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Zhuang W, Mun SY, Park M, Jeong J, Kim HR, Park H, Han ET, Han JH, Chun W, Li H, Park WS. Second-generation antipsychotic quetiapine blocks voltage-dependent potassium channels in coronary arterial smooth muscle cells. J Appl Toxicol 2024; 44:1446-1453. [PMID: 38797990 DOI: 10.1002/jat.4648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 05/06/2024] [Accepted: 05/13/2024] [Indexed: 05/29/2024]
Abstract
Voltage-dependent K+ (Kv) channels play an important role in restoring the membrane potential to its resting state, thereby maintaining vascular tone. In this study, native smooth muscle cells from rabbit coronary arteries were used to investigate the inhibitory effect of quetiapine, an atypical antipsychotic agent, on Kv channels. Quetiapine showed a concentration-dependent inhibition of Kv channels, with an IC50 of 47.98 ± 9.46 μM. Although quetiapine (50 μM) did not alter the steady-state activation curve, it caused a negative shift in the steady-state inactivation curve. The application of 1 and 2 Hz train steps in the presence of quetiapine significantly increased the inhibition of Kv current. Moreover, the recovery time constants from inactivation were prolonged in the presence of quetiapine, suggesting that its inhibitory action on Kv channels is use (state)-dependent. The inhibitory effects of quetiapine were not significantly affected by pretreatment with Kv1.5, Kv2.1, and Kv7 subtype inhibitors. Based on these findings, we conclude that quetiapine inhibits Kv channels in both a concentration- and use (state)-dependent manner. Given the physiological significance of Kv channels, caution is advised in the use of quetiapine as an antipsychotic due to its potential side effects on cardiovascular Kv channels.
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MESH Headings
- Quetiapine Fumarate/pharmacology
- Animals
- Rabbits
- Antipsychotic Agents/pharmacology
- Antipsychotic Agents/toxicity
- Potassium Channels, Voltage-Gated/drug effects
- Potassium Channels, Voltage-Gated/antagonists & inhibitors
- Potassium Channels, Voltage-Gated/metabolism
- Coronary Vessels/drug effects
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Potassium Channel Blockers/pharmacology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Male
- Dose-Response Relationship, Drug
- Membrane Potentials/drug effects
- Cells, Cultured
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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
| | - Hongzoo Park
- Institute of Medical Sciences, Department of Urology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Eun-Taek Han
- Department of Medical Environmental Biology and Tropical Medicine, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Jin-Hee Han
- Department of Medical Environmental Biology and Tropical Medicine, Kangwon National University School of Medicine, Chuncheon, South Korea
| | - Wanjoo Chun
- Department of Pharmacology, Kangwon National University School of Medicine, Chuncheon, 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, Jiangsu, China
| | - 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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Piragine E, Citi V, Lawson K, Calderone V, Martelli A. Regulation of blood pressure by natural sulfur compounds: Focus on their mechanisms of action. Biochem Pharmacol 2022; 206:115302. [PMID: 36265595 DOI: 10.1016/j.bcp.2022.115302] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 12/14/2022]
Abstract
Natural sulfur compounds are emerging as therapeutic options for the management of hypertension and prehypertension. They are mainly represented by polysulfides from Alliaceae (i.e., garlic) and isothiocyanates from Brassicaceae (or crucifers). The beneficial cardiovascular effects of these compounds, especially garlic polysulfides, are well known and widely reported both in preclinical and clinical studies. However, only a few authors have linked the ability of natural sulfur compounds to induce vasorelaxation and subsequent antihypertensive effects with their ability to release hydrogen sulfide (H2S) in biological tissue. H2S is an endogenous gasotransmitter involved in vascular tone regulation. Some cardiovascular diseases, such as hypertension, are associated with lower plasma H2S levels. Consequently, exogenous sources of H2S (H2S donors) have been designed and synthesized or identified among secondary plant metabolites as potential therapeutic options. In addition to antioxidant effects due to its chemical properties as a reducing agent, H2S induces vasorelaxation by interacting with a range of molecular targets. The mechanisms of action accounting for H2S-induced vasodilation include opening of vascular potassium channels (such as ATP-sensitive (KATP) and voltage-operated (Kv7) channels), inhibition of 5-phosphodiesterase (5-PDE), and activation of vascular endothelial growth factor receptor-2 (VEGFR-2). These effects may be attributed to H2S-induced S-persulfidation (or S-sulfhydration), which is a posttranslational modification of cysteine residues of many types of proteins resulting in structural and functional alterations (activation/inhibition). Thus, H2S donors, such as natural sulfur compounds, are promising antihypertensive agents with novel mechanisms of action.
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Affiliation(s)
- Eugenia Piragine
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Valentina Citi
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy
| | - Kim Lawson
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield S1 1WB, UK
| | - Vincenzo Calderone
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; Interdepartmental Research Center "Nutrafood: Nutraceutica e Alimentazione per la Salute", University of Pisa, 56126 Pisa, Italy; Interdepartmental Research Center "Biology and Pathology of Ageing", University of Pisa, 56126 Pisa, Italy
| | - Alma Martelli
- Department of Pharmacy, University of Pisa, Via Bonanno 6, 56126 Pisa, Italy; Interdepartmental Research Center "Nutrafood: Nutraceutica e Alimentazione per la Salute", University of Pisa, 56126 Pisa, Italy; Interdepartmental Research Center "Biology and Pathology of Ageing", University of Pisa, 56126 Pisa, Italy.
