Kcnq3, Kcnq4, and Kcnq5 genes (Kcnq3-/-, Kcnq4-/-, Kcnq5-/-, Kcnq5dn/dn, Kcnq4-/-/Kcnq5dn/dn, and Kcnq4-/-/Kcnq5-/-), telemetry blood pressure measurements, targeted lipidomics, RNA-Seq profiling, wire-myography, patch-clamp, and sharp-electrode membrane potential measurements was used. RESULTS We show that PVAT causes smooth muscle cell KV7.5 family of voltage-gated potassium (K+) channels to hyperpolarize the membrane potential. This effect relaxes small arteries and regulates blood pressure. Oxygenation of polyunsaturated fats generates oxylipins, a superclass of lipid mediators. We identified numerous oxylipins released by PVAT, which potentiate vasodilatory action in small arteries by opening smooth muscle cell KV7.5 family of voltage-gated potassium (K+) channels. CONCLUSIONS Our results reveal a key molecular function of the KV7.5 family of voltage-gated potassium (K+) channels in the adipose-vascular coupling, translating PVAT signals, particularly oxylipins, to the central physiological function of vasoregulation. This novel pathway opens new therapeutic perspectives.
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Affiliation(s)
- Dmitry Tsvetkov
- Department of Internal Medicine and Geriatrics, University Medicine Greifswald, Germany (D.T., M.K., M.A., M.G.)
| | - Johanna Schleifenbaum
- Institute of Vegetative Physiology, Charité-Universitätsmedizin Berlin, Germany (J.S.)
| | - Yibin Wang
- Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine, Berlin, Germany (Y.W., F.C.L.)
| | - Mario Kassmann
- Department of Internal Medicine and Geriatrics, University Medicine Greifswald, Germany (D.T., M.K., M.A., M.G.)
| | - Maya M Polovitskaya
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany (M.M.P., S.S., T.J.J.)
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany (M.M.P., S.S., T.J.J.)
| | - Mohamed Ali
- Department of Internal Medicine and Geriatrics, University Medicine Greifswald, Germany (D.T., M.K., M.A., M.G.)
| | - Sebastian Schütze
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany (M.M.P., S.S., T.J.J.)
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany (M.M.P., S.S., T.J.J.)
| | | | - Friedrich C Luft
- Experimental and Clinical Research Center, a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine, Berlin, Germany (Y.W., F.C.L.)
| | - Thomas J Jentsch
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany (M.M.P., S.S., T.J.J.)
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany (M.M.P., S.S., T.J.J.)
- NeuroCure Cluster of Excellence, Charité-Universitätsmedizin Berlin, Berlin, Germany (T.J.J.)
| | - Maik Gollasch
- Department of Internal Medicine and Geriatrics, University Medicine Greifswald, Germany (D.T., M.K., M.A., M.G.)
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Zhuang W, Mun SY, Park M, Jeong J, Kim HR, Na S, Lee SJ, Park H, Park WS. Inhibition of voltage-dependent K + channels in rabbit coronary arterial smooth muscle cells by the atypical antipsychotic agent sertindole. J Appl Toxicol 2024; 44:391-399. [PMID: 37786982 DOI: 10.1002/jat.4549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/13/2023] [Accepted: 09/18/2023] [Indexed: 10/04/2023]
Abstract
The regulation of membrane potential and the contractility of vascular smooth muscle cells (VSMCs) by voltage-dependent K+ (Kv) potassium channels are well-established. In this study, native VSMCs from rabbit coronary arteries were used to investigate the inhibitory effect of sertindole, an atypical antipsychotic agent, on Kv channels. Sertindole induced dose-dependent inhibition of Kv channels, with an IC50 of 3.13 ± 0.72 μM. Although sertindole did not cause a change in the steady-state activation curve, it did lead to a negative shift in the steady-state inactivation curve. The application of 1- or 2-Hz train pulses failed to alter the sertindole-induced inhibition of Kv channels, suggesting use-independent effects of the drug. The inhibitory response to sertindole was significantly diminished by pretreatment with a Kv1.5 inhibitor but not by Kv2.1 and Kv7 subtype inhibitors. These findings demonstrate the sertindole dose-dependent and use-independent inhibition of vascular Kv channels (mainly the Kv1.5 subtype) through a mechanism that involves altering steady-state inactivation curves. Therefore, the use of sertindole as an antipsychotic drug may have adverse effects on the cardiovascular system.
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Affiliation(s)
- Wenwen Zhuang
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Seo-Yeong Mun
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Minju Park
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Junsu Jeong
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Hye Ryung Kim
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Sunghun Na
- Institute of Medical Sciences, Department of Obstetrics and Gynecology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Se Jin Lee
- Institute of Medical Sciences, Department of Obstetrics and Gynecology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Hongzoo Park
- Institute of Medical Sciences, Department of Urology, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Won Sun Park
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, South Korea
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Baldwin SN, Jepps TA, Greenwood IA. Cycling matters: Sex hormone regulation of vascular potassium channels. Channels (Austin) 2023; 17:2217637. [PMID: 37243715 PMCID: PMC10228406 DOI: 10.1080/19336950.2023.2217637] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/07/2023] [Accepted: 05/19/2023] [Indexed: 05/29/2023] Open
Abstract
Sex hormones and the reproductive cycle (estrus in rodents and menstrual in humans) have a known impact on arterial function. In spite of this, sex hormones and the estrus/menstrual cycle are often neglected experimental factors in vascular basic preclinical scientific research. Recent research by our own laboratory indicates that cyclical changes in serum concentrations of sex -hormones across the rat estrus cycle, primary estradiol, have significant consequences for the subcellular trafficking and function of KV. Vascular potassium channels, including KV, are essential components of vascular reactivity. Our study represents a small part of a growing field of literature aimed at determining the role of sex hormones in regulating arterial ion channel function. This review covers key findings describing the current understanding of sex hormone regulation of vascular potassium channels, with a focus on KV channels. Further, we highlight areas of research where the estrus cycle should be considered in future studies to determine the consequences of physiological oscillations in concentrations of sex hormones on vascular potassium channel function.
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Affiliation(s)
- Samuel N Baldwin
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Iain A Greenwood
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George’s University of London, London, UK
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7
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Shen Y, Kim IM, Tang Y. Identification of Novel Gene Regulatory Networks for Dystrophin Protein in Vascular Smooth Muscle Cells by Single-Nuclear Transcriptome Analysis. Cells 2023; 12:892. [PMID: 36980233 PMCID: PMC10047041 DOI: 10.3390/cells12060892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 03/01/2023] [Accepted: 03/04/2023] [Indexed: 03/15/2023] Open
Abstract
Duchenne muscular dystrophy is an X-linked recessive disease caused by mutations in dystrophin proteins that lead to heart failure and respiratory failure. Dystrophin (DMD) is not only expressed in cardiomyocytes and skeletal muscle cells, but also in vascular smooth muscle cells (VSMCs). Patients with DMD have been reported to have hypotension. Single nuclear RNA sequencing (snRNA-seq) is a state-of-the-art technology capable of identifying niche-specific gene programs of tissue-specific cell subpopulations. To determine whether DMD mutation alters blood pressure, we compared systolic, diastolic, and mean blood pressure levels in mdx mice (a mouse model of DMD carrying a nonsense mutation in DMD gene) and the wide-type control mice. We found that mdx mice showed significantly lower systolic, diastolic, and mean blood pressure than control mice. To understand how DMD mutation changes gene expression profiles from VSMCs, we analyzed an snRNA-seq dataset from the muscle nucleus of DMD mutant (DMDmut) mice and control (Ctrl) mice. Gene Ontology (GO) enrichment analysis revealed that the most significantly activated pathways in DMDmut-VSMCs are involved in ion channel function (potassium channel activity, cation channel complex, and cation channel activity). Notably, we discovered that the DMDmut-VSMCs showed significantly upregulated expression of KCNQ5 and RYR2, whereas the most suppressed pathways were transmembrane transporter activity (such as anion transmembrane transporter activity, inorganic anion transmembrane transporter activity, import into cell, and import across plasma membrane). Moreover, we analyzed metabolic pathways from the Kyoto Encyclopedia of Genes and Genomes (KEGG) using "scMetabolism" R package. DMDmut-VSMCs exhibited dysregulation of pyruvate metabolism and nuclear acid metabolism. In conclusion, via the application of snRNA-seq, we (for the first time) identify the potential molecular regulation by DMD in the upregulation of the expression of KCNQ5 genes in VSMCs, which helps us to understand the mechanism of hypotension in DMD patients. Our study potentially offers new possibilities for therapeutic interventions in systemic hypotension in DMD patients with pharmacological inhibition of KCNQ5.
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Affiliation(s)
- Yan Shen
- Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Il-man Kim
- Department of Anatomy, Cell Biology and Physiology, School of Medicine, Indiana University, Indianapolis, IN 46202, USA
| | - Yaoliang Tang
- Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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Baldwin SN, Forrester EA, Homer NZM, Andrew R, Barrese V, Stott JB, Isakson BE, Albert AP, Greenwood IA. Marked oestrous cycle-dependent regulation of rat arterial K V 7.4 channels driven by GPER1. Br J Pharmacol 2023; 180:174-193. [PMID: 36085551 PMCID: PMC10091994 DOI: 10.1111/bph.15947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 06/21/2022] [Accepted: 07/20/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Kcnq-encoded KV 7 channels (termed KV 7.1-5) regulate vascular smooth muscle cell (VSMC) contractility at rest and as targets of receptor-mediated responses. However, the current data are mostly derived from males. Considering the known effects of sex, the oestrous cycle and sex hormones on vascular reactivity, here we have characterised the molecular and functional properties of KV 7 channels from renal and mesenteric arteries from female Wistar rats separated into di-oestrus and met-oestrus (F-D/M) and pro-oestrus and oestrus (F-P/E). EXPERIMENTAL APPROACH RT-qPCR, immunocytochemistry, proximity ligation assay and wire myography were performed in renal and mesenteric arteries. Circulating sex hormone concentrations were determined by liquid chromatography-tandem mass spectrometry. Whole-cell electrophysiology was undertaken on cells expressing KV 7.4 channels in association with G-protein-coupled oestrogen receptor 1 (GPER1). KEY RESULTS The KV 7.2-5 activators S-1 and ML213 and the pan-KV 7 inhibitor linopirdine were more effective in arteries from F-D/M compared with F-P/E animals. In VSMCs isolated from F-P/E rats, exploratory evidence indicates reduced membrane abundance of KV 7.4 but not KV 7.1, KV 7.5 and Kcne4 when compared with cells from F-D/M. Plasma oestradiol was higher in F-P/E compared with F-D/M, and progesterone showed the converse pattern. Oestradiol/GPER1 agonist G-1 diminished KV 7.4 encoded currents and ML213 relaxations and reduced the membrane abundance of KV 7.4 and interaction between KV 7.4 and heat shock protein 90 (HSP90), in arteries from F-D/M but not F-P/E. CONCLUSIONS AND IMPLICATIONS GPER1 signalling decreased KV 7.4 membrane abundance in conjunction with diminished interaction with HSP90, giving rise to a 'pro-contractile state'.
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Affiliation(s)
- Samuel N. Baldwin
- Vascular Biology Research Centre, Institute of Molecular and Clinical SciencesSt George's University of LondonLondonUK
| | - Elizabeth A. Forrester
- Vascular Biology Research Centre, Institute of Molecular and Clinical SciencesSt George's University of LondonLondonUK
| | - Natalie Z. M. Homer
- Mass Spectrometry Core Laboratory, Edinburgh Clinical Research Facility, Queen's Medical Research InstituteUniversity of EdinburghEdinburghUK
| | - Ruth Andrew
- Mass Spectrometry Core Laboratory, Edinburgh Clinical Research Facility, Queen's Medical Research InstituteUniversity of EdinburghEdinburghUK
- BHF Centre for Cardiovascular Science, Queen's Medical Research InstituteUniversity of EdinburghEdinburghUK
| | - Vincenzo Barrese
- Department of Neuroscience, Reproductive Sciences and DentistryUniversity of Naples Federico IINaplesItaly
| | - Jennifer B. Stott
- Vascular Biology Research Centre, Institute of Molecular and Clinical SciencesSt George's University of LondonLondonUK
| | - Brant E. Isakson
- Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research CentreUniversity of Virginia School of MedicineCharlottesvilleVirginiaUSA
| | - Anthony P. Albert
- Vascular Biology Research Centre, Institute of Molecular and Clinical SciencesSt George's University of LondonLondonUK
| | - Iain A. Greenwood
- Vascular Biology Research Centre, Institute of Molecular and Clinical SciencesSt George's University of LondonLondonUK
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Manville RW, Redford KE, van der Horst J, Hogenkamp DJ, Jepps TA, Abbott GW. KCNQ5 activation by tannins mediates vasorelaxant effects of barks used in Native American botanical medicine. FASEB J 2022; 36:e22457. [PMID: 35997997 PMCID: PMC9404676 DOI: 10.1096/fj.202200724r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/30/2022] [Accepted: 07/06/2022] [Indexed: 11/11/2022]
Abstract
Tree and shrub barks have been used as folk medicine by numerous cultures across the globe for millennia, for a variety of indications, including as vasorelaxants and antispasmodics. Here, using electrophysiology and myography, we discovered that the KCNQ5 voltage-gated potassium channel mediates vascular smooth muscle relaxant effects of barks used in Native American folk medicine. Bark extracts (1%) from Birch, Cramp Bark, Slippery Elm, White Oak, Red Willow, White Willow, and Wild Cherry each strongly activated KCNQ5 expressed in Xenopus oocytes. Testing of a subset including both the most and the least efficacious extracts revealed that Red Willow, White Willow, and White Oak KCNQ-dependently relaxed rat mesenteric arteries; in contrast, Black Haw bark neither activated KCNQ5 nor induced vasorelaxation. Two compounds common to the active barks (gallic acid and tannic acid) had similarly potent and efficacious effects on both KCNQ5 activation and vascular relaxation, and this together with KCNQ5 modulation by other tannins provides a molecular basis for smooth muscle relaxation effects of Native American folk medicine bark extracts.
