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Bono F, Fiorentini C, Mutti V, Tomasoni Z, Sbrini G, Trebesova H, Marchi M, Grilli M, Missale C. Central nervous system interaction and crosstalk between nAChRs and other ionotropic and metabotropic neurotransmitter receptors. Pharmacol Res 2023; 190:106711. [PMID: 36854367 DOI: 10.1016/j.phrs.2023.106711] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/20/2023] [Accepted: 02/24/2023] [Indexed: 02/27/2023]
Abstract
Neuronal nicotinic acetylcholine receptors (nAChRs) are widely distributed in both the peripheral and the central nervous systems. nAChRs exert a crucial modulatory influence on several brain biological processes; they are involved in a variety of neuronal diseases including Parkinson's disease, Alzheimer's disease, epilepsy, and nicotine addiction. The influence of nAChRs on brain function depends on the activity of other neurotransmitter receptors that co-exist with nAChRs on neurons. In fact, the crosstalk between receptors is an important mechanism of neurotransmission modulation and plasticity. This may be due to converging intracellular pathways but also occurs at the membrane level, because of direct physical interactions between receptors. In this line, this review is dedicated to summarizing how nAChRs and other ionotropic and metabotropic receptors interact and the relevance of nAChRs cross-talks in modulating various neuronal processes ranging from the classical modulation of neurotransmitter release to neuron plasticity and neuroprotection.
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Affiliation(s)
- Federica Bono
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Chiara Fiorentini
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Veronica Mutti
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Zaira Tomasoni
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Giulia Sbrini
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
| | - Hanna Trebesova
- Department of Pharmacy, University of Genova, 16148 Genoa, Italy
| | - Mario Marchi
- Department of Pharmacy, University of Genova, 16148 Genoa, Italy
| | - Massimo Grilli
- Department of Pharmacy, University of Genova, 16148 Genoa, Italy.
| | - Cristina Missale
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy
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The role of PGE2 and EP receptors on lung's immune and structural cells; possibilities for future asthma therapy. Pharmacol Ther 2023; 241:108313. [PMID: 36427569 DOI: 10.1016/j.pharmthera.2022.108313] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 10/06/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022]
Abstract
Asthma is the most common airway chronic disease with treatments aimed mainly to control the symptoms. Adrenergic receptor agonists, corticosteroids and anti-leukotrienes have been used for decades, and the development of more targeted asthma treatments, known as biological therapies, were only recently established. However, due to the complexity of asthma and the limited efficacy as well as the side effects of available treatments, there is an urgent need for a new generation of asthma therapies. The anti-inflammatory and bronchodilatory effects of prostaglandin E2 in asthma are promising, yet complicated by undesirable side effects, such as cough and airway irritation. In this review, we summarize the most important literature on the role of all four E prostanoid (EP) receptors on the lung's immune and structural cells to further dissect the relevance of EP2/EP4 receptors as potential targets for future asthma therapy.
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Kühnen P, Biebermann H, Wiegand S. Pharmacotherapy in Childhood Obesity. Horm Res Paediatr 2022; 95:177-192. [PMID: 34351307 DOI: 10.1159/000518432] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 07/12/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The increasing number of obese children and adolescence is a major problem in health-care systems. Currently, the gold standard for the treatment of these patients with obesity is a multicomponent lifestyle intervention. Unfortunately, this strategy is not leading to a substantial and long-lasting weight loss in the majority of patients. This is the reason why there is an urgent need to establish new treatment strategies for children and adolescents with obesity to reduce the risk for the development of any comorbidities like cardiovascular diseases or diabetes mellitus type 2. SUMMARY In this review, we outline available pharmacological therapeutic options for children and compare the available study data with the outcome of conservative treatment approaches. KEY MESSAGES We discussed, in detail, how knowledge about underlying molecular mechanisms might support the identification of effective antiobesity drugs in the future and in which way this might modulate current treatment strategies to support children and adolescence with obesity to lose body weight.
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Affiliation(s)
- Peter Kühnen
- Institute for Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Heike Biebermann
- Institute for Experimental Pediatric Endocrinology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
| | - Susanna Wiegand
- Center for Social-Pediatric Care/Pediatric Endocrinology and Diabetology, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin Institute of Health, Berlin, Germany
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Bryson TD, Harding P. Prostaglandin E2 EP receptors in cardiovascular disease: An update. Biochem Pharmacol 2021; 195:114858. [PMID: 34822808 DOI: 10.1016/j.bcp.2021.114858] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 12/20/2022]
Abstract
This review article provides an update for the role of prostaglandin E2 receptors (EP1, EP2, EP3 and EP4) in cardiovascular disease. Where possible we have reported citations from the last decade although this was not possible for all of the topics covered due to the paucity of publications. The authors have attempted to cover the subjects of ischemia-reperfusion injury, arrhythmias, hypertension, novel protein binding partners of the EP receptors and their pathophysiological significance, and cardiac regeneration. These latter two topics bring studies of the EP receptors into new and exciting areas of research that are just beginning to be explored. Where there is peer-reviewed literature, the authors have placed particular emphasis on clinical studies although these are limited in number.
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Affiliation(s)
- Timothy D Bryson
- Department of Emergency Medicine, University of Michigan Medical School, Ann Arbor, MI, United States; Frankel Cardiovascular Center, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Pamela Harding
- Hypertension & Vascular Research Division, Department of Internal Medicine, Henry Ford Health System, Detroit, MI, United States; Department of Physiology, Wayne State University School of Medicine, Detroit, MI, United States.
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Eicosanoid receptors as therapeutic targets for asthma. Clin Sci (Lond) 2021; 135:1945-1980. [PMID: 34401905 DOI: 10.1042/cs20190657] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 07/23/2021] [Accepted: 08/03/2021] [Indexed: 12/16/2022]
Abstract
Eicosanoids comprise a group of oxidation products of arachidonic and 5,8,11,14,17-eicosapentaenoic acids formed by oxygenases and downstream enzymes. The two major pathways for eicosanoid formation are initiated by the actions of 5-lipoxygenase (5-LO), leading to leukotrienes (LTs) and 5-oxo-6,8,11,14-eicosatetraenoic acid (5-oxo-ETE), and cyclooxygenase (COX), leading to prostaglandins (PGs) and thromboxane (TX). A third group (specialized pro-resolving mediators; SPMs), including lipoxin A4 (LXA4) and resolvins (Rvs), are formed by the combined actions of different oxygenases. The actions of the above eicosanoids are mediated by approximately 20 G protein-coupled receptors, resulting in a variety of both detrimental and beneficial effects on airway smooth muscle and inflammatory cells that are strongly implicated in asthma pathophysiology. Drugs targeting proinflammatory eicosanoid receptors, including CysLT1, the receptor for LTD4 (montelukast) and TP, the receptor for TXA2 (seratrodast) are currently in use, whereas antagonists of a number of other receptors, including DP2 (PGD2), BLT1 (LTB4), and OXE (5-oxo-ETE) are under investigation. Agonists targeting anti-inflammatory/pro-resolving eicosanoid receptors such as EP2/4 (PGE2), IP (PGI2), ALX/FPR2 (LXA4), and Chemerin1 (RvE1/2) are also being examined. This review summarizes the contributions of eicosanoid receptors to the pathophysiology of asthma and the potential therapeutic benefits of drugs that target these receptors. Because of the multifactorial nature of asthma and the diverse pathways affected by eicosanoid receptors, it will be important to identify subgroups of asthmatics that are likely to respond to any given therapy.
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Biringer RG. A Review of Prostanoid Receptors: Expression, Characterization, Regulation, and Mechanism of Action. J Cell Commun Signal 2021; 15:155-184. [PMID: 32970276 PMCID: PMC7991060 DOI: 10.1007/s12079-020-00585-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 09/15/2020] [Indexed: 12/22/2022] Open
Abstract
Prostaglandin signaling controls a wide range of biological processes from blood pressure homeostasis to inflammation and resolution thereof to the perception of pain to cell survival. Disruption of normal prostanoid signaling is implicated in numerous disease states. Prostaglandin signaling is facilitated by G-protein-coupled, prostanoid-specific receptors and the array of associated G-proteins. This review focuses on the expression, characterization, regulation, and mechanism of action of prostanoid receptors with particular emphasis on human isoforms.
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Affiliation(s)
- Roger G Biringer
- College of Osteopathic Medicine, Lake Erie College of Osteopathic Medicine, 5000 Lakewood Ranch Blvd, Bradenton, FL, 34211, USA.