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Ross RL, Mavria G, Del Galdo F, Elies J. Downregulation of Vascular Hemeoxygenase-1 Leads to Vasculopathy in Systemic Sclerosis. Front Physiol 2022; 13:900631. [PMID: 35600300 PMCID: PMC9117635 DOI: 10.3389/fphys.2022.900631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 04/12/2022] [Indexed: 11/13/2022] Open
Abstract
Systemic sclerosis (SSc) is a terminal disease characterized by vasculopathy, tissue fibrosis, and autoimmunity. Although the exact etiology of SSc remains unknown, endothelial dysfunction, oxidative stress, and calcium handling dysregulation have been associated with a large number of SSc-related complications such as neointima formation, vasculogenesis, pulmonary arterial hypertension, impaired angiogenesis, and cardiac arrhythmias. Hemeoxygenase-1 (HO-1) is an antioxidant enzyme involved in multiple biological actions in the cardiovascular system including vascular tone, angiogenesis, cellular proliferation, apoptosis, and oxidative stress. The aim of this work was to investigate the physiological role of HO-1 and its relevance in the cardiovascular complications occurring in SSc. We found that, in early phases of SSc, the expression of HO-1 in dermal fibroblast is lower compared to those isolated from healthy control individuals. This is particularly relevant as reduction of the HO-1/CO signaling pathway is associated with endothelial dysfunction and vasculopathy. We show evidence of the role of HO-1/carbon monoxide (CO) signaling pathway in calcium handling. Using an in vitro model of pulmonary arterial hypertension (PAH) we investigated the role of HO-1 in Ca2+ mobilization from intracellular stores. Our results indicate that HO-1 regulates calcium release from intracellular stores of human pulmonary arterial endothelial cells. We interrogated the activity of HO-1 in angiogenesis using an organotypic co-culture of fibroblast-endothelial cell. Inhibition of HO-1 significantly reduced the ability of endothelial cells to form tubules. We further investigated if this could be associated with cell motility or migration of endothelial cells into the extracellular matrix synthesized by fibroblasts. By mean of holographic imaging, we studied the morphological and functional features of endothelial cells in the presence of an HO-1 activator and selective inhibitors. Our results demonstrate that inhibition of HO-1 significantly reduces cell proliferation and cell motility (migration) of cultured endothelial cells, whilst activation of HO-1 does not modify either morphology, proliferation or motility. In addition, we investigated the actions of CO on the Kv7.1 (KCQN1) channel current, an important component of the cardiac action potential repolarization. Using electrophysiology (whole-cell patch-clamp in a recombinant system overexpressing the KCQN1 channel), we assessed the regulation of KCQN1 by CO. CORM-2, a CO donor, significantly reduced the Kv7.1 current, suggesting that HO-1/CO signaling may play a role in the modulation of the cardiac action potential via regulation of this ion channel. In summary, our results indicate a clear link between: 1) downregulation of HO-1/CO signaling; and 2) pathophysiological processes occurring in early phases of SSc, such as calcium homeostasis dysregulation, impaired angiogenesis and cardiac arrhythmias. A better understanding of the canonical actions (mainly due to the biological actions of CO), and non-canonical actions of HO-1, as well as the interaction of HO-1/CO signaling with other gasotransmitters in SSc will contribute to the development of novel therapeutic approaches.
