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Zhang F, Armando I, Jose PA, Zeng C, Yang J. G protein-coupled receptor kinases in hypertension: physiology, pathogenesis, and therapeutic targets. Hypertens Res 2024:10.1038/s41440-024-01763-y. [PMID: 38961282 DOI: 10.1038/s41440-024-01763-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 05/10/2024] [Accepted: 06/06/2024] [Indexed: 07/05/2024]
Abstract
G protein-coupled receptors (GPCRs) mediate cellular responses to a myriad of hormones and neurotransmitters that play vital roles in the regulation of physiological processes such as blood pressure. In organs such as the artery and kidney, hormones or neurotransmitters, such as angiotensin II (Ang II), dopamine, epinephrine, and norepinephrine exert their functions via their receptors, with the ultimate effect of keeping normal vascular reactivity, normal body sodium, and normal blood pressure. GPCR kinases (GRKs) exert their biological functions, by mediating the regulation of agonist-occupied GPCRs, non-GPCRs, or non-receptor substrates. In particular, increasing number of studies show that aberrant expression and activity of GRKs in the cardiovascular system and kidney inhibit or stimulate GPCRs (e.g., dopamine receptors, Ang II receptors, and α- and β-adrenergic receptors), resulting in hypertension. Current studies focus on the effect of selective GRK inhibitors in cardiovascular diseases, including hypertension. Moreover, genetic studies show that GRK gene variants are associated with essential hypertension, blood pressure response to antihypertensive medicines, and adverse cardiovascular outcomes of antihypertensive treatment. In this review, we present a comprehensive overview of GRK-mediated regulation of blood pressure, role of GRKs in the pathogenesis of hypertension, and highlight potential strategies for the treatment of hypertension. Schematic representation of GPCR desensitization process. Activation of GPCRs begins with the binding of an agonist to its corresponding receptor. Then G proteins activate downstream effectors that are mediated by various signaling pathways. GPCR signaling is halted by GRK-mediated receptor phosphorylation, which causes receptor internalization through β-arrestin.
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Affiliation(s)
- Fuwei Zhang
- Research Center for Metabolic and Cardiovascular Diseases, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, PR China
- Department of Nutrition, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, PR China
- Department of Cardiology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, PR China
| | - Ines Armando
- Division of Renal Diseases & Hypertension, Department of Medicine and Department of Physiology/Pharmacology, The George Washington University School of Medicine & Health Sciences, Washington, DC, USA
| | - Pedro A Jose
- Division of Renal Diseases & Hypertension, Department of Medicine and Department of Physiology/Pharmacology, The George Washington University School of Medicine & Health Sciences, Washington, DC, USA
| | - Chunyu Zeng
- Department of Cardiology, Daping Hospital, The Third Military Medical University (Army Medical University), Chongqing, PR China
- Chongqing Key Laboratory for Hypertension Research, Chongqing Cardiovascular Clinical Research Center, Chongqing Institute of Cardiology, Chongqing, PR China
| | - Jian Yang
- Research Center for Metabolic and Cardiovascular Diseases, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, PR China.
- Department of Nutrition, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, PR China.
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2
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Alonazi A, Nash CA, Wang CH, Christofidou E, Challiss RAJ, Willets JM. GRK2 expression and catalytic activity are essential for vasoconstrictor/ERK-stimulated arterial smooth muscle proliferation. Biochem Pharmacol 2023; 216:115795. [PMID: 37690571 DOI: 10.1016/j.bcp.2023.115795] [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: 07/10/2023] [Revised: 09/07/2023] [Accepted: 09/07/2023] [Indexed: 09/12/2023]
Abstract
Prolonged vasoconstrictor signalling found in hypertension, increases arterial contraction, and alters vessel architecture by stimulating arterial smooth muscle cell (ASMC) growth, underpinning the development of re-stenosis lesions and vascular remodelling. Vasoconstrictors interact with their cognate G protein coupled receptors activating a variety of signalling pathways to promote smooth muscle proliferation. Here, angiotensin II (AngII) and endothelin 1 (ET1), but not UTP stimulates ASMC proliferation. Moreover, siRNA-mediated depletion of endogenous GRK2 expression, or GRK2 inhibitors, compound 101 or paroxetine, prevented AngII and ET1-promoted ASMC growth. Depletion of GRK2 expression or inhibition of GRK2 activity ablated the prolonged phase of AngII and ET-stimulated ERK signalling, while enhancing and prolonging UTP-stimulated ERK signalling. Increased GRK2 expression enhanced and prolonged AngII and ET1-stimulated ERK signalling, but suppressed UTP-stimulated ERK signalling. In ASMC prepared from 6-week-old WKY and SHR, AngII and ET1-stimulated proliferation rates were similar, however, in cultures prepared from 12-week-old rats AngII and ET1-stimulated growth was enhanced in SHR-derived ASMC, which was reversed following depletion of GRK2 expression. Furthermore, in ASMC cultures isolated from 6-week-old WKY and SHR rats, AngII and ET1-stimulated ERK signals were similar, while in cultures from 12-week-old rats ERK signals were both enhanced and prolonged in SHR-derived ASMC, and were reversed to those seen in age-matched WKY-derived ASMC following pre-treatment of SHR-derived ASMC with compound 101. These data indicate that the presence of GRK2 and its catalytic activity are essential to enable pro-proliferative vasoconstrictors to promote growth via recruitment and activation of the ERK signalling pathway in ASMC.
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Affiliation(s)
- Asma Alonazi
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom; Department of Pharmacology and Toxicology, Pharmacy College, King Saud University, Riyadh, P.O. Box 145111, Saudi Arabia(1)
| | - Craig A Nash
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom; Cardiovascular Metabolism, Novartis Institutes for Biomedical Research, 22 Windsor Street, Cambridge, MA 02139, USA
| | - Chuan-Han Wang
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom
| | - Elena Christofidou
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom; Tumor Viruses and Cancer Laboratory, Department of Biological Sciences, University of Cyprus, Panepistimiou 1, Aglantzia 2109, Nicosia, Cyprus(1)
| | - R A John Challiss
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom
| | - Jonathon M Willets
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom.
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3
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The P2Y 2 Receptor C-Terminal Tail Modulates but Is Dispensable for β-Arrestin Recruitment. Int J Mol Sci 2022; 23:ijms23073460. [PMID: 35408820 PMCID: PMC8999042 DOI: 10.3390/ijms23073460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/17/2022] [Accepted: 03/18/2022] [Indexed: 02/05/2023] Open
Abstract
The P2Y2 receptor (P2Y2R) is a G protein-coupled receptor that is activated by extracellular ATP and UTP, to a similar extent. This allows it to play roles in the cell's response to the (increased) release of these nucleotides, e.g., in response to stress situations, including mechanical stress and oxygen deprivation. However, despite its involvement in important (patho)physiological processes, the intracellular signaling induced by the P2Y2R remains incompletely described. Therefore, this study implemented a NanoBiT® functional complementation assay to shed more light on the recruitment of β-arrestins (βarr1 and βarr2) upon receptor activation. More specifically, upon determination of the optimal configuration in this assay system, the effect of different (receptor) residues/regions on βarr recruitment to the receptor in response to ATP or UTP was estimated. To this end, the linker was shortened, the C-terminal tail was truncated, and phosphorylatable residues in the third intracellular loop of the receptor were mutated, in either singly or multiply adapted constructs. The results showed that none of the introduced adaptations entirely abolished the recruitment of either βarr, although EC50 values differed and time-luminescence profiles appeared to be qualitatively altered. The results hint at the C-terminal tail modulating the interaction with βarr, while not being indispensable.