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Affiliation(s)
- Rian W. Manville
- Bioelectricity Laboratory, Dept. of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Kaitlyn E. Redford
- Bioelectricity Laboratory, Dept. of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Jennifer van der Horst
- Department of Biomedical Sciences, Vascular Biology Group, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Derk J. Hogenkamp
- Bioelectricity Laboratory, Dept. of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Thomas A. Jepps
- Department of Biomedical Sciences, Vascular Biology Group, Panum Institute, University of Copenhagen, Copenhagen, Denmark
| | - Geoffrey W. Abbott
- Bioelectricity Laboratory, Dept. of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
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10
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Peixoto-Neves D, Kanthakumar P, Afolabi JM, Soni H, Buddington RK, Adebiyi A. K V7.1 channel blockade inhibits neonatal renal autoregulation triggered by a step decrease in arterial pressure. Am J Physiol Renal Physiol 2022; 322:F197-F207. [PMID: 35001664 PMCID: PMC8816635 DOI: 10.1152/ajprenal.00568.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
KV7 channels, the voltage-gated K+ channels encoded by KCNQ genes, mediate heterogeneous vascular responses in rodents. Postnatal changes in the functional expression of KV7 channels have been reported in rodent saphenous arteries, but their physiological function in the neonatal renal vascular bed is unclear. Here, we report that, unlike adult pigs, only KCNQ1 (KV7.1) out of the five members of KCNQ genes was detected in neonatal pig renal microvessels. KCNQ1 is present in fetal pig kidneys as early as day 50 of gestation, and the level of expression remains the same up to postnatal day 21. Activation of renal vascular smooth muscle cell (SMC) KV7.1 stimulated whole cell currents, inhibited by HMR1556 (HMR), a selective KV7.1 blocker. HMR did not change the steady-state diameter of isolated renal microvessels. Similarly, intrarenal artery infusion of HMR did not alter mean arterial pressure, renal blood flow, and renal vascular resistance in the pigs. An ∼20 mmHg reduction in mean arterial pressure evoked effective autoregulation of renal blood flow, which HMR inhibited. We conclude that 1) the expression of KCNQ isoforms in porcine renal microvessels is dependent on kidney maturation, 2) KV7.1 is functionally expressed in neonatal pig renal vascular SMCs, 3) a decrease in arterial pressure up to 20 mmHg induces renal autoregulation in neonatal pigs, and 4) SMC KV7.1 does not control basal renal vascular tone but contributes to neonatal renal autoregulation triggered by a step decrease in arterial pressure.NEW & NOTEWORTHY KV7.1 is present in fetal pig kidneys as early as day 50 of gestation, and the level of expression remains the same up to postnatal day 21. KV7.1 is functionally expressed in neonatal pig renal vascular smooth muscle cells (SMCs). A decrease in arterial pressure up to 20 mmHg induces renal autoregulation in neonatal pigs. Although SMC KV7.1 does not control basal renal vascular resistance, its inhibition blunts neonatal renal autoregulation engendered by a step decrease in arterial pressure.
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Affiliation(s)
- Dieniffer Peixoto-Neves
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Jeremiah M. Afolabi
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Hitesh Soni
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Adebowale Adebiyi
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
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Abstract
Since prehistory, human species have depended on plants for both food and medicine. Even in countries with ready access to modern medicines, alternative treatments are still highly regarded and commonly used. Unlike modern pharmaceuticals, many botanical medicines are in widespread use despite a lack of safety and efficacy data derived from controlled clinical trials and often unclear mechanisms of action. Contributing to this are the complex and undefined composition and likely multifactorial mechanisms of action and multiple targets of many botanical medicines. Here, we review the newfound importance of the ubiquitous KCNQ subfamily of voltage-gated potassium channels as targets for botanical medicines, including basil, capers, cilantro, lavender, fennel, chamomile, ginger, and Camellia, Sophora, and Mallotus species. We discuss the implications for the traditional use of these plants for disorders such as seizures, hypertension, and diabetes and the molecular mechanisms of plant secondary metabolite effects on KCNQ channels.
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Affiliation(s)
- Kaitlyn E Redford
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California 92697, USA;
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, California 92697, USA;
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12
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Baldwin SN, Forrester EA, McEwan L, Greenwood IA. Sexual dimorphism in prostacyclin-mimetic responses within rat mesenteric arteries: A novel role for K V 7.1 in shaping IP-receptor mediated relaxation. Br J Pharmacol 2021; 179:1338-1352. [PMID: 34766649 PMCID: PMC9340493 DOI: 10.1111/bph.15722] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 09/21/2021] [Accepted: 10/19/2021] [Indexed: 11/29/2022] Open
Abstract
Background and Purpose Prostacyclin mimetics express potent vasoactive effects via prostanoid receptors that are not unequivocally defined, as to date no study has considered sex as a factor. The aim of this study was to determine the contribution of IP and EP3 prostanoid receptors to prostacyclin mimetic iloprost‐mediated responses, whether KV7.1–5 channels represent downstream targets of selective prostacyclin‐IP‐receptor agonist MRE‐269 and the impact of the oestrus cycle on vascular reactivity. Experimental Approach Within second‐order mesenteric arteries from male and female Wistar rats, we determined (1) relative mRNA transcripts for EP1–4 (Ptger1–4), IP (Ptgi) and TXA2 (Tbxa) prostanoid receptors via RT‐qPCR; (2) the effect of iloprost, MRE‐269, isoprenaline and ML277 on precontracted arterial tone in the presence of inhibitors of prostanoid receptors, potassium channels and the molecular interference of KV7.1 via wire‐myograph; (3) oestrus cycle stage via histological changes in cervical cell preparations. Key Results Iloprost evoked a biphasic response in male mesenteric arteries, at concentrations ≤100 nmol·L−1 relaxing, then contracting the vessel at concentration ≥300 nmol·L−1, a process attributed to IP and EP3 receptors respectively. Secondary contraction was absent in the females, which was associated with a reduction in Ptger3. Pharmacological inhibition and molecular interference of KV7.1 significantly attenuated relaxations produced by the selective IP receptor agonist MRE‐269 in male and female Wistar in dioestrus/metoestrus, but not pro‐oestrus/oestrus. Conclusions and Implications Stark sexual dimorphisms in iloprost‐mediated vasoactive responses are present within mesenteric arteries. KV7.1 is implicated in IP receptor‐mediated vasorelaxation and is impaired by the oestrus cycle.
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Affiliation(s)
- Samuel N Baldwin
- Molecular and clinical sciences research institute, St George's university, Cranmer terrace, London
| | - Elizabeth A Forrester
- Molecular and clinical sciences research institute, St George's university, Cranmer terrace, London
| | - Lauren McEwan
- Molecular and clinical sciences research institute, St George's university, Cranmer terrace, London
| | - Iain A Greenwood
- Molecular and clinical sciences research institute, St George's university, Cranmer terrace, London
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13
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Jepps TA. Kv7 channel trafficking by the microtubule network in vascular smooth muscle. Acta Physiol (Oxf) 2021; 232:e13692. [PMID: 34021973 PMCID: PMC8365713 DOI: 10.1111/apha.13692] [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: 01/28/2021] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 12/17/2022]
Abstract
In arterial smooth muscle cells, changes in availability of integral membrane proteins influence the regulation of blood flow and blood pressure, which is critical for human health. However, the mechanisms that coordinate the trafficking and membrane expression of specific receptors and ion channels in vascular smooth muscle are poorly understood. In the vasculature, very little is known about microtubules, which form a road network upon which proteins can be transported to and from the cell membrane. This review article summarizes the impact of the microtubule network on arterial contractility, highlighting the importance of the network, with an emphasis on our recent findings regarding the trafficking of the voltage‐dependent Kv7 channels.
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Affiliation(s)
- Thomas A Jepps
- Vascular Biology Group Department of Biomedical Sciences University of Copenhagen Blegdamsvej 3 2200 Copenhagen N Denmark
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14
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Ottosson NE, Silverå Ejneby M, Wu X, Estrada-Mondragón A, Nilsson M, Karlsson U, Schupp M, Rognant S, Jepps TA, Konradsson P, Elinder F. Synthetic resin acid derivatives selectively open the hK V 7.2/7.3 channel and prevent epileptic seizures. Epilepsia 2021; 62:1744-1758. [PMID: 34085706 DOI: 10.1111/epi.16932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 04/19/2021] [Accepted: 05/03/2021] [Indexed: 01/10/2023]
Abstract
OBJECTIVE About one third of all patients with epilepsy have pharmacoresistant seizures. Thus there is a need for better pharmacological treatments. The human voltage-gated potassium (hKV ) channel hKV 7.2/7.3 is a validated antiseizure target for compounds that activate this channel. In a previous study we have shown that resin acid derivatives can activate the hKV 7.2/7.3 channel. In this study we investigated if these channel activators have the potential to be developed into a new type of antiseizure drug. Thus we examined their structure-activity relationships and the site of action on the hKV 7.2/7.3 channel, if they have unwanted cardiac and cardiovascular effects, and their potential antiseizure effect. METHODS Ion channels were expressed in Xenopus oocytes or mammalian cell lines and explored with two-electrode voltage-clamp or automated patch-clamp techniques. Unwanted vascular side effects were investigated with isometric tension recordings. Antiseizure activity was studied in an electrophysiological zebrafish-larvae model. RESULTS Fourteen resin acid derivatives were tested on hKV 7.2/7.3. The most efficient channel activators were halogenated and had a permanently negatively charged sulfonyl group. The compounds did not bind to the sites of other hKV 7.2/7.3 channel activators, retigabine, or ICA-069673. Instead, they interacted with the most extracellular gating charge of the S4 voltage-sensing helix, and the effects are consistent with an electrostatic mechanism. The compounds altered the voltage dependence of hKV 7.4, but in contrast to retigabine, there were no effects on the maximum conductance. Consistent with these data, the compounds had less smooth muscle-relaxing effect than retigabine. The compounds had almost no effect on the voltage dependence of hKV 11.1, hNaV 1.5, or hCaV 1.2, or on the amplitude of hKV 11.1. Finally, several resin acid derivatives had clear antiseizure effects in a zebrafish-larvae model. SIGNIFICANCE The described resin acid derivatives hold promise for new antiseizure medications, with reduced risk for adverse effects compared with retigabine.
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Affiliation(s)
- Nina E Ottosson
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Malin Silverå Ejneby
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Xiongyu Wu
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden
| | | | - Michelle Nilsson
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Urban Karlsson
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | | | - Salomé Rognant
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Andrew Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Peter Konradsson
- Department of Physics, Chemistry, and Biology, Linköping University, Linköping, Sweden
| | - Fredrik Elinder
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
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15
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Shvetsova AA, Gaynullina DK, Tarasova OS, Schubert R. Remodeling of Arterial Tone Regulation in Postnatal Development: Focus on Smooth Muscle Cell Potassium Channels. Int J Mol Sci 2021; 22:ijms22115413. [PMID: 34063769 PMCID: PMC8196626 DOI: 10.3390/ijms22115413] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/15/2021] [Accepted: 05/18/2021] [Indexed: 11/30/2022] Open
Abstract
Maturation of the cardiovascular system is associated with crucial structural and functional remodeling. Thickening of the arterial wall, maturation of the sympathetic innervation, and switching of the mechanisms of arterial contraction from calcium-independent to calcium-dependent occur during postnatal development. All these processes promote an almost doubling of blood pressure from the moment of birth to reaching adulthood. This review focuses on the developmental alterations of potassium channels functioning as key smooth muscle membrane potential determinants and, consequently, vascular tone regulators. We present evidence that the pattern of potassium channel contribution to vascular control changes from Kir2, Kv1, Kv7 and TASK-1 channels to BKCa channels with maturation. The differences in the contribution of potassium channels to vasomotor tone at different stages of postnatal life should be considered in treatment strategies of cardiovascular diseases associated with potassium channel malfunction.
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Affiliation(s)
- Anastasia A. Shvetsova
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; (D.K.G.); (O.S.T.)
- Correspondence:
| | - Dina K. Gaynullina
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; (D.K.G.); (O.S.T.)
- Department of Physiology, Russian National Research Medical University, 117997 Moscow, Russia
| | - Olga S. Tarasova
- Department of Human and Animal Physiology, Faculty of Biology, M.V. Lomonosov Moscow State University, 119234 Moscow, Russia; (D.K.G.); (O.S.T.)