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Affiliation(s)
- Rebecca L Ross
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
- Scleroderma Programme, NIHR Leeds Musculoskeletal Biomedical Research Centre, Leeds, United Kingdom
| | - Georgia Mavria
- Signal Transduction and Tumour Microenvironment Group, Leeds Institute of Cancer and Pathology, University of Leeds, Leeds, United Kingdom
| | - Francesco Del Galdo
- Leeds Institute of Rheumatic and Musculoskeletal Medicine, Faculty of Medicine and Health, University of Leeds, Leeds, United Kingdom
- Scleroderma Programme, NIHR Leeds Musculoskeletal Biomedical Research Centre, Leeds, United Kingdom
| | - Jacobo Elies
- Cardiovascular Research Group, Faculty of Life Sciences, University of Bradford, Bradford, United Kingdom
- *Correspondence: Jacobo Elies,
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Peixoto-Neves D, Kanthakumar P, Afolabi JM, Soni H, Buddington RK, Adebiyi A. K V7.1 channel blockade inhibits neonatal renal autoregulation triggered by a step decrease in arterial pressure. Am J Physiol Renal Physiol 2022; 322:F197-F207. [PMID: 35001664 PMCID: PMC8816635 DOI: 10.1152/ajprenal.00568.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
KV7 channels, the voltage-gated K+ channels encoded by KCNQ genes, mediate heterogeneous vascular responses in rodents. Postnatal changes in the functional expression of KV7 channels have been reported in rodent saphenous arteries, but their physiological function in the neonatal renal vascular bed is unclear. Here, we report that, unlike adult pigs, only KCNQ1 (KV7.1) out of the five members of KCNQ genes was detected in neonatal pig renal microvessels. KCNQ1 is present in fetal pig kidneys as early as day 50 of gestation, and the level of expression remains the same up to postnatal day 21. Activation of renal vascular smooth muscle cell (SMC) KV7.1 stimulated whole cell currents, inhibited by HMR1556 (HMR), a selective KV7.1 blocker. HMR did not change the steady-state diameter of isolated renal microvessels. Similarly, intrarenal artery infusion of HMR did not alter mean arterial pressure, renal blood flow, and renal vascular resistance in the pigs. An ∼20 mmHg reduction in mean arterial pressure evoked effective autoregulation of renal blood flow, which HMR inhibited. We conclude that 1) the expression of KCNQ isoforms in porcine renal microvessels is dependent on kidney maturation, 2) KV7.1 is functionally expressed in neonatal pig renal vascular SMCs, 3) a decrease in arterial pressure up to 20 mmHg induces renal autoregulation in neonatal pigs, and 4) SMC KV7.1 does not control basal renal vascular tone but contributes to neonatal renal autoregulation triggered by a step decrease in arterial pressure.NEW & NOTEWORTHY KV7.1 is present in fetal pig kidneys as early as day 50 of gestation, and the level of expression remains the same up to postnatal day 21. KV7.1 is functionally expressed in neonatal pig renal vascular smooth muscle cells (SMCs). A decrease in arterial pressure up to 20 mmHg induces renal autoregulation in neonatal pigs. Although SMC KV7.1 does not control basal renal vascular resistance, its inhibition blunts neonatal renal autoregulation engendered by a step decrease in arterial pressure.
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Affiliation(s)
- Dieniffer Peixoto-Neves
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Jeremiah M. Afolabi
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Hitesh Soni
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Adebowale Adebiyi
- 1Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee
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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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Vasopressin-stimulated ORAI1 expression and store-operated Ca 2+ entry in aortic smooth muscle cells. J Mol Med (Berl) 2021; 99:373-382. [PMID: 33409552 DOI: 10.1007/s00109-020-02016-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/04/2020] [Accepted: 11/23/2020] [Indexed: 10/22/2022]
Abstract
Vascular calcification may result from stimulation of osteogenic signalling with upregulation of the transcription factors CBFA1, MSX2 and SOX9, as well as alkaline phosphatase (ALPL), which degrades and thus inactivates the calcification inhibitor pyrophosphate. Osteogenic signalling further involves upregulation of the Ca2+-channel ORAI1. The channel is activated by STIM1 and then accomplishes store-operated Ca2+ entry. ORAI1 and STIM1 are upregulated by the serum & glucocorticoid inducible kinase 1 (SGK1) which is critically important for osteogenic signalling. Stimulators of vascular calcification include vasopressin. The present study explored whether exposure of human aortic smooth muscle cells (HAoSMCs) to vasopressin upregulates ORAI1 and/or STIM1 expression, store-operated Ca2+ entry and osteogenic signalling. To this end, HAoSMCs were exposed to vasopressin (100 nM, 24 h) without or with additional exposure to ORAI1 blocker MRS1845 (10 μM) or SGK1 inhibitor GSK-650394 (1 μM). Transcript levels were measured using q-RT-PCR, cytosolic Ca2+-concentration ([Ca2+]i) by Fura-2-fluorescence, and store-operated Ca2+ entry from increase of [Ca2+]i following re-addition of extracellular Ca2+ after store depletion with thapsigargin (1 μM). As a result, vasopressin enhanced the transcript levels of ORAI1 and STIM1, store-operated Ca2+ entry, as well as the transcript levels of CBFA1, MSX2, SOX9 and ALPL. The effect of vasopressin on store-operated Ca2+ entry as well as on transcript levels of CBFA1, MSX2, SOX9 and ALPL was virtually abrogated by MRS1845 and GSK-650394. In conclusion, vasopressin stimulates expression of ORAI1/STIM1, thus augmenting store-operated Ca2+ entry and osteogenic signalling. In HAoSMCs, vasopressin (VP) upregulates Ca2+ channel ORAI1 and its activator STIM1. VP upregulates store-operated Ca2+ entry (SOCE) and osteogenic signalling (OS). VP-induced SOCE, OS and Ca2+-deposition are disrupted by ORAI1 inhibitor MRS1845. VP-induced SOCE, OS and Ca2+-deposition are disrupted by SGK1 blocker GSK-650394. KEY MESSAGES: • In HAoSMCs, vasopressin (VP) upregulates Ca2+ channel ORAI1 and its activator STIM1. • VP upregulates store-operated Ca2+ entry (SOCE) and osteogenic signalling (OS). • VP-induced SOCE, OS and Ca2+-deposition are disrupted by ORAI1 inhibitor MRS1845. • VP-induced SOCE, OS and Ca2+-deposition are disrupted by SGK1 blocker GSK-650394.
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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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