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4
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Shihan M, Novoyatleva T, Lehmeyer T, Sydykov A, Schermuly RT. Role of the Purinergic P2Y2 Receptor in Pulmonary Hypertension. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182111009. [PMID: 34769531 PMCID: PMC8582672 DOI: 10.3390/ijerph182111009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 11/29/2022]
Abstract
Pulmonary arterial hypertension (PAH), group 1 pulmonary hypertension (PH), is a fatal disease that is characterized by vasoconstriction, increased pressure in the pulmonary arteries, and right heart failure. PAH can be described by abnormal vascular remodeling, hyperproliferation in the vasculature, endothelial cell dysfunction, and vascular tone dysregulation. The disease pathomechanisms, however, are as yet not fully understood at the molecular level. Purinergic receptors P2Y within the G-protein-coupled receptor family play a major role in fluid shear stress transduction, proliferation, migration, and vascular tone regulation in systemic circulation, but less is known about their contribution in PAH. Hence, studies that focus on purinergic signaling are of great importance for the identification of new therapeutic targets in PAH. Interestingly, the role of P2Y2 receptors has not yet been sufficiently studied in PAH, whereas the relevance of other P2Ys as drug targets for PAH was shown using specific agonists or antagonists. In this review, we will shed light on P2Y receptors and focus more on the P2Y2 receptor as a potential novel player in PAH and as a new therapeutic target for disease management.
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5
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Alonazi ASA, Willets JM. G protein-coupled receptor kinase 2 is essential to enable vasoconstrictor-mediated arterial smooth muscle proliferation. Cell Signal 2021; 88:110152. [PMID: 34555505 DOI: 10.1016/j.cellsig.2021.110152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/07/2021] [Accepted: 09/15/2021] [Indexed: 01/05/2023]
Abstract
Hypertension is associated with increased production and circulation of vasoconstrictors, resulting in enhanced signalling through their cognate G protein-coupled receptors (GPCR). Prolonged vasoconstrictor GPCR signalling increases arterial contraction and stimulates signalling pathways that promote vascular smooth muscle cell (VSMC) proliferation, contributing to the development of atherosclerotic plaques, re-stenosis lesions and vascular remodelling. GPCR signalling through phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) promotes VSMC proliferation. In VSMC, G protein-coupled receptor kinase 2 (GRK2) is known to regulate numerous vasoconstrictor GPCRs and their downstream signalling pathways. As GRK2 is implicated in controlling various aspects of cellular growth, we examined whether GRK2 could affect VSMC proliferation. Using two indices of cell growth, we show that PI3K inhibition and depletion of GRK2 expression produced a similar ablation of pro-proliferative vasoconstrictor-stimulated VSMC growth. Furthermore, GRK2-knockdown ablated the sustained phase of endothelin-1 and angiotensin-II-stimulated Akt phosphorylation, whilst the peak (5 min) phase was unaffected. Conversely, the GRK2 inhibitor compound 101 did not affect vasoconstrictor-driven Akt phosphorylation. Vasoconstrictor-stimulated phosphorylation of the Akt substrates GSK3α and GSK3β was ablated following RNAi-mediated GRK2 depletion, or after PI3K inhibition. Moreover, GRK2 knockdown prevented endothelin-1 and angiotensin-II from increasing cyclin D1 expression. These data suggest GRK2 expression is essential to facilitate vasoconstrictor-driven VSMC proliferation through its ability to promote efficient prolonged PI3K-Akt signalling, and thus relieve the GSK3-mediated block on cell cycling. Considering VSMC GRK2 expression increases early in the development of hypertension, this highlights the potential for GRK2 to promote VSMC growth and exacerbate hypertensive pathophysiological vascular remodelling.
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Affiliation(s)
- Asma S A Alonazi
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom; Department of Pharmacology and Toxicology, Pharmacy College, King Saud University, Riyadh, Saudi Arabia
| | - Jonathon M Willets
- Department of Molecular and Cell Biology, Henry Wellcome Building, University of Leicester, Lancaster Road, Leicester LE1 7RH, United Kingdom.
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6
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Pathania AS, Ren X, Mahdi MY, Shackleford GM, Erdreich-Epstein A. GRK2 promotes growth of medulloblastoma cells and protects them from chemotherapy-induced apoptosis. Sci Rep 2019; 9:13902. [PMID: 31554835 PMCID: PMC6761358 DOI: 10.1038/s41598-019-50157-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 09/03/2019] [Indexed: 02/07/2023] Open
Abstract
G-protein coupled receptor kinase 2 (GRK2; ADRBK1, BARK1) is most known as a regulator of G-protein coupled receptors. However, GRK2 also has other functions. Medulloblastomas are the most common malignant brain cancers in children. GRK2 has not been implicated in medulloblastoma biology. Here we report that GRK2 knockdown slowed cell growth, diminished proliferation, and enhanced cisplatin- and etoposide-induced apoptosis in medulloblastoma cell lines UW228-2 and Daoy. Reciprocally, GRK2 overexpression attenuated apoptosis induced by these chemotherapy drugs. Cisplatin and etoposide increased phosphorylation of AKT (S473) and GRK2 knockdown mitigated this increase. Cisplatin and etoposide attenuated ERK phosphorylation, but GRK2 knockdown did not alter this effect. Wildtype GRK2 reversed the increase in cisplatin- and etoposide-induced apoptosis caused by GRK2 knockdown. GRK2-K220R (kinase dead) and GRK2-S670A (unphosphorylated, constitutively active) conferred protection from cisplatin that was similar to wildtype GRK2, suggesting that this protection may be mediated though a kinase-independent activity of GRK2. These data demonstrate that GRK2 contributes to proliferation and survival of these medulloblastoma cell lines and to their protection from cisplatin- and etoposide-induced apoptosis.
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Affiliation(s)
- Anup S Pathania
- Department of Pediatrics, Division of Hematology, Oncology and Blood and Marrow Transplantation, The Saban Research Institute at Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Xiuhai Ren
- Department of Pediatrics, Division of Hematology, Oncology and Blood and Marrow Transplantation, The Saban Research Institute at Children's Hospital Los Angeles, Los Angeles, California, USA
| | - Min Y Mahdi
- Department of Radiology, The Saban Research Institute at Children's Hospital Los Angeles, Los Angeles, California, USA
| | - Gregory M Shackleford
- Department of Radiology, The Saban Research Institute at Children's Hospital Los Angeles, Los Angeles, California, USA
| | - Anat Erdreich-Epstein
- Department of Pediatrics, Division of Hematology, Oncology and Blood and Marrow Transplantation, The Saban Research Institute at Children's Hospital Los Angeles and Keck School of Medicine and Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California, USA.