- Laboratory of Exercise Physiology, State Research Center of the Russian Federation-Institute for Biomedical Problems, Russian Academy of Sciences, 123007 Moscow, Russia
| | - Rudolf Schubert
- Physiology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, 86159 Augsburg, Germany;
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16
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Abramavicius S, Petersen AG, Renaltan NS, Prat-Duran J, Torregrossa R, Stankevicius E, Whiteman M, Simonsen U. GYY4137 and Sodium Hydrogen Sulfide Relaxations Are Inhibited by L-Cysteine and K V7 Channel Blockers in Rat Small Mesenteric Arteries. Front Pharmacol 2021; 12:613989. [PMID: 33841145 PMCID: PMC8032876 DOI: 10.3389/fphar.2021.613989] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 02/12/2021] [Indexed: 01/23/2023] Open
Abstract
Donors of H2S may be beneficial in treating cardiovascular diseases where the plasma levels of H2S are decreased. Therefore, we investigated the mechanisms involved in relaxation of small arteries induced by GYY4137 [(4-methoxyphenyl)-morpholin-4-yl-sulfanylidene-sulfido-λ5-phosphane;morpholin-4-ium], which is considered a slow-releasing H2S donor. Sulfides were measured by use of 5,5′-dithiobis-(2-nitro benzoic acid), and small rat mesenteric arteries with internal diameters of 200–250 µm were mounted in microvascular myographs for isometric tension recordings. GYY4137 produced similar low levels of sulfides in the absence and the presence of arteries. In U46619-contracted small mesenteric arteries, GYY4137 (10−6–10–3 M) induced concentration-dependent relaxations, while a synthetic, sulfur-free, GYY4137 did not change the vascular tone. L-cysteine (10−6–10–3 M) induced only small relaxations reaching 24 ± 6% at 10–3 M. Premixing L-cysteine (10–3 M) with Na2S and GYY4137 decreased Na2S relaxation and abolished GYY4137 relaxation, an effect prevented by an nitric oxide (NO) synthase inhibitor, L-NAME (Nω-nitro-L-arginine methyl ester). In arteries without endothelium or in the presence of L-NAME, relaxation curves for GYY4137 were rightward shifted. High extracellular K+ concentrations decreased Na2S and abolished GYY4137 relaxation suggesting potassium channel-independent mechanisms are also involved Na2S relaxation while potassium channel activation is pivotal for GYY4137 relaxation in small arteries. Blockers of large-conductance calcium-activated (BKCa) and voltage-gated type 7 (KV7) potassium channels also inhibited GYY4137 relaxations. The present findings suggest that L-cysteine by reaction with Na2S and GYY4137 and formation of sulfides, inhibits relaxations by these compounds. The low rate of release of H2S species from GYY4137 is reflected by the different sensitivity of these relaxations towards high K+ concentration and potassium channel blockers compared with Na2S. The perspective is that the rate of release of sulfides plays an important for the effects of H2S salt vs. donors in small arteries, and hence for a beneficial effect of GYY4137 for treatment of cardiovascular disease.
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Affiliation(s)
- Silvijus Abramavicius
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark.,Institute of Physiology and Pharmacology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | - Asbjørn G Petersen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
| | - Nirthika S Renaltan
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
| | - Judit Prat-Duran
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
| | | | - Edgaras Stankevicius
- Institute of Cardiology, Lithuanian University of Health Sciences, Kaunas, Lithuania
| | | | - Ulf Simonsen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
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17
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The anti-diabetic drug alogliptin induces vasorelaxation via activation of Kv channels and SERCA pumps. Eur J Pharmacol 2021; 898:173991. [PMID: 33684451 DOI: 10.1016/j.ejphar.2021.173991] [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: 08/30/2020] [Revised: 02/24/2021] [Accepted: 02/28/2021] [Indexed: 11/22/2022]
Abstract
In the present study, we investigated the vasorelaxant effects of alogliptin, an oral antidiabetic drug in the dipeptidyl peptidase-4 (DPP-4) inhibitor class, using phenylephrine (Phe)-induced pre-contracted aortic rings. Alogliptin induced vasorelaxation in a dose-dependent manner. Pre-treatment with the voltage-dependent K+ (Kv) channel inhibitor 4-aminopyridine (4-AP) significantly decreased the vasorelaxant effect of alogliptin, whereas pre-treatment with the inwardly rectifying K+ (Kir) channel inhibitor Ba2+, ATP-sensitive K+ (KATP) channel inhibitor glibenclamide, and large-conductance Ca2+-activated K+ (BKCa) channel inhibitor paxilline did not alter the effects of alogliptin. Although pre-treatment with the Ca2+ channel inhibitor nifedipine did not affect the vasorelaxant effect of alogliptin, pre-treatment with the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) pump inhibitors thapsigargin and cyclopiazonic acid effectively attenuated the vasorelaxant response of alogliptin. Neither cGMP/protein kinase G (PKG)-related signaling pathway inhibitors (guanylyl cyclase inhibitor ODQ and PKG inhibitor KT 5823) nor cAMP/protein kinase A (PKA)-related signaling pathway inhibitors (adenylyl cyclase inhibitor SQ 22536 and PKA inhibitor KT 5720) reduced the vasorelaxant effect of alogliptin. Similarly, the vasorelaxant effect of alogliptin was not changed by endothelium removal or pre-treatment with the nitric oxide (NO) synthase inhibitor L-NAME or the small- and intermediate-conductance Ca2+-activated K+ (SKCa and IKCa) channel inhibitors apamin and TRAM-34. Based on these results, we suggest that alogliptin induced vasorelaxation in rabbit aortic smooth muscle by activating Kv channels and the SERCA pump independent of other K+ channels, cGMP/PKG-related or cAMP/PKA-related signaling pathways, and the endothelium.
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18
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Beck L, Pinilla E, Arcanjo DDR, Hernanz R, Prat-Duran J, Petersen AG, Köhler R, Sheykhzade M, Comerma-Steffensen S, Simonsen U. Pirfenidone Is a Vasodilator: Involvement of K V7 Channels in the Effect on Endothelium-Dependent Vasodilatation in Type-2 Diabetic Mice. Front Pharmacol 2021; 11:619152. [PMID: 33643042 PMCID: PMC7906977 DOI: 10.3389/fphar.2020.619152] [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: 10/19/2020] [Accepted: 12/30/2020] [Indexed: 12/27/2022] Open
Abstract
Endothelial cell dysfunction and fibrosis are associated with worsening of the prognosis in patients with cardiovascular disease. Pirfenidone has a direct antifibrotic effect, but vasodilatation may also contribute to the effects of pirfenidone. Therefore, in a first study we investigated the mechanisms involved in the relaxant effect of pirfenidone in rat intrapulmonary arteries and coronary arteries from normal mice. Then in a second study, we investigated whether pirfenidone restores endothelial function in the aorta and mesenteric arteries from diabetic animals. From 16–18-week old normal male C57BL/6 mice and normoglycemic (db/db+), and type 2 diabetic (db/db) male and female mice, arteries were mounted in microvascular isometric myographs for functional studies, and immunoblotting was performed. In rat pulmonary arteries and mouse coronary arteries, pirfenidone induced relaxations, which were inhibited in preparations without endothelium. In mouse coronary arteries, pirfenidone relaxation was inhibited in the presence of a nitric oxide (NO) synthase inhibitor, NG-nitro-l-arginine (L-NOARG), a blocker of large-conductance calcium-activated potassium channels (BKCa), iberiotoxin, and a blocker of KV7 channels, XE991. Patch clamp studies in vascular smooth muscle revealed pirfenidone increased iberiotoxin-sensitive current. In the aorta and mesenteric small arteries from diabetic db/db mice relaxations induced by the endothelium-dependent vasodilator, acetylcholine, were markedly reduced compared to db/db + mice. Pirfenidone enhanced the relaxations induced by acetylcholine in the aorta from diabetic male and female db/db mice. An opener of KV7 channels, flupirtine, had the same effect as pirfenidone. XE991 reduced the effect of pirfenidone and flupirtine and further reduced acetylcholine relaxations in the aorta. In the presence of iberiotoxin, pirfenidone still increased acetylcholine relaxation in aorta from db/db mice. Immunoblotting for KV7.4, KV7.5, and BKCa channel subunits were unaltered in aorta from db/db mice. Pirfenidone failed to improve acetylcholine relaxation in mesenteric arteries, and neither changed acetylcholine-induced transient decreases in blood pressure in db/db+ and db/db mice. In conclusion, pirfenidone vasodilates pulmonary and coronary arteries. In coronary arteries from normal mice, pirfenidone induces NO-dependent vasodilatation involving BKCa and KV7 channels. Pirfenidone improves endothelium-dependent vasodilatation in aorta from diabetic animals by a mechanism involving voltage-gated KV7 channels, a mechanism that may contribute to the antifibrotic effect of pirfenidone.
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Affiliation(s)
- Lilliana Beck
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
| | - Estéfano Pinilla
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark.,Department of Physiology, Faculty of Pharmacy, Universidad Complutense, Madrid, Spain
| | - Daniel Dias Rufino Arcanjo
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark.,Department of Biophysics and Physiology, Laboratory of Functional and Molecular Studies in Physiopharmacology, Federal University of Piauí, Teresina, Brazil
| | - Raquel Hernanz
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark.,Departamento de Ciencias Básicas de la Salud, Universidad Rey Juan Carlos, Alcorcón, Spain
| | - Judit Prat-Duran
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
| | - Asbjørn Graver Petersen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
| | - Ralf Köhler
- Aragón Agency for Research and Development (ARAID), Zaragoza, Spain
| | - Majid Sheykhzade
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Simon Comerma-Steffensen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark.,Department of Biomedical Sciences/Animal Physiology, Faculty of Veterinary, Central University of Venezuela, Maracay, Venezuela
| | - Ulf Simonsen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Aarhus University, Aarhus, Denmark
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19
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Baldwin SN, Sandow SL, Mondéjar-Parreño G, Stott JB, Greenwood IA. K V7 Channel Expression and Function Within Rat Mesenteric Endothelial Cells. Front Physiol 2020; 11:598779. [PMID: 33364977 PMCID: PMC7750541 DOI: 10.3389/fphys.2020.598779] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 11/13/2020] [Indexed: 01/04/2023] Open
Abstract
Background and Purpose: Arterial diameter is dictated by the contractile state of the vascular smooth muscle cells (VSMCs), which is modulated by direct and indirect inputs from endothelial cells (ECs). Modulators of KCNQ-encoded kV7 channels have considerable impact on arterial diameter and these channels are known to be expressed in VSMCs but not yet defined in ECs. However, expression of kV7 channels in ECs would add an extra level of vascular control. This study aims to characterize the expression and function of KV7 channels within rat mesenteric artery ECs. Experimental Approach: In rat mesenteric artery, KCNQ transcript and KV7 channel protein expression were determined via RT-qPCR, immunocytochemistry, immunohistochemistry and immunoelectron microscopy. Wire myography was used to determine vascular reactivity. Key Results: KCNQ transcript was identified in isolated ECs and VSMCs. KV7.1, KV7.4 and KV7.5 protein expression was determined in both isolated EC and VSMC and in whole vessels. Removal of ECs attenuated vasorelaxation to two structurally different KV7.2-5 activators S-1 and ML213. KIR2 blockers ML133, and BaCl2 also attenuated S-1 or ML213-mediated vasorelaxation in an endothelium-dependent process. KV7 inhibition attenuated receptor-dependent nitric oxide (NO)-mediated vasorelaxation to carbachol, but had no impact on relaxation to the NO donor, SNP. Conclusion and Implications: In rat mesenteric artery ECs, KV7.4 and KV7.5 channels are expressed, functionally interact with endothelial KIR2.x channels and contribute to endogenous eNOS-mediated relaxation. This study identifies KV7 channels as novel functional channels within rat mesenteric ECs and suggests that these channels are involved in NO release from the endothelium of these vessels.
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Affiliation(s)
- Samuel N Baldwin
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, London, United Kingdom
| | - Shaun L Sandow
- Biomedical Science, School of Health and Sports Science, University of the Sunshine Coast, Maroochydore, QLD, Australia
| | - Gema Mondéjar-Parreño
- Department of Pharmacology and Toxicology, School of Medicine, Complutense University of Madrid, Madrid, Spain
| | - Jennifer B Stott
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, London, United Kingdom
| | - Iain A Greenwood
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, London, United Kingdom
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20
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Tsai YM, Jones F, Mullen P, Porter KE, Steele D, Peers C, Gamper N. Vascular Kv7 channels control intracellular Ca 2+ dynamics in smooth muscle. Cell Calcium 2020; 92:102283. [PMID: 32950876 PMCID: PMC7695684 DOI: 10.1016/j.ceca.2020.102283] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 01/23/2023]
Abstract
Voltage-gated Kv7 (or KCNQ) channels control activity of excitable cells, including vascular smooth muscle cells (VSMCs), by setting their resting membrane potential and controlling other excitability parameters. Excitation-contraction coupling in muscle cells is mediated by Ca2+ but until now, the exact role of Kv7 channels in cytosolic Ca2+ dynamics in VSMCs has not been fully elucidated. We utilised microfluorimetry to investigate the impact of Kv7 channel activity on intracellular Ca2+ levels and electrical activity of rat A7r5 VSMCs and primary human internal mammary artery (IMA) SMCs. Both, direct (XE991) and G protein coupled receptor mediated (vasopressin, AVP) Kv7 channel inhibition induced robust Ca2+ oscillations, which were significantly reduced in the presence of Kv7 channel activator, retigabine, L-type Ca2+ channel inhibitor, nifedipine, or T-type Ca2+ channel inhibitor, NNC 55-0396, in A7r5 cells. Membrane potential measured using FluoVolt exhibited a slow depolarisation followed by a burst of sharp spikes in response to XE991; spikes were temporally correlated with Ca2+ oscillations. Phospholipase C inhibitor (edelfosine) reduced AVP-induced, but not XE991-induced Ca2+ oscillations. AVP and XE991 induced a large increase of [Ca2+]i in human IMA, which was also attenuated with retigabine, nifedipine and NNC 55-0396. RT-PCR, immunohistochemistry and electrophysiology suggested that Kv7.5 was the predominant Kv7 subunit in both rat and human arterial SMCs; CACNA1C (Cav1.2; L-type) and CACNA1 G (Cav3.1; T-type) were the most abundant voltage-gated Ca2+ channel gene transcripts in both types of VSMCs. This study establishes Kv7 channels as key regulators of Ca2+ signalling in VSMCs with Kv7.5 playing a dominant role.
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Affiliation(s)
- Yuan-Ming Tsai
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom; Division of Thoracic Surgery, Department of Surgery, Tri-Service General Hospital, National Defence Medical Centre, Taipei 11490, Taiwan.
| | - Frederick Jones
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Pierce Mullen
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Karen E Porter
- Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Derek Steele
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Chris Peers
- Leeds Institute of Cardiovascular and Metabolic Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Nikita Gamper
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, United Kingdom.
