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Heo R, Park M, Mun SY, Zhuang W, Jeong J, Park H, Han ET, Han JH, Chun W, Jung WK, Choi IW, Park WS. Vasorelaxant mechanisms of the antidiabetic anagliptin in rabbit aorta: roles of Kv channels and SERCA pump. Acta Diabetol 2024:10.1007/s00592-024-02351-9. [PMID: 39103505 DOI: 10.1007/s00592-024-02351-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 07/29/2024] [Indexed: 08/07/2024]
Abstract
AIMS The present study investigated the vasorelaxant mechanisms of an oral antidiabetic drug, anagliptin, using phenylephrine (Phe)-induced pre-contracted rabbit aortic rings. METHODS Arterial tone measurement was performed in rabbit thoracic aortic rings. RESULTS Anagliptin induced vasorelaxation in a dose-dependent manner. Pre-treatment with the classical voltagedependent K+ (Kv) channel inhibitors 4-aminopyridine and tetraethylammonium significantly decreased the vasorelaxant effect of anagliptin, whereas pre-treatment with the inwardly rectifying K+ (Kir) channel inhibitor Ba2+, the ATP-sensitive K+ (KATP) channel inhibitor glibenclamide, and the large-conductance Ca2+-activated K+ (BKCa) channel inhibitor paxilline did not attenuate the vasorelaxant effect. Furthermore, the vasorelaxant response of anagliptin was effectively inhibited by pre-treatment with the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) pump inhibitors thapsigargin and cyclopiazonic acid. Neither cAMP/protein kinase A (PKA)-related signaling pathway inhibitors (adenylyl cyclase inhibitor SQ 22536 and PKA inhibitor KT 5720) nor cGMP/protein kinase G (PKG)-related signaling pathway inhibitors (guanylyl cyclase inhibitor ODQ and PKG inhibitor KT 5823) reduced the vasorelaxant effect of anagliptin. Similarly, the anagliptin-induced vasorelaxation was independent of the endothelium. CONCLUSIONS Based on these results, we suggest that anagliptin-induced vasorelaxation in rabbit aortic smooth muscle occurs by activating Kv channels and the SERCA pump, independent of other vascular K+ channels, cAMP/PKA- or cGMP/PKG-related signaling pathways, and the endothelium.
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Affiliation(s)
- Ryeon Heo
- Department of Physiology, Seoul National University College of Medicine, Seoul, 03080, South Korea
| | - Minju Park
- Department of Physiology, Institute of Medical Sciences, Kangwon National University School of Medicine, 1 Kangwondaehak-Gil, Chuncheon, 24341, South Korea
| | - Seo-Yeong Mun
- Department of Physiology, Institute of Medical Sciences, Kangwon National University School of Medicine, 1 Kangwondaehak-Gil, Chuncheon, 24341, South Korea
| | - Wenwen Zhuang
- Department of Physiology, Institute of Medical Sciences, Kangwon National University School of Medicine, 1 Kangwondaehak-Gil, Chuncheon, 24341, South Korea
| | - Junsu Jeong
- Department of Physiology, Institute of Medical Sciences, Kangwon National University School of Medicine, 1 Kangwondaehak-Gil, Chuncheon, 24341, South Korea
| | - Hongzoo Park
- Department of Urology, Institute of Medical Sciences, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Eun-Taek Han
- Department of Medical Environmental Biology and Tropical Medicine, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Wanjoo Chun
- Department of Pharmacology, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Won-Kyo Jung
- Department of Biomedical Engineering, and Center for Marine-Integrated Biomedical Technology (BK21 Plus), Pukyong National University, Busan, 48513, South Korea
| | - Il-Whan Choi
- Department of Microbiology, College of Medicine, Inje University, Busan, 48516, South Korea
| | - Won Sun Park
- Department of Physiology, Institute of Medical Sciences, Kangwon National University School of Medicine, 1 Kangwondaehak-Gil, Chuncheon, 24341, South Korea.
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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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van der Horst J, Jepps TA. Proximity Labelling to Quantify Kv7.4 and Dynein Protein Interaction in Freshly Isolated Rat Vascular Smooth Muscle Cells. Bio Protoc 2024; 14:e4961. [PMID: 38841287 PMCID: PMC10958171 DOI: 10.21769/bioprotoc.4961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Revised: 02/07/2024] [Accepted: 02/07/2024] [Indexed: 06/07/2024] Open
Abstract
Understanding protein-protein interactions is crucial for unravelling subcellular protein distribution, contributing to our understanding of cellular organisation. Moreover, interaction studies can reveal insights into the mechanisms that cover protein trafficking within cells. Although various techniques such as Förster resonance energy transfer (FRET), co-immunoprecipitation, and fluorescence microscopy are commonly employed to detect protein interactions, their limitations have led to more advanced techniques such as the in situ proximity ligation assay (PLA) for spatial co-localisation analysis. The PLA technique, specifically employed in fixed cells and tissues, utilises species-specific secondary PLA probes linked to DNA oligonucleotides. When proteins are within 40 nm of each other, the DNA oligonucleotides on the probes interact, facilitating circular DNA formation through ligation. Rolling-circle amplification then produces DNA circles linked to the PLA probe. Fluorescently labelled oligonucleotides hybridise to the circles, generating detectable signals for precise co-localisation analysis. We employed PLA to examine the co-localisation of dynein with the Kv7.4 channel protein in isolated vascular smooth muscle cells from rat mesenteric arteries. This method enabled us to investigate whether Kv7.4 channels interact with dynein, thereby providing evidence of their retrograde transport by the microtubule network. Our findings illustrate that PLA is a valuable tool for studying potential novel protein interactions with dynein, and the quantifiable approach offers insights into whether these interactions are changed in disease.
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Affiliation(s)
- Jennifer van der Horst
- 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
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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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Zhuang W, Mun SY, Park M, Jeong J, Park H, Na S, Lee SJ, Jung WK, Choi IW, Li H, Park WS. Lurasidone blocks the voltage-gated potassium channels of coronary arterial smooth muscle cells. Eur J Pharmacol 2023; 957:176005. [PMID: 37611842 DOI: 10.1016/j.ejphar.2023.176005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 08/10/2023] [Accepted: 08/18/2023] [Indexed: 08/25/2023]
Abstract
Lurasidone is a second-generation antipsychotic drug used to treat schizophrenia, mania, and bipolar disorder. The drug is an antagonist of the 5-HT2A and D2 receptors. No effect of lurasidone on the voltage-gated K+ (Kv) channels has yet been identified. Here, we show that lurasidone inhibits the vascular Kv channels of rabbit coronary arterial smooth muscle cells in a dose-dependent manner with an IC50 of 1.88 ± 0.21 μM and a Hill coefficient of 0.98 ± 0.09. Although lurasidone (3 μM) did not affect the activation kinetics, the drug negatively shifted the inactivation curve, suggesting that the drug interacted with the voltage sensors of Kv channels. Application of 1 or 2 Hz train steps in the presence of lurasidone significantly increased Kv current inhibition. The recovery time after channel inactivation increased in the presence of lurasidone. These results suggest that the inhibitory action of lurasidone is use (state)-dependent. Pretreatment with a Kv 1.5 subtype inhibitor effectively reduced the inhibitory effect of lurasidone. However, the inhibitory effect on Kv channels did not markedly change after pretreatment with a Kv 2.1 or a Kv7 subtype inhibitor. In summary, lurasidone inhibits vascular Kv channels (primarily the Kv1.5 subtype) in a concentration- and use (state)-dependent manner by shifting the steady-state inactivation curve.
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Affiliation(s)
- Wenwen Zhuang
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Seo-Yeong Mun
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Minju Park
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Junsu Jeong
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Hongzoo Park
- Institute of Medical Sciences, Department of Urology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea
| | - Sunghun Na
- Institute of Medical Sciences, Department of Obstetrics and Gynecology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, 24341, 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, 24341, South Korea
| | - Won-Kyo Jung
- Department of Biomedical Engineering, Center for Marine-Integrated Biomedical Technology (BK21 Plus), Pukyong National University, Busan, 48513, South Korea
| | - Il-Whan Choi
- Department of Microbiology, College of Medicine, Inje University, Busan, 48516, South Korea
| | - Hongliang Li
- Institute of Translational Medicine, Medical College, Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment for Senile Diseases, Yangzhou University, Yangzhou, 225001, Jiangsu, China
| | - Won Sun Park
- Institute of Medical Sciences, Department of Physiology, Kangwon National University School of Medicine, Chuncheon, 24341, South Korea.
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Villegas-Esguevillas M, Cho S, Vera-Zambrano A, Kwon JW, Barreira B, Telli G, Navarro-Dorado J, Morales-Cano D, de Olaiz B, Moreno L, Greenwood I, Pérez-Vizcaíno F, Kim SJ, Climent B, Cogolludo A. The novel K V7 channel activator URO-K10 exerts enhanced pulmonary vascular effects independent of the KCNE4 regulatory subunit. Biomed Pharmacother 2023; 164:114952. [PMID: 37295249 DOI: 10.1016/j.biopha.2023.114952] [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: 12/21/2022] [Revised: 05/23/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
KV7 channels exert a pivotal role regulating vascular tone in several vascular beds. In this context, KV7 channel agonists represent an attractive strategy for the treatment of pulmonary arterial hypertension (PAH). Therefore, in this study, we have explored the pulmonary vascular effects of the novel KV7 channel agonist URO-K10. Consequently, the vasodilator and electrophysiological effects of URO-K10 were tested in rat and human pulmonary arteries (PA) and PA smooth muscle cells (PASMC) using myography and patch-clamp techniques. Protein expression was also determined by Western blot. Morpholino-induced knockdown of KCNE4 was assessed in isolated PA. PASMC proliferation was measured by BrdU incorporation assay. In summary, our data show that URO-K10 is a more effective relaxant of PA than the classical KV7 activators retigabine and flupirtine. URO-K10 enhanced KV currents in PASMC and its electrophysiological and relaxant effects were inhibited by the KV7 channel blocker XE991. The effects of URO-K10 were confirmed in human PA. URO-K10 also exhibited antiproliferative effects in human PASMC. Unlike retigabine and flupirtine, URO-K10-induced pulmonary vasodilation was not affected by morpholino-induced knockdown of the KCNE4 regulatory subunit. Noteworthy, the pulmonary vasodilator efficacy of this compound was considerably increased under conditions mimicking the ionic remodelling (as an in vitro model of PAH) and in PA from monocrotaline-induced pulmonary hypertensive rats. Taking all together, URO-K10 behaves as a KCNE4-independent KV7 channel activator with much increased pulmonary vascular effects compared to classical KV7 channel activators. Our study identifies a promising new drug in the context of PAH.