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Norel X, Sugimoto Y, Ozen G, Abdelazeem H, Amgoud Y, Bouhadoun A, Bassiouni W, Goepp M, Mani S, Manikpurage HD, Senbel A, Longrois D, Heinemann A, Yao C, Clapp LH. International Union of Basic and Clinical Pharmacology. CIX. Differences and Similarities between Human and Rodent Prostaglandin E 2 Receptors (EP1-4) and Prostacyclin Receptor (IP): Specific Roles in Pathophysiologic Conditions. Pharmacol Rev 2020; 72:910-968. [PMID: 32962984 PMCID: PMC7509579 DOI: 10.1124/pr.120.019331] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Prostaglandins are derived from arachidonic acid metabolism through cyclooxygenase activities. Among prostaglandins (PGs), prostacyclin (PGI2) and PGE2 are strongly involved in the regulation of homeostasis and main physiologic functions. In addition, the synthesis of these two prostaglandins is significantly increased during inflammation. PGI2 and PGE2 exert their biologic actions by binding to their respective receptors, namely prostacyclin receptor (IP) and prostaglandin E2 receptor (EP) 1-4, which belong to the family of G-protein-coupled receptors. IP and EP1-4 receptors are widely distributed in the body and thus play various physiologic and pathophysiologic roles. In this review, we discuss the recent advances in studies using pharmacological approaches, genetically modified animals, and genome-wide association studies regarding the roles of IP and EP1-4 receptors in the immune, cardiovascular, nervous, gastrointestinal, respiratory, genitourinary, and musculoskeletal systems. In particular, we highlight similarities and differences between human and rodents in terms of the specific roles of IP and EP1-4 receptors and their downstream signaling pathways, functions, and activities for each biologic system. We also highlight the potential novel therapeutic benefit of targeting IP and EP1-4 receptors in several diseases based on the scientific advances, animal models, and human studies. SIGNIFICANCE STATEMENT: In this review, we present an update of the pathophysiologic role of the prostacyclin receptor, prostaglandin E2 receptor (EP) 1, EP2, EP3, and EP4 receptors when activated by the two main prostaglandins, namely prostacyclin and prostaglandin E2, produced during inflammatory conditions in human and rodents. In addition, this comparison of the published results in each tissue and/or pathology should facilitate the choice of the most appropriate model for the future studies.
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Affiliation(s)
- Xavier Norel
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Yukihiko Sugimoto
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Gulsev Ozen
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Heba Abdelazeem
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Yasmine Amgoud
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Amel Bouhadoun
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Wesam Bassiouni
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Marie Goepp
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Salma Mani
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Hasanga D Manikpurage
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Amira Senbel
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Dan Longrois
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Akos Heinemann
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Chengcan Yao
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
| | - Lucie H Clapp
- Université de Paris, Institut National de la Sante et de la Recherche Medicale (INSERM), UMR-S 1148, CHU X. Bichat, Paris, France (X.N., G.O., H.A., Y.A., A.B., S.M., H.D.M., A.S., D.L.); Université Sorbonne Paris Nord, Villetaneuse, France (X.N., H.A., Y.A., A.B., S.M., D.L.); Department of Pharmaceutical Biochemistry, Graduate School of Pharmaceutical Sciences, Kumamoto University, Chuo-ku, Kumamoto, Japan (Y.S.); Istanbul University, Faculty of Pharmacy, Department of Pharmacology, Istanbul, Turkey (G.O.); Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt (A.S., H.A., W.B.); Centre for Inflammation Research, Queen's Medical Research Institute, The University of Edinburgh, Edinburgh, United Kingdom (C.Y., M.G.); Institut Supérieur de Biotechnologie de Monastir (ISBM), Université de Monastir, Monastir, Tunisia (S.M.); CHU X. Bichat, AP-HP, Paris, France (D.L.); Otto Loewi Research Center for Vascular Biology, Immunology and Inflammation, Division of Pharmacology, Medical University of Graz, Graz, Austria (A.H.); and Centre for Cardiovascular Physiology & Pharmacology, University College London, London, United Kingdom (L.H.C.)
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8
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Structural Complexity and Plasticity of Signaling Regulation at the Melanocortin-4 Receptor. Int J Mol Sci 2020; 21:ijms21165728. [PMID: 32785054 PMCID: PMC7460885 DOI: 10.3390/ijms21165728] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 02/06/2023] Open
Abstract
The melanocortin-4 receptor (MC4R) is a class A G protein-coupled receptor (GPCR), essential for regulation of appetite and metabolism. Pathogenic inactivating MC4R mutations are the most frequent cause of monogenic obesity, a growing medical and socioeconomic problem worldwide. The MC4R mediates either ligand-independent or ligand-dependent signaling. Agonists such as α-melanocyte-stimulating hormone (α-MSH) induce anorexigenic effects, in contrast to the endogenous inverse agonist agouti-related peptide (AgRP), which causes orexigenic effects by suppressing high basal signaling activity. Agonist action triggers the binding of different subtypes of G proteins and arrestins, leading to concomitant induction of diverse intracellular signaling cascades. An increasing number of experimental studies have unraveled molecular properties and mechanisms of MC4R signal transduction related to physiological and pathophysiological aspects. In addition, the MC4R crystal structure was recently determined at 2.75 Å resolution in an inactive state bound with a peptide antagonist. Underpinned by structural homology models of MC4R complexes simulating a presumably active-state conformation compared to the structure of the inactive state, we here briefly summarize the current understanding and key players involved in the MC4R switching process between different activity states. Finally, these perspectives highlight the complexity and plasticity in MC4R signaling regulation and identify gaps in our current knowledge.
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9
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Vilela DAD, Silva BAO, Brito MC, Menezes PMN, Bomfim HF, Duarte-Filho LAMDS, Silva TRDS, Ribeiro LADA, Lucchese AM, Silva FS. Lippia alnifolia essential oil induces relaxation on Guinea-pig trachea by multiple pathways. JOURNAL OF ETHNOPHARMACOLOGY 2020; 246:112162. [PMID: 31419501 DOI: 10.1016/j.jep.2019.112162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 07/22/2019] [Accepted: 08/11/2019] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Lippia alnifolia Mart. & Schauer, known as "alecrim-do-mato", "alecrim-de-vaqueiro" and "pedrécio", is used in folk medicine as antiseptic and to treat diseases that affect respiratory system, like bronchitis and asthma. AIM OF THE STUDY The aim of this work was to investigate the spasmolytic activity and relaxant mechanism of the Lippia alnifolia essential oil (EOLA) on isolated guinea-pig trachea and to correlate with its use in folk medicine. MATERIALS AND METHODS Leaves from L. alnifolia were collected in Pico das Almas, Chapada Diamantina, situated in the city of Rio de Contas, Bahia, Brazil. EOLA was extracted by hydrodistillation, analyzed by GC/FID and GC/MS and the volatile constituents were identified. Spasmolytic activity was assayed in isolated guinea-pig trachea pre-contracted with carbachol 1 μM or histamine 10 μM. Relaxant mechanism of EOLA was determined comparing concentration-response curves in the presence or absence of different blockers. RESULTS Chemical analysis revealed the presence of carvone (60 ± 0.8%) as major constituent. EOLA (1-243 μg/mL) relaxed isolated guinea-pig trachea pre-contracted with carbachol 1 μM [EC50 = 53.36 (44.75-63.51) μg/mL] or histamine 10 μM [EC50 = 5.42 (4.42-6.65) μg/mL]. The pre-incubation of 4-aminopyridine in histamine-induced contractions did not alter significantly the relaxant effect of EOLA. However, the presence of cesium chloride, glibenclamide, tetraethylammonium, propranolol, indomethacin, dexamethasone, hexamethonium, atropine, L-NAME, methylene blue or ODQ reduced EOLA relaxant effect. EOLA 18 μg/mL pre-incubation in calcium-free medium reduced histamine-evoked contractions, but did not alter histamine contractions in the presence of nifedipine. CONCLUSIONS Lippia alnifolia essential oil has spasmolytic activity on isolated guinea-pig trachea and its mechanism of action possibly involves the activation of multiple signal transduction pathways, which culminate in potassium channels activation and cytosolic calcium reduction.
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Affiliation(s)
| | | | - Mariana Coelho Brito
- Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | | | - Horácio Freitas Bomfim
- Laboratório de Química de Produtos Naturais e Bioativos, Departamento de Ciências Exatas, Universidade Estadual de Feira de Santana (UEFS), Brazil.
| | | | | | - Luciano Augusto de Araújo Ribeiro
- Pós-graduação em Biociências, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil; Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
| | - Angélica Maria Lucchese
- Laboratório de Química de Produtos Naturais e Bioativos, Departamento de Ciências Exatas, Universidade Estadual de Feira de Santana (UEFS), Brazil.
| | - Fabrício Souza Silva
- Pós-graduação em Biociências, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil; Laboratório de Farmacologia Experimental, Colegiado de Farmácia, Universidade Federal do Vale do São Francisco (UNIVASF), Brazil.