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21
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Dirkx N, Miceli F, Taglialatela M, Weckhuysen S. The Role of Kv7.2 in Neurodevelopment: Insights and Gaps in Our Understanding. Front Physiol 2020; 11:570588. [PMID: 33192566 PMCID: PMC7657400 DOI: 10.3389/fphys.2020.570588] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 09/07/2020] [Indexed: 11/13/2022] Open
Abstract
Kv7.2 subunits encoded by the KCNQ2 gene constitute a critical molecular component of the M-current, a subthreshold voltage-gated potassium current controlling neuronal excitability by dampening repetitive action potential firing. Pathogenic loss-of-function variants in KCNQ2 have been linked to epilepsy since 1998, and there is ample functional evidence showing that dysfunction of the channel indeed results in neuronal hyperexcitability. The recent description of individuals with severe developmental delay with or without seizures due to pathogenic variants in KCNQ2 (KCNQ2-encephalopathy) reveals that Kv7.2 channels also have an important role in neurodevelopment. Kv7.2 channels are expressed already very early in the developing brain when key developmental processes such as proliferation, differentiation, and synaptogenesis play a crucial role in brain morphogenesis and maturation. In this review, we will discuss the available evidence for a role of Kv7.2 channels in these neurodevelopmental processes, focusing in particular on insights derived from KCNQ2-related human phenotypes, from the spatio-temporal expression of Kv7.2 and other Kv7 family member, and from cellular and rodent models, highlighting critical gaps and research strategies to be implemented in the future. Lastly, we propose a model which divides the M-current activity in three different developmental stages, correlating with the cell characteristics during these particular periods in neuronal development, and how this can be linked with KCNQ2-related disorders. Understanding these mechanisms can create opportunities for new targeted therapies for KCNQ2-encephalopathy.
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Affiliation(s)
- Nina Dirkx
- Applied and Translational Neurogenomics Group, VIB Center for Molecular Neurology, Vlaams Instituut voor Biotechnologie, Antwerp, Belgium
| | - Francesco Miceli
- Section of Pharmacology, Department of Neuroscience, University of Naples Federico II, Naples, Italy
| | - Maurizio Taglialatela
- Section of Pharmacology, Department of Neuroscience, University of Naples Federico II, Naples, Italy
| | - Sarah Weckhuysen
- Applied and Translational Neurogenomics Group, VIB Center for Molecular Neurology, Vlaams Instituut voor Biotechnologie, Antwerp, Belgium.,Department of Translational Neurosciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.,Department of Neurology, Antwerp University Hospital, Antwerp, Belgium
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22
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Lee JE, Park CH, Kang H, Ko J, Cho S, Woo J, Chae MR, Lee SW, Kim SJ, Kim J, So I. The agonistic action of URO-K10 on Kv7.4 and 7.5 channels is attenuated by co-expression of KCNE4 ancillary subunit. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2020; 24:503-516. [PMID: 33093272 PMCID: PMC7585595 DOI: 10.4196/kjpp.2020.24.6.503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/07/2020] [Accepted: 10/07/2020] [Indexed: 12/02/2022]
Abstract
KCNQ family constitutes slowly-activating potassium channels among voltage-gated potassium channel superfamily. Recent studies suggested that KCNQ4 and 5 channels are abundantly expressed in smooth muscle cells, especially in lower urinary tract including corpus cavernosum and that both channels can exert membrane stabilizing effect in the tissues. In this article, we examined the electrophysiological characteristics of overexpressed KCNQ4, 5 channels in HEK293 cells with recently developed KCNQ-specific agonist. With submicromolar EC50, the drug not only increased the open probability of KCNQ4 channel but also increased slope conductance of the channel. The overall effect of the drug in whole-cell configuration was to increase maximal whole-cell conductance, to prolongate the activation process, and left-shift of the activation curve. The agonistic action of the drug, however, was highly attenuated by the co-expression of one of the β ancillary subunits of KCNQ family, KCNE4. Strong in vitro interactions between KCNQ4, 5 and KCNE4 were found through Foster Resonance Energy Transfer and co-immunoprecipitation. Although the expression levels of both KCNQ4 and KCNE4 are high in mesenteric arterial smooth muscle cells, we found that 1 μM of the agonist was sufficient to almost completely relax phenylephrine-induced contraction of the muscle strip. Significant expression of KCNQ4 and KCNE4 in corpus cavernosum together with high tonic contractility of the tissue grants highly promising relaxational effect of the KCNQ-specific agonist in the tissue.
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Affiliation(s)
- Jung Eun Lee
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Christine Haewon Park
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Hana Kang
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Juyeon Ko
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Suhan Cho
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - JooHan Woo
- Department of Physiology, Dongguk University College of Medicine, Gyeongju 38066, Korea
| | - Mee Ree Chae
- Department of Urology, Samsung Medical Center, Seoul 06351, Korea
| | - Sung Won Lee
- Department of Urology, Samsung Medical Center, Seoul 06351, Korea
| | - Sung Joon Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Jinsung Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
| | - Insuk So
- Department of Physiology, Seoul National University College of Medicine, Seoul 03080, Korea
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23
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Mondéjar-Parreño G, Barreira B, Callejo M, Morales-Cano D, Barrese V, Esquivel-Ruiz S, Olivencia MA, Macías M, Moreno L, Greenwood IA, Perez-Vizcaino F, Cogolludo A. Uncovered Contribution of Kv7 Channels to Pulmonary Vascular Tone in Pulmonary Arterial Hypertension. Hypertension 2020; 76:1134-1146. [DOI: 10.1161/hypertensionaha.120.15221] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
K
+
channels play a fundamental role regulating membrane potential of pulmonary artery (PA) smooth muscle cells and their impairment is a common feature in pulmonary arterial hypertension (PAH). K
+
voltage-gated channel subfamily Q (
KCNQ1-5
) or Kv7 channels and their regulatory subunits subfamily E (KCNE) regulatory subunits are known to regulate vascular tone, but whether Kv7 channel function is impaired in PAH and how this can affect the rationale for targeting Kv7 channels in PAH remains unknown. Here, we have studied the role of Kv7/KCNE subunits in rat PA and their possible alteration in PAH. Using the patch-clamp technique, we found that the total K
+
current is reduced in PA smooth muscle cells from pulmonary hypertension animals (SU5416 plus hypoxia) and Kv7 currents made a higher contribution to the net K
+
current. Likewise, enhanced vascular responses to Kv7 channel modulators were found in pulmonary hypertension rats. Accordingly, KCNE4 subunit was highly upregulated in lungs from pulmonary hypertension animals and patients. Additionally, Kv7 channel activity was enhanced in the presence of Kv1.5 and TASK-1 channel inhibitors and this was associated with an increased KCNE4 membrane abundance. Compared with systemic arteries, PA showed a poor response to Kv7 channel modulators which was associated with reduced expression and membrane abundance of Kv7.4 and KCNE4. Our data indicate that Kv7 channel function is preserved and KCNE4 is upregulated in PAH. Therefore, compared with other downregulated channels, the contribution of Kv7 channels is increased in PAH resulting in an enhanced sensitivity to Kv7 channel modulators. This study provides insight into the potential usefulness of targeting Kv7 channels in PAH.
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Affiliation(s)
- Gema Mondéjar-Parreño
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Bianca Barreira
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - María Callejo
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Daniel Morales-Cano
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain (D.M.-C.)
| | - Vincenzo Barrese
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George’s University of London, United Kingdom (V.B., I.A.G.)
- Department of Neuroscience, Reproductive Sciences and Dentistry, University of Naples Federico II, Naples, Italy (V.B.)
| | - Sergio Esquivel-Ruiz
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Miguel A. Olivencia
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Miguel Macías
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Laura Moreno
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Iain A. Greenwood
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George’s University of London, United Kingdom (V.B., I.A.G.)
| | - Francisco Perez-Vizcaino
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
| | - Angel Cogolludo
- From the Departamento de Farmacología y Toxicología. Facultad de Medicina, Universidad Complutense de Madrid, Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Ciber Enfermedades Respiratorias (Ciberes), Spain (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
- Instituto de Investigación Sanitaria Gregorio Marañón (IISGM) (G.M.-P., B.B., M.C., S.E.-R., M.A.O., M.M., L.M., F.P.-V., A.C.)
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24
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Turzo M, Spöhr FA, Felix L, Weigand MA, Busch CJ. Kv7 channel inhibition increases hypoxic pulmonary vasoconstriction in endotoxemic mouse lungs. Exp Lung Res 2020; 46:363-375. [PMID: 32945215 DOI: 10.1080/01902148.2020.1818888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE Hypoxic pulmonary vasoconstriction (HPV) regulates regional pulmonary blood flow in order to match regional ventilation to preserve arterial oxygenation. HPV is impaired in patients with sepsis or acute respiratory distress syndrome (ARDS). Endotoxemic mice show reduced HPV and recent evidence suggests a central role of voltage gated potassium channel 7 (Kv7) in regulating HPV. Therefore, we tested the hypothesis if Kv7 is induced and inhibition of Kv7 increases HPV in endotoxemia. MATERIALS AND METHODS Isolated lungs of LPS-pretreated and untreated animals were perfused with and without specific inhibitors of Kv7 (linopirdine (LI) 0, 0.1, 1 and 10 µM) or Kv7.1 (HMR1556 100 nM). Pulmonary artery pressure (PAP) during normoxic (FiO2 0.21) as well as hypoxic (FiO2 0.01) ventilation were obtained. Expressions of Kv7 composing (KCNQ1-5) as well as auxiliary subunits (KCNE1-5) were measured in mouse lungs with and without endotoxemia. RESULTS HPV was impaired in lungs from LPS mice (16 ± 7% vs 105 ± 13% control, p < 0.05). Perfusion of control lungs with 10 µM LI or 100 nM HMR1556 did not affect HPV (LI 105 ± 12% vs 105 ± 13% vehicle, HMR1556 100 ± 6% vs 98 ± 26%, P = NS). In LPS mice perfusion with 10 µM LI (74.2 ± 7% vs. 16 ± 7% vehicle, P < 0.05) or HMR1556 100 nM augmented HPV (74 ± 28% vs. 15 ± 17% vehicle, P < 0.05). KCNQ1, 4 and 5 gene- and protein expressions as well as KCNE1, 2 and 4 gene expressions were unaltered in endotoxemic lungs. KCNE3 gene and protein expressions were increased in lungs of LPS treated mice (3.1 ± 1.3-fold and 1.8 ± 0.3-fold, respectively, P < 0.05 for both). CONCLUSIONS Endotoxemia does not alter KCNQ1, 4 and 5 gene and protein expressions but increases pulmonary KCNE3 gene and protein expression. In isolated perfused endotoxemic mouse lungs, perfusion with 10 µM LI or 100 nM HMR1556 augments HPV.
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Affiliation(s)
- Maurizio Turzo
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Fabian A Spöhr
- Department of Anesthesiology, Sana Kliniken, Stuttgart, Germany.,Department of Anesthesiology and Intensive Care Medicine, University of Cologne, Cologne, Germany
| | - Lasitschka Felix
- Institute of Pathology, Heidelberg University Hospital, Heidelberg, Germany
| | - Markus A Weigand
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Cornelius J Busch
- Department of Anesthesiology, Heidelberg University Hospital, Heidelberg, Germany
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25
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Diniz AFA, Ferreira RC, de Souza ILL, da Silva BA. Ionic Channels as Potential Therapeutic Targets for Erectile Dysfunction: A Review. Front Pharmacol 2020; 11:1120. [PMID: 32848741 PMCID: PMC7396897 DOI: 10.3389/fphar.2020.01120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 07/10/2020] [Indexed: 12/12/2022] Open
Abstract
Erectile dysfunction (ED) is a prevalent condition, especially in men over 40 years old, characterized by the inability to obtain and/or maintain penile erection sufficient for satisfactory sexual intercourse. Several psychological and/or organic factors are involved in the etiopathogenesis of ED. In this context, we gathered evidence of the involvement of Large-conductance, Ca2+-activated K+ channels (BKCa), Small-conductance, Ca2+-activated K+ channels (SKCa), KCNQ-encoded voltage-dependent K+ channels (KV7), Transient Receptor Potential channels (TRP), and Calcium-activated Chloride channels (CaCC) dysfunctions on ED. In addition, the use of modulating agents of these channels are involved in relaxation of the cavernous smooth muscle cell and, consequent penile erection, suggesting that these channels are promising therapeutic targets for the treatment of erectile dysfunction.