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Affiliation(s)
- Marta Villegas-Esguevillas
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Suhan Cho
- Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
| | - Alba Vera-Zambrano
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Jae Won Kwon
- Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain
| | - Bianca Barreira
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Göcken Telli
- Department of Pharmacology, Faculty of Pharmacy, Hacettepe University, Ankara, Turkey
| | - Jorge Navarro-Dorado
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain
| | - Daniel Morales-Cano
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Beatriz de Olaiz
- Department of Thoracic Surgery, Hospital Universitario de Getafe, Getafe, Spain
| | - Laura Moreno
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Iain Greenwood
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, United Kingdom
| | - Francisco Pérez-Vizcaíno
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
| | - Sung Joon Kim
- Department of Physiology, College of Medicine, Seoul National University, Seoul, South Korea
| | - Belén Climent
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense, Madrid, Spain.
| | - Angel Cogolludo
- Departamento de Farmacología, Facultad de Medicina, Universidad Complutense, Madrid, Spain; Institute of Health Research Gregorio Marañón (IiSGM), Madrid, Spain; CIBER Enfermedades Respiratorias (Ciberes), Madrid, Spain
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Wang Y, Li J, Wang F, Cui Y, Song L, Ruan B, Yu Y. Analysis of ceRNA Regulatory Mechanism of Rape Pollen Allergy Based on Whole-Transcriptome Sequencing of Peripheral Blood Mononuclear Cells. J Asthma Allergy 2023; 16:775-788. [PMID: 37534326 PMCID: PMC10390718 DOI: 10.2147/jaa.s416772] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 07/12/2023] [Indexed: 08/04/2023] Open
Abstract
Background Rape pollen allergy is a common allergic reaction disorder that affects the health and life of patients seriously. The research on ceRNA regulatory network in rape pollen allergy is poor. Methods High throughput whole-transcriptome sequencing was conducted on rape pollen allergic samples and non-allergic samples. Differentially expressed microRNAs (DEmiRNAs), circRNAs (DEcircRNAs), long non-coding RNA (DElncRNAs), mRNA (DEmRNAs) were identified and a ceRNA regulatory network was constructed by Cytoscape. Functional enrichment analyses were performed on DEmRNAs in the ceRNA network. Then, the least absolute shrinkage and selection operator (LASSO) regression model was used to identify characteristic genes for rape pollen allergy. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic ability of characteristic genes. Results A total of 25 DEmiRNAs, 258 DEcircRNAs, 304 DElncRNAs, and 383 DEmRNAs in the allergic group compared with the non-allergic group were uncovered, respectively. A ceRNA network containing 21 miRNAs, 57 circRNAs, 28 lncRNAs, and 33 mRNAs was generated with 139 nodes and 160 edges. The signal transduction-related processes, immune-related processes, the ion, inorganic substance, and hormone regulation processes were associated with mRNAs in the ceRNA network. The results of pathway enrichment illustrated that mRNAs in the ceRNA were significantly linked to IL-17 signaling pathway, inflammatory mediator regulation of trp channels, GMP-PKG signaling pathway, signaling by GPCR, and GPCR downstream signaling pathway. Then, five characteristic genes (KCNQ3, CCR5, FOSB, CFAP43, and PRKG1) were defined by the LASSO algorithm. The AUC values of these genes indicated that these genes had a powerful discrimination ability in discriminating allergic samples from non-allergic samples. Conclusion Taken together, we revealed the ceRNA regulatory network in rape pollen allergy and excavated five characteristic genes (KCNQ3, CCR5, FOSB, CFAP43, and PRKG1) with the diagnostic value that may be a potential target in diagnosis and treatment.
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Affiliation(s)
- Ya Wang
- Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
| | - Jianhua Li
- Department of Otolaryngology, the Sixth Affiliated Hospital of Kunming Medical University, Yuxi, People’s Republic of China
| | - Fang Wang
- Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
| | - Yunhua Cui
- Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
| | - Li Song
- Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
| | - Biao Ruan
- Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
| | - Yongmei Yu
- Department of Otolaryngology, the First Affiliated Hospital of Kunming Medical University, Kunming, People’s Republic of China
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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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Frampton DJA, Choudhury K, Nikesjö J, Delemotte L, Liin SI. Subtype-specific responses of hKv7.4 and hKv7.5 channels to polyunsaturated fatty acids reveal an unconventional modulatory site and mechanism. eLife 2022; 11:77672. [PMID: 35642964 PMCID: PMC9159753 DOI: 10.7554/elife.77672] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
The KV7.4 and KV7.5 subtypes of voltage-gated potassium channels play a role in important physiological processes such as sound amplification in the cochlea and adjusting vascular smooth muscle tone. Therefore, the mechanisms that regulate KV7.4 and KV7.5 channel function are of interest. Here, we study the effect of polyunsaturated fatty acids (PUFAs) on human KV7.4 and KV7.5 channels expressed in Xenopus oocytes. We report that PUFAs facilitate activation of hKV7.5 by shifting the V50 of the conductance versus voltage (G(V)) curve toward more negative voltages. This response depends on the head group charge, as an uncharged PUFA analogue has no effect and a positively charged PUFA analogue induces positive V50 shifts. In contrast, PUFAs inhibit activation of hKV7.4 by shifting V50 toward more positive voltages. No effect on V50 of hKV7.4 is observed by an uncharged or a positively charged PUFA analogue. Thus, the hKV7.5 channel's response to PUFAs is analogous to the one previously observed in hKV7.1-7.3 channels, whereas the hKV7.4 channel response is opposite, revealing subtype-specific responses to PUFAs. We identify a unique inner PUFA interaction site in the voltage-sensing domain of hKV7.4 underlying the PUFA response, revealing an unconventional mechanism of modulation of hKV7.4 by PUFAs.
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Affiliation(s)
- Damon J A Frampton
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Koushik Choudhury
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Solna, Sweden
| | - Johan Nikesjö
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Lucie Delemotte
- Science for Life Laboratory, Department of Applied Physics, KTH Royal Institute of Technology, Solna, Sweden
| | - Sara I Liin
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
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Macêdo CAF, Paiva GOD, Menezes PMN, Ribeiro TF, Brito MC, Vilela DAD, Duarte Filho LAMDS, Ribeiro FPRDA, Lucchese AM, Lima JTD, Silva FS. Lippia origanoides essential oil induces tocolytic effect in virgin rat uterus and inhibits writhing in a dysmenorrhea mouse model. JOURNAL OF ETHNOPHARMACOLOGY 2022; 290:115099. [PMID: 35167934 DOI: 10.1016/j.jep.2022.115099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 01/25/2022] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE The species Lippia origanoides Kunth, popularly known as "salva-de-marajó", is used in Brazilian traditional "quilombola" communities to treat menstrual cramps and uterine inflammation. AIM OF THE STUDY Evaluate the spasmolytic activity of Lippia origanoides essential oil (LOO) on experimental models of uterine conditions related to menstrual cramps and investigate its mechanism of action. MATERIALS AND METHODS Virgin rat-isolated uterus was mounted in the organ bath apparatus to evaluate the spasmolytic effect of LOO on basal tonus and contractions induced by carbachol, KCl, or oxytocin. We used pharmacological agents to verify the relaxation mechanism of LOO. The evaluation of uterine contractility in virgin rats, after treatment with LOO for three consecutive days, was carried out by the construction of a concentration-response curve with oxytocin or carbachol. The primary dysmenorrhea animal model was replicated with an injection of estradiol cypionate in female mice for three consecutive days, followed by intraperitoneal application of oxytocin. RESULTS LOO relaxed the rat uterus precontracted with 10-2 IU/mL oxytocin (logEC50 = 1.98 ± 0.07), 1 μM carbachol (logEC50 = 1.42 ± 0.07) or 60 mM KCl (logEC50 = 1.53 ± 0.05). It was also able relax uterus on spontaneous contractions (logEC50 = 0.41 ± 0.05). Preincubation with glibenclamide, propranolol, phentolamine or L-NAME in contractions induced by carbachol did not alter significantly the relaxing effect of LOO. However, in the presence of 4-aminopyridine, CsCl or tetraethylammonium there was a reduction of LOO potency, whereas the blockers methylene blue, ODQ, aminophylline and heparin potentiated the LOO relaxing effect. Preincubation with LOO in a Ca2+ free medium at concentrations of 27 μg/mL or 81 μg/mL reduced the contraction induced by carbachol. The administration of LOO for 3 days did not alter uterus contractility. The treatment with LOO at 30 or 100 mg/kg intraperitoneally, or 100 mg/kg orally, inhibited writhing in female mice. The association of LOO at 10 mg/kg with nifedipine or mefenamic acid potentiated writhing inhibition in mice. CONCLUSIONS The essential oil of L. origanoides has tocolytic activity in rat isolated uterus pre-contracted with KCl, oxytocin, or carbachol. This effect is possibly related to the opening of potassium channels (Kir, KV, and KCa), cAMP increase, and diminution of intracellular Ca2+. This relaxant effect, probably, contributed to reduce the number of writhings in an animal model of dysmenorrhea being potentiated by nifedipine or mefenamic acid. Taken together, the results here presented indicate that this species has a pharmacological potential for the treatment of primary dysmenorrhea, supporting its use in folk medicine.
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Affiliation(s)
| | - Gabriela Olinda de Paiva
- Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | - Pedro Modesto Nascimento Menezes
- Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil; Rede Nordeste de Biotecnologia, Universidade Federal Rural de Pernambuco (UFRPE), Brazil.
| | - Tiago Feitosa Ribeiro
- Rede Nordeste de Biotecnologia, Universidade Federal Rural de Pernambuco (UFRPE), Brazil.
| | - Mariana Coelho Brito
- Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | | | | | | | - Angélica Maria Lucchese
- Laboratório de Química de Produtos Naturais e Bioativos, Departamento de Ciências Exatas, Universidade Estadual de Feira de Santana (UEFS), Brazil.
| | - Julianeli Tolentino de Lima
- Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | - Fabrício Souza Silva
- Pós-graduação em Biociênicas, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil; Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
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11
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Fan XZ, Wang YY, Cui ZY, Cheng ZH, Zhang HL, Gamper N, Zhang F, Han M. Kv7.4 channel is a key regulator of vascular inflammation and remodeling in neointimal hyperplasia and abdominal aortic aneurysms. Free Radic Biol Med 2022; 178:111-124. [PMID: 34863875 DOI: 10.1016/j.freeradbiomed.2021.11.041] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/08/2021] [Accepted: 11/30/2021] [Indexed: 12/16/2022]
Abstract
Inflammation has recently emerged as an important contributor for cardiovascular disease development and participates pivotally in the development of neointimal hyperplasia and abdominal aortic aneurysms (AAA) formation. Kv7.4/KCNQ4, a K+ channel, is one of the important regulators of vascular function but its role in vascular inflammation is unexplored. Here, we showed that the expression of Kv7.4 channel was elevated in the neointima and AAA tissues from mice and humans. Genetic deletion or pharmacological inhibition of Kv7.4 channel in mice alleviated neointimal hyperplasia and AAA formation via downregulation of a set of vascular inflammation-related genes, matrix metalloproteinases (MMP) 2/9, and intercellular adhesion molecule (ICAM-1). Furthermore, genetic deletion or inhibition of Kv7.4 channel suppressed the activation of tumor necrosis factor receptor 1 (TNFR1)-nuclear factor (NF)-κB signaling pathway via blockade of interaction between TNFR1 and TNFR1-associated death domain protein (TRADD) in vascular smooth muscle cells (VSMCs). Knockdown of Kv7.4 in vivo identified VSMC-expressed Kv7.4 as a major factor in vascular inflammation. Collectively, our findings suggest that Kv7.4 channel aggravates vascular inflammatory response, which promotes the neointimal hyperplasia and AAA formation. Inhibition of Kv7.4 channel may be a novel therapeutic strategy for vascular inflammatory diseases.