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10
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Cardet JC, Jiang X, Lu Q, Gerard N, McIntire K, Boushey HA, Castro M, Chinchilli VM, Codispoti CD, Dyer AM, Holguin F, Kraft M, Lazarus S, Lemanske RF, Lugogo N, Mauger D, Moore WC, Moy J, Ortega VE, Peters SP, Smith LJ, Solway J, Sorkness CA, Sumino K, Wechsler ME, Wenzel S, Israel E. Loss of bronchoprotection with ICS plus LABA treatment, β-receptor dynamics, and the effect of alendronate. J Allergy Clin Immunol 2019; 144:416-425.e7. [PMID: 30872116 PMCID: PMC6950766 DOI: 10.1016/j.jaci.2019.01.049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 12/14/2018] [Accepted: 01/23/2019] [Indexed: 11/15/2022]
Abstract
BACKGROUND Loss of bronchoprotection (LOBP) with a regularly used long-acting β2-adrenergic receptor agonist (LABA) is well documented. LOBP has been attributed to β2-adrenergic receptor (B2AR) downregulation, a process requiring farnesylation, which is inhibited by alendronate. OBJECTIVE We sought to determine whether alendronate can reduce LABA-associated LOBP in inhaled corticosteroid (ICS)-treated patients. METHODS We conducted a randomized, double-blind, placebo-controlled, parallel-design, proof-of-concept trial. Seventy-eight participants with persistent asthma receiving 250 μg of fluticasone twice daily for 2 weeks were randomized to receive alendronate or placebo while initiating salmeterol for 8 weeks. Salmeterol-protected methacholine challenges (SPMChs) and PBMC B2AR numbers (radioligand binding assay) and signaling (cyclic AMP ELISA) were assessed before randomization and after 8 weeks of ICS plus LABA treatment. LOBP was defined as a more than 1 doubling dose reduction in SPMCh PC20 value. RESULTS The mean doubling dose reduction in SPMCh PC20 value was 0.50 and 0.27 with alendronate and placebo, respectively (P = .62). Thirty-eight percent of participants receiving alendronate and 33% receiving placebo had LOBP (P = .81). The after/before ICS plus LABA treatment ratio of B2AR number was 1.0 for alendronate (P = .86) and 0.8 for placebo (P = .15; P = .31 for difference between treatments). The B2AR signaling ratio was 0.89 for alendronate (P = .43) and 1.02 for placebo (P = .84; P = .44 for difference). Changes in lung function and B2AR number and signaling were similar between those who did and did not experience LOBP. CONCLUSION This study did not find evidence that alendronate reduces LABA-associated LOBP, which relates to the occurrence of LOBP in only one third of participants. LOBP appears to be less common than presumed in concomitant ICS plus LABA-treated asthmatic patients. B2AR downregulation measured in PBMCs does not appear to reflect LOBP.
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Affiliation(s)
| | - Xiaofeng Jiang
- Departments of Environmental Health, Genetics & Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, Mass
| | - Quan Lu
- Departments of Environmental Health, Genetics & Complex Diseases, Harvard T.H. Chan School of Public Health, Boston, Mass
| | - Norma Gerard
- Department of Pediatrics, Boston Children's Hospital, Boston, Mass
| | - Kristen McIntire
- Department of Medicine, Brigham and Women's Hospital, Boston, Mass
| | - Homer A Boushey
- Department of Medicine, University of California San Francisco, San Francisco, Calif
| | - Mario Castro
- Department of Medicine, Washington University, St Louis, Mo
| | - Vernon M Chinchilli
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, Pa
| | - Christopher D Codispoti
- Department of Medicine, Rush University Medical Center and Department of Pediatrics, Stroger Hospital of Cook County, Chicago, Ill
| | - Anne-Marie Dyer
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, Pa
| | | | - Monica Kraft
- Department of Medicine, University of Arizona, Tucson, Ariz
| | - Stephen Lazarus
- Department of Medicine, University of California San Francisco, San Francisco, Calif
| | - Robert F Lemanske
- Departments of Medicine and Pharmacy Practice, University of Wisconsin, Madison, Wis
| | - Njira Lugogo
- Department of Medicine, Duke University, Durham, NC
| | - Dave Mauger
- Department of Public Health Sciences, Penn State College of Medicine, Hershey, Pa
| | - Wendy C Moore
- Department of Internal Medicine, Wake Forest University, Winston-Salem, NC
| | - James Moy
- Department of Medicine, Rush University Medical Center and Department of Pediatrics, Stroger Hospital of Cook County, Chicago, Ill
| | - Victor E Ortega
- Department of Internal Medicine, Wake Forest University, Winston-Salem, NC
| | - Stephen P Peters
- Department of Internal Medicine, Wake Forest University, Winston-Salem, NC
| | - Lewis J Smith
- Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Ill
| | - Julian Solway
- Department of Medicine, University of Chicago, Chicago, Ill
| | - Christine A Sorkness
- Departments of Medicine and Pharmacy Practice, University of Wisconsin, Madison, Wis
| | - Kaharu Sumino
- Department of Medicine, Washington University, St Louis, Mo
| | | | - Sally Wenzel
- Department of Medicine, Pittsburgh University, Pittsburgh, Pa
| | - Elliot Israel
- Department of Medicine, Brigham and Women's Hospital, Boston, Mass.
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11
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Sleno R, Hébert TE. Shaky ground - The nature of metastable GPCR signalling complexes. Neuropharmacology 2019; 152:4-14. [PMID: 30659839 DOI: 10.1016/j.neuropharm.2019.01.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 12/20/2018] [Accepted: 01/16/2019] [Indexed: 01/19/2023]
Abstract
How G protein-coupled receptors (GPCR) interact with one another remains an area of active investigation. Obligate dimers of class C GPCRs such as metabotropic GABA and glutamate receptors are well accepted, although whether this is a general feature of other GPCRs is still strongly debated. In this review, we focus on the idea that GPCR dimers and oligomers are better imagined as parts of larger metastable signalling complexes. We discuss the nature of functional oligomeric entities, their stabilities and kinetic features and how structural and functional asymmetries of such metastable entities might have implications for drug discovery. This article is part of the Special Issue entitled 'Receptor heteromers and their allosteric receptor-receptor interactions'.
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Affiliation(s)
- Rory Sleno
- Marketed Pharmaceuticals and Medical Devices Bureau, Marketed Health Products Directorate, Health Products and Food Branch, Health Canada, Canada
| | - Terence E Hébert
- Department of Pharmacology and Therapeutics, McGill University, Canada.
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12
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Heyder N, Kleinau G, Szczepek M, Kwiatkowski D, Speck D, Soletto L, Cerdá-Reverter JM, Krude H, Kühnen P, Biebermann H, Scheerer P. Signal Transduction and Pathogenic Modifications at the Melanocortin-4 Receptor: A Structural Perspective. Front Endocrinol (Lausanne) 2019; 10:515. [PMID: 31417496 PMCID: PMC6685040 DOI: 10.3389/fendo.2019.00515] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/15/2019] [Indexed: 12/19/2022] Open
Abstract
The melanocortin-4 receptor (MC4R) can be endogenously activated by binding of melanocyte-stimulating hormones (MSH), which mediates anorexigenic effects. In contrast, the agouti-related peptide (AgRP) acts as an endogenous inverse agonist and suppresses ligand-independent basal signaling activity (orexigenic effects). Binding of ligands to MC4R leads to the activation of different G-protein subtypes or arrestin and concomitant signaling pathways. This receptor is a key protein in the hypothalamic regulation of food intake and energy expenditure and naturally-occurring inactivating MC4R variants are the most frequent cause of monogenic obesity. In general, obesity is a growing problem on a global scale and is of social, medical, and economic relevance. A significant goal is to develop optimized pharmacological tools targeting MC4R without adverse effects. To date, this has not been achieved because of inter alia non-selective ligands across the five functionally different MCR subtypes (MC1-5R). This motivates further investigation of (i) the three-dimensional MC4R structure, (ii) binding mechanisms of various ligands, and (iii) the molecular transfer process of signal transduction, with the aim of understanding how structural features are linked with functional-physiological aspects. Unfortunately, experimentally elucidated structural information is not yet available for the MC receptors, a group of class A G-protein coupled receptors (GPCRs). We, therefore, generated MC4R homology models and complexes with interacting partners to describe approximate structural properties associated with signaling mechanisms. In addition, molecular insights from pathogenic mutations were incorporated to discriminate more precisely their individual malfunction of the signal transfer mechanism.