- Department of Pathology, Children's Hospital Los Angeles and Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
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7
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von Kügelgen I. Pharmacology of P2Y receptors. Brain Res Bull 2019; 151:12-24. [PMID: 30922852 DOI: 10.1016/j.brainresbull.2019.03.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 03/04/2019] [Accepted: 03/17/2019] [Indexed: 01/17/2023]
Abstract
P2Y receptors are G-protein-coupled receptors (GPCRs) for extracellular nucleotides. There are eight mammalian P2Y receptor subtypes divided into two subgroups (P2Y1, P2Y2, P2Y4, P2Y6, and P2Y11) and (P2Y12, P2Y13, and P2Y14). The P2Y receptors are expressed in various cell types and play important roles in physiology and pathophysiology including inflammatory responses and neuropathic pain. The antagonism of P2Y12 receptors is used in pharmacotherapy for the prevention and therapy of cardiovascular events. The nucleoside analogue ticagrelor and active metabolites of the thienopyridine compounds ticlopidine, clopidogrel and prasugrel inhibit platelet P2Y12 receptors and reduce thereby platelet aggregation. The P2Y2 receptor agonist diquafosol is used for the treatment of the dry eye syndrome. The P2Y receptor subtypes differ in their amino acid sequences, their pharmacological profiles and their signaling transduction pathways. Recently, selective receptor ligands have been developed for all subtypes. The published crystal structures of the human P2Y1 and P2Y12 receptors as well as receptor models will facilitate the development of novel drugs for pharmacotherapy.
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Affiliation(s)
- Ivar von Kügelgen
- Department of Pharmacology and Toxicology, Pharma Center, University of Bonn, D-53127, Bonn, Germany.
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8
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Murga C, Arcones AC, Cruces-Sande M, Briones AM, Salaices M, Mayor F. G Protein-Coupled Receptor Kinase 2 (GRK2) as a Potential Therapeutic Target in Cardiovascular and Metabolic Diseases. Front Pharmacol 2019; 10:112. [PMID: 30837878 PMCID: PMC6390810 DOI: 10.3389/fphar.2019.00112] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 01/28/2019] [Indexed: 12/20/2022] Open
Abstract
G protein-coupled receptor kinase 2 (GRK2) is a central signaling node involved in the modulation of many G protein-coupled receptors (GPCRs) and also displaying regulatory functions in other cell signaling routes. GRK2 levels and activity have been reported to be enhanced in patients or in preclinical models of several relevant pathological situations, such as heart failure, cardiac hypertrophy, hypertension, obesity and insulin resistance conditions, or non-alcoholic fatty liver disease (NAFLD), and to contribute to disease progression by a variety of mechanisms related to its multifunctional roles. Therefore, targeting GRK2 by different strategies emerges as a potentially relevant approach to treat cardiovascular disease, obesity, type 2 diabetes, or NAFLD, pathological conditions which are frequently interconnected and present as co-morbidities.
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Affiliation(s)
- Cristina Murga
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (UAM-CSIC), Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain.,Instituto de Investigación Sanitaria La Princesa, Madrid, Spain
| | - Alba C Arcones
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (UAM-CSIC), Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain.,Instituto de Investigación Sanitaria La Princesa, Madrid, Spain
| | - Marta Cruces-Sande
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (UAM-CSIC), Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain.,Instituto de Investigación Sanitaria La Princesa, Madrid, Spain
| | - Ana M Briones
- CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain.,Departamento de Farmacología, Universidad Autónoma de Madrid (UAM), Madrid, Spain.,Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - Mercedes Salaices
- CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain.,Departamento de Farmacología, Universidad Autónoma de Madrid (UAM), Madrid, Spain.,Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid, Spain
| | - Federico Mayor
- Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (UAM-CSIC), Universidad Autónoma de Madrid, Madrid, Spain.,CIBER de Enfermedades Cardiovasculares (CIBERCV), Instituto de Salud Carlos III, Madrid, Spain.,Instituto de Investigación Sanitaria La Princesa, Madrid, Spain
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9
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Differential regulation of β2-adrenoceptor and adenosine A2B receptor signalling by GRK and arrestin proteins in arterial smooth muscle. Cell Signal 2018; 51:86-98. [DOI: 10.1016/j.cellsig.2018.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 07/13/2018] [Accepted: 07/29/2018] [Indexed: 10/28/2022]
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10
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Rainbow RD, Brennan S, Jackson R, Beech AJ, Bengreed A, Waldschmidt HV, Tesmer JJG, Challiss RAJ, Willets JM. Small-Molecule G Protein-Coupled Receptor Kinase Inhibitors Attenuate G Protein-Coupled Receptor Kinase 2-Mediated Desensitization of Vasoconstrictor-Induced Arterial Contractions. Mol Pharmacol 2018; 94:1079-1091. [PMID: 29980659 DOI: 10.1124/mol.118.112524] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 06/29/2018] [Indexed: 01/01/2023] Open
Abstract
Vasoconstrictor-driven G protein-coupled receptor (GPCR)/phospholipase C (PLC) signaling increases intracellular Ca2+ concentration to mediate arterial contraction. To counteract vasoconstrictor-induced contraction, GPCR/PLC signaling can be desensitized by G protein-coupled receptor kinases (GRKs), with GRK2 playing a predominant role in isolated arterial smooth muscle cells. In this study, we use an array of GRK2 inhibitors to assess their effects on the desensitization of UTP and angiotensin II (AngII)-mediated arterial contractions. The effects of GRK2 inhibitors on the desensitization of UTP- or AngII-stimulated mesenteric third-order arterial contractions, and PLC activity in isolated mesenteric smooth muscle cells (MSMC), were determined using wire myography and Ca2+ imaging, respectively. Applying a stimulation protocol to cause receptor desensitization resulted in reductions in UTP- and AngII-stimulated arterial contractions. Preincubation with the GRK2 inhibitor paroxetine almost completely prevented desensitization of UTP- and attenuated desensitization of AngII-stimulated arterial contractions. In contrast, fluoxetine was ineffective. Preincubation with alternative GRK2 inhibitors (Takeda compound 101 or CCG224063) also attenuated the desensitization of UTP-mediated arterial contractile responses. In isolated MSMC, paroxetine, Takeda compound 101, and CCG224063 also attenuated the desensitization of UTP- and AngII-stimulated increases in Ca2+, whereas fluoxetine did not. In human uterine smooth muscle cells, paroxetine reversed GRK2-mediated histamine H1 receptor desensitization, but not GRK6-mediated oxytocin receptor desensitization. Utilizing various small-molecule GRK2 inhibitors, we confirm that GRK2 plays a central role in regulating vasoconstrictor-mediated arterial tone, highlighting a potentially novel strategy for blood pressure regulation through targeting GRK2 function.
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Affiliation(s)
- Richard D Rainbow
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - Sean Brennan
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - Robert Jackson
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - Alison J Beech
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - Amal Bengreed
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - Helen V Waldschmidt
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - John J G Tesmer
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - R A John Challiss
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
| | - Jonathon M Willets
- Department of Molecular and Cell Biology, University of Leicester, Leicester, United Kingdom (A.B., R.A.J.C., J.M.W.); Department of Cardiovascular Sciences, University of Leicester, Clinical Sciences Wing, Glenfield General Hospital, Leicester, United Kingdom (R.D.R., S.B., R.J., A.J.B.); Life Sciences Institute and Departments of Pharmacology, Biological Sciences, and Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan (H.V.W., J.J.G.T.); and Department of Biological Sciences, Purdue University, West Lafayette, Indiana (J.J.G.T.)