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Affiliation(s)
- Xi-Zhenzi Fan
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Key Laboratory of Medical Biotechnology of Hebei Province, Key Laboratory of Neural and Vascular Biology of Ministry of Education, Hebei Medical University, Shijiazhuang, 050017, PR China
| | - Ying-Ying Wang
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Key Laboratory of Medical Biotechnology of Hebei Province, Key Laboratory of Neural and Vascular Biology of Ministry of Education, Hebei Medical University, Shijiazhuang, 050017, PR China
| | - Zi-Yang Cui
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Key Laboratory of Medical Biotechnology of Hebei Province, Key Laboratory of Neural and Vascular Biology of Ministry of Education, Hebei Medical University, Shijiazhuang, 050017, PR China
| | - Zi-Hao Cheng
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Key Laboratory of Medical Biotechnology of Hebei Province, Key Laboratory of Neural and Vascular Biology of Ministry of Education, Hebei Medical University, Shijiazhuang, 050017, PR China
| | - Hai-Lin Zhang
- Department of Pharmacology, Key Laboratory of Neural and Vascular Biology, Ministry of Education, PR China; Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, 050017, PR China
| | - Nikita Gamper
- Department of Pharmacology, Key Laboratory of Neural and Vascular Biology, Ministry of Education, PR China; Key Laboratory of New Drug Pharmacology and Toxicology, Hebei Medical University, Shijiazhuang, 050017, PR China; School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Fan Zhang
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Key Laboratory of Medical Biotechnology of Hebei Province, Key Laboratory of Neural and Vascular Biology of Ministry of Education, Hebei Medical University, Shijiazhuang, 050017, PR China.
| | - Mei Han
- Department of Biochemistry and Molecular Biology, College of Basic Medicine, Key Laboratory of Medical Biotechnology of Hebei Province, Key Laboratory of Neural and Vascular Biology of Ministry of Education, Hebei Medical University, Shijiazhuang, 050017, PR China.
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12
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Babu FS, Majetschak M. Linopirdine-supplemented resuscitation fluids reduce mortality in a model of ischemia-reperfusion injury induced acute respiratory distress syndrome. Physiol Res 2021; 70:649-953. [PMID: 34062081 PMCID: PMC8820536 DOI: 10.33549/physiolres.934679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 04/29/2021] [Indexed: 11/25/2022] Open
Abstract
Previously, we demonstrated that supplementation of resuscitation fluids with the Kv7 voltage-activated potassium channel inhibitor linopirdine reduces fluid resuscitation requirements and stabilizes hemodynamics in various rat models of hemorrhagic shock. To further evaluate the therapeutic potential of linopirdine, we tested the effects of linopirdine-supplemented resuscitation fluids in a rat model of ischemia-reperfusion injury-induced acute respiratory distress syndrome (ARDS). Ventilated rats underwent unilateral lung ischemia from t=0-75 min, followed by lung reperfusion and fluid resuscitation to a mean arterial blood pressure of 60 mmHg with normal saline (NS, n=9) or NS supplemented with 50 µg/ml linopridine (NS-L), n=7) until t=360 min. As compared with NS, fluid resuscitation with NS-L stabilized blood pressure and reduced fluid requirements by 40% (p<0.05 vs. NS at t=240-360 min). While NS-L did not affect ARDS development, it reduced mortality from 66% with NS to 14% with NS-L (p=0.03, hazard ratio 0.14; 95% confidence interval of the hazard ratio: 0.03-0.65). Median survival time was 240 min with NS and >360 min with NS-L. As compared with NS treated animals that survived the observation period (n=3), however, plasma lactate and creatinine concentrations at t=360 min were higher with NS-L (n=6; p<0.05). Our findings extend therapeutic potential of NS-L from hypovolemic/hemorrhagic shock to hemodynamic instability under normovolemic conditions during organ ischemia-reperfusion injury. Possible adverse effects of NS-L, such as impairment of renal function and/or organ hypoperfusion, require further evaluation in long-term pre-clinical models.
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Affiliation(s)
- F S Babu
- Department of Surgery, Loyola University Chicago, Stritch School of Medicine, Maywood, IL, USA.
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13
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Naffaa MM, Al-Ewaidat OA. Ligand modulation of KCNQ-encoded (K V7) potassium channels in the heart and nervous system. Eur J Pharmacol 2021; 906:174278. [PMID: 34174270 DOI: 10.1016/j.ejphar.2021.174278] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/06/2021] [Accepted: 06/18/2021] [Indexed: 10/21/2022]
Abstract
KCNQ-encoded (KV7) potassium channels are diversely distributed in the human tissues, associated with many physiological processes and pathophysiological conditions. These channels are increasingly used as drug targets for treating diseases. More selective and potent molecules on various types of the KV7 channels are desirable for appropriate therapies. The recent knowledge of the structure and function of human KCNQ-encoded channels makes it more feasible to achieve these goals. This review discusses the role and mechanism of action of many molecules in modulating the function of the KCNQ-encoded potassium channels in the heart and nervous system. The effects of these compounds on KV7 channels help to understand their involvement in many diseases, and to search for more selective and potent ligands to be used in the treatment of many disorders such as various types of cardiac arrhythmias, epilepsy, and pain.
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Affiliation(s)
- Moawiah M Naffaa
- Department of Cell Biology, Duke University School of Medicine, Durham, NC, 27710, USA; Department of Psychology and Neuroscience, Duke University, Durham, NC 27708, USA.
| | - Ola A Al-Ewaidat
- Faculty of Medicine, The University of Jordan, Amman, 11942, Jordan
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14
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Borgini M, Mondal P, Liu R, Wipf P. Chemical modulation of Kv7 potassium channels. RSC Med Chem 2021; 12:483-537. [PMID: 34046626 PMCID: PMC8128042 DOI: 10.1039/d0md00328j] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/01/2020] [Indexed: 01/10/2023] Open
Abstract
The rising interest in Kv7 modulators originates from their ability to evoke fundamental electrophysiological perturbations in a tissue-specific manner. A large number of therapeutic applications are, in part, based on the clinical experience with two broad-spectrum Kv7 agonists, flupirtine and retigabine. Since precise molecular structures of human Kv7 channel subtypes in closed and open states have only very recently started to emerge, computational studies have traditionally been used to analyze binding modes and direct the development of more potent and selective Kv7 modulators with improved safety profiles. Herein, the synthetic and medicinal chemistry of small molecule modulators and the representative biological properties are summarized. Furthermore, new therapeutic applications supported by in vitro and in vivo assay data are suggested.
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Affiliation(s)
- Matteo Borgini
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Pravat Mondal
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Ruiting Liu
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
| | - Peter Wipf
- Department of Chemistry, University of Pittsburgh Pittsburgh PA 15260 USA
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15
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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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16
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van der Horst J, Rognant S, Abbott GW, Ozhathil LC, Hägglund P, Barrese V, Chuang CY, Jespersen T, Davies MJ, Greenwood IA, Gourdon P, Aalkjær C, Jepps TA. Dynein regulates Kv7.4 channel trafficking from the cell membrane. J Gen Physiol 2021; 153:211752. [PMID: 33533890 PMCID: PMC7863719 DOI: 10.1085/jgp.202012760] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Revised: 12/21/2020] [Accepted: 01/08/2021] [Indexed: 12/15/2022] Open
Abstract
The dynein motor protein transports proteins away from the cell membrane along the microtubule network. Recently, we found the microtubule network was important for regulating the membrane abundance of voltage-gated Kv7.4 potassium channels in vascular smooth muscle. Here, we aimed to investigate the influence of dynein on the microtubule-dependent internalization of the Kv7.4 channel. Patch-clamp recordings from HEK293B cells showed Kv7.4 currents were increased after inhibiting dynein function with ciliobrevin D or by coexpressing p50/dynamitin, which specifically interferes with dynein motor function. Mutation of a dynein-binding site in the Kv7.4 C terminus increased the Kv7.4 current and prevented p50 interference. Structured illumination microscopy, proximity ligation assays, and coimmunoprecipitation showed colocalization of Kv7.4 and dynein in mesenteric artery myocytes. Ciliobrevin D enhanced mesenteric artery relaxation to activators of Kv7.2–Kv7.5 channels and increased membrane abundance of Kv7.4 protein in isolated smooth muscle cells and HEK293B cells. Ciliobrevin D failed to enhance the negligible S-1–mediated relaxations after morpholino-mediated knockdown of Kv7.4. Mass spectrometry revealed an interaction of dynein with caveolin-1, confirmed using proximity ligation and coimmunoprecipitation assays, which also provided evidence for interaction of caveolin-1 with Kv7.4, confirming that Kv7.4 channels are localized to caveolae in mesenteric artery myocytes. Lastly, cholesterol depletion reduced the interaction of Kv7.4 with caveolin-1 and dynein while increasing the overall membrane expression of Kv7.4, although it attenuated the Kv7.4 current in oocytes and interfered with the action of ciliobrevin D and channel activators in arterial segments. Overall, this study shows that dynein can traffic Kv7.4 channels in vascular smooth muscle in a mechanism dependent on cholesterol-rich caveolae.