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Affiliation(s)
- Anderson Fellyp Avelino Diniz
- Programa de Pós-Graduação em Produtos Naturais e Sintéticos Bioativos, Universidade Federal da Paraíba, João Pessoa, Brazil
| | - Rafael Carlos Ferreira
- Programa de Pós-Graduação em Produtos Naturais e Sintéticos Bioativos, Universidade Federal da Paraíba, João Pessoa, Brazil
| | - Iara Leão Luna de Souza
- Departamento de Ciências Biológicas e da Saúde, Universidade Estadual de Roraima, Boa Vista, Brazil
| | - Bagnólia Araújo da Silva
- Programa de Pós-Graduação em Produtos Naturais e Sintéticos Bioativos, Universidade Federal da Paraíba, João Pessoa, Brazil
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26
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Redford KE, Abbott GW. The ubiquitous flavonoid quercetin is an atypical KCNQ potassium channel activator. Commun Biol 2020; 3:356. [PMID: 32641720 PMCID: PMC7343821 DOI: 10.1038/s42003-020-1089-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 06/18/2020] [Indexed: 12/11/2022] Open
Abstract
Many commonly consumed plants are used as folk medicines, often with unclear molecular mechanisms. Recent studies uncovered the ubiquitous and influential KCNQ family of voltage-gated potassium (Kv) channels as a therapeutic target for several medicinal plant compounds. Capers - immature flower buds of Capparis spinosa - have been consumed for food and medicinal purposes for millennia. Here, we show that caper extract hyperpolarizes cells expressing KCNQ1 or KCNQ2/3 Kv channels. Capers are the richest known natural source of quercetin, the most consumed dietary flavonoid. Quercetin potentiated KCNQ1/KCNE1, KCNQ2/3 and KCNQ4 currents but, unusually, not KCNQ5. Strikingly, quercetin augmented both activation and inactivation of KCNQ1, via a unique KCNQ activation mechanism involving sites atop the voltage sensor and in the pore. The findings uncover a novel potential molecular basis for therapeutic effects of quercetin-rich foods and a new chemical space for atypical modes of KCNQ channel modulation. Kaitlyn E. Redford and Geoffrey W. Abbott show that quercetin, a flavonoid highly expressed in capers, potentiates KCNQ currents to varying degrees depending on the subunit composition of the channel complex. By combining in silico docking, mutagenesis, and electrophysiology they show that this flavonoid can bind KCNQ channels atop the voltage sensor and within the pore module, highlighting an atypical mode of channel modulation.
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Affiliation(s)
- Kaitlyn E Redford
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, USA.
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27
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Abbott GW. KCNQs: Ligand- and Voltage-Gated Potassium Channels. Front Physiol 2020; 11:583. [PMID: 32655402 PMCID: PMC7324551 DOI: 10.3389/fphys.2020.00583] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 05/11/2020] [Indexed: 12/26/2022] Open
Abstract
Voltage-gated potassium (Kv) channels in the KCNQ (Kv7) family are essential features of a broad range of excitable and non-excitable cell types and are found in organisms ranging from Hydra vulgaris to Homo sapiens. Although they are firmly in the superfamily of S4 domain-bearing voltage-sensing ion channels, KCNQ channels are highly sensitive to a range of endogenous and exogenous small molecules that act directly on the pore, the voltage-sensing domain, or the interface between the two. The focus of this review is regulation of KCNQs by direct binding of neurotransmitters and metabolites from both animals and plants and the role of the latter in the effects of plants consumed for food and as traditional folk medicines. The conceptual question arises: Are KCNQs voltage-gated channels that are also sensitive to ligands or ligand-gated channels that are also sensitive to voltage?
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Affiliation(s)
- Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, Irvine, CA, United States
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28
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van der Horst J, Manville RW, Hayes K, Thomsen MB, Abbott GW, Jepps TA. Acetaminophen (Paracetamol) Metabolites Induce Vasodilation and Hypotension by Activating Kv7 Potassium Channels Directly and Indirectly. Arterioscler Thromb Vasc Biol 2020; 40:1207-1219. [PMID: 32188278 DOI: 10.1161/atvbaha.120.313997] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Intravenous acetaminophen/paracetamol (APAP) is well documented to cause hypotension. Since the patients receiving intravenous APAP are usually critically ill, any severe hemodynamic changes, as with those associated with APAP, can be life-threatening. The mechanism underlying this dangerous iatrogenic effect of APAP was unknown. Approach and Results: Here, we show that intravenous APAP caused transient hypotension in rats, which was attenuated by the Kv7 channel blocker, linopirdine. APAP metabolite N-acetyl-p-benzoquinone imine caused vasodilatation of rat mesenteric arteries ex vivo. This vasodilatation was sensitive to linopirdine and also the calcitonin gene-related peptide antagonist, BIBN 4096. Further investigation revealed N-acetyl-p-benzoquinone imine stimulates calcitonin gene-related peptide release from perivascular nerves, causing a cAMP-dependent activation of Kv7 channels. We also show that N-acetyl-p-benzoquinone imine enhances Kv7.4 and Kv7.5 channels overexpressed in oocytes, suggesting that it can activate Kv7.4 and Kv7.5 channels directly, to elicit vasodilatation. CONCLUSIONS Direct and indirect activation of Kv7 channels by the APAP metabolite N-acetyl-p-benzoquinone imine decreases arterial tone, which can lead to a drop in blood pressure. Our findings provide a molecular mechanism and potential preventive intervention for the clinical phenomenon of intravenous APAP-dependent transient hypotension.
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Affiliation(s)
- Jennifer van der Horst
- From the Vascular Biology Group, Department of Biomedical Science (J.v.d.H., K.H., T.A.J.), University of Copenhagen, Denmark
| | - Rian W Manville
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine (R.W.M., G.W.A.)
| | - Katie Hayes
- From the Vascular Biology Group, Department of Biomedical Science (J.v.d.H., K.H., T.A.J.), University of Copenhagen, Denmark
| | - Morten B Thomsen
- Cardiac Electrophysiology Group, Department of Biomedical Science (M.B.T.), University of Copenhagen, Denmark
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine (R.W.M., G.W.A.)
| | - Thomas A Jepps
- From the Vascular Biology Group, Department of Biomedical Science (J.v.d.H., K.H., T.A.J.), University of Copenhagen, Denmark
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29
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Zavaritskaya O, Dudem S, Ma D, Rabab KE, Albrecht S, Tsvetkov D, Kassmann M, Thornbury K, Mladenov M, Kammermeier C, Sergeant G, Mullins N, Wouappi O, Wurm H, Kannt A, Gollasch M, Hollywood MA, Schubert R. Vasodilation of rat skeletal muscle arteries by the novel BK channel opener GoSlo is mediated by the simultaneous activation of BK and K v 7 channels. Br J Pharmacol 2020; 177:1164-1186. [PMID: 31658366 PMCID: PMC7042121 DOI: 10.1111/bph.14910] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 09/27/2019] [Accepted: 10/01/2019] [Indexed: 01/17/2023] Open
Abstract
Background and Purpose BK channels play important roles in various physiological and pathophysiological processes and thus have been the target of several drug development programmes focused on creating new efficacious BK channel openers, such as the GoSlo‐SR compounds. However, the effect of GoSlo‐SR compounds on vascular smooth muscle has not been studied. Therefore, we tested the hypothesis that GoSlo‐SR compounds dilate arteries exclusively by activating BK channels. Experimental Approach Experiments were performed on rat Gracilis muscle, saphenous, mesenteric and tail arteries using isobaric and isometric myography, sharp microelectrodes, digital droplet PCR and the patch‐clamp technique. Key Results GoSlo‐SR compounds dilated isobaric and relaxed and hyperpolarised isometric vessel preparations and their effects were abolished after (a) functionally eliminating K+ channels by pre‐constriction with 50 mM KCl or (b) blocking all K+ channels known to be expressed in vascular smooth muscle. However, these effects were not blocked when BK channels were inhibited. Surprisingly, the Kv7 channel inhibitor XE991 reduced their effects considerably, but neither Kv1 nor Kv2 channel blockers altered the inhibitory effects of GoSlo‐SR. However, the combined blockade of BK and Kv7 channels abolished the GoSlo‐SR‐induced relaxation. GoSlo‐SR compounds also activated Kv7.4 and Kv7.5 channels expressed in HEK 293 cells. Conclusion and Implications This study shows that GoSlo‐SR compounds are effective relaxants in vascular smooth muscle and mediate their effects by a combined activation of BK and Kv7.4/Kv7.5 channels. Activation of Kv1, Kv2 or Kv7.1 channels or other vasodilator pathways seems not to be involved.
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Affiliation(s)
- Olga Zavaritskaya
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Srikanth Dudem
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Dongyu Ma
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.,Department of Cardiology, The First Affiliated Hospital of Anhui Medical University, Anhui, China
| | - Kaneez E Rabab
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Sarah Albrecht
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Dmitry Tsvetkov
- Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany
| | - Mario Kassmann
- Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany
| | - Keith Thornbury
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland.,Ion Channel Biotechnology Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Mitko Mladenov
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.,Institute of Biology, Faculty of Natural Sciences and Mathematics, Sts. Cyril and Methodius, University of Skopje, Skopje, Macedonia.,Department of Fundamental and Applied Physiology, Russian National Research Medical University, Moscow, Russia
| | - Claire Kammermeier
- Sanofi Diabetes Research, Industriepark Hoechst, Frankfurt am Main, Germany
| | - Gerard Sergeant
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland.,Ion Channel Biotechnology Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Nicholas Mullins
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Ornella Wouappi
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Hannah Wurm
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Aimo Kannt
- Sanofi Diabetes Research, Industriepark Hoechst, Frankfurt am Main, Germany.,Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany
| | - Maik Gollasch
- Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany
| | - Mark A Hollywood
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland.,Ion Channel Biotechnology Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Rudolf Schubert
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.,Faculty of Medicine, Department of Physiology, Augsburg University, Augsburg, Germany
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Characterization and functional roles of KCNQ-encoded voltage-gated potassium (Kv7) channels in human corpus cavernosum smooth muscle. Pflugers Arch 2020; 472:89-102. [PMID: 31919767 DOI: 10.1007/s00424-019-02343-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 12/12/2019] [Accepted: 12/26/2019] [Indexed: 12/23/2022]
Abstract
The group of KCNQ-encoded voltage-gated potassium (Kv7) channels includes five family members (Kv7.1-7.5). We examined the molecular expression and functional roles of Kv7 channels in corporal smooth muscle (CSM). Isolated rabbit CSM strips were mounted in an organ bath system to characterize Kv7 channels during CSM relaxation. Intracellular Ca2+ levels were measured in the CSM using the Ca2+ dye Fluo-4 AM. The expression of the KCNQ1-5 (the encoding genes for Kv7.1-7.5) and KCNE1-5 subtypes was determined by quantitative real-time PCR. Electrophysiological recordings and an in situ proximity ligation assay (PLA) were also performed. ML213 (a Kv7.2/7.4/7.5 activator) exhibited the most potent relaxation effect. XE911 (a Kv7.1-7.5 blocker) significantly inhibited the relaxation caused by ML213. Removal of the endothelium from the CSM did not affect the relaxation effect of ML213. H-89 (a protein kinase A inhibitor) and ESI-09 (an exchange protein directly activated by cAMP inhibitor) significantly inhibited ML213-induced relaxation (H-89: 31.3%; ESI-09: 52.7%). XE991 significantly increased basal [Ca2+]i in hCSM cells. KCNQ4 (the Kv7.4-encoding gene) and KCNE4 in CSM were the most abundantly expressed subtypes in humans and rats, respectively. KCNQ4 and KCNE4 expression was significantly decreased in diabetes mellitus rats. ML213 significantly increased the outward current amplitude. XE991 inhibited the ML213-induced outward currents. ML213 hyperpolarized the hCSM cell membrane potential. Subsequent addition of XE991 completely reversed the ML213-induced hyperpolarizing effects. A combination of Kv7.4 and Kv7.5 antibodies generated a strong PLA signal. We found that the Kv7.4 channel is a potential target for ED treatment.
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Corydon KK, Matchkov V, Fais R, Abramochkin D, Hedegaard ER, Comerma-Steffensen S, Simonsen U. Effect of ischemic preconditioning and a Kv7 channel blocker on cardiac ischemia-reperfusion injury in rats. Eur J Pharmacol 2019; 866:172820. [PMID: 31760069 DOI: 10.1016/j.ejphar.2019.172820] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/19/2019] [Accepted: 11/20/2019] [Indexed: 12/30/2022]
Abstract
Recently, we found cardioprotective effects of ischemic preconditioning (IPC), and from a blocker of KCNQ voltage-gated K+ channels (KV7), XE991 (10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone), in isolated rat hearts. The purpose of the present study was to investigate the cardiovascular effects of IPC and XE991 and whether they are cardioprotective in intact rats. In conscious rats, we measured the effect of the KV7 channel blocker XE991 on heart rate and blood pressure by use of telemetry. In anesthetized rats, cardiac ischemia was induced by occluding the left coronary artery, and the animals received IPC (2 × 5 min of occlusion), XE991, or a combination. After a 2 h reperfusion period, the hearts were excised, and the area at risk and infarct size were determined. In both anesthetized and conscious rats, XE991 increased blood pressure, and the highest dose (7.5 mg/kg) of XE991 also increased heart rate, and 44% of conscious rats died. XE991 induced marked changes in the electrocardiogram (e.g., increased PR interval and prolonged QTC interval) without changing cardiac action potentials. The infarct size to area at risk ratio was reduced from 53 ± 2% (n = 8) in the vehicle compared to 36 ± 3% in the IPC group (P < 0.05, n = 9). XE991 (0.75 mg/kg) treatment alone or on top of IPC failed to reduce myocardial infarct size. Similar to the effect in isolated hearts, locally applied IPC was cardioprotective in intact animals exposed to ischemia-reperfusion. Systemic administration of XE991 failed to protect the heart against ischemia-reperfusion injury suggesting effects on the autonomic nervous system counteracting the cardioprotection in intact animals.
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Affiliation(s)
- Krestine Kjeldsen Corydon
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology and Physiology, Aarhus University, Wilhelm Meyers Allé 4, 8000, Aarhus C, Denmark
| | - Vladimir Matchkov
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology and Physiology, Aarhus University, Wilhelm Meyers Allé 4, 8000, Aarhus C, Denmark
| | - Rafael Fais
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology and Physiology, Aarhus University, Wilhelm Meyers Allé 4, 8000, Aarhus C, Denmark; Department of Pharmacology, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, São Paulo, Brazil
| | - Denis Abramochkin
- Department of Human and Animal Physiology, Biological Faculty, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia; Ural Federal University, Mira 19, Ekaterinburg, Russia; Department of Physiology, Russian National Research Medical University, Ostrovityanova 1, Moscow, Russia
| | - Elise Røge Hedegaard
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology and Physiology, Aarhus University, Wilhelm Meyers Allé 4, 8000, Aarhus C, Denmark
| | - Simon Comerma-Steffensen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology and Physiology, Aarhus University, Wilhelm Meyers Allé 4, 8000, Aarhus C, Denmark; Department of Biomedical Sciences/Animal Physiology, Veterinary Faculty, Central University of Venezuela, Maracay, Aragua, Venezuela
| | - Ulf Simonsen
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology and Physiology, Aarhus University, Wilhelm Meyers Allé 4, 8000, Aarhus C, Denmark.