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11
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Gendron FP, Placet M, Arguin G. P2Y 2 Receptor Functions in Cancer: A Perspective in the Context of Colorectal Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1051:91-106. [PMID: 28815512 DOI: 10.1007/5584_2017_90] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Purinergic signaling has recently emerged as a network of signaling molecules, enzymes and receptors that coordinates the action and behavior of cancerous cells. Extracellular adenosine 5' triphosphate activates a plethora of P2 nucleotide receptors that can putatively modulate cancer cell proliferation, survival and dissemination. In this context, the G protein-coupled P2Y2 receptor was identified as one of the entities coordinating the cellular and molecular events that characterize cancerous cells. In this chapter, we will look at the contribution of the P2Y2 receptor in cancer outcomes and use this information to demonstrate that the P2Y2 receptor represents a drug target of interest in the setting of colorectal cancer, for which the role and function of this receptor is poorly defined. More particularly, we will review how the P2Y2 receptor modulates cancer cell proliferation and survival, while promoting cell dissemination and formation of metastases. Finally, we will investigate how the P2Y2 receptor can contribute to the detrimental development of drug resistance that is often observed in cancerous cells.
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Affiliation(s)
- Fernand-Pierre Gendron
- Department of Anatomy and Cell Biology, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée sur le Cancer, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Morgane Placet
- Department of Anatomy and Cell Biology, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée sur le Cancer, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Guillaume Arguin
- Department of Anatomy and Cell Biology, Faculté de Médecine et des Sciences de la Santé, Pavillon de Recherche Appliquée sur le Cancer, Université de Sherbrooke, Sherbrooke, QC, Canada
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12
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Arrestins in the Cardiovascular System: An Update. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2018; 159:27-57. [DOI: 10.1016/bs.pmbts.2018.07.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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13
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Djerada Z, Feliu C, Richard V, Millart H. Current knowledge on the role of P2Y receptors in cardioprotection against ischemia-reperfusion. Pharmacol Res 2016; 118:5-18. [PMID: 27520402 DOI: 10.1016/j.phrs.2016.08.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 08/05/2016] [Accepted: 08/07/2016] [Indexed: 11/27/2022]
Abstract
During ischemia, numerous effective endogenous extracellular mediators have been identified, particularly, nucleosides such as adenosine as well as purinergic and pyrimidinergic nucleotides. They may play important regulatory roles within the cardiovascular system and notably as cardio-protectants. Indeed, the distribution of the P2Y receptors in mammalian heart includes several cellular constituents relevant for the pathophysiology of myocardial ischemia. Beside the well-known cardioprotective effect of adenosine, the additional protective role of P2Y receptors has emerged. However, interpretation of experimental results may be sometimes perplexing. This is due to the variability of: the experimental models, the endpoints criteria, the chemical structure of agonist and antagonist ligands and their concentrations, the sequences of drug administration with respect to the model used (before and/or during and/or after ischemia). The net effect may be in the opposite direction after a transient or a prolonged stimulation. Nevertheless, the overall reading of published data highlights the beneficial role of the P2Y2/4 receptor stimulation, the useful and synergistic role of P2Y6/11 receptor activation and even of the P2Y11 receptor alone in cardioprotection. More, the P2Y11 receptor could be involved in counter-regulation of profibrotic processes. Paradoxically, transient P2X7 receptor stimulation could contribute to the net cardioprotective effect of ATP. Recently, experimental data have shown that blocking the P2Y12 receptor after ischemia confers cardioprotection independently of platelet antiaggregatory effect. This suggests for P2Y receptors an important role in primary prevention and as a therapeutic target in myocardial protection during ischemia and reperfusion.
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Affiliation(s)
- Zoubir Djerada
- Department of Pharmacology, E.A.3801, SFR CAP-santé, Reims University Hospital, 51, rue Cognacq-Jay, 51095 Reims Cedex, France.
| | - Catherine Feliu
- Department of Pharmacology, E.A.3801, SFR CAP-santé, Reims University Hospital, 51, rue Cognacq-Jay, 51095 Reims Cedex, France
| | - Vincent Richard
- Inserm (Institut National de la Santé et de la Recherche Médicale) U1096, Department of Pharmacology, Rouen, France; Normandy University, Institute for Research and Innovation in Biomedicine, Rouen, France
| | - Hervé Millart
- Department of Pharmacology, E.A.3801, SFR CAP-santé, Reims University Hospital, 51, rue Cognacq-Jay, 51095 Reims Cedex, France
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Yang J, Villar VAM, Armando I, Jose PA, Zeng C. G Protein-Coupled Receptor Kinases: Crucial Regulators of Blood Pressure. J Am Heart Assoc 2016; 5:JAHA.116.003519. [PMID: 27390269 PMCID: PMC5015388 DOI: 10.1161/jaha.116.003519] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, China Department of Cardiology, Chongqing Key Laboratory for Hypertension, Chongqing Institute of Cardiology, Chongqing Cardiovascular Clinical Research Center, Daping Hospital, The Third Military Medical University, Chongqing, China
| | - Van Anthony M Villar
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Ines Armando
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Pedro A Jose
- Division of Renal Diseases & Hypertension, Department of Medicine, The George Washington University School of Medicine and Health Sciences, Washington, DC Department of Pharmacology and Physiology, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Chunyu Zeng
- Department of Cardiology, Chongqing Key Laboratory for Hypertension, Chongqing Institute of Cardiology, Chongqing Cardiovascular Clinical Research Center, Daping Hospital, The Third Military Medical University, Chongqing, China
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15
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Epithelial Anion Transport as Modulator of Chemokine Signaling. Mediators Inflamm 2016; 2016:7596531. [PMID: 27382190 PMCID: PMC4921137 DOI: 10.1155/2016/7596531] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 05/03/2016] [Accepted: 05/12/2016] [Indexed: 12/16/2022] Open
Abstract
The pivotal role of epithelial cells is to secrete and absorb ions and water in order to allow the formation of a luminal fluid compartment that is fundamental for the epithelial function as a barrier against environmental factors. Importantly, epithelial cells also take part in the innate immune system. As a first line of defense they detect pathogens and react by secreting and responding to chemokines and cytokines, thus aggravating immune responses or resolving inflammatory states. Loss of epithelial anion transport is well documented in a variety of diseases including cystic fibrosis, chronic obstructive pulmonary disease, asthma, pancreatitis, and cholestatic liver disease. Here we review the effect of aberrant anion secretion with focus on the release of inflammatory mediators by epithelial cells and discuss putative mechanisms linking these transport defects to the augmented epithelial release of chemokines and cytokines. These mechanisms may contribute to the excessive and persistent inflammation in many respiratory and gastrointestinal diseases.
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Srivastava A, Gupta B, Gupta C, Shukla AK. Emerging Functional Divergence of β-Arrestin Isoforms in GPCR Function. Trends Endocrinol Metab 2015; 26:628-642. [PMID: 26471844 DOI: 10.1016/j.tem.2015.09.001] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 08/21/2015] [Accepted: 09/02/2015] [Indexed: 12/22/2022]
Abstract
G protein-coupled receptors (GPCRs) are tightly regulated by multifunctional protein β-arrestins. Two isoforms of β-arrestin sharing more than 70% sequence identity and overall very similar 3D structures, β-arrestins 1 and 2, were originally expected to be functionally redundant. However, in recent years multiple lines of emerging evidence suggest they have distinct roles in various aspects of GPCR regulation and signaling. We summarize selected examples of GPCRs where β-arrestin isoforms are discovered to display non-overlapping and sometimes even antagonistic functions. We also discuss potential mechanistic basis for their functional divergence and highlight new frontiers that are likely to form the focal points of research in this area in coming years.
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Affiliation(s)
- Ashish Srivastava
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Bhagyashri Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Charu Gupta
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India
| | - Arun K Shukla
- Department of Biological Sciences and Bioengineering, Indian Institute of Technology, Kanpur 208016, India.