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Affiliation(s)
| | - Salomé Rognant
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Geoffrey W Abbott
- Bioelectricity Laboratory, Department of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA
| | | | - Per Hägglund
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Vincenzo Barrese
- St. George's, University of London, London, UK.,Department of Neuroscience, Reproductive Science and Dentistry, University of Naples "Federico II," Naples, Italy
| | - Christine Y Chuang
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas Jespersen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michael J Davies
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Pontus Gourdon
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Medical Sciences, Lund University, Lund, Sweden
| | - Christian Aalkjær
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.,Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Thomas A Jepps
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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17
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Bercea CI, Cottrell GS, Tamagnini F, McNeish AJ. Omega-3 polyunsaturated fatty acids and hypertension: a review of vasodilatory mechanisms of docosahexaenoic acid and eicosapentaenoic acid. Br J Pharmacol 2021; 178:860-877. [PMID: 33283269 DOI: 10.1111/bph.15336] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 11/27/2020] [Accepted: 11/29/2020] [Indexed: 02/06/2023] Open
Abstract
Hypertension is often characterised by impaired vasodilation involving dysfunction of multiple vasodilatory mechanisms. ω-3 polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) can reduce blood pressure and vasodilation. In the endothelium, DHA and EPA improve function including increased NO bioavailability. However, animal studies show that DHA- and EPA-mediated vasodilation persists after endothelial removal, indicating a role for vascular smooth muscle cells (VSMCs). The vasodilatory effects of ω-3 PUFAs on VSMCs are mediated via opening of large conductance calcium-activated potassium channels (BKCa ), ATP-sensitive potassium channels (KATP ) and possibly members of the Kv 7 family of voltage-activated potassium channels, resulting in hyperpolarisation and relaxation. ω-3 PUFA actions on BKCa and voltage-gated ion channels involve electrostatic interactions that are dependent on the polyunsaturated acyl tail, cis-geometry of these double bonds and negative charge of the carboxyl headgroup. This suggests structural manipulation of ω-3 PUFA could generate novel, targeted, therapeutic leads.
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Affiliation(s)
- Cristiana-Ioana Bercea
- Reading School of Pharmacy, School of Chemistry, Food and Pharmacy, The University of Reading, Reading, UK
| | - Graeme S Cottrell
- Reading School of Pharmacy, School of Chemistry, Food and Pharmacy, The University of Reading, Reading, UK
| | - Francesco Tamagnini
- Reading School of Pharmacy, School of Chemistry, Food and Pharmacy, The University of Reading, Reading, UK
| | - Alister J McNeish
- Reading School of Pharmacy, School of Chemistry, Food and Pharmacy, The University of Reading, Reading, UK
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18
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Li X, Zhang Q, Guo P, Fu J, Mei L, Lv D, Wang J, Lai D, Ye S, Yang H, Guo J. Molecular basis for ligand activation of the human KCNQ2 channel. Cell Res 2021; 31:52-61. [PMID: 32884139 PMCID: PMC7852908 DOI: 10.1038/s41422-020-00410-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 08/14/2020] [Indexed: 01/10/2023] Open
Abstract
The voltage-gated potassium channel KCNQ2 is responsible for M-current in neurons and is an important drug target to treat epilepsy, pain and several other diseases related to neuronal hyper-excitability. A list of synthetic compounds have been developed to directly activate KCNQ2, yet our knowledge of their activation mechanism is limited, due to lack of high-resolution structures. Here, we report cryo-electron microscopy (cryo-EM) structures of the human KCNQ2 determined in apo state and in complex with two activators, ztz240 or retigabine, which activate KCNQ2 through different mechanisms. The activator-bound structures, along with electrophysiology analysis, reveal that ztz240 binds at the voltage-sensing domain and directly stabilizes it at the activated state, whereas retigabine binds at the pore domain and activates the channel by an allosteric modulation. By accurately defining ligand-binding sites, these KCNQ2 structures not only reveal different ligand recognition and activation mechanisms, but also provide a structural basis for drug optimization and design.
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Affiliation(s)
- Xiaoxiao Li
- Department of Biophysics, and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, China
| | - Qiansen Zhang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Peipei Guo
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Jie Fu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Lianghe Mei
- Suzhou Institute of Drug Innovation, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 108 Yuxin Road, Suzhou, Jiangsu, 215123, China
| | - Dashuai Lv
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang, 310058, China
| | - Jiangqin Wang
- Department of Biophysics, and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, China
| | - Dongwu Lai
- Department of Cardiology, Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310016, China
| | - Sheng Ye
- Life Sciences Institute and Innovation Center for Cell Signaling Network, Zhejiang University, Hangzhou, Zhejiang, 310058, China
- School of Life Sciences, Tianjin University, 92 Weijin Road, Nankai District, Tianjin, 300072, China
| | - Huaiyu Yang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China.
| | - Jiangtao Guo
- Department of Biophysics, and Department of Pathology of Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310058, China.
- Department of Cardiology, Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, 310016, China.
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19
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Abstract
Kv7.1-Kv7.5 (KCNQ1-5) K+ channels are voltage-gated K+ channels with major roles in neurons, muscle cells and epithelia where they underlie physiologically important K+ currents, such as neuronal M current and cardiac IKs. Specific biophysical properties of Kv7 channels make them particularly well placed to control the activity of excitable cells. Indeed, these channels often work as 'excitability breaks' and are targeted by various hormones and modulators to regulate cellular activity outputs. Genetic deficiencies in all five KCNQ genes result in human excitability disorders, including epilepsy, arrhythmias, deafness and some others. Not surprisingly, this channel family attracts considerable attention as potential drug targets. Here we will review biophysical properties and tissue expression profile of Kv7 channels, discuss recent advances in the understanding of their structure as well as their role in various neurological, cardiovascular and other diseases and pathologies. We will also consider a scope for therapeutic targeting of Kv7 channels for treatment of the above health conditions.
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20
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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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21
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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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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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Malysz J, Petkov GV. Detrusor Smooth Muscle K V7 Channels: Emerging New Regulators of Urinary Bladder Function. Front Physiol 2020; 11:1004. [PMID: 33041840 PMCID: PMC7526500 DOI: 10.3389/fphys.2020.01004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 07/23/2020] [Indexed: 01/21/2023] Open
Abstract
Relaxation and contraction of the urinary bladder smooth muscle, also known as the detrusor smooth muscle (DSM), facilitate the micturition cycle. DSM contractility depends on cell excitability, which is established by the synchronized activity of multiple diverse ion channels. K+ channels, the largest family of channels, control DSM excitability by maintaining the resting membrane potential and shaping the action potentials that cause the phasic contractions. Among the members of the voltage-gated K+ (KV) channel superfamily, KV type 7 (KV7) channels - KV7.1-KV7.5 members encoded by KCNQ1-KCNQ5 genes - have been recently identified as functional regulators in various cell types including vascular, cardiac, and neuronal cells. Their regulatory roles in DSM, however, are just now emerging and remain to be elucidated. To address this gap, our research group has initiated the systematic investigation of human DSM KV7 channels in collaboration with clinical urologists. In this comprehensive review, we summarize the current understanding of DSM Kv7 channels and highlight recent discoveries in the field. We describe KV7 channel expression profiles at the mRNA and protein levels, and further elaborate on functional effects of KV7 channel selective modulators on DSM excitability, contractility, and intracellular Ca2+ dynamics in animal species along with in vivo studies and the limited data on human DSM. Within each topic, we highlight the main observations, current gaps in knowledge, and most pressing questions and concepts in need of resolution. We emphasize the lack of systematic studies on human DSM KV7 channels that are now actively ongoing in our laboratory.
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Affiliation(s)
- John Malysz
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Georgi V. Petkov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, United States
- Department of Pharmacology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
- Department of Urology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, United States
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24
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Barrese V, Stott JB, Baldwin SN, Mondejar-Parreño G, Greenwood IA. SMIT (Sodium-Myo-Inositol Transporter) 1 Regulates Arterial Contractility Through the Modulation of Vascular Kv7 Channels. Arterioscler Thromb Vasc Biol 2020; 40:2468-2480. [PMID: 32787517 PMCID: PMC7505149 DOI: 10.1161/atvbaha.120.315096] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Supplemental Digital Content is available in the text. Objective: The SMIT1 (sodium:myo-inositol transporter 1) regulates myo-inositol movement into cells and responses to hypertonic stimuli. Alteration of myo-inositol levels has been associated with several diseases, including hypertension, but there is no evidence of a functional role of SMIT1 in the vasculature. Recent evidence showed that in the nervous system SMIT1 interacted and modulated the function of members of the Kv7 family of voltage-gated potassium channels, which are also expressed in the vasculature where they regulate arterial contractility. Therefore, in this study, we evaluated whether SMIT1 was functionally relevant in arterial smooth muscle. Approach and Results: Immunofluorescence and polymerase chain reaction experiments revealed that SMIT1 was expressed in rat renal and mesenteric vascular smooth muscle cells. Isometric tension recordings showed that incubation of renal arteries with raffinose and myo-inositol (which increases SMIT1 expression) reduced the contractile responses to methoxamine, an effect that was abolished by preincubation with the pan-Kv7 blocker linopirdine and by molecular knockdown of Kv7.4 and Kv7.5. Knockdown of SMIT1 increased the contraction of renal arteries induced by methoxamine, impaired the response to the Kv7.2–Kv7.5 activator ML213 but did not interfere with the relaxant responses induced by openers of other potassium channels. Proximity ligation assay showed that SMIT1 interacted with heteromeric channels formed by Kv7.4 and Kv7.5 proteins in both renal and mesenteric vascular smooth muscle cells. Patch-clamp experiments showed that incubation with raffinose plus myo-inositol increased Kv7 currents in vascular smooth muscle cells. Conclusions: SMIT1 protein is expressed in vascular smooth muscle cells where it modulates arterial contractility through an association with Kv7.4/Kv7.5 heteromers.
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Affiliation(s)
- Vincenzo Barrese
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., S.N.B., I.A.G.).,Department of Neuroscience, Reproductive Science and Dentistry, University of Naples Federico II, Italy (V.B.)
| | - Jennifer B Stott
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., S.N.B., I.A.G.)
| | - Samuel N Baldwin
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., S.N.B., I.A.G.)
| | - Gema Mondejar-Parreño
- Department of Pharmacology and Toxicology. School of Medicine, Universidad Complutense de Madrid, Spain (G.M.-P.)
| | - Iain A Greenwood
- Vascular Research Centre, Institute of Molecular & Clinical Sciences, St George's, University of London, United Kingdom (V.B., J.B.S., S.N.B., I.A.G.)