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Affiliation(s)
- Nicolas Heyder
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Gunnar Kleinau
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
- *Correspondence: Gunnar Kleinau
| | - Michal Szczepek
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dennis Kwiatkowski
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - David Speck
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Lucia Soletto
- Departamento de Fisiología de Peces y Biotecnología, Consejo Superior de Investigaciones Científicas, Instituto de Acuicultura Torre de la Sal, Ribera de Cabanes, Spain
| | - José Miguel Cerdá-Reverter
- Departamento de Fisiología de Peces y Biotecnología, Consejo Superior de Investigaciones Científicas, Instituto de Acuicultura Torre de la Sal, Ribera de Cabanes, Spain
| | - Heiko Krude
- Institute of Experimental Pediatric Endocrinology, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Peter Kühnen
- Institute of Experimental Pediatric Endocrinology, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Patrick Scheerer
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
- Patrick Scheerer
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13
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Sleno R, Hébert TE. The Dynamics of GPCR Oligomerization and Their Functional Consequences. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2018; 338:141-171. [PMID: 29699691 DOI: 10.1016/bs.ircmb.2018.02.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The functional importance of G protein-coupled receptor (GPCR) oligomerization remains controversial. Although obligate dimers of class C GPCRs are well accepted, the generalizability of this phenomenon is still strongly debated with respect to other classes of GPCRs. In this review, we focus on understanding the organization and dynamics between receptor equivalents and their signaling partners in oligomeric receptor complexes, with a view toward integrating disparate viewpoints into a unified understanding. We discuss the nature of functional oligomeric entities, and how asymmetries in receptor structure and function created by oligomers might have implications for receptor function as allosteric machines and for future drug discovery.
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14
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Farran B. An update on the physiological and therapeutic relevance of GPCR oligomers. Pharmacol Res 2017; 117:303-327. [PMID: 28087443 DOI: 10.1016/j.phrs.2017.01.008] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 01/06/2017] [Accepted: 01/09/2017] [Indexed: 01/17/2023]
Abstract
The traditional view on GPCRs held that they function as single monomeric units composed of identical subunits. This notion was overturned by the discovery that GPCRs can form homo- and hetero-oligomers, some of which are obligatory, and can further assemble into receptor mosaics consisting of three or more protomers. Oligomerisation exerts significant impacts on receptor function and physiology, offering a platform for the diversification of receptor signalling, pharmacology, regulation, crosstalk, internalization and trafficking. Given their involvement in the modulation of crucial physiological processes, heteromers could constitute important therapeutic targets for a wide range of diseases, including schizophrenia, Parkinson's disease, substance abuse or obesity. This review aims at depicting the current developments in GPCR oligomerisation research, documenting various class A, B and C GPCR heteromers detected in vitro and in vivo using biochemical and biophysical approaches, as well as recently identified higher-order oligomeric complexes. It explores the current understanding of dimerization dynamics and the possible interaction interfaces that drive oligomerisation. Most importantly, it provides an inventory of the wide range of physiological processes and pathophysiological conditions to which GPCR oligomers contribute, surveying some of the oligomers that constitute potential drug targets. Finally, it delineates the efforts to develop novel classes of ligands that specifically target and tether to receptor oligomers instead of a single monomeric entity, thus ameliorating their ability to modulate GPCR function.
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Affiliation(s)
- Batoul Farran
- Department of Structural and Molecular Biology, University College London, Gower Street, London, WC1E 6BT, United Kingdom.
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15
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Rumzhum NN, Ammit AJ. Cyclooxygenase 2: its regulation, role and impact in airway inflammation. Clin Exp Allergy 2016; 46:397-410. [PMID: 26685098 DOI: 10.1111/cea.12697] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Cyclooxygenase 2 (COX-2: official gene symbol - PTGS2) has long been regarded as playing a pivotal role in the pathogenesis of airway inflammation in respiratory diseases including asthma. COX-2 can be rapidly and robustly expressed in response to a diverse range of pro-inflammatory cytokines and mediators. Thus, increased levels of COX-2 protein and prostanoid metabolites serve as key contributors to pathobiology in respiratory diseases typified by dysregulated inflammation. But COX-2 products may not be all bad: prostanoids can exert anti-inflammatory/bronchoprotective functions in airways in addition to their pro-inflammatory actions. Herein, we outline COX-2 regulation and review the diverse stimuli known to induce COX-2 in the context of airway inflammation. We discuss some of the positive and negative effects that COX-2/prostanoids can exert in in vitro and in vivo models of airway inflammation, and suggest that inhibiting COX-2 expression to repress airway inflammation may be too blunt an approach; because although it might reduce the unwanted effects of COX-2 activation, it may also negate the positive effects. Evidence suggests that prostanoids produced via COX-2 upregulation show diverse actions (and herein we focus on prostaglandin E2 as a key example); these can be either beneficial or deleterious and their impact on respiratory disease can be dictated by local concentration and specific interaction with individual receptors. We propose that understanding the regulation of COX-2 expression and associated receptor-mediated functional outcomes may reveal number of critical steps amenable to pharmacological intervention. These may prove invaluable in our quest towards future development of novel anti-inflammatory pharmacotherapeutic strategies for the treatment of airway diseases.
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Affiliation(s)
- N N Rumzhum
- Faculty of Pharmacy, University of Sydney, Sydney, NSW, Australia
| | - A J Ammit
- Faculty of Pharmacy, University of Sydney, Sydney, NSW, Australia
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16
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Kim D, Pauer SH, Yong HM, An SS, Liggett SB. β2-Adrenergic Receptors Chaperone Trapped Bitter Taste Receptor 14 to the Cell Surface as a Heterodimer and Exert Unidirectional Desensitization of Taste Receptor Function. J Biol Chem 2016; 291:17616-28. [PMID: 27342779 PMCID: PMC5016158 DOI: 10.1074/jbc.m116.722736] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Indexed: 12/28/2022] Open
Abstract
Bitter taste receptors (TAS2Rs) are G-protein-coupled receptors now recognized to be expressed on extraoral cells, including airway smooth muscle (ASM) where they evoke relaxation. TAS2Rs are difficult to express in heterologous systems, with most receptors being trapped intracellularly. We find, however, that co-expression of β2-adrenergic receptors (β2AR) in HEK-293T routes TAS2R14 to the cell surface by forming receptor heterodimers. Cell surface TAS2R14 expression was increased by ∼5-fold when β2AR was co-expressed. Heterodimer formation was shown by co-immunoprecipitation with tagged receptors, biomolecular fluorescence complementation, and merged confocal images. The dynamic nature of this interaction was shown by: a gene-dose relationship between transfected β2AR and TAS2R14 expression, enhanced (up to 3-fold) TAS2R14 agonist stimulation of [Ca2+]i with β2AR co-transfection, ∼53% decrease in [Ca2+]i signaling with shRNA knockdown of β2AR in H292 cells, and ∼60% loss of [Ca2+]i responsiveness in βAR knock-out mouse ASM. Once expressed on the surface, we detected unidirectional, conformation-dependent, interaction within the heterodimer, with β2AR activation rapidly uncoupling TAS2R14 function (∼65% desensitization). Cross-talk was independent of β2AR internalization and cAMP/PKA, and not accompanied by TAS2R14 internalization. With prolonged β-agonist exposure, TAS2R14 internalized, consistent with slow recycling of naked TAS2R14 in the absence of the heterodimeric milieu. In studies of ASM mechanics, rapid cross-talk was confirmed at the physiologic level, where relaxation from TAS2R14 agonist was decreased by ∼50% with β-agonist co-treatment. Thus the β2AR acts as a double-edged sword: increasing TAS2R14 cell surface expression, but when activated by β-agonist, partially offsetting the expression phenotype by direct receptor:receptor desensitization of TAS2R14 function.
