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Zhu W, Gu Q, Liu B, Si Y, Sun H, Zhong J, Lu Y, Wang D, Xue J, Qin S. Accurate in vivo real-time determination of the hydrogen concentration in different tissues of mice after hydrogen inhalation. Heliyon 2022; 8:e10778. [PMID: 36203896 PMCID: PMC9530838 DOI: 10.1016/j.heliyon.2022.e10778] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 05/11/2022] [Accepted: 09/22/2022] [Indexed: 11/24/2022] Open
Abstract
As an antioxidant, anti-inflammatory and anti-apoptotic agent, hydrogen (H2) shows a promising potential in basic and clinical research against various diseases owing to its safety and efficacy. However, knowledge involving its underlying mechanisms of action, dosage effects, and dose duration remains limited. Previously, the dynamics of H2 concentrations in different tissues of rats after exogenous H2 inhalation had been detected by our team. Here, sequential changes of H2 concentrations in different tissues of another most commonly used experimental rodent mice were monitored in real time with an electrochemical H2 gas sensor during continuous different concentrations of H2 inhalation targeting on five tissues including brain, liver, spleen, kidney, and gastrocnemius. The results showed that the H2 saturation concentrations varied among tissues significantly regardless of the concentration of H2 inhaled, and they were detected the highest in the kidney but the lowest in the gastrocnemius. Meantime, it required a significant longer time to saturate in the thigh muscle. By comparing the H2 saturation concentrations of mice and rats, we found that there were no differences detected in most tissues except the kidney and spleen. Both gas diffusion and bloodstream transport could help the H2 reach to most organs. The results provide data reference for dosage selection, dose duration determination to ensure optimal therapeutic effects of H2 for mice experiments.
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Ottolini M, Sonkusare SK. The Calcium Signaling Mechanisms in Arterial Smooth Muscle and Endothelial Cells. Compr Physiol 2021; 11:1831-1869. [PMID: 33792900 PMCID: PMC10388069 DOI: 10.1002/cphy.c200030] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The contractile state of resistance arteries and arterioles is a crucial determinant of blood pressure and blood flow. Physiological regulation of arterial contractility requires constant communication between endothelial and smooth muscle cells. Various Ca2+ signals and Ca2+ -sensitive targets ensure dynamic control of intercellular communications in the vascular wall. The functional effect of a Ca2+ signal on arterial contractility depends on the type of Ca2+ -sensitive target engaged by that signal. Recent studies using advanced imaging methods have identified the spatiotemporal signatures of individual Ca2+ signals that control arterial and arteriolar contractility. Broadly speaking, intracellular Ca2+ is increased by ion channels and transporters on the plasma membrane and endoplasmic reticular membrane. Physiological roles for many vascular Ca2+ signals have already been confirmed, while further investigation is needed for other Ca2+ signals. This article focuses on endothelial and smooth muscle Ca2+ signaling mechanisms in resistance arteries and arterioles. We discuss the Ca2+ entry pathways at the plasma membrane, Ca2+ release signals from the intracellular stores, the functional and physiological relevance of Ca2+ signals, and their regulatory mechanisms. Finally, we describe the contribution of abnormal endothelial and smooth muscle Ca2+ signals to the pathogenesis of vascular disorders. © 2021 American Physiological Society. Compr Physiol 11:1831-1869, 2021.
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Affiliation(s)
- Matteo Ottolini
- Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA
| | - Swapnil K Sonkusare
- Department of Pharmacology, University of Virginia, Charlottesville, Virginia, USA.,Department of Molecular Physiology & Biological Physics, University of Virginia, Charlottesville, Virginia, USA.,Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia, USA
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Ottolini M, Hong K, Sonkusare SK. Calcium signals that determine vascular resistance. WILEY INTERDISCIPLINARY REVIEWS. SYSTEMS BIOLOGY AND MEDICINE 2019; 11:e1448. [PMID: 30884210 PMCID: PMC6688910 DOI: 10.1002/wsbm.1448] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 02/07/2019] [Accepted: 02/14/2019] [Indexed: 12/19/2022]
Abstract
Small arteries in the body control vascular resistance, and therefore, blood pressure and blood flow. Endothelial and smooth muscle cells in the arterial walls respond to various stimuli by altering the vascular resistance on a moment to moment basis. Smooth muscle cells can directly influence arterial diameter by contracting or relaxing, whereas endothelial cells that line the inner walls of the arteries modulate the contractile state of surrounding smooth muscle cells. Cytosolic calcium is a key driver of endothelial and smooth muscle cell functions. Cytosolic calcium can be increased either by calcium release from intracellular stores through IP3 or ryanodine receptors, or the influx of extracellular calcium through ion channels at the cell membrane. Depending on the cell type, spatial localization, source of a calcium signal, and the calcium-sensitive target activated, a particular calcium signal can dilate or constrict the arteries. Calcium signals in the vasculature can be classified into several types based on their source, kinetics, and spatial and temporal properties. The calcium signaling mechanisms in smooth muscle and endothelial cells have been extensively studied in the native or freshly isolated cells, therefore, this review is limited to the discussions of studies in native or freshly isolated cells. This article is categorized under: Biological Mechanisms > Cell Signaling Laboratory Methods and Technologies > Imaging Models of Systems Properties and Processes > Mechanistic Models.
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Affiliation(s)
- Matteo Ottolini
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Pharmacology, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
| | - Kwangseok Hong
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Physical Education, Chung-Ang University, Seoul, 06974, South Korea
| | - Swapnil K. Sonkusare
- Robert M. Berne Cardiovascular Research Center, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Pharmacology, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia-School of Medicine, Charlottesville, VA, 22908, USA
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4
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Franco M, Pérez-Méndez O, Kulthinee S, Navar LG. Integration of purinergic and angiotensin II receptor function in renal vascular responses and renal injury in angiotensin II-dependent hypertension. Purinergic Signal 2019; 15:277-285. [PMID: 31183668 PMCID: PMC6635571 DOI: 10.1007/s11302-019-09662-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 05/30/2019] [Indexed: 12/24/2022] Open
Abstract
Glomerular arteriolar vasoconstriction and tubulointerstitial injury are observed before glomerular damage occurs in models of hypertension. High interstitial ATP concentrations, caused by the increase in arterial pressure, alter renal mechanisms involved in the long-term control of blood pressure, autoregulation of glomerular filtration rate and blood flow, tubuloglomerular feedback (TGF) responses, and sodium excretion. Elevated ATP concentrations and augmented expression of P2X receptors have been demonstrated under a genetic background or induction of hypertension with vasoconstrictor peptides. In addition to the alterations of the microcirculation in the hypertensive kidney, the vascular actions of elevated intrarenal angiotensin II levels may be mitigated by the administration of broad purinergic P2 antagonists or specific P2Y12, P2X1, and P2X7 receptor antagonists. Furthermore, the prevention of tubulointerstitial infiltration with immunosuppressor compounds reduces the development of salt-sensitive hypertension, indicating that tubulointerstitial inflammation is essential for the development and maintenance of hypertension. Inflammatory cells also express abundant purinergic receptors, and their activation by ATP induces cytokine and growth factor release that in turn contributes to augment tubulointerstitial inflammation. Collectively, the evidence suggests a pathophysiological activation of purinergic P2 receptors in angiotensin-dependent hypertension. Coexistent increases in intrarenal angiotensin II and activates Ang II AT1 receptors, which interacts with over-activated purinergic receptors in a complex manner, suggesting convergence of their post-receptor signaling processes.