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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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Mondejar-Parreño G, Perez-Vizcaino F, Cogolludo A. Kv7 Channels in Lung Diseases. Front Physiol 2020; 11:634. [PMID: 32676036 PMCID: PMC7333540 DOI: 10.3389/fphys.2020.00634] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/18/2020] [Indexed: 12/23/2022] Open
Abstract
Lung diseases constitute a global health concern causing disability. According to WHO in 2016, respiratory diseases accounted for 24% of world population mortality, the second cause of death after cardiovascular diseases. The Kv7 channels family is a group of voltage-dependent K+ channels (Kv) encoded by KCNQ genes that are involved in various physiological functions in numerous cell types, especially, cardiac myocytes, smooth muscle cells, neurons, and epithelial cells. Kv7 channel α-subunits are regulated by KCNE1–5 ancillary β-subunits, which modulate several characteristics of Kv7 channels such as biophysical properties, cell-location, channel trafficking, and pharmacological sensitivity. Kv7 channels are mainly expressed in two large groups of lung tissues: pulmonary arteries (PAs) and bronchial tubes. In PA, Kv7 channels are expressed in pulmonary artery smooth muscle cells (PASMCs); while in the airway (trachea, bronchus, and bronchioles), Kv7 channels are expressed in airway smooth muscle cells (ASMCs), airway epithelial cells (AEPs), and vagal airway C-fibers (VACFs). The functional role of Kv7 channels may vary depending on the cell type. Several studies have demonstrated that the impairment of Kv7 channel has a strong impact on pulmonary physiology contributing to the pathophysiology of different respiratory diseases such as cystic fibrosis, asthma, chronic obstructive pulmonary disease, chronic coughing, lung cancer, and pulmonary hypertension. Kv7 channels are now recognized as playing relevant physiological roles in many tissues, which have encouraged the search for Kv7 channel modulators with potential therapeutic use in many diseases including those affecting the lung. Modulation of Kv7 channels has been proposed to provide beneficial effects in a number of lung conditions. Therefore, Kv7 channel openers/enhancers or drugs acting partly through these channels have been proposed as bronchodilators, expectorants, antitussives, chemotherapeutics and pulmonary vasodilators.
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Affiliation(s)
- Gema Mondejar-Parreño
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.,Ciber Enfermedades Respiratorias (Ciberes), Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
| | - Francisco Perez-Vizcaino
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.,Ciber Enfermedades Respiratorias (Ciberes), Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
| | - Angel Cogolludo
- Departamento de Farmacología y Toxicología, Facultad de Medicina, Universidad Complutense de Madrid, Madrid, Spain.,Ciber Enfermedades Respiratorias (Ciberes), Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón (IISGM), Madrid, Spain
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27
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Vilela DAD, Silva BAO, Brito MC, Menezes PMN, Bomfim HF, Duarte-Filho LAMDS, Silva TRDS, Ribeiro LADA, Lucchese AM, Silva FS. Lippia alnifolia essential oil induces relaxation on Guinea-pig trachea by multiple pathways. JOURNAL OF ETHNOPHARMACOLOGY 2020; 246:112162. [PMID: 31419501 DOI: 10.1016/j.jep.2019.112162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 07/22/2019] [Accepted: 08/11/2019] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Lippia alnifolia Mart. & Schauer, known as "alecrim-do-mato", "alecrim-de-vaqueiro" and "pedrécio", is used in folk medicine as antiseptic and to treat diseases that affect respiratory system, like bronchitis and asthma. AIM OF THE STUDY The aim of this work was to investigate the spasmolytic activity and relaxant mechanism of the Lippia alnifolia essential oil (EOLA) on isolated guinea-pig trachea and to correlate with its use in folk medicine. MATERIALS AND METHODS Leaves from L. alnifolia were collected in Pico das Almas, Chapada Diamantina, situated in the city of Rio de Contas, Bahia, Brazil. EOLA was extracted by hydrodistillation, analyzed by GC/FID and GC/MS and the volatile constituents were identified. Spasmolytic activity was assayed in isolated guinea-pig trachea pre-contracted with carbachol 1 μM or histamine 10 μM. Relaxant mechanism of EOLA was determined comparing concentration-response curves in the presence or absence of different blockers. RESULTS Chemical analysis revealed the presence of carvone (60 ± 0.8%) as major constituent. EOLA (1-243 μg/mL) relaxed isolated guinea-pig trachea pre-contracted with carbachol 1 μM [EC50 = 53.36 (44.75-63.51) μg/mL] or histamine 10 μM [EC50 = 5.42 (4.42-6.65) μg/mL]. The pre-incubation of 4-aminopyridine in histamine-induced contractions did not alter significantly the relaxant effect of EOLA. However, the presence of cesium chloride, glibenclamide, tetraethylammonium, propranolol, indomethacin, dexamethasone, hexamethonium, atropine, L-NAME, methylene blue or ODQ reduced EOLA relaxant effect. EOLA 18 μg/mL pre-incubation in calcium-free medium reduced histamine-evoked contractions, but did not alter histamine contractions in the presence of nifedipine. CONCLUSIONS Lippia alnifolia essential oil has spasmolytic activity on isolated guinea-pig trachea and its mechanism of action possibly involves the activation of multiple signal transduction pathways, which culminate in potassium channels activation and cytosolic calcium reduction.
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Affiliation(s)
| | | | - Mariana Coelho Brito
- Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | | | - Horácio Freitas Bomfim
- Laboratório de Química de Produtos Naturais e Bioativos, Departamento de Ciências Exatas, Universidade Estadual de Feira de Santana (UEFS), Brazil.
| | | | | | - Luciano Augusto de Araújo Ribeiro
- Pós-graduação em Biociências, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil; Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | - Angélica Maria Lucchese
- Laboratório de Química de Produtos Naturais e Bioativos, Departamento de Ciências Exatas, Universidade Estadual de Feira de Santana (UEFS), Brazil.
| | - Fabrício Souza Silva
- Pós-graduação em Biociências, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil; Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
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28
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Wei AD, Ramirez JM. Presynaptic Mechanisms and KCNQ Potassium Channels Modulate Opioid Depression of Respiratory Drive. Front Physiol 2019; 10:1407. [PMID: 31824331 PMCID: PMC6882777 DOI: 10.3389/fphys.2019.01407] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 10/31/2019] [Indexed: 01/02/2023] Open
Abstract
Opioid-induced respiratory depression (OIRD) is the major cause of death associated with opioid analgesics and drugs of abuse, but the underlying cellular and molecular mechanisms remain poorly understood. We investigated opioid action in vivo in unanesthetized mice and in in vitro medullary slices containing the preBötzinger Complex (preBötC), a locus critical for breathing and inspiratory rhythm generation. Although hypothesized as a primary mechanism, we found that mu-opioid receptor (MOR1)-mediated GIRK activation contributed only modestly to OIRD. Instead, mEPSC recordings from genetically identified Dbx1-derived interneurons, essential for rhythmogenesis, revealed a prevalent presynaptic mode of action for OIRD. Consistent with MOR1-mediated suppression of presynaptic release as a major component of OIRD, Cacna1a KO slices lacking P/Q-type Ca2+ channels enhanced OIRD. Furthermore, OIRD was mimicked and reversed by KCNQ potassium channel activators and blockers, respectively. In vivo whole-body plethysmography combined with systemic delivery of GIRK- and KCNQ-specific potassium channel drugs largely recapitulated these in vitro results, and revealed state-dependent modulation of OIRD. We propose that respiratory failure from OIRD results from a general reduction of synaptic efficacy, leading to a state-dependent collapse of rhythmic network activity.
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Affiliation(s)
- Aguan D. Wei
- Seattle Children’s Research Institute, Center for Integrative Brain Research, Seattle, WA, United States
- Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA, United States
| | - Jan-Marino Ramirez
- Seattle Children’s Research Institute, Center for Integrative Brain Research, Seattle, WA, United States
- Department of Neurological Surgery, University of Washington School of Medicine, Seattle, WA, United States
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29
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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: 29] [Impact Index Per Article: 5.8] [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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30
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Stott JB, Barrese V, Suresh M, Masoodi S, Greenwood IA. Investigating the Role of G Protein βγ in Kv7-Dependent Relaxations of the Rat Vasculature. Arterioscler Thromb Vasc Biol 2019; 38:2091-2102. [PMID: 30002060 DOI: 10.1161/atvbaha.118.311360] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Objective- In renal arteries, inhibitors of G protein βγ subunits (Gβγ) reduce Kv7 activity and inhibit Kv7-dependent receptor-mediated vasorelaxations. However, the mechanisms underlying receptor-mediated relaxation are artery specific. Consequently, the aim of this study was to ascertain the role of Gβγ in Kv7-dependent vasorelaxations of the rat vasculature. Approach and Results- Isometric tension recording was performed in isolated rat renal, mesenteric, and cerebral arteries to study isoproterenol and calcitonin gene-related peptide relaxations. Kv7.4 was knocked down via morpholino transfection while inhibition of Gβγ was investigated with gallein and M119K. Proximity ligation assay was performed on isolated myocytes to study the association between Kv7.4 and G protein β subunits or signaling intermediaries. Isoproterenol or calcitonin gene-related peptide-induced relaxations were attenuated by Kv7.4 knockdown in all arteries studied. Inhibition of Gβγ with gallein or M119K had no effect on isoproterenol-mediated relaxations in mesenteric artery but had a marked effect on calcitonin gene-related peptide-induced responses in mesenteric artery and cerebral artery and isoproterenol responses in renal artery. Isoproterenol increased association with Kv7.4 and Rap1a in mesenteric artery which were not sensitive to gallein, whereas in renal artery, isoproterenol increased Kv7.4-AKAP (A-kinase anchoring protein) associations in a gallein-sensitive manner. Conclusions- The Gβγ-Kv7 relationship differs between vessels and is an essential requirement for AKAP, but not Rap-mediated regulation of the channel.
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Affiliation(s)
- Jennifer B Stott
- From the Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, United Kingdom
| | - Vincenzo Barrese
- From the Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, United Kingdom
| | - Malavika Suresh
- From the Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, United Kingdom
| | - Shirou Masoodi
- From the Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, United Kingdom
| | - Iain A Greenwood
- From the Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George's University of London, United Kingdom
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Abstract
Ion channels play as a pivotal role in hypertension in the processes of maintenance of vascular tone and sympathetic excitement of hypertension. The Kv10.2 channel (encoded by the Kcnh5 gene) belongs to the EAG voltage-gated superfamily. It is distributed widely in the brain, such as the hippocampus, the cortex, and the olfactory bulb. To date, the expression of Kv10.2 in central nervous system nuclei that regulates cardiovascular function and its inter-relationship with hypertension are still unclear. Here, electric foot-shock stressors with noise were used to establish the stress-induced hypertensive (SIH) rat model. The expression of Kv10.2 in the rostral ventrolateral medulla, the nucleus tractus solitarius, and the paraventricular nucleus (PVN) was examined by immunohistochemical staining and western blots. The following results were obtained: (a) the expression level of Kv10.2 was increased obviously in the paraventricular nucleus of SIH rats, whereas no significant difference was found in the rostral ventrolateral medulla and the nucleus tractus solitarius. (b) Kv10.2 was located in neurons. (c) Vesicular glutamate transporter 1 as a protein mark of glutamate neurons was increased in the paraventricular nucleus of the SIH group. (d) The expression of vesicular glutamate transporter 1 protein in neurons was significantly decreased when the Kcnh5 gene was knocked down by small interfering RNA in vitro. These findings indicate that the changes in Kv10.2 may be related to SIH, which may provide a potential avenue for further investigation of SIH.