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Willets JM, Nash CA, Rainbow RD, Nelson CP, Challiss RAJ. Defining the roles of arrestin2 and arrestin3 in vasoconstrictor receptor desensitization in hypertension. Am J Physiol Cell Physiol 2015; 309:C179-89. [PMID: 25972452 PMCID: PMC4525080 DOI: 10.1152/ajpcell.00079.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/11/2015] [Indexed: 11/22/2022]
Abstract
Prolonged vasoconstrictor-stimulated phospholipase C activity can induce arterial constriction, hypertension, and smooth muscle hypertrophy/hyperplasia. Arrestin proteins are recruited by agonist-occupied G protein-coupled receptors to terminate signaling and counteract changes in vascular tone. Here we determine whether the development of hypertension affects arrestin expression in resistance arteries and how such changes alter arterial contractile signaling and function. Arrestin2/3 expression was increased in mesenteric arteries of 12-wk-old spontaneously hypertensive rats (SHR) compared with normotensive Wistar-Kyoto (WKY) controls, while no differences in arrestin expression were observed between 6-wk-old SHR and WKY animals. In mesenteric artery myography experiments, high extracellular K(+)-stimulated contractions were increased in both 6- and 12-wk-old SHR animals. Concentration-response experiments for uridine 5'-triphosphate (UTP) acting through P2Y receptors displayed a leftward shift in 12-wk, but not 6-wk-old animals. Desensitization of UTP-stimulated vessel contractions was increased in 12-wk-old (but not 6-wk-old) SHR animals. Dual IP3/Ca(2+) imaging in mesenteric arterial cells showed that desensitization of UTP and endothelin-1 (ET1) responses was enhanced in 12-wk-old (but not 6-wk-old) SHR compared with WKY rats. siRNA-mediated depletion of arrestin2 for UTP and arrestin3 for ET1, reversed the desensitization of PLC signaling. In conclusion, arrestin2 and 3 expression is elevated in resistance arteries during the emergence of the early hypertensive phenotype, which underlies an enhanced ability to desensitize vasoconstrictor signaling and vessel contraction. Such regulatory changes may act to compensate for increased vasoconstrictor-induced vessel contraction.
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Affiliation(s)
- Jonathon M Willets
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
| | - Craig A Nash
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
| | - Richard D Rainbow
- Department of Cardiovascular Sciences, University of Leicester, Glenfield General Hospital, Leicester, United Kingdom
| | - Carl P Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
| | - R A John Challiss
- Department of Cell Physiology and Pharmacology, University of Leicester, Leicester, United Kingdom; and
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18
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Melanopsin mediates light-dependent relaxation in blood vessels. Proc Natl Acad Sci U S A 2014; 111:17977-82. [PMID: 25404319 DOI: 10.1073/pnas.1420258111] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Melanopsin (opsin4; Opn4), a non-image-forming opsin, has been linked to a number of behavioral responses to light, including circadian photo-entrainment, light suppression of activity in nocturnal animals, and alertness in diurnal animals. We report a physiological role for Opn4 in regulating blood vessel function, particularly in the context of photorelaxation. Using PCR, we demonstrate that Opn4 (a classic G protein-coupled receptor) is expressed in blood vessels. Force-tension myography demonstrates that vessels from Opn4(-/-) mice fail to display photorelaxation, which is also inhibited by an Opn4-specific small-molecule inhibitor. The vasorelaxation is wavelength-specific, with a maximal response at ∼430-460 nm. Photorelaxation does not involve endothelial-, nitric oxide-, carbon monoxide-, or cytochrome p450-derived vasoactive prostanoid signaling but is associated with vascular hyperpolarization, as shown by intracellular membrane potential measurements. Signaling is both soluble guanylyl cyclase- and phosphodiesterase 6-dependent but protein kinase G-independent. β-Adrenergic receptor kinase 1 (βARK 1 or GRK2) mediates desensitization of photorelaxation, which is greatly reduced by GRK2 inhibitors. Blue light (455 nM) regulates tail artery vasoreactivity ex vivo and tail blood blood flow in vivo, supporting a potential physiological role for this signaling system. This endogenous opsin-mediated, light-activated molecular switch for vasorelaxation might be harnessed for therapy in diseases in which altered vasoreactivity is a significant pathophysiologic contributor.
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19
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Morris GE, Bridge JC, Eltboli OMI, Lewis MP, Knox AJ, Aylott JW, Brightling CE, Ghaemmaghami AM, Rose FRAJ. Human airway smooth muscle maintain in situ cell orientation and phenotype when cultured on aligned electrospun scaffolds. Am J Physiol Lung Cell Mol Physiol 2014; 307:L38-47. [PMID: 24793171 PMCID: PMC4080283 DOI: 10.1152/ajplung.00318.2013] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 05/01/2014] [Indexed: 11/22/2022] Open
Abstract
Human airway smooth muscle (HASM) contraction plays a central role in regulating airway resistance in both healthy and asthmatic bronchioles. In vitro studies that investigate the intricate mechanisms that regulate this contractile process are predominantly conducted on tissue culture plastic, a rigid, 2D geometry, unlike the 3D microenvironment smooth muscle cells are exposed to in situ. It is increasingly apparent that cellular characteristics and responses are altered between cells cultured on 2D substrates compared with 3D topographies. Electrospinning is an attractive method to produce 3D topographies for cell culturing as the fibers produced have dimensions within the nanometer range, similar to cells' natural environment. We have developed an electrospun scaffold using the nondegradable, nontoxic, polymer polyethylene terephthalate (PET) composed of uniaxially orientated nanofibers and have evaluated this topography's effect on HASM cell adhesion, alignment, and morphology. The fibers orientation provided contact guidance enabling the formation of fully aligned sheets of smooth muscle. Moreover, smooth muscle cells cultured on the scaffold present an elongated cell phenotype with altered contractile protein levels and distribution. HASM cells cultured on this scaffold responded to the bronchoconstrictor bradykinin. The platform presented provides a novel in vitro model that promotes airway smooth muscle cell development toward a more in vivo-like phenotype while providing topological cues to ensure full cell alignment.