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Affiliation(s)
- Martha Franco
- Department of Nephrology, Renal Pathophysiology Laboratory, Instituto Nacional de Cardiología “Ignacio Chávez”, Juan Badiano No.1, 14080 Mexico City, DF Mexico
| | - Oscar Pérez-Méndez
- Department Molecular Biology, Instituto Nacional de Cardiología “Ignacio Chávez”, Mexico City, Mexico
| | - Supaporn Kulthinee
- Department of Physiology and Hypertension and Renal Center, Tulane University School of Medicine, New Orleans, LA USA
- Department of Cardiovascular and Thoracic Technology, Chulabhorn International College of Medicine, Thammasat University, Rangsit, Pathum Thani Thailand
| | - L. Gabriel Navar
- Department of Physiology and Hypertension and Renal Center, Tulane University School of Medicine, New Orleans, LA USA
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5
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Jackson WF, Boerman EM. Voltage-gated Ca 2+ channel activity modulates smooth muscle cell calcium waves in hamster cremaster arterioles. Am J Physiol Heart Circ Physiol 2018; 315:H871-H878. [PMID: 29957015 DOI: 10.1152/ajpheart.00292.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cremaster muscle arteriolar smooth muscle cells (SMCs) display inositol 1,4,5-trisphosphate receptor-dependent Ca2+ waves that contribute to global myoplasmic Ca2+ concentration and myogenic tone. However, the contribution made by voltage-gated Ca2+ channels (VGCCs) to arteriolar SMC Ca2+ waves is unknown. We tested the hypothesis that VGCC activity modulates SMC Ca2+ waves in pressurized (80 cmH2O/59 mmHg, 34°C) hamster cremaster muscle arterioles loaded with Fluo-4 and imaged by confocal microscopy. Removal of extracellular Ca2+ dilated arterioles (32 ± 3 to 45 ± 3 μm, n = 15, P < 0.05) and inhibited the occurrence, amplitude, and frequency of Ca2+ waves ( n = 15, P < 0.05), indicating dependence of Ca2+ waves on Ca2+ influx. Blockade of VGCCs with nifedipine (1 μM) or diltiazem (10 μM) or deactivation of VGCCs by hyperpolarization of smooth muscle with the K+ channel agonist cromakalim (10 μM) produced similar inhibition of Ca2+ waves ( P < 0.05). Conversely, depolarization of SMCs with the K+ channel blocker tetraethylammonium (1 mM) constricted arterioles from 26 ± 3 to 14 ± 2 μm ( n = 11, P < 0.05) and increased wave occurrence (9 ± 3 to 16 ± 3 waves/SMC), amplitude (1.6 ± 0.07 to 1.9 ± 0.1), and frequency (0.5 ± 0.1 to 0.9 ± 0.2 Hz, n = 10, P < 0.05), effects that were blocked by nifedipine (1 μM, P < 0.05). Similarly, the VGCC agonist Bay K8644 (5 nM) constricted arterioles from 14 ± 1 to 8 ± 1 μm and increased wave occurrence (3 ± 1 to 10 ± 1 waves/SMC) and frequency (0.2 ± 0.1 to 0.6 ± 0.1 Hz, n = 6, P < 0.05), effects that were unaltered by ryanodine (50 μM, n = 6, P > 0.05). These data support the hypothesis that Ca2+ waves in arteriolar SMCs depend, in part, on the activity of VGCCs. NEW & NOTEWORTHY Arterioles that control blood flow to and within skeletal muscle depend on Ca2+ influx through voltage-gated Ca2+ channels and release of Ca2+ from internal stores through inositol 1,4,5-trisphosphate receptors in the form of Ca2+ waves to maintain pressure-induced smooth muscle tone.
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Affiliation(s)
- William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University , East Lansing, Michigan
| | - Erika M Boerman
- Department of Pharmacology and Toxicology, Michigan State University , East Lansing, Michigan
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6
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Varghese JF, Patel R, Yadav UCS. Novel Insights in the Metabolic Syndrome-induced Oxidative Stress and Inflammation-mediated Atherosclerosis. Curr Cardiol Rev 2018; 14:4-14. [PMID: 28990536 PMCID: PMC5872260 DOI: 10.2174/1573403x13666171009112250] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/09/2017] [Accepted: 09/28/2017] [Indexed: 02/06/2023] Open
Abstract
Context: Atherosclerosis is a progressive pathological process and a leading cause of mor-tality worldwide. Clinical research and epidemiological studies state that atherosclerosis is caused by an amalgamation of metabolic and inflammatory deregulation involving three important pathological events including Endothelial Dysfunction (ED), Foam Cell Formation (FCF), and Vascular Smooth Muscle Cells (VSMCs) proliferation and migration. Objectives: Research in recent years has identified Metabolic Syndrome (MS), which involves factors such as obesity, insulin resistance, dyslipidemia and diabetes, to be responsible for the pathophysiol-ogy of atherosclerosis. These factors elevate oxidative stress and inflammation-induced key signalling molecules and various microRNAs (miRs). In present study, we have reviewed recently identified molecular targets in the pathophysiology of atherosclerosis. Methods: Scientific literature obtained from databases such as university library, PubMed and Google along with evidences from published experimental work in relevant journals has been sum-marized in this review article. Results: The molecular events and cell signalling implicated in atherogenic processes of ED, FCF and VSMCs hyperplasia are sequential and progressive, and involve cross talks at many levels. Specific molecules such as transcription factors, inflammatory cytokines and chemokines and miRs have been identified playing crucial role in most of the events leading to atherosclerosis. Conclusion: Studies associated with MS induced oxidative stress- and inflammation- mediated sig-nalling pathways along with critical miRs help in better understanding of the pathophysiology of ath-erosclerosis. Several key molecules discussed in this review could be potent target for the prevention and treatment of atherosclerosis.
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Affiliation(s)
- Johnna F Varghese
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat - 382030, India
| | - Rohit Patel
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat - 382030, India
| | - Umesh C S Yadav
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat - 382030, India
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7
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Bidaux G, Gordienko D, Shapovalov G, Farfariello V, Borowiec AS, Iamshanova O, Lemonnier L, Gueguinou M, Guibon R, Fromont G, Paillard M, Gouriou Y, Chouabe C, Dewailly E, Gkika D, López-Alvarado P, Carlos Menéndez J, Héliot L, Slomianny C, Prevarskaya N. 4TM-TRPM8 channels are new gatekeepers of the ER-mitochondria Ca 2+ transfer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:981-994. [PMID: 29678654 DOI: 10.1016/j.bbamcr.2018.04.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 03/19/2018] [Accepted: 04/16/2018] [Indexed: 10/17/2022]
Abstract
Calcium (Ca2+) release from the endoplasmic reticulum plays an important role in many cell-fate defining cellular processes. Traditionally, this Ca2+ release was associated with the ER Ca2+ release channels, inositol 1,4,5‑triphosphate receptor (IP3R) and ryanodine receptor (RyR). Lately, however, other calcium conductances have been found to be intracellularly localized and to participate in cell fate regulation. Nonetheless, molecular identity and functional properties of the ER Ca2+ release mechanisms associated with multiple diseases, e.g. prostate cancer, remain unknown. Here we identify a new family of transient receptor potential melastatine 8 (TRPM8) channel isoforms as functional ER Ca2+ release channels expressed in mitochondria-associated ER membranes (MAMs). These TRPM8 isoforms exhibit an unconventional structure with 4 transmembrane domains (TMs) instead of 6 TMs characteristic of the TRP channel archetype. We show that these 4TM-TRPM8 isoforms form functional channels in the ER and participate in regulation of the steady-state Ca2+ concentration ([Ca2+]) in mitochondria and the ER. Thus, our study identifies 4TM-TRPM8 isoforms as ER Ca2+ release mechanism distinct from classical Ca2+ release channels.