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Manville RW, Abbott GW. Cilantro leaf harbors a potent potassium channel-activating anticonvulsant. FASEB J 2019; 33:11349-11363. [PMID: 31311306 PMCID: PMC6766653 DOI: 10.1096/fj.201900485r] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 06/25/2019] [Indexed: 11/11/2022]
Abstract
Herbs have a long history of use as folk medicine anticonvulsants, yet the underlying mechanisms often remain unknown. Neuronal voltage-gated potassium channel subfamily Q (KCNQ) dysfunction can cause severe epileptic encephalopathies that are resistant to modern anticonvulsants. Here we report that cilantro (Coriandrum sativum), a widely used culinary herb that also exhibits antiepileptic and other therapeutic activities, is a highly potent KCNQ channel activator. Screening of cilantro leaf metabolites revealed that one, the long-chain fatty aldehyde (E)-2-dodecenal, activates multiple KCNQs, including the predominant neuronal isoform, KCNQ2/KCNQ3 [half maximal effective concentration (EC50), 60 ± 20 nM], and the predominant cardiac isoform, KCNQ1 in complexes with the type I transmembrane ancillary subunit (KCNE1) (EC50, 260 ± 100 nM). (E)-2-dodecenal also recapitulated the anticonvulsant action of cilantro, delaying pentylene tetrazole-induced seizures. In silico docking and mutagenesis studies identified the (E)-2-dodecenal binding site, juxtaposed between residues on the KCNQ S5 transmembrane segment and S4-5 linker. The results provide a molecular basis for the therapeutic actions of cilantro and indicate that this ubiquitous culinary herb is surprisingly influential upon clinically important KCNQ channels.-Manville, R. W., Abbott, G. W. Cilantro leaf harbors a potent potassium channel-activating anticonvulsant.
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Affiliation(s)
- Rían W. Manville
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California–Irvine, Irvine, California, USA
| | - Geoffrey W. Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California–Irvine, Irvine, California, USA
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KCNQ5 activation is a unifying molecular mechanism shared by genetically and culturally diverse botanical hypotensive folk medicines. Proc Natl Acad Sci U S A 2019; 116:21236-21245. [PMID: 31570602 DOI: 10.1073/pnas.1907511116] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Botanical folk medicines have been used throughout human history to treat common disorders such as hypertension, often with unknown underlying mechanisms. Here, we discovered that hypotensive folk medicines from a genetically diverse range of plant species each selectively activated the vascular-expressed KCNQ5 potassium channel, a feature lacking in the modern synthetic pharmacopeia, whereas nonhypotensive plant extracts did not. Analyzing constituents of the hypotensive Sophora flavescens root, we found that the quinolizidine alkaloid aloperine is a KCNQ-dependent vasorelaxant that potently and isoform-selectively activates KCNQ5 by binding near the foot of the channel voltage sensor. Our findings reveal that KCNQ5-selective activation is a defining molecular mechanistic signature of genetically diverse traditional botanical hypotensives, transcending plant genus and human cultural boundaries. Discovery of botanical KCNQ5-selective potassium channel openers may enable future targeted therapies for diseases including hypertension and KCNQ5 loss-of-function encephalopathy.
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34
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Mondéjar-Parreño G, Moral-Sanz J, Barreira B, De la Cruz A, Gonzalez T, Callejo M, Esquivel-Ruiz S, Morales-Cano D, Moreno L, Valenzuela C, Perez-Vizcaino F, Cogolludo A. Activation of K v 7 channels as a novel mechanism for NO/cGMP-induced pulmonary vasodilation. Br J Pharmacol 2019; 176:2131-2145. [PMID: 30883701 DOI: 10.1111/bph.14662] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 02/08/2019] [Accepted: 02/13/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND AND PURPOSE The NO/cGMP pathway represents a major physiological signalling controlling tone in pulmonary arteries (PA), and drugs activating this pathway are used to treat pulmonary arterial hypertension. Kv channels expressed in PA smooth muscle cells (PASMCs) are key determinants of vascular tone. We aimed to analyse the contribution of Kv 1.5 and Kv 7 channels in the electrophysiological and vasodilating effects evoked by NO donors and the GC stimulator riociguat in PA. EXPERIMENTAL APPROACH Kv currents were recorded in isolated rat PASMCs using the patch-clamp technique. Vascular reactivity was assessed in a wire myograph. KEY RESULTS The NO donors diethylamine NONOate diethylammonium (DEA-NO) and sodium nitroprusside hyperpolarized the membrane potential and induced a bimodal effect on Kv currents (augmenting the current between -40 and -10 mV and decreasing it at more depolarized potentials). The hyperpolarization and the enhancement of the current were suppressed by Kv 7 channel inhibitors and by the GC inhibitor ODQ but preserved when Kv 1.5 channels were inhibited. Additionally, DEA-NO enhanced Kv 7.5 currents in COS7 cells expressing the KCNQ5 gene. Riociguat increased Kv currents at all potentials ≥-40 mV and induced membrane hyperpolarization. Both effects were prevented by Kv 7 inhibition. Likewise, PA relaxation induced by NO donors and riociguat was attenuated by Kv 7 inhibitors. CONCLUSIONS AND IMPLICATIONS NO donors and riociguat enhance Kv 7 currents, leading to PASMC hyperpolarization. This mechanism contributes to NO/cGMP-induced PA vasodilation. Our study identifies Kv 7 channels as a novel mechanism of action of vasodilator drugs used in the treatment of pulmonary arterial hypertension.
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Affiliation(s)
- Gema Mondéjar-Parreño
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Javier Moral-Sanz
- Centres for Discovery Brain Sciences and Cardiovascular Science, College of Medicine and Veterinary Medicine, University of Edinburgh, Edinburgh, UK
| | - Bianca Barreira
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Alicia De la Cruz
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain.,CIBER Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Teresa Gonzalez
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain.,CIBER Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain.,Department of Biochemistry, School of Medicine, Universidad Autónoma de Madrid, Hospital La Paz Institute for Health Research (IdiPAZ), Madrid, Spain
| | - Maria Callejo
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Sergio Esquivel-Ruiz
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Daniel Morales-Cano
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Laura Moreno
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Carmen Valenzuela
- Instituto de Investigaciones Biomédicas "Alberto Sols" CSIC-UAM, Madrid, Spain.,CIBER Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Francisco Perez-Vizcaino
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Angel Cogolludo
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.,Ciber Enfermedades Respiratorias (CIBERES), Madrid, Spain
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Shvetsova AA, Gaynullina DK, Tarasova OS, Schubert R. Negative feedback regulation of vasocontraction by potassium channels in 10- to 15-day-old rats: Dominating role of K v 7 channels. Acta Physiol (Oxf) 2019; 225:e13176. [PMID: 30136434 DOI: 10.1111/apha.13176] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 08/11/2018] [Accepted: 08/20/2018] [Indexed: 12/26/2022]
Abstract
AIM Potassium channels are key regulators of smooth muscle membrane potential and arterial tone. However, the roles of potassium channels in vascular tone regulation in the systemic circulation during early postnatal development are poorly understood. Therefore, this study tested the hypothesis that the negative feedback regulation of vasocontraction by potassium channels changes during maturation. METHODS Experiments were performed on endothelium-denuded saphenous arteries from 10- to 15-day-old and 2- to 3-month-old male rats. Isometric force and membrane potential were recorded using wire myography and the sharp microelectrode technique respectively; mRNA and protein contents were determined by qPCR and Western blotting. RESULTS The effects of Kv 1, Kir and Kv 7 channel blockers (DPO-1, BaCl2 , XE991) on methoxamine-induced contraction were larger in arteries of 10- to 15-day-old compared to 2- to 3-month-old animals. In contrast, the BKC a channel blocker iberiotoxin had a stronger influence in 2- to 3- month-old rats. The effects of KATP and Kv 2 channel blockers (glibenclamide, stromatoxin) were not pronounced at both ages. The larger influence of Kv 7 and Kir channel blockade on arterial contraction in 10- to 15-day-old rats was associated with more prominent smooth muscle depolarization. The developmental alterations in potassium channel functioning were generally consistent with their mRNA and protein expression levels in arterial smooth muscle. CONCLUSION The negative feedback regulation of vasocontraction by potassium channels varies during maturation depending on the channel type. A dominating contribution of Kv 7 channels to the regulation of basal tone and agonist-induced contraction was observed in arteries of 10- to 15-day-old animals.
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Affiliation(s)
- Anastasia A. Shvetsova
- Centre for Biomedicine and Medical Technology Mannheim (CBTM); European Center of Angioscience (ECAS); Research Division Cardiovascular Physiology; Medical Faculty Mannheim; Heidelberg University; Heidelberg Germany
- Faculty of Biology; M.V. Lomonosov Moscow State University; Moscow Russia
- State Research Center of the Russian Federation - Institute for Biomedical Problems; Russian Academy of Sciences; Moscow Russia
| | - Dina K. Gaynullina
- Faculty of Biology; M.V. Lomonosov Moscow State University; Moscow Russia
- State Research Center of the Russian Federation - Institute for Biomedical Problems; Russian Academy of Sciences; Moscow Russia
- Department of Physiology; Russian National Research Medical University; Moscow Russia
| | - Olga S. Tarasova
- Faculty of Biology; M.V. Lomonosov Moscow State University; Moscow Russia
- State Research Center of the Russian Federation - Institute for Biomedical Problems; Russian Academy of Sciences; Moscow Russia
| | - Rudolf Schubert
- Centre for Biomedicine and Medical Technology Mannheim (CBTM); European Center of Angioscience (ECAS); Research Division Cardiovascular Physiology; Medical Faculty Mannheim; Heidelberg University; Heidelberg Germany
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Wang L, Qiao GH, Hu HN, Gao ZB, Nan FJ. Discovery of Novel Retigabine Derivatives as Potent KCNQ4 and KCNQ5 Channel Agonists with Improved Specificity. ACS Med Chem Lett 2019; 10:27-33. [PMID: 30655942 DOI: 10.1021/acsmedchemlett.8b00315] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 12/19/2018] [Indexed: 12/22/2022] Open
Abstract
Recent research suggests that KCNQ isoforms, particularly the KCNQ4 and KCNQ5 subtypes expressed in smooth muscle cells, are involved in both establishing and maintaining resting membrane potentials and regulating smooth muscle contractility. Retigabine (RTG) is a first-in-class antiepileptic drug that potentiates neuronal KCNQ potassium channels, but poor subtype selectivity limits its further application as a pharmacological tool. In this study, we improved the subtype specificity of retigabine by altering the N-1/3 substituents and discovered several compounds that show better selectivity for KCNQ4 and KCNQ5 channels. Among these compounds, 10g is highly selective for KCNQ4 and KCNQ5 channels without potentiating KCNQ1 and KCNQ2 channels. These results are an advance in the exploration of small molecule modifiers that selectively activate different KCNQ isoforms. The developed compounds could also serve as new pharmacological tools for elucidating the function of KCNQ channels natively expressed in various tissues.
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Affiliation(s)
- Lei Wang
- State Key Laboratory of Drug Research, The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Guan-Hua Qiao
- State Key Laboratory of Drug Research, The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, P. R. China
| | - Hai-Ning Hu
- State Key Laboratory of Drug Research, The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Zhao-Bing Gao
- State Key Laboratory of Drug Research, The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Fa-Jun Nan
- State Key Laboratory of Drug Research, The National Center for Drug Screening, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
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López-López JR, Cidad P, Pérez-García MT. Kv channels and vascular smooth muscle cell proliferation. Microcirculation 2018; 25. [PMID: 29110368 DOI: 10.1111/micc.12427] [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: 07/26/2017] [Accepted: 10/30/2017] [Indexed: 12/12/2022]
Abstract
Kv channels are present in virtually all VSMCs and strongly influence contractile responses. However, they are also instrumental in the proliferative, migratory, and secretory functions of synthetic, dedifferentiated VSMCs upon PM. In fact, Kv channels not only contribute to all these processes but also are active players in the phenotypic switch itself. This review is focused on the role(s) of Kv channels in VSMC proliferation, which is one of the best characterized functions of dedifferentiated VSMCs. VSMC proliferation is a complex process requiring specific Kv channels at specific time and locations. Their identification is further complicated by their large diversity and the differences in expression across vascular beds. Of interest, both conserved changes in some Kv channels and vascular bed-specific regulation of others seem to coexist and participate in VSMC proliferation through complementary mechanisms. Such a system will add flexibility to the process while providing the required robustness to preserve this fundamental cellular response.
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Affiliation(s)
- José R López-López
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Pilar Cidad
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - M Teresa Pérez-García
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
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38
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Hasan R, Jaggar JH. K V channel trafficking and control of vascular tone. Microcirculation 2018; 25. [PMID: 28963858 DOI: 10.1111/micc.12418] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 09/25/2017] [Indexed: 12/21/2022]
Abstract
Membrane potential is a principal regulator of arterial contractility. Arterial smooth muscle cells express several different types of ion channel that control membrane potential, including KV channels. KV channel activation leads to membrane hyperpolarization, resulting in inhibition of voltage-dependent Ca2+ channels, a reduction in [Ca2+ ]i , and vasodilation. In contrast, KV channel inhibition leads to membrane depolarization and vasoconstriction. The ability of KV channels to regulate arterial contractility is dependent upon the number of plasma membrane-resident channels and their open probability. Here, we will discuss mechanisms that alter the surface abundance of KV channel proteins in arterial smooth muscle cells and the functional consequences of such regulation. Cellular processes that will be described include those that modulate KV channel transcription, retrograde and anterograde trafficking, and protein degradation.