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Affiliation(s)
- Donghwa Kim
- From the Departments of Medicine and the Center for Personalized Medicine and Genomics, University of South Florida Morsani College of Medicine, Tampa, Florida 33612 and
| | - Susan H Pauer
- the Center for Personalized Medicine and Genomics, University of South Florida Morsani College of Medicine, Tampa, Florida 33612 and
| | - Hwan M Yong
- the Department of Environmental Health Sciences, The Johns Hopkins University, Bloomberg School of Public Health, Baltimore, Maryland 21205
| | - Steven S An
- the Department of Environmental Health Sciences, The Johns Hopkins University, Bloomberg School of Public Health, Baltimore, Maryland 21205
| | - Stephen B Liggett
- From the Departments of Medicine and the Center for Personalized Medicine and Genomics, University of South Florida Morsani College of Medicine, Tampa, Florida 33612 and Molecular Pharmacology and Physiology, and
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17
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Kobayashi Y, Hamamoto A, Takahashi A, Saito Y. Dimerization of melanocortin receptor 1 (MC1R) and MC5R creates a ligand-dependent signal modulation: Potential participation in physiological color change in the flounder. Gen Comp Endocrinol 2016; 230-231:103-9. [PMID: 27080548 DOI: 10.1016/j.ygcen.2016.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Revised: 03/31/2016] [Accepted: 04/09/2016] [Indexed: 01/21/2023]
Abstract
Vertebrates produce α-melanocyte-stimulating hormone (α-MSH), which contains an N-terminal acetyl group, and desacetyl-α-MSH, which does not contain an N-terminal acetyl group. In teleosts and amphibians, α-MSH-related peptides stimulate pigment dispersion via melanocortin receptors 1-5 (MC1R-MC5R), which are members of the G-protein-coupled receptor (GPCR) family. We previously reported an interesting phenomenon associated with physiological color changes in the skin of a flatfish, barfin flounder (bf). Specifically, pigments in xanthophores expressing only the bfMC5R gene were dispersed by both α-MSH and desacetyl-α-MSH, whereas those in melanophores expressing both the bfMC1R and bfMC5R genes were dispersed by desacetyl-α-MSH, but not by α-MSH. In this study, we examined whether heterodimers of bfMC1R and bfMC5R can act as significant inhibitory receptors for the N-terminal acetylation of α-MSH in mammalian Chinese hamster ovary cells. Immunofluorescence analyses showed that bfMC1R and bfMC5R were localized together at the plasma membrane when expressed in the same cells. Indeed, after coexpression of Flag-bfMC1R and HA-bfMC5R, immunoprecipitation with anti-Flag antibodies resulted in the presence of anti-HA immunoreactivity in the precipitate, and vice versa. Importantly, cyclic AMP assays showed that cotransfection of bfMC1R with bfMC5R inhibited the cyclic AMP accumulation induced by α-MSH to a greater extent than that observed after transfection of bfMC1R alone. Of note, this inhibitory response was not caused by desacetyl-α-MSH. Thus, we show a ligand-dependent signaling through functional heterodimerization of MC1R and MC5R in mammalian cells. The ligand-selective receptor complex also provide the first mechanistic implication that may play a role in the control of color change in teleosts.
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Affiliation(s)
- Yuki Kobayashi
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | - Akie Hamamoto
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan
| | | | - Yumiko Saito
- Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, Japan.
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18
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Łukasiewicz S, Błasiak E, Szafran-Pilch K, Dziedzicka-Wasylewska M. Dopamine D2 and serotonin 5-HT1A receptor interaction in the context of the effects of antipsychotics - in vitro studies. J Neurochem 2016; 137:549-60. [PMID: 26876117 DOI: 10.1111/jnc.13582] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 02/04/2016] [Accepted: 02/05/2016] [Indexed: 12/11/2022]
Abstract
The serotonin 5-HT1A receptor (5-HT1 A R) and dopamine D2 receptor (D2 R) have been implicated as important sites of action in antipsychotics. Several lines of evidence indicate the key role of G protein-coupled receptors (GPCRs) heteromers in pathophysiology of schizophrenia and highlight these complexes as novel drug targets. Because heterodimers can form only on those cells co-expressing constituent receptors, they present a target of high pharmacological specificity in the context of biochemical effects induced by antipsychotic drugs. In studies conducted in the HEK 293 cell line, we demonstrated that 5-HT1 A R and D2 R are able to form constitutive heterodimers, and antipsychotic drugs (clozapine, olanzapine, aripiprazole, and lurasidone) enhanced this process, with clozapine being most effective. Various functional tests (cAMP and IP1 as well as ERK activation) indicated that the drugs had different effects on signal transduction by the heteromer. Interestingly, co-incubation of heterodimer-expressing HEK 293 cells with clozapine and the 5-HT1 A R agonist 8-OH DPAT potentiated post-synaptic effects, especially with respect to ERK activation. Our results indicate that the D2 -5-HT1A complex possesses biochemical, pharmacological, and functional properties distinct from those of mono- and homomers. This result has implications for the development of improved pharmacotherapy for schizophrenia or other disorders (activating the heteromer might be cognitive enhancing, since it is expressed in frontal cortex) through the specific targeting of heterodimers. We reported the constitutive formation of D2 -5-HT1A heteromers, which possess biochemical, pharmacological, and functional properties distinct from those of mono- and homomers, as revealed by antipsychotics action. We also showed that these two receptors are co-expressed in mouse cortical neurons; therefore their potential to heterodimerize may comprise an essential target for the development of novel strategies for schizophrenia treatment.
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Affiliation(s)
- Sylwia Łukasiewicz
- Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | - Ewa Błasiak
- Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
| | | | - Marta Dziedzicka-Wasylewska
- Department of Physical Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Krakow, Poland
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19
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Jones VC, Birrell MA, Maher SA, Griffiths M, Grace M, O'Donnell VB, Clark SR, Belvisi MG. Role of EP2 and EP4 receptors in airway microvascular leak induced by prostaglandin E2. Br J Pharmacol 2016; 173:992-1004. [PMID: 26639895 PMCID: PMC4831025 DOI: 10.1111/bph.13400] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 10/21/2015] [Accepted: 11/30/2015] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND AND PURPOSE Airway microvascular leak (MVL) involves the extravasation of proteins from post-capillary venules into surrounding tissue. MVL is a cardinal sign of inflammation and an important feature of airway inflammatory diseases such as asthma. PGE2, a product of COX-mediated metabolism of arachidonic acid, binds to four receptors, termed EP1–4. PGE2 has a wide variety of effects within the airway, including modulation of inflammation, sensory nerve activation and airway tone. However, the effect of PGE2 on airway MVL and the receptor/s that mediate this have not been described. EXPERIMENTAL APPROACH Evans Blue dye was used as a marker of airway MVL, and selective EP receptor agonists and antagonists were used alongside EP receptor-deficient mice to define the receptor subtype involved. KEY RESULTS PGE2 induced significant airway MVL in mice and guinea pigs. A significant reduction in PGE2-induced MVL was demonstrated in Ptger2−/− and Ptger4−/− mice and in wild-type mice pretreated simultaneously with EP2 (PF-04418948) and EP4 (ER-819762) receptor antagonists. In a model of allergic asthma, an increase in airway levels of PGE2 was associated with a rise in MVL; this change was absent in Ptger2−/− and Ptger4−/− mice. CONCLUSIONS AND IMPLICATIONS PGE2 is a key mediator produced by the lung and has widespread effects according to the EP receptor activated. Airway MVL represents a response to injury and under ‘disease’ conditions is a prominent feature of airway inflammation. The data presented highlight a key role for EP2 and EP4 receptors in MVL induced by PGE2.
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MESH Headings
- Allergens
- Animals
- Asthma/metabolism
- Azetidines/pharmacology
- Benzazepines/pharmacology
- Bronchi/metabolism
- Capillary Permeability
- Dinoprostone/analogs & derivatives
- Dinoprostone/metabolism
- Dinoprostone/pharmacology
- Guinea Pigs
- Imidazoles/pharmacology
- Male
- Methyl Ethers/pharmacology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Ovalbumin
- Receptors, Prostaglandin E, EP2 Subtype/agonists
- Receptors, Prostaglandin E, EP2 Subtype/antagonists & inhibitors
- Receptors, Prostaglandin E, EP2 Subtype/genetics
- Receptors, Prostaglandin E, EP2 Subtype/metabolism
- Receptors, Prostaglandin E, EP4 Subtype/agonists
- Receptors, Prostaglandin E, EP4 Subtype/antagonists & inhibitors
- Receptors, Prostaglandin E, EP4 Subtype/genetics
- Receptors, Prostaglandin E, EP4 Subtype/metabolism
- Trachea/metabolism
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20
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Abstract
G protein-coupled receptors (GPCRs) compose one of the largest families of membrane proteins involved in intracellular signaling. They are involved in numerous physiological and pathological processes and are prime candidates for drug development. Over the past decade, an increasing number of studies have reported heteromerization between GPCRs. Many investigations in heterologous systems have provided important indications of potential novel pharmacology; however, the physiological relevance of these findings has yet to be established with endogenous receptors in native tissues. In this review, we focus on family A GPCRs and describe the techniques and criteria to assess their heteromerization. We conclude that advances in approaches to study receptor complex functionality in heterologous systems, coupled with techniques that enable specific examination of native receptor heteromers in vivo, are likely to establish GPCR heteromers as novel therapeutic targets.