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Affiliation(s)
- Gabriel Bidaux
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France; Laboratoire de Physique des Lasers, Atomes et Molécules, Equipe Biophotonique Cellulaire Fonctionnelle, UMR 8523, Parc scientifique de la Haute Borne, Villeneuve d'Ascq, France; Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69550 Bron, France; Hospices Civils de Lyon, Groupement Hospitalier EST, Département de Cardiologie, IHU-OPERA Bâtiment B13, 69550 Bron, France.
| | - Dmitri Gordienko
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France; Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - George Shapovalov
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Valerio Farfariello
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Anne-Sophie Borowiec
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Oksana Iamshanova
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Loic Lemonnier
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | | | - Roseline Guibon
- Inserm, UMR 1069, Université François Rabelais Tours, Tours, France
| | - Gaelle Fromont
- Inserm, UMR 1069, Université François Rabelais Tours, Tours, France
| | - Mélanie Paillard
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69550 Bron, France; Hospices Civils de Lyon, Groupement Hospitalier EST, Département de Cardiologie, IHU-OPERA Bâtiment B13, 69550 Bron, France
| | - Yves Gouriou
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69550 Bron, France; Hospices Civils de Lyon, Groupement Hospitalier EST, Département de Cardiologie, IHU-OPERA Bâtiment B13, 69550 Bron, France
| | - Christophe Chouabe
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69550 Bron, France; Hospices Civils de Lyon, Groupement Hospitalier EST, Département de Cardiologie, IHU-OPERA Bâtiment B13, 69550 Bron, France
| | - Etienne Dewailly
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Dimitra Gkika
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Pilar López-Alvarado
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain
| | - J Carlos Menéndez
- Unidad de Química Orgánica y Farmacéutica, Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense, 28040 Madrid, Spain
| | - Laurent Héliot
- Laboratoire de Physique des Lasers, Atomes et Molécules, Equipe Biophotonique Cellulaire Fonctionnelle, UMR 8523, Parc scientifique de la Haute Borne, Villeneuve d'Ascq, France
| | - Christian Slomianny
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France
| | - Natalia Prevarskaya
- Univ Lille, Inserm U1003, PHYCEL Laboratory, Physiologie Cellulaire, F-59000 Lille, France.
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8
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Park IK, Kim JH, Park CG, Kim MY, Parajuli SP, Hong CS, Choi S, Jun JY. Effects of ATP on Pacemaker Activity of Interstitial Cells of Cajal from the Mouse Small Intestine. Chonnam Med J 2018; 54:63-71. [PMID: 29399568 PMCID: PMC5794481 DOI: 10.4068/cmj.2018.54.1.63] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 10/23/2017] [Accepted: 10/25/2017] [Indexed: 01/23/2023] Open
Abstract
Purinergic receptors play an important role in regulating gastrointestinal (GI) motility. Interstitial cells of Cajal (ICCs) are pacemaker cells that regulate GI smooth muscle activity. We studied the functional roles of external adenosine 5′-triphosphate (ATP) on pacemaker activity in cultured ICCs from mouse small intestines by using the whole-cell patch clamp technique and intracellular Ca2+ ([Ca2+]i) imaging. External ATP dose-dependently depolarized the resting membrane and produced tonic inward pacemaker currents, and these effects were antagonized by suramin, a purinergic P2 receptor antagonist. ATP-induced effects on pacemaker currents were suppressed by an external Na+-free solution and inhibited by the nonselective cation channel blockers, flufenamic acid and niflumic acid. The removal of external Ca2+ or treatment with thapsigargin (inhibitor of Ca2+ uptake into endoplasmic reticulum) inhibited the ATP-induced effects on pacemaker currents. Spontaneous [Ca2+]i oscillations were enhanced by external ATP. These results suggest that external ATP modulates pacemaker activity by activating nonselective cation channels via external Ca2+ influx and [Ca2+]i release from the endoplasmic reticulum. Thus, it seems that activating the purinergic P2 receptor may modulate GI motility by acting on ICCs in the small intestine.
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Affiliation(s)
- Il Koo Park
- Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Jin Ho Kim
- Department of Neurology, College of Medicine, Chosun University, Gwangju, Korea
| | - Chan Guk Park
- Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Man Yoo Kim
- Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | | | - Chan Sik Hong
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Seok Choi
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Jae Yeoul Jun
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
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9
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Characterisation of preproendothelin-1 derived peptides identifies Endothelin-Like Domain Peptide as a modulator of Endothelin-1. Sci Rep 2017; 7:4956. [PMID: 28694457 PMCID: PMC5503984 DOI: 10.1038/s41598-017-05365-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 05/26/2017] [Indexed: 02/06/2023] Open
Abstract
Endothelin-1 (ET-1) is involved in the pathogenesis of cardiac and renal diseases, and in the progression of tumour growth in cancer, but current diagnosis and treatment remain inadequate. Peptides derived from the 212 amino acid precursor preproendothelin-1 (ppET-1) may have utility as biomarkers, or cause biological effects that are unaffected by endothelin receptor antagonists. Here, we used specific immunoassays and LC-MS/MS to identify NT-proET-1 (ppET-1[18–50]), Endothelin-Like Domain Peptide (ELDP, ppET-1[93–166]) and CT-proET-1 (ppET-1[169–212]) in conditioned media from cultured endothelial cells. Synthesis of these peptides correlated with ET-1, and plasma ELDP and CT-proET-1 were elevated in patients with chronic heart failure. Clearance rates of NT-proET-1, ELDP and CT-proET-1 were determined after i.v. injection in anaesthetised rats. CT-proET-1 had the slowest systemic clearance, hence providing a biological basis for it being a better biomarker of ET-1 synthesis. ELDP contains the evolutionary conserved endothelin-like domain sequence, which potentially confers biological activity. On isolated arteries ELDP lacked direct vasoconstrictor effects. However, it enhanced ET-1 vasoconstriction and prolonged the increase in blood pressure in anaesthetised rats. ELDP may therefore contribute to disease pathogenesis by augmenting ET-1 responses.
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10
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Tykocki NR, Boerman EM, Jackson WF. Smooth Muscle Ion Channels and Regulation of Vascular Tone in Resistance Arteries and Arterioles. Compr Physiol 2017; 7:485-581. [PMID: 28333380 DOI: 10.1002/cphy.c160011] [Citation(s) in RCA: 212] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Vascular tone of resistance arteries and arterioles determines peripheral vascular resistance, contributing to the regulation of blood pressure and blood flow to, and within the body's tissues and organs. Ion channels in the plasma membrane and endoplasmic reticulum of vascular smooth muscle cells (SMCs) in these blood vessels importantly contribute to the regulation of intracellular Ca2+ concentration, the primary determinant of SMC contractile activity and vascular tone. Ion channels provide the main source of activator Ca2+ that determines vascular tone, and strongly contribute to setting and regulating membrane potential, which, in turn, regulates the open-state-probability of voltage gated Ca2+ channels (VGCCs), the primary source of Ca2+ in resistance artery and arteriolar SMCs. Ion channel function is also modulated by vasoconstrictors and vasodilators, contributing to all aspects of the regulation of vascular tone. This review will focus on the physiology of VGCCs, voltage-gated K+ (KV) channels, large-conductance Ca2+-activated K+ (BKCa) channels, strong-inward-rectifier K+ (KIR) channels, ATP-sensitive K+ (KATP) channels, ryanodine receptors (RyRs), inositol 1,4,5-trisphosphate receptors (IP3Rs), and a variety of transient receptor potential (TRP) channels that contribute to pressure-induced myogenic tone in resistance arteries and arterioles, the modulation of the function of these ion channels by vasoconstrictors and vasodilators, their role in the functional regulation of tissue blood flow and their dysfunction in diseases such as hypertension, obesity, and diabetes. © 2017 American Physiological Society. Compr Physiol 7:485-581, 2017.
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Affiliation(s)
- Nathan R Tykocki
- Department of Pharmacology, University of Vermont, Burlington, Vermont, USA
| | - Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA
| | - William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA
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11
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Bidaux G, Borowiec AS, Prevarskaya N, Gordienko D. Fine-tuning of eTRPM8 expression and activity conditions keratinocyte fate. Channels (Austin) 2016; 10:320-31. [PMID: 27014839 DOI: 10.1080/19336950.2016.1168551] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Recently, we reported the cloning and characterization of short isoform of the icilin-activated cold receptor TRPM8 channel in keratinocytes, dubbed eTRPM8. We demonstrated that eTRPM8 via fine tuning of the endoplasmic reticulum (ER) - mitochondria Ca(2+) shuttling regulates mitochondrial ATP and superoxide (O2(•-)) production and, thereby, mediates control of epidermal homeostasis by mild cold. Here, we provide additional information explaining why eTRPM8 suppression and TRPM8 stimulation both inhibit keratinocyte growth. We also demonstrate that stimulation of eTRPM8 with icilin may give rise to sustained oscillatory responses. Furthermore, we show that ATP-induced cytosolic and mitochondrial Ca(2+) responses are attenuated by eTRPM8 suppression. This suggests positive interplay between eTRPM8 and purinergic signaling pathways, what may serve to facilitate the ER-mitochondria Ca(2+) shuttling. Finally, we demonstrate that cold (25°C) induces eTRPM8-dependent superoxide-mediated necrosis of keratinocytes. Altogether, these results are in line with our model of eTRPM8-mediated cold-dependent balance between keratinocyte proliferation and differentiation.