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Dogan MF, Yildiz O, Arslan SO, Ulusoy KG. Potassium channels in vascular smooth muscle: a pathophysiological and pharmacological perspective. Fundam Clin Pharmacol 2019; 33:504-523. [PMID: 30851197 DOI: 10.1111/fcp.12461] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 02/28/2019] [Accepted: 03/07/2019] [Indexed: 12/23/2022]
Abstract
Potassium (K+ ) ion channel activity is an important determinant of vascular tone by regulating cell membrane potential (MP). Activation of K+ channels leads to membrane hyperpolarization and subsequently vasodilatation, while inhibition of the channels causes membrane depolarization and then vasoconstriction. So far five distinct types of K+ channels have been identified in vascular smooth muscle cells (VSMCs): Ca+2 -activated K+ channels (BKC a ), voltage-dependent K+ channels (KV ), ATP-sensitive K+ channels (KATP ), inward rectifier K+ channels (Kir ), and tandem two-pore K+ channels (K2 P). The activity and expression of vascular K+ channels are changed during major vascular diseases such as hypertension, pulmonary hypertension, hypercholesterolemia, atherosclerosis, and diabetes mellitus. The defective function of K+ channels is commonly associated with impaired vascular responses and is likely to become as a result of changes in K+ channels during vascular diseases. Increased K+ channel function and expression may also help to compensate for increased abnormal vascular tone. There are many pharmacological and genotypic studies which were carried out on the subtypes of K+ channels expressed in variable amounts in different vascular beds. Modulation of K+ channel activity by molecular approaches and selective drug development may be a novel treatment modality for vascular dysfunction in the future. This review presents the basic properties, physiological functions, pathophysiological, and pharmacological roles of the five major classes of K+ channels that have been determined in VSMCs.
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Affiliation(s)
- Muhammed Fatih Dogan
- Department of Pharmacology, Ankara Yildirim Beyazit University, Bilkent, Ankara, 06010, Turkey
| | - Oguzhan Yildiz
- Department of Pharmacology, Gulhane Faculty of Medicine, University of Health Sciences, Etlik, Ankara, 06170, Turkey
| | - Seyfullah Oktay Arslan
- Department of Pharmacology, Ankara Yildirim Beyazit University, Bilkent, Ankara, 06010, Turkey
| | - Kemal Gokhan Ulusoy
- Department of Pharmacology, Gulhane Faculty of Medicine, University of Health Sciences, Etlik, Ankara, 06170, Turkey
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Lawson K. Pharmacology and clinical applications of flupirtine: Current and future options. World J Pharmacol 2019; 8:1-13. [DOI: 10.5497/wjp.v8.i1.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/17/2018] [Accepted: 01/05/2019] [Indexed: 02/06/2023] Open
Abstract
Flupirtine is the first representative in a class of triaminopyridines that exhibits pharmacological properties leading to the suppression of over-excitability of neuronal and non-neuronal cells. Consequently, this drug has been used as a centrally acting analgesic in patients with a range of acute and persistent pain conditions without the adverse effects characteristic of opioids and non-steroidal anti-inflammatory drug and is well tolerated. The pharmacological profile exhibited involves actions on several cellular targets, including Kv7 channels, G-protein-regulated inwardly rectifying K channels and γ-aminobutyric acid type A receptors, but also there is evidence of additional as yet unidentified mechanisms of action involved in the effects of flupirtine. Flupirtine has exhibited effects in a range of cells and tissues related to the locations of these targets. In additional to analgesia, flupirtine has demonstrated pharmacological properties consistent with use as an anticonvulsant, a neuroprotectant, skeletal and smooth muscle relaxant, in treatment of auditory and visual disorders, and treatment of memory and cognitive impairment. Flupirtine is providing important information and clues regarding novel mechanistic approaches to the treatment of a range of clinical conditions involving hyper-excitability of cells. Identification of molecules exhibiting specificity for the pharmacological targets (e.g., Kv7 isoforms) involved in the actions of flupirtine will provide further insight into clinical applications. Whether the broad-spectrum pharmacology of flupirtine or target-specific actions is preferential to gain benefit, especially in complex clinical conditions, requires further investigation. This review will consider recent advancement in understanding of the pharmacological profile and related clinical applications of flupirtine.
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Affiliation(s)
- Kim Lawson
- Department of Biosciences and Chemistry, Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield S1 1WB, United Kingdom
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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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de Jong IEM, Jepps TA. Impaired Kv7 channel function in cerebral arteries of a tauopathy mouse model (rTg4510). Physiol Rep 2018; 6:e13920. [PMID: 30548427 PMCID: PMC6289909 DOI: 10.14814/phy2.13920] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/01/2018] [Accepted: 10/18/2018] [Indexed: 01/20/2023] Open
Abstract
In tauopathies, such as Alzheimer's disease with or without concomitant amyloid β plaques, cerebral arteries display pathological remodeling, leading to reduced brain tissue oxygenation and cognitive impairment. The precise mechanisms that underlie this vascular dysfunction remain unclear. Kv7 voltage-dependent K+ channels contribute to the development of myogenic tone in rat cerebral arteries. Thus, we hypothesized that Kv7 channel function would be impaired in the cerebral arteries of a tauopathy mouse model (rTg4510), which might underlie cerebral hypoperfusion associated with the development of neurofibrillary tangles in tauopathies. To test our hypothesis we performed wire myography and quantitative PCR on cerebral arteries, mesenteric arteries and the inferior frontotemporal region of the brain surrounding the middle cerebral artery from tau transgenic mice (rTg4510) and aged-matched controls. We also performed whole-cell patch clamp experiments on HEK293 cells stably expressing Kv7.4. Here, we show that Kv7 channels are functionally impaired in the cerebral arteries of rTg4510 mice, but not in mesenteric arteries from the same mice. The quantitative PCR analysis of the cerebral arteries found no change in the expression of the genes encoding the Kv7 channel α-subunits, however, we found reduced expression of the ancillary subunit, KCNE5 (also termed KCNE1L), in the cerebral arteries of rTg4510 mice. In the brain, rTg4510 mice showed reduced expression of Kv7.3, Kv7.5, and Kv2.1. Co-expression of KCNE5 with Kv7.4 in HEK293 cells produced larger currents at voltages >0 mV and increased the deactivation time for the Kv7.4 channel. Thus, our results demonstrate that Kv7 channel function is attenuated in the cerebral arteries of Tg4510 mice, which may result from decreased KCNE5 expression. Reduced Kv7 channel function might contribute to cerebral hypoperfusion in tauopathies, such as Alzheimer's disease.
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Affiliation(s)
| | - Thomas A. Jepps
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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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: 13] [Impact Index Per Article: 2.2] [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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Kim B, Jo C, Choi HY, Lee K. Prunetin Relaxed Isolated Rat Aortic Rings by Blocking Calcium Channels. Molecules 2018; 23:molecules23092372. [PMID: 30227625 PMCID: PMC6225200 DOI: 10.3390/molecules23092372] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 11/26/2022] Open
Abstract
Prunetin, a component of herbal medicines and various foods, such as pea, peach, cherry, and Prunus yedoensis, is a useful pharmacological compound. We previously reported the potent vasorelaxant effect of the bark of P. yedoensis. Therefore, we investigated the vasorelaxant activities of prunetin on isolated rat aortic rings and hypotensive activity on spontaneously hypertensive rats (SHR) in this study. In the present study, prunetin (1–30 μg/mL) relaxed isolated rat aortic rings pre-contracted by phenylephrine (PE) in a concentration-dependent manner. Pre-incubation with prunetin (3 and 10 μg/mL) inhibited vasoconstriction induced by the supply of Ca2+ in rat aortic rings pre-contracted with PE or KCl in a Ca2+-free Krebs–Henseleit (KH) buffer. Prunetin (10 μg/mL) pre-treatment also inhibited caffeine-induced contraction of aortic rings in a Ca2+-free KH buffer. To investigate the hypotensive effect of prunetin, the systolic blood pressure (SBP) of the SHR was measured by using a tail cuff assay. The SBP of SHR was significantly lower in the prunetin (25 mg/kg)-treated group. These results suggested that prunetin decreased blood pressure and relaxed blood vessels by blocking receptor-operated calcium channels, voltage-dependent calcium channels, and ryanodine receptor channels.
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Affiliation(s)
- Bumjung Kim
- Department of Herbology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea.
| | - Cheolmin Jo
- Department of Herbology, Graduate School, Kyung Hee University, Seoul 02447, Korea.
| | - Ho-Young Choi
- Department of Herbology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea.
| | - Kyungjin Lee
- Department of Herbology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea.
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Mechanisms of PKA-Dependent Potentiation of Kv7.5 Channel Activity in Human Airway Smooth Muscle Cells. Int J Mol Sci 2018; 19:ijms19082223. [PMID: 30061510 PMCID: PMC6121446 DOI: 10.3390/ijms19082223] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 07/26/2018] [Accepted: 07/27/2018] [Indexed: 12/18/2022] Open
Abstract
β-adrenergic receptor (βAR) activation promotes relaxation of both vascular and airway smooth muscle cells (VSMCs and ASMCs, respectively), though the signaling mechanisms have not been fully elucidated. We previously found that the activity of Kv7.5 voltage-activated potassium channels in VSMCs is robustly enhanced by activation of βARs via a mechanism involving protein kinase A (PKA)-dependent phosphorylation. We also found that enhancement of Kv7 channel activity in ASMCs promotes airway relaxation. Here we provide evidence that Kv7.5 channels are natively expressed in primary cultures of human ASMCs and that they conduct currents which are robustly enhanced in response to activation of the βAR/cyclic adenosine monophosphate (cAMP)/PKA pathway. MIT Scansite software analysis of putative PKA phosphorylation sites on Kv7.5 identified 8 candidate serine or threonine residues. Each residue was individually mutated to an alanine to prevent its phosphorylation and then tested for responses to βAR activation or to stimuli that elevate cAMP levels. Only the mutation of serine 53 (S53A), located on the amino terminus of Kv7.5, significantly reduced the increase in Kv7.5 current in response to these stimuli. A phospho-mimic mutation (S53D) exhibited characteristics of βAR-activated Kv7.5. Serine-to-alanine mutations of 6 putative PKA phosphorylation sites on the Kv7.5 C-terminus, individually or in combination, did not significantly reduce the enhancement of the currents in response to forskolin treatment (to elevate cAMP levels). We conclude that phosphorylation of S53 on the amino terminus of Kv7.5 is essential for PKA-dependent enhancement of channel activity in response to βAR activation in vascular and airway smooth muscle cells.