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Affiliation(s)
- Ivone Gomes
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029;
| | - Mohammed Akli Ayoub
- Biologie et Bioinformatique des Systèmes de Signalisation (BIOS) Group, INRA, UMR85, Unité Physiologie de la Reproduction et des Comportements; CNRS, UMR7247, F-37380 Nouzilly, France
- LE STUDIUM Loire Valley Institute for Advanced Studies, F-45000 Orleans, France
| | - Wakako Fujita
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029;
- Current address: Department of Frontier Life Sciences, Nagasaki University, Nagasaki City, Nagasaki Prefecture 852-8588, Japan
| | - Werner C Jaeger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, Nedlands, Western Australia 6009, Australia
- Centre for Medical Research, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Kevin D G Pfleger
- Molecular Endocrinology and Pharmacology, Harry Perkins Institute of Medical Research, Nedlands, Western Australia 6009, Australia
- Centre for Medical Research, The University of Western Australia, Crawley, Western Australia 6009, Australia
- Dimerix Bioscience Limited, Nedlands, Western Australia 6009, Australia
| | - Lakshmi A Devi
- Department of Pharmacology and Systems Therapeutics, Icahn School of Medicine at Mount Sinai, New York, NY 10029;
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21
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Dinter J, Mühlhaus J, Jacobi SF, Wienchol CL, Cöster M, Meister J, Hoefig CS, Müller A, Köhrle J, Grüters A, Krude H, Mittag J, Schöneberg T, Kleinau G, Biebermann H. 3-iodothyronamine differentially modulates α-2A-adrenergic receptor-mediated signaling. J Mol Endocrinol 2015; 54:205-16. [PMID: 25878061 DOI: 10.1530/jme-15-0003] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/10/2015] [Indexed: 11/08/2022]
Abstract
Most in vivo effects of 3-iodothyronamine (3-T1AM) have been thus far thought to be mediated by binding at the trace amine-associated receptor 1 (TAAR1). Inconsistently, the 3-T1AM-induced hypothermic effect still persists in Taar1 knockout mice, which suggests additional receptor targets. In support of this general assumption, it has previously been reported that 3-T1AM also binds to the α-2A-adrenergic receptor (ADRA2A), which modulates insulin secretion. However, the mechanism of this effect remains unclear. We tested two different scenarios that may explain the effect: the sole action of 3-T1AM at ADRA2A and a combined action of 3-T1AM at ADRA2A and TAAR1, which is also expressed in pancreatic islets. We first investigated a potential general signaling modification using the label-free EPIC technology and then specified changes in signaling by cAMP inhibition and MAPKs (ERK1/2) determination. We found that 3-T1AM induced Gi/o activation at ADRA2A and reduced the norepinephrine (NorEpi)-induced MAPK activation. Interestingly, in ADRA2A/TAAR1 hetero-oligomers, application of NorEpi resulted in uncoupling of the Gi/o signaling pathway, but it did not affect MAPK activation. However, 3-T1AM application in mice over a period of 6 days at a daily dose of 5 mg/kg had no significant effects on glucose homeostasis. In summary, we report an agonistic effect of 3-T1AM on the ADRA2A-mediated Gi/o pathway but an antagonistic effect on MAPK induced by NorEpi. Moreover, in ADRA2A/TAAR1 hetero-oligomers, the capacity of NorEpi to stimulate Gi/o signaling is reduced by co-stimulation with 3-T1AM. The present study therefore points to a complex spectrum of signaling modification mediated by 3-T1AM at different G protein-coupled receptors.
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Affiliation(s)
- Juliane Dinter
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Jessica Mühlhaus
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Simon Friedrich Jacobi
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Carolin Leonie Wienchol
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Maxi Cöster
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Jaroslawna Meister
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Carolin Stephanie Hoefig
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Anne Müller
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Josef Köhrle
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Annette Grüters
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Heiko Krude
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Jens Mittag
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Torsten Schöneberg
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Gunnar Kleinau
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
| | - Heike Biebermann
- Institut für Experimentelle Pädiatrische EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, GermanyDepartment of Cell and Molecular BiologyKarolinska Institutet, Stockholm, SwedenInstitut für BiochemieMolekulare Biochemie, Medizinische Fakultät, University of Leipzig, Leipzig, GermanyInstitut für Experimentelle EndokrinologieCharité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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22
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Sun GC, Ho WY, Chen BR, Cheng PW, Cheng WH, Hsu MC, Yeh TC, Hsiao M, Lu PJ, Tseng CJ. GPCR dimerization in brainstem nuclei contributes to the development of hypertension. Br J Pharmacol 2015; 172:2507-18. [PMID: 25573074 PMCID: PMC4409903 DOI: 10.1111/bph.13074] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 11/20/2014] [Accepted: 12/29/2014] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE μ-Opioid receptors, pro-opiomelanocortin and pro-enkephalin are highly expressed in the nucleus tractus solitarii (NTS) and μ receptor agonists given to the NTS dose-dependently increased BP. However, the molecular mechanisms of this process remain unclear. In vitro, μ receptors heterodimerize with α2A -adrenoceptors. We hypothesized that α2A -adrenoceptor agonists would lose their depressor effects when their receptors heterodimerize in the NTS with μ receptors. EXPERIMENTAL APPROACH We microinjected μ-opioid agonists and antagonists into the NTS of rats and measured changes in BP. Formation of μ receptor/α2A -adrenoceptor heterodimers was assessed with immunofluorescence and co-immunoprecipitation methods, along with proximity ligation assays. KEY RESULTS Immunofluorescence staining revealed colocalization of α2A -adrenoceptors and μ receptors in NTS neurons. Co-immunoprecipitation revealed interactions between α2A -adrenoceptors and μ receptors. In situ proximity ligation assays confirmed the presence of μ receptor/α2A -adrenoceptor heterodimers in the NTS. Higher levels of endogenous endomorphin-1 and μ receptor/α2A -adrenoceptor heterodimers were found in the NTS of hypertensive rats, than in normotensive rats. Microinjection of the μ receptor agonist [D-Ala(2) , MePhe(4) , Gly(5) -ol]-enkephalin (DAMGO), but not that of the α2A -adrenoceptor agonist guanfacine, into the NTS of normotensive rats increased μ receptor/α2A -adrenoceptor heterodimer formation and BP elevation. The NO-dependent BP-lowering effect of α2A -adrenoceptor agonists was blunted following increased formation of μ receptor/α2A -adrenoceptor heterodimers in the NTS of hypertensive rats and DAMGO-treated normotensive rats. CONCLUSIONS AND IMPLICATIONS Increases in endogenous μ receptor agonists in the NTS induced μ receptor/α2A -adrenoceptor heterodimer formation and reduced the NO-dependent depressor effect of α2A -adrenoceptor agonists. This process could contribute to the pathogenesis of hypertension.