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Affiliation(s)
- Gabriel Bidaux
- a Inserm U-1003, Equipe labellisée par la Ligue Nationale contre le cancer, Université des Sciences et Technologies de Lille (USTL), Villeneuve d'Ascq , Bron , France.,b Univ Lyon, CarMeN laboratory, Inserm UMR1060 , INRA UMR1397, Insa-Lyon, Bron , France.,c IHU OPERA, Hospices Civils de Lyon, Groupement Hospitalier EST , Bron , France
| | - Anne-Sophie Borowiec
- a Inserm U-1003, Equipe labellisée par la Ligue Nationale contre le cancer, Université des Sciences et Technologies de Lille (USTL), Villeneuve d'Ascq , Bron , France
| | - Natalia Prevarskaya
- a Inserm U-1003, Equipe labellisée par la Ligue Nationale contre le cancer, Université des Sciences et Technologies de Lille (USTL), Villeneuve d'Ascq , Bron , France
| | - Dmitri Gordienko
- a Inserm U-1003, Equipe labellisée par la Ligue Nationale contre le cancer, Université des Sciences et Technologies de Lille (USTL), Villeneuve d'Ascq , Bron , France.,d Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling; Bogomoletz Institute of Physiology , Kiev , Ukraine
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12
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Epidermal TRPM8 channel isoform controls the balance between keratinocyte proliferation and differentiation in a cold-dependent manner. Proc Natl Acad Sci U S A 2015; 112:E3345-54. [PMID: 26080404 DOI: 10.1073/pnas.1423357112] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Deviation of the ambient temperature is one of the most ubiquitous stimuli that continuously affect mammals' skin. Although the role of the warmth receptors in epidermal homeostasis (EH) was elucidated in recent years, the mystery of the keratinocyte mild-cold sensor remains unsolved. Here we report the cloning and characterization of a new functional epidermal isoform of the transient receptor potential M8 (TRPM8) mild-cold receptor, dubbed epidermal TRPM8 (eTRPM8), which is localized in the keratinocyte endoplasmic reticulum membrane and controls mitochondrial Ca(2+) concentration ([Ca(2+)]m). In turn, [Ca(2+)]m modulates ATP and superoxide (O2(·-)) synthesis in a cold-dependent manner. We report that this fine tuning of ATP and O2(·-) levels by cooling controls the balance between keratinocyte proliferation and differentiation. Finally, to ascertain eTRPM8's role in EH in vivo we developed a new functional knockout mouse strain by deleting the pore domain of TRPM8 and demonstrated that eTRPM8 knockout impairs adaptation of the epidermis to low temperatures.
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13
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Abstract
Intrarenal autoregulatory mechanisms maintain renal blood flow (RBF) and glomerular filtration rate (GFR) independent of renal perfusion pressure (RPP) over a defined range (80-180 mmHg). Such autoregulation is mediated largely by the myogenic and the macula densa-tubuloglomerular feedback (MD-TGF) responses that regulate preglomerular vasomotor tone primarily of the afferent arteriole. Differences in response times allow separation of these mechanisms in the time and frequency domains. Mechanotransduction initiating the myogenic response requires a sensing mechanism activated by stretch of vascular smooth muscle cells (VSMCs) and coupled to intracellular signaling pathways eliciting plasma membrane depolarization and a rise in cytosolic free calcium concentration ([Ca(2+)]i). Proposed mechanosensors include epithelial sodium channels (ENaC), integrins, and/or transient receptor potential (TRP) channels. Increased [Ca(2+)]i occurs predominantly by Ca(2+) influx through L-type voltage-operated Ca(2+) channels (VOCC). Increased [Ca(2+)]i activates inositol trisphosphate receptors (IP3R) and ryanodine receptors (RyR) to mobilize Ca(2+) from sarcoplasmic reticular stores. Myogenic vasoconstriction is sustained by increased Ca(2+) sensitivity, mediated by protein kinase C and Rho/Rho-kinase that favors a positive balance between myosin light-chain kinase and phosphatase. Increased RPP activates MD-TGF by transducing a signal of epithelial MD salt reabsorption to adjust afferent arteriolar vasoconstriction. A combination of vascular and tubular mechanisms, novel to the kidney, provides for high autoregulatory efficiency that maintains RBF and GFR, stabilizes sodium excretion, and buffers transmission of RPP to sensitive glomerular capillaries, thereby protecting against hypertensive barotrauma. A unique aspect of the myogenic response in the renal vasculature is modulation of its strength and speed by the MD-TGF and by a connecting tubule glomerular feedback (CT-GF) mechanism. Reactive oxygen species and nitric oxide are modulators of myogenic and MD-TGF mechanisms. Attenuated renal autoregulation contributes to renal damage in many, but not all, models of renal, diabetic, and hypertensive diseases. This review provides a summary of our current knowledge regarding underlying mechanisms enabling renal autoregulation in health and disease and methods used for its study.
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Affiliation(s)
- Mattias Carlström
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Christopher S Wilcox
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - William J Arendshorst
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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14
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Gkika D, Lemonnier L, Shapovalov G, Gordienko D, Poux C, Bernardini M, Bokhobza A, Bidaux G, Degerny C, Verreman K, Guarmit B, Benahmed M, de Launoit Y, Bindels RJM, Fiorio Pla A, Prevarskaya N. TRP channel-associated factors are a novel protein family that regulates TRPM8 trafficking and activity. ACTA ACUST UNITED AC 2015; 208:89-107. [PMID: 25559186 PMCID: PMC4284226 DOI: 10.1083/jcb.201402076] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
TCAF1 and TCAF2 bind to TRPM8 and promote its cell surface trafficking but differentially regulate its gating properties, leading to opposing effects on prostate cancer cell migration. TRPM8 is a cold sensor that is highly expressed in the prostate as well as in other non-temperature-sensing organs, and is regulated by downstream receptor–activated signaling pathways. However, little is known about the intracellular proteins necessary for channel function. Here, we identify two previously unknown proteins, which we have named “TRP channel–associated factors” (TCAFs), as new TRPM8 partner proteins, and we demonstrate that they are necessary for channel function. TCAF1 and TCAF2 both bind to the TRPM8 channel and promote its trafficking to the cell surface. However, they exert opposing effects on TRPM8 gating properties. Functional interaction of TCAF1/TRPM8 also leads to a reduction in both the speed and directionality of migration of prostate cancer cells, which is consistent with an observed loss of expression of TCAF1 in metastatic human specimens, whereas TCAF2 promotes migration. The identification of TCAFs introduces a novel mechanism for modulation of TRPM8 channel activity.