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Affiliation(s)
- Raquibul Hasan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Jonathan H Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, USA
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Gollasch M, Welsh DG, Schubert R. Perivascular adipose tissue and the dynamic regulation of K v 7 and K ir channels: Implications for resistant hypertension. Microcirculation 2018; 25. [PMID: 29211322 DOI: 10.1111/micc.12434] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 11/30/2017] [Indexed: 12/20/2022]
Abstract
Resistant hypertension is defined as high blood pressure that remains uncontrolled despite treatment with at least three antihypertensive drugs at adequate doses. Resistant hypertension is an increasingly common clinical problem in older age, obesity, diabetes, sleep apnea, and chronic kidney disease. Although the direct vasodilator minoxidil was introduced in the early 1970s, only recently has this drug been shown to be particularly effective in a subgroup of patients with treatment-resistant or uncontrolled hypertension. This pharmacological approach is interesting from a mechanistic perspective as minoxidil is the only clinically used K+ channel opener today, which targets a subclass of K+ channels, namely KATP channels in VSMCs. Beside KATP channels, two other classes of VSMC K+ channels could represent novel effective targets for treatment of resistant hypertension, namely Kv 7 (KCNQ) and inward rectifier potassium (Kir 2.1) channels. Interestingly, these channels are unique among VSMC potassium channels. First, both have been implicated in the control of microvascular tone by perivascular adipose tissue. Second, they exhibit biophysical properties strongly controlled and regulated by membrane voltage, but not intracellular calcium. This review focuses on Kv 7 (Kv 7.1-5) and Kir (Kir 2.1) channels in VSMCs as potential novel drug targets for treatment of resistant hypertension, particularly in comorbid conditions such as obesity and metabolic syndrome.
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Affiliation(s)
- Maik Gollasch
- Medical Clinic for Nephrology and Internal Intensive Care, Charité Campus Virchow Klinikum, Experimental and Clinical Research Center (ECRC) - a joint cooperation between the Charité - University Medicine Berlin and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Donald G Welsh
- Department of Physiology and Pharmacology, Western University, London, ON, Canada
| | - Rudolf Schubert
- Centre for Biomedicine and Medical Technology Mannheim (CBTM), Research Division Cardiovascular Physiology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
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Namgoong H, Cho C, Lee S. The Kv7 channel activator, retigabine, induces vasorelaxation via an endothelial-independent pathway in male mouse aorta. J Exerc Nutrition Biochem 2018; 22:51-55. [PMID: 30343562 PMCID: PMC6199484 DOI: 10.20463/jenb.2018.0024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 09/27/2018] [Indexed: 11/22/2022] Open
Abstract
PURPOSE Previous studies have indicated that Kv7 channels have an important role in the regulation of blood vessel reactivity, including in the coronary, renal, and cerebral arteries. The present studies examined whether Kv7 channels regulated vascular reactivity in the mouse aorta and investigated the mechanisms involved in the reactivity. METHODS Wild-type (WT) male C57BL/6 mice, between 10 and 15 weeks old, were used in this study. The vascular function of the aorta in WT male mice was assessed by using a pin myography system (Model 620; DMT, Denmark). RESULTS Vasorelaxation by an endothelial-dependent vasodilator, acetylcholine (ACh, 1 nM - 10 μM) and an endothelial-independent vasodilator, sodium nitroprusside (SNP, 1 nM - 10 μM) was induced in the aorta in a dose-dependent manner. Pre-incubation with the nitric oxide synthase inhibitor, L-NAME (100 μM, 20 min), completely abolished ACh-induced vasorelaxation, but did not block retigabine-induced vasorelaxation, which suggested that retigabine caused vasorelaxation in the aorta via smooth muscle activation rather than via endothelial cells. Pre-application of the Kv7 channel blocker, linopirdine (10 μM), resulted in a greater contractile response compared with that induced by vehicle in the aorta. In addition, pre-incubation with linopirdine (10 μM, 20 min) reduced retigabine-induced vasorelaxation (1-50 μM). CONCLUSION This study has provided evidence that Kv7 channels may play a role in the regulation of aortic blood flow via smooth muscle activation.
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Wang N, Kuczmanski A, Dubrovska G, Gollasch M. Palmitic Acid Methyl Ester and Its Relation to Control of Tone of Human Visceral Arteries and Rat Aortas by Perivascular Adipose Tissue. Front Physiol 2018; 9:583. [PMID: 29875688 PMCID: PMC5974537 DOI: 10.3389/fphys.2018.00583] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 05/01/2018] [Indexed: 01/01/2023] Open
Abstract
Background: Perivascular adipose tissue (PVAT) exerts anti-contractile effects on visceral arteries by release of various perivascular relaxing factors (PVRFs) and opening voltage-gated K+ (Kv) channels in vascular smooth muscle cells (VSMCs). Palmitic acid methyl ester (PAME) has been proposed as transferable PVRF in rat aorta. Here, we studied PVAT regulation of arterial tone of human mesenteric arteries and clarified the contribution of Kv channels and PAME in the effects. Methods: Wire myography was used to measure vasocontractions of mesenteric artery rings from patients undergoing abdominal surgery. Isolated aortic rings from Sprague-Dawley rats were studied for comparison. PVAT was either left intact or removed from the arterial rings. Vasocontractions were induced by external high K+ (60 mM), serotonin (5-HT) or phenylephrine. PAME (10 nM−3 μM) was used as vasodilator. Kv channels were blocked by XE991, a Kv7 (KCNQ) channel inhibitor, or by 4-aminopyridine, a non-specific Kv channel inhibitor. PAME was measured in bathing solutions incubated with rat peri-aortic or human visceral adipose tissue. Results: We found that PVAT displayed anti-contractile effects in both human mesenteric arteries and rat aortas. The anti-contractile effects were inhibited by XE991 (30 μM). PAME (EC50 ~1.4 μM) was capable to produce relaxations of PVAT-removed rat aortas. These effects were abolished by XE991 (30 μM), but not 4-aminopyridine (2 mM) or NDGA (10 μM), a lipoxygenases inhibitor. The cytochrome P450 epoxygenase inhibitor 17-octadecynoic acid (ODYA 10 μM) and the soluble epoxide hydrolase inhibitor 12-(3-adamantan-1-ylureido)-dodecanoic acid (AUDA 10 μM) slightly decreased PAME relaxations. PAME up to 10 μM failed to induce relaxations of PVAT-removed human mesenteric arteries. 5-HT induced endogenous PAME release from rat peri-aortic adipose tissue, but not from human visceral adipose tissue. Conclusions: Our data also suggest that Kv7 channels are involved in the anti-contractile effects of PVAT on arterial tone in both rat aorta and human mesenteric arteries. PAME could contribute to PVAT relaxations by activating Kv7 channels in rat aorta, but not in human mesenteric arteries.
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Affiliation(s)
- Ning Wang
- Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Artur Kuczmanski
- Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,HELIOS Klinikum Berlin-Buch, Berlin, Germany
| | - Galyna Dubrovska
- Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Maik Gollasch
- Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,Medical Clinic of Nephrology and Internal Intensive Care, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Barrese V, Stott JB, Figueiredo HB, Aubdool AA, Hobbs AJ, Jepps TA, McNeish AJ, Greenwood IA. Angiotensin II Promotes K V7.4 Channels Degradation Through Reduced Interaction With HSP90 (Heat Shock Protein 90). Hypertension 2018; 71:1091-1100. [PMID: 29686000 DOI: 10.1161/hypertensionaha.118.11116] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 03/16/2018] [Accepted: 03/22/2018] [Indexed: 12/11/2022]
Abstract
Voltage-gated Kv7.4 channels have been implicated in vascular smooth muscle cells' activity because they modulate basal arterial contractility, mediate responses to endogenous vasorelaxants, and are downregulated in several arterial beds in different models of hypertension. Angiotensin II (Ang II) is a key player in hypertension that affects the expression of several classes of ion channels. In this study, we evaluated the effects of Ang II on the expression and function of vascular Kv7.4. Western blot and quantitative polymerase chain reaction revealed that in whole rat mesenteric artery, Ang II incubation for 1 to 7 hours decreased Kv7.4 protein expression without reducing transcript levels. Moreover, Ang II decreased XE991 (Kv7)-sensitive currents and attenuated membrane potential hyperpolarization and relaxation induced by the Kv7 activator ML213. Ang II also reduced Kv7.4 staining at the plasma membrane of vascular smooth muscle cells. Proteasome inhibition with MG132 prevented Ang II-induced decrease of Kv7.4 levels and counteracted the functional impairment of ML213-induced relaxation in myography experiments. Proximity ligation assays showed that Ang II impaired the interaction of Kv7.4 with the molecular chaperone HSP90 (heat shock protein 90), enhanced the interaction of Kv7.4 with the E3 ubiquitin ligase CHIP (C terminus of Hsp70-interacting protein), and increased Kv7.4 ubiquitination. Similar alterations were found in mesenteric vascular smooth muscle cells isolated from Ang II-infused mice. The effect of Ang II was emulated by 17-AAG (17-demethoxy-17-(2-propenylamino) geldanamycin) that inhibits HSP90 interactions with client proteins. These results show that Ang II downregulates Kv7.4 by altering protein stability through a decrease of its interaction with HSP90. This leads to the recruitment of CHIP and Kv7.4 ubiquitination and degradation via the proteasome.
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Affiliation(s)
- Vincenzo Barrese
- From the Vascular Research Centre, Institute of Molecular and Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., H.B.F., I.A.G.)
| | - Jennifer B Stott
- From the Vascular Research Centre, Institute of Molecular and Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., H.B.F., I.A.G.)
| | - Hericka B Figueiredo
- From the Vascular Research Centre, Institute of Molecular and Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., H.B.F., I.A.G.)
| | - Aisah A Aubdool
- William Harvey Research Institute, Barts and The London School of Medicine, Queen Mary, University of London, United Kingdom (A.A.A., A.J.H.)
| | - Adrian J Hobbs
- William Harvey Research Institute, Barts and The London School of Medicine, Queen Mary, University of London, United Kingdom (A.A.A., A.J.H.)
| | - Thomas A Jepps
- Department of Biomedical Sciences, University of Copenhagen, Denmark (T.A.J.)
| | - Alister J McNeish
- and Reading School of Pharmacy, University of Reading, United Kingdom (A.J.M.)
| | - Iain A Greenwood
- From the Vascular Research Centre, Institute of Molecular and Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., H.B.F., I.A.G.)
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Berg T. Kv7(KCNQ)-K +-Channels Influence Total Peripheral Resistance in Female but Not Male Rats, and Hamper Catecholamine Release in Hypertensive Rats of Both Sexes. Front Physiol 2018. [PMID: 29515459 PMCID: PMC5826282 DOI: 10.3389/fphys.2018.00117] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
K+-channels of the Kv7/KCNQ-family hyperpolarize and stabilize excitable cells such as autonomic neurons and vascular smooth muscle cells (VSMC). Kv7 may therefore play a role in blood pressure (BP) homeostasis, and prevent a high total peripheral vascular resistance (TPR), a hallmark of hypertensive disease. The present study analyzed if Kv7 channels influence catecholamine release and TPR in normotensive (WKY) and spontaneously hypertensive rats (SHR), and if they may contribute to the antihypertensive protection seen in young, female SHR. Tyramine-stimulated norepinephrine release evokes an adrenergic cardiovascular response, and also allows modulation of release to be reflected in the overflow to plasma. The experiment itself activated some secretion of epinephrine. The results show: (1) XE-991 (Kv7.1-7.4-inhibitor), but not chromanol 293B (Kv7.1-inhibitor), increased tyramine-stimulated norepinephrine overflow and epinephrine secretion in both sexes in SHR, but not WKY. (2) Surprisingly, the Kv7-openers retigabine (Kv7.2-7.5) and ICA-27243 (Kv7.2-7.3-preferring) increased catecholamine release in female SHR. (3) The rise in TPR following tyramine-stimulated norepinephrine release was increased by XE-991 but not chromanol in the female WKY only. (4) Retigabine and ICA-27243 reduced the TPR-response to tyramine in the female SHR only. These results suggested: (1) Up-regulation of Kv7.2-7.3 function in sympathetic neurons and chromaffin cells hampered catecholamine release in SHR of both sexes. (2) The increase catecholamine release observed after channel openers in the female SHR may possibly involve reduced transmission in cholinergic neurons which hamper catecholamine release. These two mechanisms may serve to counter-act the hyperadrenergic state in SHR. (3) Kv7.4, most likely in the vasculature, opposed the tension-response to norepinephrine in the female WKY. (4) Vascular Kv7.4-7.5 could be stimulated and then opposed norepinephrine-induced vasoconstriction in the female SHR. (5) Vascular Kv7 channels did not counter-act norepinephrine induced vasoconstriction in male rats, possibly due to different Kv7 channel regulation. Kv7 channels may represent a novel target for antihypertensive therapy.