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MESH Headings
- Adrenergic alpha-2 Receptor Agonists/administration & dosage
- Adrenergic alpha-2 Receptor Agonists/pharmacology
- Analgesics, Opioid/administration & dosage
- Analgesics, Opioid/pharmacology
- Animals
- Blood Pressure/drug effects
- Brain Stem/drug effects
- Brain Stem/metabolism
- Dimerization
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/administration & dosage
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-/pharmacology
- Hypertension/chemically induced
- Hypertension/metabolism
- Male
- Microinjections
- Narcotic Antagonists/administration & dosage
- Narcotic Antagonists/pharmacology
- Oligopeptides/metabolism
- Protein Multimerization
- Rats
- Rats, Inbred SHR
- Receptors, Adrenergic, alpha-2/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/metabolism
- Solitary Nucleus/drug effects
- Solitary Nucleus/metabolism
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Affiliation(s)
- Gwo-Ching Sun
- Institute of Clinical Medicine, National Cheng-Kung UniversityTainan, Taiwan
- Department of Anesthesiology, Kaohsiung Medical University Hospital, Kaohsiung Medical UniversityKaohsiung, Taiwan
- Department of Medical Education and Research, Kaohsiung Veterans General HospitalKaohsiung, Taiwan
| | - Wen-Yu Ho
- Division of General Internal Medicine, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical UniversityKaohsiung, Taiwan
- Department of Internal Medicine, Faculty of Medicine, College of Medicine, Kaohsiung Medical UniversityKaohsiung, Taiwan
- Department of Pharmacology, National Defense Medical CenterTaipei, Taiwan
| | - Bo-Rung Chen
- Department of Medical Education and Research, Kaohsiung Veterans General HospitalKaohsiung, Taiwan
| | - Pei-Wen Cheng
- Department of Medical Education and Research, Kaohsiung Veterans General HospitalKaohsiung, Taiwan
- Department of Pharmacology, National Defense Medical CenterTaipei, Taiwan
| | - Wen-Han Cheng
- Department of Medical Education and Research, Kaohsiung Veterans General HospitalKaohsiung, Taiwan
- Institute of Clinical Medicine, National Yang-Ming UniversityTaipei, Taiwan
| | - Mei-Chi Hsu
- Department of Nursing, I-Shou UniversityKaohsiung, Taiwan
| | - Tung-Chen Yeh
- Division of Cardiology, Department of Internal Medicine, Kaohsiung Veterans General HospitalKaohsiung, Taiwan
| | - Michael Hsiao
- Genomics Research Center, Academia SinicaTaipei, Taiwan
| | - Pei-Jung Lu
- Institute of Clinical Medicine, National Cheng-Kung UniversityTainan, Taiwan
| | - Ching-Jiunn Tseng
- Department of Medical Education and Research, Kaohsiung Veterans General HospitalKaohsiung, Taiwan
- Department of Pharmacology, National Defense Medical CenterTaipei, Taiwan
- Institute of Clinical Medicine, National Yang-Ming UniversityTaipei, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical UniversityTaichung, Taiwan
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23
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Tripathi A, Vana PG, Chavan TS, Brueggemann LI, Byron KL, Tarasova NI, Volkman BF, Gaponenko V, Majetschak M. Heteromerization of chemokine (C-X-C motif) receptor 4 with α1A/B-adrenergic receptors controls α1-adrenergic receptor function. Proc Natl Acad Sci U S A 2015; 112:E1659-68. [PMID: 25775528 PMCID: PMC4386352 DOI: 10.1073/pnas.1417564112] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Recent evidence suggests that chemokine (C-X-C motif) receptor 4 (CXCR4) contributes to the regulation of blood pressure through interactions with α1-adrenergic receptors (ARs) in vascular smooth muscle. The underlying molecular mechanisms, however, are unknown. Using proximity ligation assays to visualize single-molecule interactions, we detected that α1A/B-ARs associate with CXCR4 on the cell surface of rat and human vascular smooth muscle cells (VSMC). Furthermore, α1A/B-AR could be coimmunoprecipitated with CXCR4 in a HeLa expression system and in human VSMC. A peptide derived from the second transmembrane helix of CXCR4 induced chemical shift changes in the NMR spectrum of CXCR4 in membranes, disturbed the association between α1A/B-AR and CXCR4, and inhibited Ca(2+) mobilization, myosin light chain (MLC) 2 phosphorylation, and contraction of VSMC upon α1-AR activation. CXCR4 silencing reduced α1A/B-AR:CXCR4 heteromeric complexes in VSMC and abolished phenylephrine-induced Ca(2+) fluxes and MLC2 phosphorylation. Treatment of rats with CXCR4 agonists (CXCL12, ubiquitin) reduced the EC50 of the phenylephrine-induced blood pressure response three- to fourfold. These observations suggest that disruption of the quaternary structure of α1A/B-AR:CXCR4 heteromeric complexes by targeting transmembrane helix 2 of CXCR4 and depletion of the heteromeric receptor complexes by CXCR4 knockdown inhibit α1-AR-mediated function in VSMC and that activation of CXCR4 enhances the potency of α1-AR agonists. Our findings extend the current understanding of the molecular mechanisms regulating α1-AR and provide an example of the importance of G protein-coupled receptor (GPCR) heteromerization for GPCR function. Compounds targeting the α1A/B-AR:CXCR4 interaction could provide an alternative pharmacological approach to modulate blood pressure.
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Affiliation(s)
- Abhishek Tripathi
- Burn and Shock Trauma Research Institute, Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153
| | - P Geoff Vana
- Burn and Shock Trauma Research Institute, Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153
| | - Tanmay S Chavan
- Department of Medicinal Chemistry, University of Illinois, Chicago, IL 60607
| | - Lioubov I Brueggemann
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153
| | - Kenneth L Byron
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153
| | - Nadya I Tarasova
- Cancer and Inflammation Program, National Cancer Institute, Frederick, MD 21702-1201
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226; and
| | - Vadim Gaponenko
- Department of Biochemistry and Molecular Genetics, University of Illinois, Chicago, IL 60607
| | - Matthias Majetschak
- Burn and Shock Trauma Research Institute, Department of Surgery, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153; Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago Stritch School of Medicine, Maywood, IL 60153;
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24
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Demonstration of a direct interaction between β2-adrenergic receptor and insulin receptor by BRET and bioinformatics. PLoS One 2014; 9:e112664. [PMID: 25401701 PMCID: PMC4234468 DOI: 10.1371/journal.pone.0112664] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Accepted: 10/06/2014] [Indexed: 12/23/2022] Open
Abstract
Glucose metabolism is under the cooperative regulation of both insulin receptor (IR) and β2-adrenergic receptor (β2AR), which represent the receptor tyrosine kinases (RTKs) and seven transmembrane receptors (7TMRs), respectively. Studies demonstrating cross-talk between these two receptors and their endogenous coexpression have suggested their possible interactions. To evaluate the effect of IR and prospective heteromerization on β2AR properties, we showed that IR coexpression had no effect on the ligand binding properties of β2AR; however, IR reduced β2AR surface expression and accelerated its internalization. Additionally, both receptors displayed a similar distribution pattern with a high degree of colocalization. To test the possible direct interaction between β2AR and IR, we employed quantitative BRET2 saturation and competition assays. Saturation assay data suggested constitutive β2AR and IR homo- and heteromerization. Calculated acceptor/donor (AD50) values as a measure of the relative affinity for homo- and heteromer formation differed among the heteromers that could not be explained by a simple dimer model. In heterologous competition assays, a transient increase in the BRET2 signal with a subsequent hyperbolical decrease was observed, suggesting higher-order heteromer formation. To complement the BRET2 data, we employed the informational spectrum method (ISM), a virtual spectroscopy method to investigate protein-protein interactions. Computational peptide scanning of β2AR and IR identified intracellular domains encompassing residues at the end of the 7th TM domain and C-terminal tail of β2AR and a cytoplasmic part of the IR β chain as prospective interaction domains. ISM further suggested a high probability of heteromer formation and homodimers as basic units engaged in heteromerization. In summary, our data suggest direct interaction and higher-order β2AR:IR oligomer formation, likely comprising heteromers of homodimers.
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25
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Bach HH, Wong YM, Tripathi A, Nevins AM, Gamelli RL, Volkman BF, Byron KL, Majetschak M. Chemokine (C-X-C motif) receptor 4 and atypical chemokine receptor 3 regulate vascular α₁-adrenergic receptor function. Mol Med 2014; 20:435-47. [PMID: 25032954 DOI: 10.2119/molmed.2014.00101] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 07/14/2014] [Indexed: 12/23/2022] Open
Abstract
Chemokine (C-X-C motif) receptor (CXCR) 4 and atypical chemokine receptor (ACKR) 3 ligands have been reported to modulate cardiovascular function in various disease models. The underlying mechanisms, however, remain unknown. Thus, it was the aim of the present study to determine how pharmacological modulation of CXCR4 and ACKR3 regulate cardiovascular function. In vivo administration of TC14012, a CXCR4 antagonist and ACKR3 agonist, caused cardiovascular collapse in normal animals. During the cardiovascular stress response to hemorrhagic shock, ubiquitin, a CXCR4 agonist, stabilized blood pressure, whereas coactivation of CXCR4 and ACKR3 with CXC chemokine ligand 12 (CXCL12), or blockade of CXCR4 with AMD3100 showed opposite effects. While CXCR4 and ACKR3 ligands did not affect myocardial function, they selectively altered vascular reactivity upon α1-adrenergic receptor (AR) activation in pressure myography experiments. CXCR4 activation with ubiquitin enhanced α1-AR-mediated vasoconstriction, whereas ACKR3 activation with various natural and synthetic ligands antagonized α1-AR-mediated vasoconstriction. The opposing effects of CXCR4 and ACKR3 activation by CXCL12 could be dissected pharmacologically. CXCR4 and ACKR3 ligands did not affect vasoconstriction upon activation of voltage-operated Ca(2+) channels or endothelin receptors. Effects of CXCR4 and ACKR3 agonists on vascular α1-AR responsiveness were independent of the endothelium. These findings suggest that CXCR4 and ACKR3 modulate α1-AR reactivity in vascular smooth muscle and regulate hemodynamics in normal and pathological conditions. Our observations point toward CXCR4 and ACKR3 as new pharmacological targets to control vasoreactivity and blood pressure.