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Affiliation(s)
- G E Morris
- Division of Drug Delivery and Tissue Engineering, Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
| | - J C Bridge
- Division of Drug Delivery and Tissue Engineering, Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
| | - O M I Eltboli
- NIHR Respiratory Biomedical Research Unit, University of Leicester, Leicester, United Kingdom
| | | | - A J Knox
- Division of Respiratory Medicine, School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - J W Aylott
- Laboratory of Biophysics and Surface Analysis, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom; and
| | - C E Brightling
- NIHR Respiratory Biomedical Research Unit, University of Leicester, Leicester, United Kingdom
| | - A M Ghaemmaghami
- Division of Immunology, School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - F R A J Rose
- Division of Drug Delivery and Tissue Engineering, Centre for Biomolecular Sciences, School of Pharmacy, University of Nottingham, Nottingham, United Kingdom;
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Clift IC, Bamidele AO, Rodriguez-Ramirez C, Kremer KN, Hedin KE. β-Arrestin1 and distinct CXCR4 structures are required for stromal derived factor-1 to downregulate CXCR4 cell-surface levels in neuroblastoma. Mol Pharmacol 2014; 85:542-52. [PMID: 24452472 DOI: 10.1124/mol.113.089714] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
CXC chemokine receptor 4 (CXCR4) is a G protein-coupled receptor (GPCR) located on the cell surface that signals upon binding the chemokine stromal derived factor-1 (SDF-1; also called CXCL 12). CXCR4 promotes neuroblastoma proliferation and chemotaxis. CXCR4 expression negatively correlates with prognosis and drives neuroblastoma growth and metastasis in mouse models. All functions of CXCR4 require its expression on the cell surface, yet the molecular mechanisms that regulate CXCR4 cell-surface levels in neuroblastoma are poorly understood. We characterized CXCR4 cell-surface regulation in the related SH-SY5Y and SK-N-SH human neuroblastoma cell lines. SDF-1 treatment caused rapid down-modulation of CXCR4 in SH-SY5Y cells. Pharmacologic activation of protein kinase C similarly reduced CXCR4, but via a distinct mechanism. Analysis of CXCR4 mutants delineated two CXCR4 regions required for SDF-1 treatment to decrease cell-surface CXCR4 in neuroblastoma cells: the isoleucine-leucine motif at residues 328 and 329 and residues 343-352. In contrast, and unlike CXCR4 regulation in other cell types, serines 324, 325, 338, and 339 were not required. Arrestin proteins can bind and regulate GPCR cell-surface expression, often functioning together with kinases such as G protein-coupled receptor kinase 2 (GRK2). Using SK-N-SH cells which are naturally deficient in β-arrestin1, we showed that β-arrestin1 is required for the CXCR4 343-352 region to modulate CXCR4 cell-surface expression following treatment with SDF-1. Moreover, GRK2 overexpression enhanced CXCR4 internalization, via a mechanism requiring both β-arrestin1 expression and the 343-352 region. Together, these results characterize CXCR4 structural domains and β-arrestin1 as critical regulators of CXCR4 cell-surface expression in neuroblastoma. β-Arrestin1 levels may therefore influence the CXCR4-driven metastasis of neuroblastoma as well as prognosis.
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Affiliation(s)
- Ian C Clift
- Neurobiology of Disease (I.C.C.), Molecular Pharmacology and Experimental Therapeutics (A.O.B.), and Department of Immunology (C.R.-R., K.N.K., K.E.H.), Mayo Clinic College of Medicine, Mayo Graduate School, Mayo Clinic, Rochester, Minnesota
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Lu D, Insel PA. Cellular mechanisms of tissue fibrosis. 6. Purinergic signaling and response in fibroblasts and tissue fibrosis. Am J Physiol Cell Physiol 2013; 306:C779-88. [PMID: 24352335 DOI: 10.1152/ajpcell.00381.2013] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Tissue fibrosis occurs as a result of the dysregulation of extracellular matrix (ECM) synthesis. Tissue fibroblasts, resident cells responsible for the synthesis and turnover of ECM, are regulated via numerous hormonal and mechanical signals. The release of intracellular nucleotides and their resultant autocrine/paracrine signaling have been shown to play key roles in the homeostatic maintenance of tissue remodeling and in fibrotic response post-injury. Extracellular nucleotides signal through P2 nucleotide and P1 adenosine receptors to activate signaling networks that regulate the proliferation and activity of fibroblasts, which, in turn, influence tissue structure and pathologic remodeling. An important component in the signaling and functional responses of fibroblasts to extracellular ATP and adenosine is the expression and activity of ectonucleotideases that attenuate nucleotide-mediated signaling, and thereby integrate P2 receptor- and subsequent adenosine receptor-initiated responses. Results of studies of the mechanisms of cellular nucleotide release and the effects of this autocrine/paracrine signaling axis on fibroblast-to-myofibroblast conversion and the fibrotic phenotype have advanced understanding of tissue remodeling and fibrosis. This review summarizes recent findings related to purinergic signaling in the regulation of fibroblasts and the development of tissue fibrosis in the heart, lungs, liver, and kidney.
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Affiliation(s)
- David Lu
- Department of Pharmacology, University of California, San Diego, La Jolla, California; and
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22
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Burnstock G, Ralevic V. Purinergic signaling and blood vessels in health and disease. Pharmacol Rev 2013; 66:102-92. [PMID: 24335194 DOI: 10.1124/pr.113.008029] [Citation(s) in RCA: 219] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Purinergic signaling plays important roles in control of vascular tone and remodeling. There is dual control of vascular tone by ATP released as a cotransmitter with noradrenaline from perivascular sympathetic nerves to cause vasoconstriction via P2X1 receptors, whereas ATP released from endothelial cells in response to changes in blood flow (producing shear stress) or hypoxia acts on P2X and P2Y receptors on endothelial cells to produce nitric oxide and endothelium-derived hyperpolarizing factor, which dilates vessels. ATP is also released from sensory-motor nerves during antidromic reflex activity to produce relaxation of some blood vessels. In this review, we stress the differences in neural and endothelial factors in purinergic control of different blood vessels. The long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides in promoting migration and proliferation of both vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis and vessel remodeling during restenosis after angioplasty are described. The pathophysiology of blood vessels and therapeutic potential of purinergic agents in diseases, including hypertension, atherosclerosis, ischemia, thrombosis and stroke, diabetes, and migraine, is discussed.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London NW3 2PF, UK; and Department of Pharmacology, The University of Melbourne, Australia.
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Xie DP, Li S, Li L, Chang XW, Xi TF, Yang X, Jin Z, Zeng Y. Beta-arrestin2 is involved in the increase of distal colonic contraction in diabetic rats. ACTA ACUST UNITED AC 2013; 185:29-33. [PMID: 23816471 DOI: 10.1016/j.regpep.2013.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 03/07/2013] [Accepted: 06/19/2013] [Indexed: 12/26/2022]
Abstract
Colonic dysmotility occurs in diabetes and the patients exhibit diarrhea or constipation. The pathogenetic mechanisms underlying colonic dysmotility in diabetic patients remain poorly understood. The effects of β-arrestin2 on colonic contraction in diabetic rats were investigated for the first time. Male SD rats were treated with a single intraperitoneally injected dose of streptozotocin, and those displaying sustained high blood glucose were selected as diabetes mellitus models. Longitudinal muscle strips of the distal colon were prepared to monitor contraction of the colon in vitro. Expression of β-arrestin2 was investigated by Western blot analysis. Anti-β-arrestin2 antibody had no direct effect on the contraction of distal colonic strips in both normal and diabetic rats. Carbachol-induced contractions of distal colonic strips were higher in diabetic rats than in normal rats. Anti-β-arrestin2 antibody partly blocked carbachol-induced increases of distal colonic strips in diabetic rats. The expression level of β-arrestin2 protein in the colon was higher in diabetic rats than in normal rats. These results suggest that β-arrestin2 is involved in the increase of distal colonic contraction in diabetic rats.
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Affiliation(s)
- Dong-Ping Xie
- Department of Physiology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai 200092, PR China.
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Zhao J, Pei G. Arrestins in metabolic regulation. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 118:413-27. [PMID: 23764063 DOI: 10.1016/b978-0-12-394440-5.00016-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This review summarizes the regulatory roles of β-arrestins in whole-body energy balance, body weight control, and carbohydrate and lipid homeostasis. Much research has pointed in the direction of the functions of β-arrestins in mediating desensitization and endocytosis of G protein-coupled receptors as well as in activating the receptor/β-arrestin/ERK signaling pathway being crucial for metabolic regulation. Furthermore, β-arrestins form diverse signal complexes for the activation of the downstream cassettes for the body's metabolic reactions. However, further studies are required to fully address the emerging roles of β-arrestins in metabolic regulation and related diseases.