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Affiliation(s)
- Dimitra Gkika
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
| | - Loic Lemonnier
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
| | - George Shapovalov
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
| | - Dmitri Gordienko
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
| | - Céline Poux
- Centre national de la Recherche Scientifique (CNRS) UMR 8198 and Laboratoire de Génétique & Evolution des Populations Végétales (GEPV), Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
| | - Michela Bernardini
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France Department of Life Science and Systems Biology, University of Torino, 10123 Torino, Italy
| | - Alexandre Bokhobza
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
| | - Gabriel Bidaux
- Laboratoire Biophotonique Cellulaire Fonctionnelle, Institut de Recherche Interdisciplinaire, USR3078 Centre National de la Recherche Scientifique, Parc scientifique de la Haute Borne, Villeneuve d'Ascq, F-59655 France
| | - Cindy Degerny
- CNRS UMR 8161, Institut de Biologie de Lille, Université de Lille-Nord de France, Institut Pasteur de Lille, 59019 Lille Cedex, France
| | - Kathye Verreman
- CNRS UMR 8161, Institut de Biologie de Lille, Université de Lille-Nord de France, Institut Pasteur de Lille, 59019 Lille Cedex, France
| | - Basma Guarmit
- Inserm, Institut National de la Santé et de la Recherche Médicale U895, Centre Méditerranéen de Médecine Moléculaire, Hôpitall'Archet, 06204 Nice, France
| | - Mohamed Benahmed
- Inserm, Institut National de la Santé et de la Recherche Médicale U895, Centre Méditerranéen de Médecine Moléculaire, Hôpitall'Archet, 06204 Nice, France
| | - Yvan de Launoit
- CNRS UMR 8161, Institut de Biologie de Lille, Université de Lille-Nord de France, Institut Pasteur de Lille, 59019 Lille Cedex, France
| | - Rene J M Bindels
- Department of Physiology, Radboud University Nijmegen Medical Centre, 6500HB Nijmegen, Netherlands
| | - Alessandra Fiorio Pla
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France Department of Life Science and Systems Biology, University of Torino, 10123 Torino, Italy
| | - Natalia Prevarskaya
- Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille (USTL), 59655 Villeneuve d'Ascq Cedex, France
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15
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Sukhanova KY, Bouryi VA, Gordienko DV. Convergence of Ionotropic and Metabotropic Signal Pathways upon Activation of P2X Receptors in Vascular Smooth Muscle Cells. NEUROPHYSIOLOGY+ 2015. [DOI: 10.1007/s11062-015-9464-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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16
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Gordienko D, Povstyan O, Sukhanova K, Raphaël M, Harhun M, Dyskina Y, Lehen'kyi V, Jama A, Lu ZL, Skryma R, Prevarskaya N. Impaired P2X signalling pathways in renal microvascular myocytes in genetic hypertension. Cardiovasc Res 2014; 105:131-42. [PMID: 25514930 DOI: 10.1093/cvr/cvu249] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
AIMS P2X receptors (P2XRs) mediate sympathetic control and autoregulation of renal circulation triggering preglomerular vasoconstriction, which protects glomeruli from elevated pressures. Although previous studies established a casual link between glomerular susceptibility to hypertensive injury and decreased preglomerular vascular reactivity to P2XR activation, the mechanisms of attenuation of the P2XR signalling in hypertension remained unknown. We aimed to analyse molecular mechanisms of the impairment of P2XR signalling in renal vascular smooth muscle cells (RVSMCs) in genetic hypertension. METHODS AND RESULTS We compared the expression of pertinent genes and P2XR-linked Ca(2+) entry and Ca(2+) release mechanisms in RVSMCs of spontaneously hypertensive rats (SHRs) and their normotensive controls, Wistar Kyoto (WKY) rats. We found that, in SHR RVSMCs, P2XR-linked Ca(2+) entry and Ca(2+) release from the sarcoplasmic reticulum (SR) are both significantly reduced. The former is due to down-regulation of the P2X1 subunit. The latter is caused by a decrease of the SR Ca(2+) load. The SR Ca(2+) load reduction is caused by attenuated Ca(2+) uptake via down-regulated sarco-/endoplasmic reticulum Ca(2+)-ATPase 2b and elevated Ca(2+) leak from the SR via ryanodine receptors (RyRs) and inositol 1,4,5-trisphosphate receptors. Spontaneous activity of these Ca(2+)-release channels is augmented due to up-regulation of RyR type 2 and elevated IP3 production by up-regulated phospholipase C-β1. CONCLUSIONS Our study unravels the cellular and molecular mechanisms of attenuation of P2XR-mediated preglomerular vasoconstriction that elevates glomerular susceptibility to harmful hypertensive pressures. This provides an important impetus towards understanding of the pathology of hypertensive renal injury.
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Affiliation(s)
- Dmitri Gordienko
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Oleksandr Povstyan
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine Division of Basic Medical Sciences, St. George's, University of London, London, UK
| | - Khrystyna Sukhanova
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Maylis Raphaël
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
| | - Maksym Harhun
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine Division of Basic Medical Sciences, St. George's, University of London, London, UK
| | - Yulia Dyskina
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signaling, Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - V'yacheslav Lehen'kyi
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
| | - Abdirahman Jama
- MRC, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Zhi-Liang Lu
- MRC, Centre for Reproductive Health, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK Department of Biological Sciences, Xi'an Jiaotong-Liverpool University, Suzhou, China
| | - Roman Skryma
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
| | - Natalia Prevarskaya
- INSERM U1003, Laboratory of Excellence, Ion Channels Science and Therapeutics, Université des Sciences et Technologies de Lille, Batiment SN3, Villeneuve d'Ascq 59655, France
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17
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Harhun MI, Povstyan OV, Albert AP, Nichols CM. ATP-evoked sustained vasoconstrictions mediated by heteromeric P2X1/4 receptors in cerebral arteries. Stroke 2014; 45:2444-50. [PMID: 25070962 DOI: 10.1161/strokeaha.114.005544] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND PURPOSE Current knowledge states that vasoconstrictor responses to ATP are mediated by rapidly desensitizing ligand-gated P2X1 receptors in vascular smooth muscle cells (VSMCs). However, ATP is implicated in contributing to pathological conditions involving sustained vasoconstrictor response such as cerebral vasospasm. The purpose of this study is to test the hypothesis that the stimulation of VSMC P2XR receptors (P2XRs) contributes to ATP-evoked sustained vasoconstrictions in rat middle cerebral arteries (RMCAs). METHODS Reverse transcription- polymerase chain reaction, Western blot, and immunocytochemistry were used to analyze expression of mRNA and proteins in RMCAs VSMCs. Ionic currents and calcium responses were investigated using patch-clamp and confocal imaging techniques, respectively. Functional responses were confirmed using wire myography. RESULTS Expression of mRNA and protein for P2X1R and P2X4R subunits was identified in RMCA VSMCs. Confocal imaging in fluo-3-loaded VSMCs showed that ATP and a selective P2XR agonist, αβmeATP, evoked similar dose-dependent increases in [Ca(2+)]i. Patch-clamp experiments identified 2 components of P2XR-mediated currents: consisting of a fast desensitizing phase mediated by homomeric P2X1Rs and a slowly desensitizing phase involving heteromeric P2X1/4Rs. Isometric tension measurements showed that ≈80%:20% of initial ATP-evoked vasoconstriction in RMCA is mediated by homomeric P2X1Rs and heteromeric P2X1/4Rs, respectively. The sustained slowly desensitizing and rapidly recovering from desensitization responses are mediated by heteromeric P2X1/4Rs. CONCLUSIONS This study reveals for the first time that apart from rapidly desensitizing homomeric P2X1Rs, heteromeric P2X1/4Rs contribute to the sustained component of the purinergic-mediated vasoconstriction in RMCA. Our study, therefore, identifies possible novel targets for therapeutical intervention in cerebral circulation.
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Affiliation(s)
- Maksym I Harhun
- From the Division of Biomedical Sciences, St George's, University of London, London, United Kingdom (M.I.H., O.V.P., A.P.A., C.M.N.); and Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, Bogomoletz Institute of Physiology, Kyiv, Ukraine (O.V.P.).
| | - Oleksandr V Povstyan
- From the Division of Biomedical Sciences, St George's, University of London, London, United Kingdom (M.I.H., O.V.P., A.P.A., C.M.N.); and Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, Bogomoletz Institute of Physiology, Kyiv, Ukraine (O.V.P.)
| | - Anthony P Albert
- From the Division of Biomedical Sciences, St George's, University of London, London, United Kingdom (M.I.H., O.V.P., A.P.A., C.M.N.); and Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, Bogomoletz Institute of Physiology, Kyiv, Ukraine (O.V.P.)
| | - Claire M Nichols
- From the Division of Biomedical Sciences, St George's, University of London, London, United Kingdom (M.I.H., O.V.P., A.P.A., C.M.N.); and Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, Bogomoletz Institute of Physiology, Kyiv, Ukraine (O.V.P.)