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Affiliation(s)
- Torill Berg
- Division of Physiology, Department of Molecular Medicine, Institute for Basic Medical Sciences, University of Oslo, Oslo, Norway
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44
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Barrese V, Stott JB, Greenwood IA. KCNQ-Encoded Potassium Channels as Therapeutic Targets. Annu Rev Pharmacol Toxicol 2018; 58:625-648. [DOI: 10.1146/annurev-pharmtox-010617-052912] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - Iain A. Greenwood
- Vascular Biology Research Centre, Molecular and Clinical Sciences Institute, St George's, University of London, London, SW17 0RE, United Kingdom;, ,
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45
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Khammy MM, Kim S, Bentzen BH, Lee S, Choi I, Aalkjaer C, Jepps TA. 4-Aminopyridine: a pan voltage-gated potassium channel inhibitor that enhances K v 7.4 currents and inhibits noradrenaline-mediated contraction of rat mesenteric small arteries. Br J Pharmacol 2018; 175:501-516. [PMID: 29156097 DOI: 10.1111/bph.14097] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 11/01/2017] [Accepted: 11/08/2017] [Indexed: 01/14/2023] Open
Abstract
BACKGROUND AND PURPOSE Kv 7.4 and Kv 7.5 channels are regulators of vascular tone. 4-Aminopyridine (4-AP) is considered a broad inhibitor of voltage-gated potassium (KV ) channels, with little inhibitory effect on Kv 7 family members at mmol concentrations. However, the effect of 4-AP on Kv 7 channels has not been systematically studied. The aim of this study was to investigate the pharmacological activity of 4-AP on Kv 7.4 and Kv 7.5 channels and characterize the effect of 4-AP on rat resistance arteries. EXPERIMENTAL APPROACH Voltage clamp experiments were performed on Xenopus laevis oocytes injected with cRNA encoding KCNQ4 or KCNQ5, HEK cells expressing Kv 7.4 channels and on rat, freshly isolated mesenteric artery smooth muscle cells. The effect of 4-AP on tension, membrane potential, intracellular calcium and pH was assessed in rat mesenteric artery segments. KEY RESULTS 4-AP increased the Kv 7.4-mediated current in oocytes and HEK cells but did not affect Kv 7.5 current. 4-AP also enhanced native mesenteric artery myocyte K+ current at sub-mmol concentrations. When applied to NA-preconstricted mesenteric artery segments, 4-AP hyperpolarized the membrane, decreased [Ca2+ ]i and caused concentration-dependent relaxations that were independent of 4-AP-mediated changes in intracellular pH. Application of the Kv 7 channel blocker XE991 and BKCa channel blocker iberiotoxin attenuated 4-AP-mediated relaxation. 4-AP also inhibited the NA-mediated signal transduction to elicit a relaxation. CONCLUSIONS AND IMPLICATIONS These data show that 4-AP is able to relax NA-preconstricted rat mesenteric arteries by enhancing the activity of Kv 7.4 and BKCa channels and attenuating NA-mediated signalling.
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Affiliation(s)
- Makhala M Khammy
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Sukhan Kim
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Bo H Bentzen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Soojung Lee
- Department of Physiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Inyeong Choi
- Department of Physiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Christian Aalkjaer
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Thomas A Jepps
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Nieves-Cintrón M, Syed AU, Nystoriak MA, Navedo MF. Regulation of voltage-gated potassium channels in vascular smooth muscle during hypertension and metabolic disorders. Microcirculation 2018; 25:10.1111/micc.12423. [PMID: 29044853 PMCID: PMC5760350 DOI: 10.1111/micc.12423] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/11/2017] [Indexed: 12/12/2022]
Abstract
Voltage-gated potassium (KV ) channels are key regulators of vascular smooth muscle contractility and vascular tone, and thus have major influence on the microcirculation. KV channels are important determinants of vascular smooth muscle membrane potential (Em ). A number of KV subunits are expressed in the plasma membrane of smooth muscle cells. Each subunit confers distinct kinetics and regulatory properties that allow for fine control of Em to orchestrate vascular tone. Modifications in KV subunit expression and/or channel activity can contribute to changes in vascular smooth muscle contractility in response to different stimuli and in diverse pathological conditions. Consistent with this, a number of studies suggest alterations in KV subunit expression and/or function as underlying contributing mechanisms for small resistance artery dysfunction in pathologies such as hypertension and metabolic disorders, including diabetes. Here, we review our current knowledge on the effects of these pathologies on KV channel expression and function in vascular smooth muscle cells, and the repercussions on (micro)vascular function.
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Affiliation(s)
| | - Arsalan U. Syed
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Matthew A. Nystoriak
- Diabetes and Obesity Center, Department of Medicine, University of Louisville, Louisville, KY 40202
| | - Manuel F. Navedo
- Department of Pharmacology, University of California, Davis, CA 95616
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47
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Barrese V, Cidad P, Yeung SY, López-López JR, McNeish AJ, Ohya S, Pérez-García MT, Greenwood IA. Proliferative Role of Kv11 Channels in Murine Arteries. Front Physiol 2017; 8:500. [PMID: 28747891 PMCID: PMC5506201 DOI: 10.3389/fphys.2017.00500] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 06/29/2017] [Indexed: 12/22/2022] Open
Abstract
K+ channels encoded by the ether-a-go-go related gene (ERG1 or KCNH2) are important determinants of the cardiac action potential. Expression of both cardiac isoforms (ERG1a and ERG1b) were identified in murine portal vein and distinctive voltage-gated K+ currents were recorded from single myocytes. The aim of the present study was to ascertain the expression and functional impact of ERG channels in murine arteries. Methods: Quantitative RT-PCR was undertaken on RNA extracted from a number of murine arteries. Immunofluorescence was performed on single vascular smooth muscle cells using antibodies against the ERG1 expression product (Kv11.1). Single cell electrophysiology was performed on myocytes from portal vein and several different arteries, complimented by isometric tension recordings. Proliferation assays were undertaken on smooth muscle cells isolated from femoral arteries. Results: ERG1 transcripts were detected in all murine blood vessels, and Kv11.1 immunofluorescence was observed in all smooth muscle cells. However, K+ currents with properties consistent with ERG channels were only recorded in portal vein myocytes. Moreover, ERG channel blockers (E4031 or dofetilide, 1 μM) failed to depolarize carotid arteries or produce contraction. Proliferation of arterial smooth muscle cells was associated with a marked increase in ERG1 expression and ERG blockers suppressed proliferation significantly. Conclusions: These data reveal that arterial blood vessels express ERG channels that appear to be functional silent in contractile smooth muscle but contribute to proliferative response.
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Affiliation(s)
- Vincenzo Barrese
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's University of LondonLondon, United Kingdom
| | - Pilar Cidad
- Departmento de Fisiología, Universidad de ValladolidValladolid, Spain
| | - Shuk Y Yeung
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's University of LondonLondon, United Kingdom
| | | | - Alister J McNeish
- Reading School of Pharmacy, University of ReadingReading, United Kingdom
| | - Susumu Ohya
- Department of Pharmacology, Kyoto Pharmaceutical UniversityKyoto, Japan
| | | | - Iain A Greenwood
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's University of LondonLondon, United Kingdom
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Zimmer J, Takahashi T, Hofmann AD, Puri P. Downregulation of KCNQ5 expression in the rat pulmonary vasculature of nitrofen-induced congenital diaphragmatic hernia. J Pediatr Surg 2017; 52:702-705. [PMID: 28189443 DOI: 10.1016/j.jpedsurg.2017.01.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 01/23/2017] [Indexed: 12/17/2022]
Abstract
PURPOSE Pulmonary hypertension (PH) is a common complication of congenital diaphragmatic hernia (CDH). Voltage-gated potassium channels KCNQ1, KCNQ4, and KCNQ5 are expressed by rodent pulmonary artery smooth muscle cells, contributing to their vascular tone. We hypothesized that KCNQ1, KCNQ4, and KCNQ5 expression is altered in the pulmonary vasculature of nitrofen-induced CDH rats. METHODS After ethical approval (REC913b), time-pregnant rats received nitrofen or vehicle on gestational day (D)9. D21 fetuses were divided into CDH and control group (n=22). QRT-PCR and western blotting were performed to determine gene and protein expression of KCNQ1, KCNQ4, and KCNQ5. Confocal microscopy was used to detect these proteins in the pulmonary vasculature. RESULTS Relative mRNA level of KCNQ5 (p=0.025) was significantly downregulated in CDH lungs compared to controls. KCNQ1 (p=0.052) and KCNQ4 (p=0.574) expression was not altered. Western blotting confirmed the decreased pulmonary KCNQ5 protein expression in CDH lungs. Confocal-microscopy detected a markedly diminished KCNQ5 expression in pulmonary vasculature of CDH fetuses. CONCLUSIONS Downregulated pulmonary expression of KCNQ5 in CDH lungs suggests that this potassium channel may play an important role in the development of PH in this model. KCNQ5 channel activator drugs may be a potential therapeutic target for the treatment of PH in CDH. LEVEL OF EVIDENCE 2b (Centre for Evidence-Based Medicine, Oxford).
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Affiliation(s)
- Julia Zimmer
- National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Gate 5, Dublin 12, Dublin, Ireland
| | - Toshiaki Takahashi
- National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Gate 5, Dublin 12, Dublin, Ireland
| | - Alejandro D Hofmann
- Department of Pediatric Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany
| | - Prem Puri
- National Children's Research Centre, Our Lady's Children's Hospital Crumlin, Gate 5, Dublin 12, Dublin, Ireland; School of Medicine and Medical Science and Conway Institute of Biomedical Research, University College Dublin, Belfield, Dublin 4, Dublin, Ireland.
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Huang KC, Li TM, Liu X, Chen JH, Chien WK, Shiao YT, Tsang H, Lin TH, Liao CC, Huang SM, Li JP, Lin CW, Lin JC, Lin CC, Lai CH, Cheng CF, Liang WM, Hung CH, Chen CC, Lin YJ, Tsai FJ. KCNQ1 variants associate with hypertension in type 2 diabetes and affect smooth muscle contractility in vitro. J Cell Physiol 2017; 232:3309-3316. [PMID: 28059450 DOI: 10.1002/jcp.25775] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 12/19/2022]
Abstract
KCNQ1 encodes a potassium voltage-gated channel and represents a susceptibility locus for type 2 diabetes mellitus (T2DM). Here, we explored the association between KCNQ1 polymorphisms and hypertension risk in individuals with T2DM, as well as the role of KCNQ1 in vascular smooth muscle cell contraction in vitro. To investigate the relationship between KCNQ1 and the risk of developing hypertension in patients with T2DM, we divided the T2DM cohort into hypertension (n = 452) and non-hypertension (n = 541) groups. The Mann-Whitney U test, chi-square test, and multivariate regression analyses were used to assess the clinical characteristics and genotypic frequencies. In vitro studies utilized the rat aortic smooth muscle A10 cell line. Patients in the hypertension group were significantly older at the time of enrollment and had higher levels of body mass index, waist-to-hip ratio, and triglyceride than those in the non-hypertension group. The KCNQ1 rs3864884 and rs12576239 genetic variants were associated with hypertension in T2DM. KCNQ1 expression was lower in the individuals with the CC versus the CT and TT genotypes. Smooth muscle cell contractility was inhibited by treatment with a KCNQ1 inhibitor. These results suggest that KCNQ1 might be associated with hypertension in individuals with T2DM.
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Affiliation(s)
- Kuo-Chin Huang
- School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Department of Integration of Traditional Chinese and Western Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Te-Mao Li
- School of Chinese Medicine, China Medical University, Taichung, Taiwan
| | - Xiang Liu
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Jin-Hua Chen
- Biostatistics Center and School of Public Health, China Medical University, Taichung, Taiwan.,Biostatistics Center and School of Public Health, Taipei Medical University, Taipei, Taiwan
| | - Wen-Kuei Chien
- National Applied Research Laboratories, National Center for High-Performance Computing, Hsinchu, Taiwan
| | - Yi-Tzone Shiao
- Heart Center, China Medical University Hospital, Taichung, Taiwan
| | - Hsinyi Tsang
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
| | - Ting-Hsu Lin
- Genetic Center, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Chiu-Chu Liao
- Genetic Center, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Shao-Mei Huang
- Genetic Center, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Ju-Pi Li
- School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Rheumatism Research Center, China Medical University Hospital, Taichung, Taiwan
| | - Cheng-Wen Lin
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan
| | - Jung-Chun Lin
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan
| | - Chih-Chien Lin
- Department of Cosmetic Science, Providence University, Taichung, Taiwan
| | - Chih-Ho Lai
- Department of Microbiology and Immunology, Chang Gung University, Taoyuan, Taiwan
| | - Chi-Fung Cheng
- Graduate Institute of Biostatistics, School of Public Health, China Medical University, Taichung, Taiwan
| | - Wen-Miin Liang
- Graduate Institute of Biostatistics, School of Public Health, China Medical University, Taichung, Taiwan
| | - Chien-Hui Hung
- Graduate Institute of Clinical Medical Science, Chang-Gung University, Taipei, Taiwan
| | - Ching-Chu Chen
- School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Division of Endocrinology and Metabolism, Department of Medicine, China Medical University Hospital, Taichung, Taiwan
| | - Ying-Ju Lin
- School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Genetic Center, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Fuu-Jen Tsai
- School of Chinese Medicine, China Medical University, Taichung, Taiwan.,Genetic Center, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.,Asia University, Taichung, Taiwan
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Unravelling the complexities of vascular smooth muscle ion channels: Fine tuning of activity by ancillary subunits. Pharmacol Ther 2017; 178:57-66. [PMID: 28336473 DOI: 10.1016/j.pharmthera.2017.03.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Which ion channel is the most important for regulating vascular tone? Which one is responsible for controlling the resting membrane potential or repolarization? Which channels are recruited by different intracellular signalling pathways or change in certain vascular diseases? Many different ion channels have been identified in the vasculature over the years and claimed as future therapeutic targets. Unfortunately, several of these ion channels are not just found in the vasculature, with many of them also found to have prominent functional roles in different organs of the body, which then leads to off-target effects. As cardiovascular diseases are expected to increase worldwide to epidemic proportions, ion channel research and the hunt for the next major therapeutic target to treat different vascular diseases has never been more important. However, I believe that the question we should now be asking is: which ancillary subunits are involved in regulating specific ion channels in the vasculature and do they have the potential to be new therapeutic targets?
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