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Luna-Vázquez FJ, Ibarra-Alvarado C, Camacho-Corona MDR, Rojas-Molina A, Rojas-Molina JI, García A, Bah M. Vasodilator Activity of Compounds Isolated from Plants Used in Mexican Traditional Medicine. Molecules 2018; 23:molecules23061474. [PMID: 29912156 PMCID: PMC6100030 DOI: 10.3390/molecules23061474] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 12/31/2022] Open
Abstract
Arterial hypertension is one of the main risk factors in the development of cardiovascular diseases. Therefore, it is important to look for new drugs to treat hypertension. In this study, we carried out the screening of 19 compounds (triterpenes, diterpenes, sesquiterpenes, lignans, and flavonoids) isolated from 10 plants used in Mexican traditional medicine to determine whether they elicited vascular smooth muscle relaxation and, therefore, could represent novel anti-hypertension drug candidates. The vasorelaxant activity of these compounds was evaluated on the isolated rat aorta assay and the results obtained from this evaluation showed that three compounds induced a significant vasodilatory effect: meso-dihydroguaiaretic acid [half maximal effective concentration (EC50), 49.9 ± 11.2 µM; maximum effect (Emax), 99.8 ± 2.7%]; corosolic acid (EC50, 108.9 ± 6.7 µM; Emax, 96.4 ± 4.2%); and 5,8,4′-trihydroxy-3,7-dimethoxyflavone (EC50, 122.3 ± 7.6 µM; Emax, 99.5 ± 5.4%). Subsequently, involvement of the NO/cyclic guanosine monophosphate (cGMP) and H2S/ATP-sensitive potassium channel (KATP) pathways on the vasodilator activity of these compounds was assessed. The results derived from this analysis showed that the activation of both pathways contributes to the vasorelaxant effect of corosolic acid. On the other hand, the vasodilator effect of meso-dihydroguaiaretic acid and 5,8,4′-trihydroxy-3,7-dimethoxyflavone, partly involves stimulation of the NO/cGMP pathway. However, these compounds also showed an important endothelium-independent vasorelaxant effect, whose mechanism of action remains to be clarified. This study indicates that meso-dihydroguaiaretic acid, corosolic acid, and 5,8,4′-trihydroxy-3,7-dimethoxyflavone could be used as lead compounds for the synthesis of new derivatives with a higher potency to be developed as drugs for the prevention and treatment of cardiovascular diseases.
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Affiliation(s)
- Francisco J Luna-Vázquez
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, C.P. 76010 Querétaro, Mexico.
| | - César Ibarra-Alvarado
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, C.P. 76010 Querétaro, Mexico.
| | - María Del Rayo Camacho-Corona
- Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, San Nicolás de los Garza, CP 66451 Nuevo León, Mexico.
| | - Alejandra Rojas-Molina
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, C.P. 76010 Querétaro, Mexico.
| | - J Isela Rojas-Molina
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, C.P. 76010 Querétaro, Mexico.
| | - Abraham García
- Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, San Nicolás de los Garza, CP 66451 Nuevo León, Mexico.
| | - Moustapha Bah
- Laboratorio de Investigación Química y Farmacológica de Productos Naturales, Facultad de Química, Universidad Autónoma de Querétaro, C.P. 76010 Querétaro, Mexico.
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Du X, Gao H, Jaffe D, Zhang H, Gamper N. M-type K + channels in peripheral nociceptive pathways. Br J Pharmacol 2018; 175:2158-2172. [PMID: 28800673 PMCID: PMC5980636 DOI: 10.1111/bph.13978] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 07/17/2017] [Accepted: 08/03/2017] [Indexed: 12/22/2022] Open
Abstract
Pathological pain is a hyperexcitability disorder. Since the excitability of a neuron is set and controlled by a complement of ion channels it expresses, in order to understand and treat pain, we need to develop a mechanistic insight into the key ion channels controlling excitability within the mammalian pain pathways and how these ion channels are regulated and modulated in various physiological and pathophysiological settings. In this review, we will discuss the emerging data on the expression in pain pathways, functional role and modulation of a family of voltage-gated K+ channels called 'M channels' (KCNQ, Kv 7). M channels are increasingly recognized as important players in controlling pain signalling, especially within the peripheral somatosensory system. We will also discuss the therapeutic potential of M channels as analgesic drug targets. LINKED ARTICLES This article is part of a themed section on Recent Advances in Targeting Ion Channels to Treat Chronic Pain. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.12/issuetoc/.
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Affiliation(s)
- Xiaona Du
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
| | - Haixia Gao
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
- School of Biomedical Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsUK
| | - David Jaffe
- Department of Biology, UTSA Neurosciences InstituteUniversity of Texas at San AntonioSan AntonioTXUSA
| | - Hailin Zhang
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
| | - Nikita Gamper
- Department of Pharmacology, The Key Laboratory of Neural and Vascular Biology, Ministry of EducationHebei Medical UniversityShijiazhuangChina
- The Key Laboratory of New Drug Pharmacology and ToxicologyShijiazhuangHebei ProvinceChina
- School of Biomedical Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsUK
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Eid BG, Gurney AM. Zinc pyrithione activates K+ channels and hyperpolarizes the membrane of rat pulmonary artery smooth muscle cells. PLoS One 2018; 13:e0192699. [PMID: 29474372 PMCID: PMC5824988 DOI: 10.1371/journal.pone.0192699] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 01/29/2018] [Indexed: 01/09/2023] Open
Abstract
The membrane potential helps determine pulmonary artery smooth muscle cell (PASMC) contraction. The Kv7 channel activators, retigabine and flupirtine, are thought to dilate pulmonary arteries by hyperpolarising PASMC. Zinc pyrithione activates Kv7 channels by a mechanism distinct from retigabine and with different Kv7 subunit selectivity. This study aimed to determine if zinc pyrithione selectively activates Kv7 channels in rat PASMC to evoke pulmonary artery dilation. Zinc pyrithione relaxed pulmonary arteries with half-maximal effect at 4.3μM. At 10μM it activated pronounced voltage-dependent K+ current and hyperpolarized PASMCs by around 10mV. Tetraethylammonium ions (TEA, 10mM) and paxilline (1μM) abolished both the current and hyperpolarisation. XE991 (10μM) blocked the hyperpolarization and reduced the current by 30%. Iberiotoxin (50nM) had no effect on the hyperpolarisation, but reduced the current by 40%. The XE991-sensitive current activated with an exponential time course (time constant 17ms), whereas the iberiotoxin-sensitive current followed a bi-exponential time course (time constants 6 and 57ms), suggesting that the drugs blocked different components of the zinc pyrithione-induced current. Zinc pyrithione therefore appears to activate at least two types of K+ channel in PASMC; an XE991, TEA and paxilline-sensitive Kv7 channel and a TEA, paxilline and iberiotoxin-sensitive BKCa channel. Both could contribute to the relaxing effect of zinc pyrithione on pulmonary artery.
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Affiliation(s)
- Basma G. Eid
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Alison M. Gurney
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
- * E-mail:
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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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43
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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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44
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Fosmo AL, Skraastad ØB. The Kv7 Channel and Cardiovascular Risk Factors. Front Cardiovasc Med 2017; 4:75. [PMID: 29259974 PMCID: PMC5723334 DOI: 10.3389/fcvm.2017.00075] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 11/21/2017] [Indexed: 12/30/2022] Open
Abstract
Potassium channels play a pivotal role in the regulation of excitability in cells such as neurons, cardiac myocytes, and vascular smooth muscle cells. The KCNQ (Kv7) family of voltage-activated K+ channels hyperpolarizes the cell and stabilizes the membrane potential. Here, we outline how Kv7 channel activity may contribute to the development of the cardiovascular risk factors such as hypertension, diabetes, and obesity. Questions and hypotheses regarding previous and future research have been raised. Alterations in the Kv7 channel may contribute to the development of cardiovascular disease (CVD). Pharmacological modification of Kv7 channels may represent a possible treatment for CVD in the future.
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Affiliation(s)
- Andreas L Fosmo
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Øyvind B Skraastad
- Division of Physiology, Department of Molecular Medicine, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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45
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Tommiska J, Känsäkoski J, Skibsbye L, Vaaralahti K, Liu X, Lodge EJ, Tang C, Yuan L, Fagerholm R, Kanters JK, Lahermo P, Kaunisto M, Keski-Filppula R, Vuoristo S, Pulli K, Ebeling T, Valanne L, Sankila EM, Kivirikko S, Lääperi M, Casoni F, Giacobini P, Phan-Hug F, Buki T, Tena-Sempere M, Pitteloud N, Veijola R, Lipsanen-Nyman M, Kaunisto K, Mollard P, Andoniadou CL, Hirsch JA, Varjosalo M, Jespersen T, Raivio T. Two missense mutations in KCNQ1 cause pituitary hormone deficiency and maternally inherited gingival fibromatosis. Nat Commun 2017; 8:1289. [PMID: 29097701 PMCID: PMC5668380 DOI: 10.1038/s41467-017-01429-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2017] [Accepted: 09/14/2017] [Indexed: 01/05/2023] Open
Abstract
Familial growth hormone deficiency provides an opportunity to identify new genetic causes of short stature. Here we combine linkage analysis with whole-genome resequencing in patients with growth hormone deficiency and maternally inherited gingival fibromatosis. We report that patients from three unrelated families harbor either of two missense mutations, c.347G>T p.(Arg116Leu) or c.1106C>T p.(Pro369Leu), in KCNQ1, a gene previously implicated in the long QT interval syndrome. Kcnq1 is expressed in hypothalamic GHRH neurons and pituitary somatotropes. Co-expressing KCNQ1 with the KCNE2 β-subunit shows that both KCNQ1 mutants increase current levels in patch clamp analyses and are associated with reduced pituitary hormone secretion from AtT-20 cells. In conclusion, our results reveal a role for the KCNQ1 potassium channel in the regulation of human growth, and show that growth hormone deficiency associated with maternally inherited gingival fibromatosis is an allelic disorder with cardiac arrhythmia syndromes caused by KCNQ1 mutations.