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Affiliation(s)
- Jian Zhao
- State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, PR China
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Arrestins in the cardiovascular system. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 118:297-334. [PMID: 23764059 DOI: 10.1016/b978-0-12-394440-5.00012-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Of the four mammalian arrestins, only the β-arrestins (βarrs; Arrestin2 and -3) are expressed throughout the cardiovascular system, where they regulate, as either desensitizers/internalizers or signal transducers, several G-protein-coupled receptors (GPCRs) critical for cardiovascular homeostasis. The cardiovascular roles of βarrs have been delineated at an accelerated pace via a variety of techniques and tools, such as knockout mice, siRNA knockdown, artificial or naturally occurring polymorphic GPCRs, and availability of new βarr "biased" GPCR ligands. This chapter summarizes the current knowledge of cardiovascular arrestin physiology and pharmacology, addressing the individual cardiovascular receptors affected by βarrs in vivo, as well as the individual cell types, tissues, and organs of the cardiovascular system in which βarr effects are exerted; for example, cardiac myocyte or fibroblast, vascular smooth muscle, adrenal gland and platelet. In the broader scope of cardiovascular βarr pharmacology, a discussion of the βarr "bias" of certain cardiovascular GPCR ligands is also included.
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Le Sommer C, Barrows NJ, Bradrick SS, Pearson JL, Garcia-Blanco MA. G protein-coupled receptor kinase 2 promotes flaviviridae entry and replication. PLoS Negl Trop Dis 2012; 6:e1820. [PMID: 23029581 PMCID: PMC3441407 DOI: 10.1371/journal.pntd.0001820] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 08/03/2012] [Indexed: 11/17/2022] Open
Abstract
Flaviviruses cause a wide range of severe diseases ranging from encephalitis to hemorrhagic fever. Discovery of host factors that regulate the fate of flaviviruses in infected cells could provide insight into the molecular mechanisms of infection and therefore facilitate the development of anti-flaviviral drugs. We performed genome-scale siRNA screens to discover human host factors required for yellow fever virus (YFV) propagation. Using a 2×2 siRNA pool screening format and a duplicate of the screen, we identified a high confidence list of YFV host factors. To find commonalities between flaviviruses, these candidates were compared to host factors previously identified for West Nile virus (WNV) and dengue virus (DENV). This comparison highlighted a potential requirement for the G protein-coupled receptor kinase family, GRKs, for flaviviral infection. The YFV host candidate GRK2 (also known as ADRBK1) was validated both in siRNA-mediated knockdown HuH-7 cells and in GRK−/− mouse embryonic fibroblasts. Additionally, we showed that GRK2 was required for efficient propagation of DENV and Hepatitis C virus (HCV) indicating that GRK2 requirement is conserved throughout the Flaviviridae. Finally, we found that GRK2 participates in multiple distinct steps of the flavivirus life cycle by promoting both entry and RNA synthesis. Together, our findings identified GRK2 as a novel regulator of flavivirus infection and suggest that inhibition of GRK2 function may constitute a new approach for treatment of flavivirus associated diseases. The Flavivirus genus includes several emergent and reemergent viruses, such as dengue and yellow fever viruses, which cause severe diseases in humans for which there is no approved treatment. Flaviviruses are transmitted to humans by arthropods and they rely on scores of vertebrate and invertebrate factors to replicate in these disparate hosts. Identifying the host factors involved in viral propagation is critical to understanding the molecular mechanisms of infection and the development of new therapeutics. To identify human host factors required for yellow fever virus propagation, we completed two genome-scale siRNA screens. Among the candidates discovered were the G protein-coupled receptor kinases GRK2 and GRK4. We focused on the protein GRK2, a kinase first identified for its role in cellular signal transduction. We found that GRK2 was a host factor needed for productive infection by yellow fever, dengue and hepatitis C viruses and was required for both viral entry and efficient replication of the viral genome. GRKs, which are considered druggable, may be used as targets to develop broadspectrum anti-flavivirals.
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Affiliation(s)
- Caroline Le Sommer
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America
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Veit G, Bossard F, Goepp J, Verkman AS, Galietta LJV, Hanrahan JW, Lukacs GL. Proinflammatory cytokine secretion is suppressed by TMEM16A or CFTR channel activity in human cystic fibrosis bronchial epithelia. Mol Biol Cell 2012; 23:4188-202. [PMID: 22973054 PMCID: PMC3484098 DOI: 10.1091/mbc.e12-06-0424] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Functional expression of either CFTR or the calcium-activated chloride channel TMEM16A attenuates expression and secretion of the proinflammatory cytokines IL-6, IL-8, and CXCL1/2 in respiratory epithelia. Thus augmented proinflammatory cytokine secretion caused by defective anion transport may contribute to lung inflammation in cystic fibrosis. Cystic fibrosis (CF) is caused by the functional expression defect of the CF transmembrane conductance regulator (CFTR) chloride channel at the apical plasma membrane. Impaired bacterial clearance and hyperactive innate immune response are hallmarks of the CF lung disease, yet the existence of and mechanism accounting for the innate immune defect that occurs before infection remain controversial. Inducible expression of either CFTR or the calcium-activated chloride channel TMEM16A attenuated the proinflammatory cytokines interleukin-6 (IL-6), IL-8, and CXCL1/2 in two human respiratory epithelial models under air–liquid but not liquid–liquid interface culture. Expression of wild-type but not the inactive G551D-CFTR indicates that secretion of the chemoattractant IL-8 is inversely proportional to CFTR channel activity in cftr∆F508/∆F508 immortalized and primary human bronchial epithelia. Similarly, direct but not P2Y receptor–mediated activation of TMEM16A attenuates IL-8 secretion in respiratory epithelia. Thus augmented proinflammatory cytokine secretion caused by defective anion transport at the apical membrane may contribute to the excessive and persistent lung inflammation in CF and perhaps in other respiratory diseases associated with documented down-regulation of CFTR (e.g., chronic obstructive pulmonary disease). Direct pharmacological activation of TMEM16A offers a potential therapeutic strategy to reduce the inflammation of CF airway epithelia.
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Affiliation(s)
- Guido Veit
- Department of Physiology and Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montréal, QC H3G 1Y6, Canada
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Erb L, Weisman GA. Coupling of P2Y receptors to G proteins and other signaling pathways. ACTA ACUST UNITED AC 2012; 1:789-803. [PMID: 25774333 DOI: 10.1002/wmts.62] [Citation(s) in RCA: 135] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
P2Y receptors are G protein-coupled receptors (GPCRs) that are activated by adenine and uridine nucleotides and nucleotide sugars. There are eight subtypes of P2Y receptors (P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, P2Y12, P2Y13, and P2Y14), which activate intracellular signaling cascades to regulate a variety of cellular processes, including proliferation, differentiation, phagocytosis, secretion, nociception, cell adhesion, and cell migration. These signaling cascades operate mainly by the sequential activation or deactivation of heterotrimeric and monomeric G proteins, phospholipases, adenylyl and guanylyl cyclases, protein kinases, and phosphodiesterases. In addition, there are numerous ion channels, cell adhesion molecules, and receptor tyrosine kinases that are modulated by P2Y receptors and operate to transmit an extracellular signal to an intracellular response.