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18
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Jones S, Evans RJ, Mahaut-Smith MP. Ca2+ influx through P2X1 receptors amplifies P2Y1 receptor-evoked Ca2+ signaling and ADP-evoked platelet aggregation. Mol Pharmacol 2014; 86:243-51. [PMID: 24923466 DOI: 10.1124/mol.114.092528] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Many cells express both P2X cation channels and P2Y G-protein-coupled receptors that are costimulated by nucleotides released during physiologic or pathophysiologic responses. For example, during hemostasis and thrombosis, ATP-gated P2X1 channels and ADP-stimulated P2Y1 and P2Y12 G-protein coupled receptors play important roles in platelet activation. It has previously been reported that P2X1 receptors amplify P2Y1-evoked Ca(2+) responses in platelets, but the underlying mechanism and influence on function is unknown. In human platelets, we show that maximally activated P2X1 receptors failed to stimulate significant aggregation but could amplify the aggregation response to a submaximal concentration of ADP. Costimulation of P2X1 and P2Y1 receptors generated a superadditive Ca(2+) increase in both human platelets and human embryonic kidney 293 (HEK293) cells via a mechanism dependent on Ca(2+) influx rather than Na(+) influx or membrane depolarization. The potentiation, due to an enhanced P2Y1 response, was observed if ADP was added up to 60 seconds after P2X1 activation. P2X1 receptors also enhanced Ca(2+) responses when costimulated with type 1 protease activated and M1 muscarinic acetylcholine receptors. The P2X1-dependent amplification of Gq-coupled [Ca(2+)]i increase was mimicked by ionomycin and was not affected by inhibition of protein kinase C, Rho-kinase, or extracellular signal-regulated protein kinase 1/2, which suggests that it results from potentiation of inositol 1,4,5-trisphosphate receptors and/or phospholipase C. We conclude that Ca(2+) influx through P2X1 receptors amplifies Ca(2+) signaling through P2Y1 and other Gq-coupled receptors. This represents a general form of co-incidence detection of ATP and coreleased agonists, such as ADP at sites of vascular injury or synaptic transmitters acting at metabotropic Gq-coupled receptors.
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Affiliation(s)
- Sarah Jones
- University of Leicester, Department of Cell Physiology and Pharmacology, Leicester, United Kingdom
| | - Richard J Evans
- University of Leicester, Department of Cell Physiology and Pharmacology, Leicester, United Kingdom
| | - Martyn P Mahaut-Smith
- University of Leicester, Department of Cell Physiology and Pharmacology, Leicester, United Kingdom
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19
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Vascular smooth muscle cells from small human omental arteries express P2X1 and P2X4 receptor subunits. Purinergic Signal 2014; 10:565-72. [PMID: 24845338 DOI: 10.1007/s11302-014-9415-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 05/08/2014] [Indexed: 02/06/2023] Open
Abstract
Stimulation of P2X receptors by ATP in vascular smooth muscle cells (VSMCs) is proposed to mediate vascular tone. However, understanding of P2X receptor-mediated actions in human blood vessels is limited, and therefore, the current work investigates the role of P2X receptors in freshly isolated small human gastro-omental arteries (HGOAs). Expression of P2X1 and P2X4 receptor subunit messenger RNA (mRNA) and protein was identified in individual HGOA VSMCs using RT-PCR and immunofluorescent analysis and using Western blot in multi-cellular preparations. ATP of 10 μmol/l and αβ-meATP of 10 μmol/l, a selective P2X receptor agonist, evoked robust increases in [Ca(2+)]i in fluo-3-loaded HGOA VSMCs. Pre-incubation with 1 μmol/l NF279, a selective P2X receptor antagonist, reduced the amplitude of αβ-meATP-induced increase in [Ca(2+)]i by about 70 %. ATP of 10 μmol/l and αβ-meATP of 10 μmol/l produced similar contractile responses in segments of HGOA, and these contractions were greatly reduced by 2 μmol/l NF449, a selective P2X receptor inhibitor. These data suggest that VSMCs from HGOA express P2X1 and P2X4 receptor subunits with homomeric P2X1 receptors likely serving as the predominant target for extracellular ATP.
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20
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Sukhanova KY, Thugorka OM, Bouryi VA, Harhun MI, Gordienko DV. Mechanisms of the sarcoplasmic reticulum Ca2+ release induced by P2X receptor activation in mesenteric artery myocytes. Pharmacol Rep 2014; 66:363-72. [PMID: 24905510 DOI: 10.1016/j.pharep.2013.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 10/09/2013] [Accepted: 11/26/2013] [Indexed: 10/25/2022]
Abstract
BACKGROUND ATP is one of the principal sympathetic neurotransmitters which contracts vascular smooth muscle cells (SMCs) via activation of ionotropic P2X receptors (P2XRs). We have recently demonstrated that contraction of the guinea pig small mesenteric arteries evoked by stimulation of P2XRs is sensitive to inhibitors of IP3 receptors (IP3Rs). Here we analyzed contribution of IP3Rs and ryanodine receptors (RyRs) to [Ca(2+)]i transients induced by P2XR agonist αβ-meATP (10 μM) in single SMCs from these vessels. METHODS The effects of inhibition of L-type Ca(2+) channels (VGCCs), RyRs and IP3Rs (5 μM nicardipine, 100 μM tetracaine and 30 μM 2-APB, respectively) on αβ-meATP-induced [Ca(2+)]i transients were analyzed using fast x-y confocal Ca(2+) imaging. RESULTS The effect of IP3R inhibition on the [Ca(2+)]i transient was significantly stronger (67 ± 7%) than that of RyR inhibition (40 ± 5%) and was attenuated by block of VGCCs. The latter indicates that activation of VGCCs is linked to IP3R-mediated Ca(2+) release. Immunostaining of RyRs and IP3Rs revealed that RyRs are located mainly in deeper sarcoplasmic reticulum (SR) while sub-plasma membrane (PM) SR elements are enriched with type 1 IP3Rs. This structural peculiarity makes IP3Rs more accessible to Ca(2+) entering the cell via VGCCs. Thus, IP3Rs may serve as an "intermediate amplifier" between voltage-gated Ca(2+) entry and RyR-mediated Ca(2+) release. CONCLUSIONS P2X receptor activation in mesenteric artery SMCs recruits IP3Rs-mediated Ca(2+) release from sub-PM SR, which is facilitated by activation of VGCCs. Sensitivity of IP3R-mediated release to VGCC antagonists in vascular SMCs makes this mechanism of special therapeutic significance.
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Affiliation(s)
- Khrystyna Yu Sukhanova
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, State Key Laboratory of Molecular and Cellular Biology, A.A. Bogomoletz Institute of Physiology, Kiev, Ukraine.
| | - Oleksandr M Thugorka
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, State Key Laboratory of Molecular and Cellular Biology, A.A. Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Vitali A Bouryi
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, State Key Laboratory of Molecular and Cellular Biology, A.A. Bogomoletz Institute of Physiology, Kiev, Ukraine
| | - Maksym I Harhun
- Division of Biomedical Sciences, St. George's, University of London, London, UK
| | - Dmitri V Gordienko
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, State Key Laboratory of Molecular and Cellular Biology, A.A. Bogomoletz Institute of Physiology, Kiev, Ukraine; Inserm U1003, Equipe labellisée par la Ligue Nationale Contre le Cancer, Université des Sciences et Technologies de Lille, Villeneuve d'Ascq, France.
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21
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Kur J, Newman EA. Purinergic control of vascular tone in the retina. J Physiol 2014; 592:491-504. [PMID: 24277867 PMCID: PMC3930435 DOI: 10.1113/jphysiol.2013.267294] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 11/18/2013] [Indexed: 12/19/2022] Open
Abstract
Purinergic control of vascular tone in the CNS has been largely unexplored. This study examines the contribution of endogenous extracellular ATP, acting on vascular smooth muscle cells, in controlling vascular tone in the in vivo rat retina. Retinal vessels were labelled by i.v. injection of a fluorescent dye and imaged with scanning laser confocal microscopy. The diameters of primary arterioles were monitored under control conditions and following intravitreal injection of pharmacological agents. Apyrase (500 units ml(-1)), an ATP hydrolysing enzyme, dilated retinal arterioles by 40.4 ± 2.8%, while AOPCP (12.5 mm), an ecto-5'-nucleotidase inhibitor that increases extracellular ATP levels, constricted arterioles by 58.0 ± 3.8% (P < 0.001 for both), demonstrating the importance of ATP in the control of basal vascular tone. Suramin (500 μm), a broad-spectrum P2 receptor antagonist, dilated retinal arterioles by 50.9 ± 3.7% (P < 0.001). IsoPPADS (300 μm) and TNP-ATP (50 μm), more selective P2X antagonists, dilated arterioles by 41.0 ± 5.3% and 55.2 ± 6.1% respectively (P < 0.001 for both). NF023 (50 μm), a potent antagonist of P2X1 receptors, dilated retinal arterioles by 32.1 ± 2.6% (P < 0.001). A438079 (500 μm) and AZ10606120 (50 μm), P2X7 antagonists, had no effect on basal vascular tone (P = 0.99 and P = 1.00 respectively). In the ex vivo retina, the P2X1 receptor agonist α,β-methylene ATP (300 nm) evoked sustained vasoconstrictions of 18.7 ± 3.2% (P < 0.05). In vivo vitreal injection of the gliotoxin fluorocitrate (150 μm) dilated retinal vessels by 52.3 ± 1.1% (P < 0.001) and inhibited the vasodilatory response to NF023 (50 μm, 7.9 ± 2.0%; P < 0.01). These findings suggest that vascular tone in rat retinal arterioles is maintained by tonic release of ATP from the retina. ATP acts on P2X1 receptors, although contributions from other P2X and P2Y receptors cannot be ruled out. Retinal glial cells are a possible source of the vasoconstricting ATP.