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Affiliation(s)
- Johanna Tommiska
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland.,Children's Hospital, Pediatric Research Center, Helsinki University Central Hospital (HUCH), 00029, Helsinki, Finland
| | - Johanna Känsäkoski
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Lasse Skibsbye
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Kirsi Vaaralahti
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Xiaonan Liu
- Institute of Biotechnology, Biocenter 3, University of Helsinki, 00014, Helsinki, Finland
| | - Emily J Lodge
- Centre for Craniofacial and Regenerative Biology, King's College London, Floor 27 Tower Wing, Guy's Campus, London, SE1 9RT, UK
| | - Chuyi Tang
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Lei Yuan
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Rainer Fagerholm
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland.,Department of Obstetrics and Gynecology, HUCH, 00029, Helsinki, Finland
| | - Jørgen K Kanters
- Laboratory of Experimental Cardiology, Department of Biomedical Sciences, University of Copenhagen, 22000, Copenhagen, Denmark.,Department of Cardiology, Herlev & Gentofte University Hospitals, University of Copenhagen, 22000, Copenhagen, Denmark
| | - Päivi Lahermo
- Institute for Molecular Medicine Finland (FIMM), Helsinki Institute of Life Science HiLIFE, University of Helsinki, 00014, Helsinki, Finland
| | - Mari Kaunisto
- Institute for Molecular Medicine Finland (FIMM), Helsinki Institute of Life Science HiLIFE, University of Helsinki, 00014, Helsinki, Finland
| | | | - Sanna Vuoristo
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Kristiina Pulli
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Tapani Ebeling
- Department of Medicine, Oulu University Hospital, Finland and Research Unit of Internal Medicine, University of Oulu, 90014, Oulu, Finland
| | - Leena Valanne
- Helsinki Medical Imaging Center, HUCH, 00029, Helsinki, Finland
| | | | - Sirpa Kivirikko
- Department of Clinical Genetics, HUCH, 00029, Helsinki, Finland
| | - Mitja Lääperi
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland
| | - Filippo Casoni
- Inserm U1172, Jean-Pierre Aubert Research Center, Development and Plasticity of the Neuroendocrine Brain, 59045, Lille, France.,University of Lille, School of Medicine, 59045, Lille, France
| | - Paolo Giacobini
- Inserm U1172, Jean-Pierre Aubert Research Center, Development and Plasticity of the Neuroendocrine Brain, 59045, Lille, France.,University of Lille, School of Medicine, 59045, Lille, France
| | - Franziska Phan-Hug
- Pediatrics, Division of Pediatric Endocrinology, Diabetology and Obesity, University Hospital Lausanne (CHUV), 1011, Lausanne, Switzerland
| | - Tal Buki
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, 69978, Ramat Aviv, Israel
| | - Manuel Tena-Sempere
- Department of Cell Biology, Physiology and Immunology, University of Córdoba, 14071, Cordoba, Spain.,Instituto Maimonides de Investigacion Biomedica (IMIBIC/HURS), 14004, Cordoba, Spain.,CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Nelly Pitteloud
- Pediatrics, Division of Pediatric Endocrinology, Diabetology and Obesity, University Hospital Lausanne (CHUV), 1011, Lausanne, Switzerland
| | - Riitta Veijola
- Department of Children and Adolescents, Oulu University Hospital, 90029, Oulu, Finland.,Department of Pediatrics, PEDEGO Research Center, Medical Research Center, University of Oulu, 90014, Oulu, Finland
| | - Marita Lipsanen-Nyman
- Children's Hospital, Pediatric Research Center, Helsinki University Central Hospital (HUCH), 00029, Helsinki, Finland
| | - Kari Kaunisto
- Department of Children and Adolescents, Oulu University Hospital, 90029, Oulu, Finland
| | - Patrice Mollard
- IGF, CNRS, INSERM, Univ. Montpellier, F-34094, Montpellier, France
| | - Cynthia L Andoniadou
- Centre for Craniofacial and Regenerative Biology, King's College London, Floor 27 Tower Wing, Guy's Campus, London, SE1 9RT, UK.,Department of Internal Medicine III, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany
| | - Joel A Hirsch
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Institute of Structural Biology, 69978, Ramat Aviv, Israel
| | - Markku Varjosalo
- Institute of Biotechnology, Biocenter 3, University of Helsinki, 00014, Helsinki, Finland
| | - Thomas Jespersen
- Department of Biomedical Sciences, University of Copenhagen, 2200, Copenhagen N, Denmark
| | - Taneli Raivio
- Faculty of Medicine, Department of Physiology, University of Helsinki, 00014, Helsinki, Finland. .,Children's Hospital, Pediatric Research Center, Helsinki University Central Hospital (HUCH), 00029, Helsinki, Finland.
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46
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Potassium channels modulate the action but not the synthesis of hydrogen sulfide in rat corpus cavernosum. Life Sci 2017; 189:39-43. [DOI: 10.1016/j.lfs.2017.09.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 08/14/2017] [Accepted: 09/08/2017] [Indexed: 02/05/2023]
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47
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Provence A, Angoli D, Petkov GV. K V7 Channel Pharmacological Activation by the Novel Activator ML213: Role for Heteromeric K V7.4/K V7.5 Channels in Guinea Pig Detrusor Smooth Muscle Function. J Pharmacol Exp Ther 2017; 364:131-144. [PMID: 29084816 DOI: 10.1124/jpet.117.243162] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 10/20/2017] [Indexed: 01/12/2023] Open
Abstract
Voltage-gated KV7 channels (KV7.1 to KV7.5) are important regulators of the cell membrane potential in detrusor smooth muscle (DSM) of the urinary bladder. This study sought to further the current knowledge of KV7 channel function at the molecular, cellular, and tissue levels in combination with pharmacological tools. We used isometric DSM tension recordings, ratiometric fluorescence Ca2+ imaging, amphotericin-B perforated patch-clamp electrophysiology, and in situ proximity ligation assay (PLA) in combination with the novel compound N-(2,4,6-trimethylphenyl)-bicyclo[2.2.1]heptane-2-carboxamide (ML213), an activator of KV7.2, KV7.4, and KV7.5 channels, to examine their physiologic roles in guinea pig DSM function. ML213 caused a concentration-dependent (0.1-30 µM) inhibition of spontaneous phasic contractions in DSM isolated strips; effects blocked by the KV7 channel inhibitor XE991 (10 µM). ML213 (0.1-30 µM) also reduced pharmacologically induced and nerve-evoked contractions in DSM strips. Consistently, ML213 (10 µM) decreased global intracellular Ca2+ concentrations in Fura-2-loaded DSM isolated strips. Perforated patch-clamp electrophysiology revealed that ML213 (10 µM) caused an increase in the amplitude of whole-cell KV7 currents. Further, in current-clamp mode of the perforated patch clamp, ML213 hyperpolarized DSM cell membrane potential in a manner reversible by washout or XE991 (10 µM), consistent with ML213 activation of KV7 channel currents. Preapplication of XE991 (10 µM) not only depolarized the DSM cells, but also blocked ML213-induced hyperpolarization, confirming ML213 selectivity for KV7 channel subtypes. In situ PLA revealed colocalization and expression of heteromeric KV7.4/KV7.5 channels in DSM isolated cells. These combined results suggest that ML213-sensitive KV7.4- and KV7.5-containing channels are essential regulators of DSM excitability and contractility.
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Affiliation(s)
- Aaron Provence
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina (A.P., D.A., G.V.P.); and Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee (G.V.P.)
| | - Damiano Angoli
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina (A.P., D.A., G.V.P.); and Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee (G.V.P.)
| | - Georgi V Petkov
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina (A.P., D.A., G.V.P.); and Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, Tennessee (G.V.P.)
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48
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Welsh DG, Tran CHT, Hald BO, Sancho M. The Conducted Vasomotor Response: Function, Biophysical Basis, and Pharmacological Control. Annu Rev Pharmacol Toxicol 2017; 58:391-410. [PMID: 28968190 DOI: 10.1146/annurev-pharmtox-010617-052623] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Arterial tone is coordinated among vessel segments to optimize nutrient transport and organ function. Coordinated vasomotor activity is remarkable to observe and depends on stimuli, sparsely generated in tissue, eliciting electrical responses that conduct lengthwise among electrically coupled vascular cells. The conducted response is the focus of this topical review, and in this regard, the authors highlight literature that advances an appreciation of functional significance, cellular mechanisms, and biophysical principles. Of particular note, this review stresses that conduction is enabled by a defined pattern of charge movement along the arterial wall as set by three key parameters (tissue structure, gap junctional resistivity, and ion channel activity). The impact of disease on conduction is carefully discussed, as are potential strategies to restore this key biological response and, along with it, the match of blood flow delivery with tissue energetic demand.
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Affiliation(s)
- Donald G Welsh
- Robarts Research Institute, Department of Physiology and Pharmacology, Schulich School of Medicine, University of Western Ontario, London, Ontario N6A 5B7, Canada;
| | - Cam Ha T Tran
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Bjorn O Hald
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Maria Sancho
- Robarts Research Institute, Department of Physiology and Pharmacology, Schulich School of Medicine, University of Western Ontario, London, Ontario N6A 5B7, Canada;
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49
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Senbel AM, Abd Elmoneim HM, Sharabi FM, Mohy El-Din MM. Neuronal Voltage Gated Potassium Channels May Modulate Nitric Oxide Synthesis in Corpus Cavernosum. Front Pharmacol 2017; 8:297. [PMID: 28603495 PMCID: PMC5445172 DOI: 10.3389/fphar.2017.00297] [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: 12/18/2016] [Accepted: 05/10/2017] [Indexed: 11/24/2022] Open
Abstract
Potassium channels (K+Ch) in corpus cavernosum play an important role in the regulation of erection. Nitric oxide (NO) acts through opening of K+Ch leading to hyperpolarization and relaxation. Aim : This study aims to update knowledge about the role of voltage-gated K+Ch (KV) channels in erectile machinery and investigate their role in the control of NO action &/or synthesis in the corpus cavernosum. Methods : Tension studies using isolated rabbit corpus cavernosum (CC) strips and rat anococcygeus muscle were conducted. Results are expressed as mean ± SEM. Results : Electric field stimulation (EFS, 2–16 Hz) evoked frequency-dependent relaxations of the PE (phenylephrine)-precontracted CC strips. At 2 Hz, EFS-induced relaxation amounted to 73.17 ± 2.55% in presence 4-AP (10−3 M) compared to 41.98 ± 1.45% as control. None of the other selective K+Ch blockers tested inhibited EFS-induced relaxation. 4-AP (10−3M) significantly attenuated ACh-induced relaxation of rabbit CC where dose-response curve was clearly shifted upward, and attenuated SNP- induced relaxation, for example, to 49.28 ± 4.52% compared to 65.53 ± 3.01% as control at 10−6 M SNP. The potentiatory effect of 4-AP on EFS was abolished or reversed in presence of NG-nitro-L-arginine (L-NNA, non-selective nitric oxide synthase inhibitor, 10−5M, and 2 × 10−4M). Same results were observed in rat anococcygeus muscle which is a part of the erectile machinery in rats. Conclusion : This study provides evidence for the presence of prejunctional voltage-gated K+Ch in CC, the blockade of which may increase the neuronal synthesis of NO.
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Affiliation(s)
- Amira M Senbel
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria UniversityAlexandria, Egypt
| | - Heba M Abd Elmoneim
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria UniversityAlexandria, Egypt
| | - Fouad M Sharabi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria UniversityAlexandria, Egypt
| | - Mahmoud M Mohy El-Din
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria UniversityAlexandria, Egypt
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50
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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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