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Affiliation(s)
- Laurie Erb
- Department of Biochemistry, Life Sciences Center, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - Gary A Weisman
- Department of Biochemistry, Life Sciences Center, University of Missouri-Columbia, Columbia, MO 65211, USA
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Morris GE, Nelson CP, Brighton PJ, Standen NB, Challiss RAJ, Willets JM. Arrestins 2 and 3 differentially regulate ETA and P2Y2 receptor-mediated cell signaling and migration in arterial smooth muscle. Am J Physiol Cell Physiol 2011; 302:C723-34. [PMID: 22159081 DOI: 10.1152/ajpcell.00202.2011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Overstimulation of endothelin type A (ET(A)) and nucleotide (P2Y) Gα(q)-coupled receptors in vascular smooth muscle causes vasoconstriction, hypertension, and, eventually, hypertrophy and vascular occlusion. G protein-coupled receptor kinases (GRKs) and arrestin proteins are sequentially recruited by agonist-occupied Gα(q)-coupled receptors to terminate phospholipase C signaling, preventing prolonged/inappropriate contractile signaling. However, these proteins also play roles in the regulation of several mitogen-activated protein kinase (MAPK) signaling cascades known to be essential for vascular remodeling. Here we investigated whether different arrestin isoforms regulate endothelin and nucleotide receptor MAPK signaling in rat aortic smooth muscle cells (ASMCs). When intracellular Ca(2+) levels were assessed in isolated ASMCs loaded with Ca(2+)-sensitive dyes, P2Y(2) and ET(A) receptor desensitization was attenuated by selective small-interfering (si)RNA-mediated depletion of G protein-coupled receptor kinase 2 (GRK2). Using similar siRNA techniques, knockdown of arrestin2 prevented P2Y(2) receptor desensitization and enhanced and prolonged p38 and ERK MAPK signals, while arrestin3 depletion was ineffective. Conversely, arrestin3 knockdown prevented ET(A) receptor desensitization and attenuated ET1-stimulated p38 and ERK signals, while arrestin2 depletion had no effect. Using Transwell assays to assess agonist-stimulated ASMC migration, we found that UTP-stimulated migration was markedly attenuated following arrestin2 depletion, while ET1-stimulated migration was attenuated following knockdown of either arrestin. These data highlight a differential arrestin-dependent regulation of ET(A) and P2Y(2) receptor-stimulated MAPK signaling. GRK2 and arrestin expression are essential for agonist-stimulated ASMC migration, which, as a key process in vascular remodeling, highlights the potential roles of GRK2 and arrestin proteins in the progression of vascular disease.
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Affiliation(s)
- Gavin E Morris
- Dept. of Cancer Studies and Molecular Medicine, Leicester Royal Infirmary, Leicester, UK
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Nelson CP, Rainbow RD, Brignell JL, Perry MD, Willets JM, Davies NW, Standen NB, Challiss RJ. Principal role of adenylyl cyclase 6 in K⁺ channel regulation and vasodilator signalling in vascular smooth muscle cells. Cardiovasc Res 2011; 91:694-702. [PMID: 21606183 PMCID: PMC3156907 DOI: 10.1093/cvr/cvr137] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 05/06/2011] [Accepted: 05/12/2011] [Indexed: 02/07/2023] Open
Abstract
AIMS Membrane potential is a key determinant of vascular tone and many vasodilators act through the modulation of ion channel currents [e.g. the ATP-sensitive potassium channel (K(ATP))] involved in setting the membrane potential. Adenylyl cyclase (AC) isoenzymes are potentially important intermediaries in such vasodilator signalling pathways. Vascular smooth muscle cells (VSMCs) express multiple AC isoenzymes, but the reason for such redundancy is unknown. We investigated which of these isoenzymes are involved in vasodilator signalling and regulation of vascular ion channels important in modulating membrane potential. METHODS AND RESULTS AC isoenzymes were selectively depleted (by >75%) by transfection of cultured VSMCs with selective short interfering RNA sequences. AC6 was the predominant isoenzyme involved in vasodilator-mediated cAMP accumulation in VSMCs, accounting for ∼60% of the total response to β-adrenoceptor (β-AR) stimulation. AC3 played a minor role in β-AR signalling, whereas AC5 made no significant contribution. AC6 was also the principal isoenzyme involved in β-AR-mediated protein kinase A (PKA) signalling (determined using the fluorescent biosensor for PKA activity, AKAR3) and the substantial β-AR/PKA-dependent enhancement of K(ATP) current. K(ATP) current was shown to play a vital role in setting the resting membrane potential and in mediating the hyperpolarization observed upon β-AR stimulation. CONCLUSION AC6, but not the closely related AC5, plays a principal role in vasodilator signalling and regulation of the membrane potential in VSMCs. These findings identify AC6 as a vital component in the vasodilatory apparatus central to the control of blood pressure.
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Affiliation(s)
- Carl P. Nelson
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Richard D. Rainbow
- Department of Cardiovascular Sciences, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK
| | - Jennifer L. Brignell
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Matthew D. Perry
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Jonathon M. Willets
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
- Department of Cancer Studies and Molecular Medicine, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, Leicester LE2 7LX, UK
| | - Noel W. Davies
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - Nicholas B. Standen
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
| | - R.A. John Challiss
- Department of Cell Physiology and Pharmacology, University of Leicester, Henry Wellcome Building, Lancaster Road, Leicester LE1 9HN, UK
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Whalen EJ, Rajagopal S, Lefkowitz RJ. Therapeutic potential of β-arrestin- and G protein-biased agonists. Trends Mol Med 2010; 17:126-39. [PMID: 21183406 DOI: 10.1016/j.molmed.2010.11.004] [Citation(s) in RCA: 418] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 11/13/2010] [Accepted: 11/17/2010] [Indexed: 12/21/2022]
Abstract
Members of the seven-transmembrane receptor (7TMR), or G protein-coupled receptor (GPCR), superfamily represent some of the most successful targets of modern drug therapy, with proven efficacy in the treatment of a broad range of human conditions and disease processes. It is now appreciated that β-arrestins, once viewed simply as negative regulators of traditional 7TMR-stimulated G protein signaling, act as multifunctional adapter proteins that regulate 7TMR desensitization and trafficking and promote distinct intracellular signals in their own right. Moreover, several 7TMR biased agonists, which selectively activate these divergent signaling pathways, have been identified. Here we highlight the diversity of G protein- and β-arrestin-mediated functions and the therapeutic potential of selective targeting of these in disease states.
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Affiliation(s)
- Erin J Whalen
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
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Shi G, Morrell CN. Platelets as initiators and mediators of inflammation at the vessel wall. Thromb Res 2010; 127:387-90. [PMID: 21094986 DOI: 10.1016/j.thromres.2010.10.019] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 10/15/2010] [Accepted: 10/17/2010] [Indexed: 01/16/2023]
Abstract
Platelets are dynamic cells with activities that extend beyond thrombosis including an important role in initiating and sustaining vascular inflammation. A role for platelets has been described in many physiologic and pathophysiologic processes such as atherosclerosis, stem cell trafficking, tumor metastasis, and arthritis. Platelet activation at sites of an intact inflamed endothelium contributes to vascular inflammation and vascular wall remodeling. Platelets secrete a wide array of preformed and synthesized inflammatory mediators upon activation that can exert significant local and systemic effects. This review will focus on the role of platelet derived mediators in vascular inflammation and vascular wall remodeling.
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Affiliation(s)
- Guanfang Shi
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine & Dentistry, 601 Elmwood Avenue, Box CVRI, Rochester, New York 14642, USA
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