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Affiliation(s)
- Joanna Kur
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA.
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König S, Browne S, Doleschal B, Schernthaner M, Poteser M, Mächler H, Wittchow E, Braune M, Muik M, Romanin C, Groschner K. Inhibition of Orai1-mediated Ca(2+) entry is a key mechanism of the antiproliferative action of sirolimus in human arterial smooth muscle. Am J Physiol Heart Circ Physiol 2013; 305:H1646-57. [PMID: 24056904 DOI: 10.1152/ajpheart.00365.2013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sirolimus (rapamycin) is used in drug-eluting stent strategies and proved clearly superior in this application compared with other immunomodulators such as pimecrolimus. The molecular basis of this action of sirolimus in the vascular system is still incompletely understood. Measurements of cell proliferation in human coronary artery smooth muscle cells (hCASM) demonstrated a higher antiproliferative activity of sirolimus compared with pimecrolimus. Although sirolimus lacks inhibitory effects on calcineurin, nuclear factor of activated T-cell activation in hCASM was suppressed to a similar extent by both drugs at 10 μM. Sirolimus, but not pimecrolimus, inhibited agonist-induced and store-operated Ca(2+) entry as well as cAMP response element binding protein (CREB) phosphorylation in human arterial smooth muscle, suggesting the existence of an as-yet unrecognized inhibitory effect of sirolimus on Ca(2+) signaling and Ca(2+)-dependent gene transcription. Electrophysiological experiments revealed that only sirolimus but not pimecrolimus significantly blocked the classical stromal interaction molecule/Orai-mediated, store-operated Ca(2+) current reconstituted in human embryonic kidney cells (HEK293). A link between Orai function and proliferation was confirmed by dominant-negative knockout of Orai in hCASM. Analysis of the effects of sirolimus on cell proliferation and CREB activation in an in vitro model of arterial intervention using human aorta corroborated the ability of sirolimus to suppress stent implantation-induced CREB activation in human arteries. We suggest inhibition of store-operated Ca(2+) entry based on Orai channels and the resulting suppression of Ca(2+) transcription coupling as a key mechanism underlying the antiproliferative activity of sirolimus in human arteries. This mechanism of action is specific for sirolimus and not a general feature of drugs interacting with FK506-binding proteins.
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Affiliation(s)
- Sarah König
- Institute of Biophysics, Medical University of Graz, Graz, Austria
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Westcott EB, Segal SS. Perivascular innervation: a multiplicity of roles in vasomotor control and myoendothelial signaling. Microcirculation 2013; 20:217-38. [PMID: 23289720 DOI: 10.1111/micc.12035] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 12/25/2012] [Indexed: 12/30/2022]
Abstract
The control of vascular resistance and tissue perfusion reflect coordinated changes in the diameter of feed arteries and the arteriolar networks they supply. Against a background of myogenic tone and metabolic demand, vasoactive signals originating from perivascular sympathetic and sensory nerves are integrated with endothelium-derived signals to produce vasodilation or vasoconstriction. PVNs release adrenergic, cholinergic, peptidergic, purinergic, and nitrergic neurotransmitters that lead to SMC contraction or relaxation via their actions on SMCs, ECs, or other PVNs. ECs release autacoids that can have opposing actions on SMCs. Respective cell layers are connected directly to each other through GJs at discrete sites via MEJs projecting through holes in the IEL. Whereas studies of intercellular communication in the vascular wall have centered on endothelium-derived signals that govern SMC relaxation, attention has increasingly focused on signaling from SMCs to ECs. Thus, via MEJs, neurotransmission from PVNs can evoke distinct responses from ECs subsequent to acting on SMCs. To integrate this emerging area of investigation in light of vasomotor control, the present review synthesizes current understanding of signaling events that originate within SMCs in response to perivascular neurotransmission in light of EC feedback. Although often ignored in studies of the resistance vasculature, PVNs are integral to blood flow control and can provide a physiological stimulus for myoendothelial communication. Greater understanding of these underlying signaling events and how they may be affected by aging and disease will provide new approaches for selective therapeutic interventions.
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Affiliation(s)
- Erika B Westcott
- Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri 65212, USA
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Sukhanova KY, Harhun MI, Bouryi VA, Gordienko DV. Mechanisms of [Ca2+]i elevation following P2X receptor activation in the guinea-pig small mesenteric artery myocytes. Pharmacol Rep 2013; 65:152-63. [PMID: 23563033 DOI: 10.1016/s1734-1140(13)70973-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 09/24/2012] [Indexed: 11/25/2022]
Abstract
BACKGROUND There is growing evidence suggesting involvement of L-type voltage-gated Ca2+ channels (VGCCs) in purinergic signaling mechanisms. However, detailed interplay between VGCCs and P2X receptors in intracellular Ca2+ mobilization is not well understood. This study examined relative contribution of the Ca2+ entry mechanisms and induced by this entry Ca2+ release from the intracellular stores engaged by activation of P2X receptors in smooth muscle cells (SMCs) from the guinea-pig small mesenteric arteries. METHODS P2X receptors were stimulated by the brief local application of αβ-meATP and changes in [Ca2+]i were monitored in fluo-3 loaded SMCs using fast x-y confocal Ca2+ imaging. The effects of the block of L-type VGCCs and/or depletion of the intracellular Ca2+ stores on αβ-meATP-induced [Ca2+]i transients were analyzed. RESULTS Our analysis revealed that Ca2+ entry via L-type VGCCs is augmented by the Ca2+-induced Ca2+ release significantly more than Ca2+ entry via P2X receptors, even though net Ca2+ influxes provided by the two mechanisms are not significantly different. CONCLUSIONS Thus, arterial SMCs upon P2X receptor activation employ an effective mechanism of the Ca2+ signal amplification, the major component of which is the Ca2+ release from the SR activated by Ca2+ influx via L-type VGCCs. This signaling pathway is engaged by depolarization of the myocyte membrane resulting from activation of P2X receptors, which, being Ca2+ permeable, per se form less effective Ca2+ signaling pathway. This study, therefore, rescales potential targets for therapeutic intervention in purinergic control of vascular tone.
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Affiliation(s)
- Khrystyna Yu Sukhanova
- Laboratory of Molecular Pharmacology and Biophysics of Cell Signalling, A.A. Bogomoletz, Institute of Physiology, Bogomoletz 4, Kiev, 01024, Ukraine.
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Birch RE, Schwiebert EM, Peppiatt-Wildman CM, Wildman SS. Emerging key roles for P2X receptors in the kidney. Front Physiol 2013; 4:262. [PMID: 24098285 PMCID: PMC3785026 DOI: 10.3389/fphys.2013.00262] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/05/2013] [Indexed: 12/29/2022] Open
Abstract
P2X ionotropic non-selective cation channels are expressed throughout the kidney and are activated in a paracrine or autocrine manner following the binding of extracellular ATP and related extracellular nucleotides. Whilst there is a wealth of literature describing a regulatory role of P2 receptors (P2R) in the kidney, there are significantly less data on the regulatory role of P2X receptors (P2XR) compared with that described for metabotropic P2Y. Much of the historical literature describing a role for P2XR in the kidney has focused heavily on the role of P2X1R in the autoregulation of renal blood flow. More recently, however, there has been a plethora of manuscripts providing compelling evidence for additional roles for P2XR in both kidney health and disease. This review summarizes the current evidence for the involvement of P2XR in the regulation of renal tubular and vascular function, and highlights the novel data describing their putative roles in regulating physiological and pathophysiological processes in the kidney.
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Affiliation(s)
- R. E. Birch
- Medway School of Pharmacy, The Universities of Kent and GreenwichKent, UK
| | | | | | - S. S. Wildman
- Medway School of Pharmacy, The Universities of Kent and GreenwichKent, UK
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26
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Opiates Modulate Thermosensation by Internalizing Cold Receptor TRPM8. Cell Rep 2013; 4:504-15. [DOI: 10.1016/j.celrep.2013.07.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 06/07/2013] [Accepted: 07/01/2013] [Indexed: 11/21/2022] Open
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Ulrich H, Abbracchio MP, Burnstock G. Extrinsic purinergic regulation of neural stem/progenitor cells: implications for CNS development and repair. Stem Cell Rev Rep 2012; 8:755-67. [PMID: 22544361 DOI: 10.1007/s12015-012-9372-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
There has been tremendous progress in understanding neural stem cell (NSC) biology, with genetic and cell biological methods identifying sequential gene expression and molecular interactions guiding NSC specification into distinct neuronal and glial populations during development. Data has emerged on the possible exploitation of NSC-based strategies to repair adult diseased brain. However, despite increased information on lineage specific transcription factors, cell-cycle regulators and epigenetic factors involved in the fate and plasticity of NSCs, understanding of extracellular cues driving the behavior of embryonic and adult NSCs is still very limited. Knowledge of factors regulating brain development is crucial in understanding the pathogenetic mechanisms of brain dysfunction. Since injury-activated repair mechanisms in adult brain often recapitulate ontogenetic events, the identification of these players will also reveal novel regenerative strategies. Here, we highlight the purinergic system as a key emerging player in the endogenous control of NSCs. Purinergic signalling molecules (ATP, UTP and adenosine) act with growth factors in regulating the synchronized proliferation, migration, differentiation and death of NSCs during brain and spinal cord development. At early stages of development, transient and time-specific release of ATP is critical for initiating eye formation; once anatomical CNS structures are defined, purinergic molecules participate in calcium-dependent neuron-glia communication controlling NSC behaviour. When development is complete, some purinergic mechanisms are silenced, but can be re-activated in adult brain after injury, suggesting a role in regeneration and self-repair. Targeting the purinergic system to develop new strategies for neurodevelopmental disorders and neurodegenerative diseases will be also discussed.
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Affiliation(s)
- Henning Ulrich
- Departamento de Bioquimica, Instituto de Quimica, Universidade de São Paulo, Av. Prof. Lineu Prestes, 748, São Paulo 05508-900, SP, Brazil.
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Harhun MI, Huggins CL, Ratnasingham K, Raje D, Moss RF, Szewczyk K, Vasilikostas G, Greenwood IA, Khong TK, Wan A, Reddy M. Resident phenotypically modulated vascular smooth muscle cells in healthy human arteries. J Cell Mol Med 2012; 16:2802-12. [PMID: 22862785 PMCID: PMC3492755 DOI: 10.1111/j.1582-4934.2012.01609.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2012] [Accepted: 07/13/2012] [Indexed: 12/24/2022] Open
Abstract
Vascular interstitial cells (VICs) are non-contractile cells with filopodia previously described in healthy blood vessels of rodents and their function remains unknown. The objective of this study was to identify VICs in human arteries and to ascertain their role. VICs were identified in the wall of human gastro-omental arteries using transmission electron microscopy. Isolated VICs showed ability to form new and elongate existing filopodia and actively change body shape. Most importantly sprouting VICs were also observed in cell dispersal. RT-PCR performed on separately collected contractile vascular smooth muscle cells (VSMCs) and VICs showed that both cell types expressed the gene for smooth muscle myosin heavy chain (SM-MHC). Immunofluorescent labelling showed that both VSMCs and VICs had similar fluorescence for SM-MHC and αSM-actin, VICs, however, had significantly lower fluorescence for smoothelin, myosin light chain kinase, h-calponin and SM22α. It was also found that VICs do not have cytoskeleton as rigid as in contractile VSMCs. VICs express number of VSMC-specific proteins and display features of phenotypically modulated VSMCs with increased migratory abilities. VICs, therefore represent resident phenotypically modulated VSMCs that are present in human arteries under normal physiological conditions.
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Affiliation(s)
- Maksym I Harhun
- Pharmacology and Cell Physiology Research Group, Division of Biomedical Sciences, St. George's, University of London, London, United Kingdom.
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Chao CC, Huang CC, Lu DY, Wong KL, Chen YR, Cheng TH, Leung YM. Ca2+ store depletion and endoplasmic reticulum stress are involved in P2X7 receptor-mediated neurotoxicity in differentiated NG108-15 cells. J Cell Biochem 2012; 113:1377-85. [PMID: 22134903 DOI: 10.1002/jcb.24010] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
P2X7 receptor (P2X7R) activation by extracellular ATP triggers influx of Na(+) and Ca(2+), cytosolic Ca(2+) overload and consequently cytotoxicity. Whether disturbances in endoplasmic reticulum (ER) Ca(2+) homeostasis and ER stress are involved in P2X7R-mediated cell death is unknown. In this study, a P2X7R agonist (BzATP) was used to activate P2X7R in differentiated NG108-15 neuronal cells. In a concentration-dependent manner, application of BzATP (10-100 µM) immediately raised cytosolic Ca(2+) concentration ([Ca(2+)]i) and caused cell death after a 24-h incubation. P2X7R activation for 2 h did not cause cell death but resulted in a sustained reduction in ER Ca2+ pool size, as evidenced by a diminished cyclopiazonic acid-induced Ca(2+) discharge (fura 2 assay) and a lower fluorescent signal in cells loaded with Mag-fura 2 (ER-specific Ca(2+)-fluorescent dye). Furthermore, P2X7R activation (2 h) led to the appearance of markers of ER stress [phosphorylated α subunit of eukaryotic initiation factor 2 (p-eIF2α) and C/EBP homologous protein (CHOP)] and apoptosis (cleaved caspase 3). Xestospongin C (XeC), an antagonist of inositol-1,4,5-trisphosphate (IP3) receptor (IP3R), strongly inhibited BzATP-triggered [Ca(2+)]i elevation, suggesting that the latter involved Ca(2+) release via IP3R. XeC pretreatment not only attenuated the reduction in Ca(2+) pool size in BzATP-treated cells, but also rescued cell death and prevented BzATP-induced appearance of ER stress and apoptotic markers. These novel observations suggest that P2X7R activation caused not only Ca(2+) overload, but also Ca(2+) release via IP3R, sustained Ca(2+) store depletion, ER stress and eventually apoptotic cell death.
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Affiliation(s)
- Chia-Chia Chao
- Department of Life Sciences, National Chung Hsing University, Taichung, 402, Taiwan
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Guan Z, Inscho EW. Role of adenosine 5'-triphosphate in regulating renal microvascular function and in hypertension. Hypertension 2011; 58:333-40. [PMID: 21768526 DOI: 10.1161/hypertensionaha.110.155952] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
ATP is an essential energy substrate for cellular metabolism, but it can also influence many biological processes when released into the extracellular milieu. Research has established that extracellular ATP acts as an autocrine/paracrine factor that regulates many physiological functions. Alternatively, excessive extracellular ATP levels contribute to pathophysiological processes, such as inflammation, cell proliferation and apoptosis, and atherosclerosis. Renal P2 receptors are widely distributed throughout glomeruli, vasculature, and tubular segments and participate in controlling renal vascular resistance, mediating renal autoregulation, and regulating tubular transport function. This review will focus on the role of ATP-P2 receptor signaling in regulating renal microvascular function and autoregulation, recent advances on the role of ATP-P2 signaling in hypertension-associated renal vascular injury, and emerging new directions.
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Affiliation(s)
- Zhengrong Guan
- Department of Physiology CA3137, Georgia Health Sciences University, 1120 15th St, Augusta, GA 30912, USA
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