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Affiliation(s)
- Harold H Bach
- Department of Surgery, Loyola University Chicago, Maywood, Illinois, United States of America Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Yee M Wong
- Department of Surgery, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Abhishek Tripathi
- Department of Surgery, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Amanda M Nevins
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Richard L Gamelli
- Department of Surgery, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
| | - Kenneth L Byron
- Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Matthias Majetschak
- Department of Surgery, Loyola University Chicago, Maywood, Illinois, United States of America Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, Illinois, United States of America
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26
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Wnorowski A, Jozwiak K. Homo- and hetero-oligomerization of β2-adrenergic receptor in receptor trafficking, signaling pathways and receptor pharmacology. Cell Signal 2014; 26:2259-65. [PMID: 25049076 DOI: 10.1016/j.cellsig.2014.06.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 06/27/2014] [Indexed: 10/25/2022]
Abstract
The β2-adrenergic receptor (β2AR) is the prototypic member of G protein-coupled receptors (GPCRs) involved in the production of physiological responses to adrenaline and noradrenaline. Research done in the past few years vastly demonstrated that β2AR can form homo- and hetero-oligomers. Despite the fact that currently this phenomenon is widely accepted, the spread and relevance of β2AR oligomerization are still a matter of debate. This review considers the progress achieved in the field of β2AR oligomerization with focus on the implications of the receptor-receptor interactions to β2AR trafficking, pharmacology and downstream signal transduction pathways.
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Affiliation(s)
- Artur Wnorowski
- Laboratory of Medicinal Chemistry and Neuroengineering, Department of Chemistry, Medical University of Lublin, 20-093 Lublin, Poland.
| | - Krzysztof Jozwiak
- Laboratory of Medicinal Chemistry and Neuroengineering, Department of Chemistry, Medical University of Lublin, 20-093 Lublin, Poland.
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27
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Robinett KS, Koziol-White CJ, Akoluk A, An SS, Panettieri RA, Liggett SB. Bitter taste receptor function in asthmatic and nonasthmatic human airway smooth muscle cells. Am J Respir Cell Mol Biol 2014; 50:678-83. [PMID: 24219573 DOI: 10.1165/rcmb.2013-0439rc] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Bitter taste receptors (TAS2Rs) have recently been found to be expressed on human airway smooth muscle (HASM), and their activation results in marked relaxation. These agents have been proposed as a new class of bronchodilators in the treatment of obstructive lung diseases because they act via a different mechanism than β-agonists. The TAS2R signal transduction pathway in HASM has multiple elements that are potentially subject to regulation by inflammatory, genetic, and epigenetic mechanisms associated with asthma. To address this, expression, signaling, and physiologic functions of the three major TAS2Rs (subtypes 10, 14, and 31) on HASM were studied. Transcript expression of these TAS2Rs was not decreased in HASM cells derived from donors with asthma compared with those without asthma (n = 6 from each group). In addition, intracellular calcium ([Ca(2+)]i) signaling using TAS2R subtype-specific agonists (diphenhydramine, chloroquine, saccharin, and flufenamic acid) was not impaired in the cells derived from donors with asthma, nor was the response to quinine, which activates all three subtypes. HASM cell mechanics measured by magnetic twisting cytometry revealed equivalent TAS2R-mediated relaxation of methacholine-treated cells between the two groups. Human precision-cut lung slices treated with IL-13 caused a decrease in β-agonist (formoterol)-mediated relaxation of carbachol-contracted airways compared with control slices. In contrast, TAS2R-mediated relaxation was unaffected by IL-13. We conclude that TAS2R expression or function is unaffected in HASM cells derived from patients with asthma or the IL-13 inflammatory environment.
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Affiliation(s)
- Kathryn S Robinett
- 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, University of Maryland School of Medicine, Baltimore, Maryland
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28
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Chen Q, Zhang Y, Elad D, Jaffa AJ, Cao Y, Ye X, Duan E. Navigating the site for embryo implantation: Biomechanical and molecular regulation of intrauterine embryo distribution. Mol Aspects Med 2013; 34:1024-42. [DOI: 10.1016/j.mam.2012.07.017] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 07/31/2012] [Indexed: 01/03/2023]
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29
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Ehrlich AT, Furuyashiki T, Kitaoka S, Kakizuka A, Narumiya S. Prostaglandin E receptor EP1 forms a complex with dopamine D1 receptor and directs D1-induced cAMP production to adenylyl cyclase 7 through mobilizing G(βγ) subunits in human embryonic kidney 293T cells. Mol Pharmacol 2013; 84:476-86. [PMID: 23842570 DOI: 10.1124/mol.113.087288] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The mechanism underlying the crosstalk between multiple G protein-coupled receptors remains poorly understood. We previously reported that prostaglandin E receptor EP1 facilitates dopamine D1 receptor signaling in striatal slices and promotes behavioral responses induced by D1 receptor agonists. Here, using human embryonic kidney (HEK)-293T cells expressing D1 and EP1, we have analyzed the mechanism underlying EP1-mediated facilitation of D1 receptor signaling. Fluorescent immunostaining showed that EP1 and D1 receptors are partly colocalized in the cells, and coprecipitation experiments revealed a molecular complex of EP1 and D1 receptors. Treatment of the cells with 17S,17,20-dimethyl-2,5-ethano-6-oxo-PGE₁ (ONO-DI-004), an EP1-selective agonist, enhanced cAMP production induced by D1 agonists (±)-6-chloro-2,3,4,5-tetrahydro-1-phenyl-1H-3-benzazepine hydrobromide (SKF-81297) and 6-chloro-2,3,4,5-tetrahydro-1-(3-methylphenyl)-3-(2-propenyl)-1H-3-benzazepine-7,8-diol hydrobromide (SKF-83822). Although this facilitative effect of EP1 stimulation was not affected by pharmacologic blockade of EP1-induced Ca²⁺ increase, it was blocked by overexpression of G(tα) as a G(βγ) scavenger. Consistently, depletion of adenylyl cyclase (AC) 7, a G(βγ)-sensitive AC isoform, abolished the facilitative action of EP1 on D1-induced cAMP production. Notably, neither G(tα) overexpression nor AC7 depletion affected cAMP production induced by D1 stimulation alone. In contrast, depletion of AC6, another AC isoform, reduced cAMP production induced by D1 stimulation alone, but spared its facilitation by EP1 stimulation. Collectively, these data suggest that, through complex formation with D1, EP1 signaling directs the D1 receptor through G(βγ) to be coupled to AC7, an AC isoform distinct from those used by the D1 receptor alone, in HEK-293T cells.
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Affiliation(s)
- Aliza T Ehrlich
- Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
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30
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Abstract
INTRODUCTION There is an unmet need for a new class of direct bronchodilators for the treatment of asthma and chronic obstructive lung disease. Unexpectedly, bitter taste receptors (TAS2Rs) have been localized on airway smooth muscle and when activated cause marked smooth muscle relaxation through a mechanism that is distinct from β2-adrenegic receptors. Thus TAS2R agonists have emerged as a novel class of bronchodilator. AREAS COVERED A synopsis of the TAS2R family and its biology for bitter taste perception on the tongue is provided, followed by a review of the identification and molecular and physiological characterization of TAS2R subtypes on human and mouse airway smooth muscle. The proposed molecular mechanisms leading to the relaxation response are provided, along with gaps in our understanding at certain points in the signaling cascade. Unresolved issues that may need to be considered for drug development are discussed. EXPERT OPINION TAS2R agonists show promise as a new class of highly efficacious bronchodilators for treatment of obstructive lung disease. With tens of thousands of known natural and synthetic bitter compounds, there is substantial diversity within the known agonists, and, a ready source of agents for screening and further development of an inhaled TAS2R agonist for therapeutic purposes.
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Affiliation(s)
- Stephen B Liggett
- University of South Florida Morsani College of Medicine, Departments of Internal Medicine and Molecular Pharmacology and Physiology , 12901 Bruce B. Downs Blvd, MDC02 Tampa, FL 33612 , USA.
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31
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Refractoriness to exercise challenge: a review of the mechanisms old and new. Immunol Allergy Clin North Am 2013; 33:329-45, viii. [PMID: 23830128 DOI: 10.1016/j.iac.2013.02.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This article discusses the available literature on refractoriness in exercise-induced bronchoconstriction, namely, a decrease in airway responsiveness with repeated exercise challenges. The mechanisms of this naturally occurring protective feature is unknown. Reviewing previous studies together with findings in more recent studies, the authors propose desensitization of the G protein-coupled cysteinyl leukotriene receptor1 as the mechanism of refractoriness and that this desensitization occurs as a result of interplay between leukotrienes and prostaglandins.
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32
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Kawano K, Yano Y, Omae K, Matsuzaki S, Matsuzaki K. Stoichiometric analysis of oligomerization of membrane proteins on living cells using coiled-coil labeling and spectral imaging. Anal Chem 2013; 85:3454-61. [PMID: 23427815 DOI: 10.1021/ac400177a] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Many membrane proteins are proposed to work as oligomers; however, the conclusion is sometimes controversial, as for β2-adorenergic receptor (β2AR), which is one of the best-studied family A G-protein-coupled receptors. This is due to the lack of methods for easy and precise detection of the oligomeric state of membrane proteins on living cells. Here, we show that a combination of the coiled-coil tag-probe labeling method and spectral imaging enable a stoichiometric analysis of the oligomeric state of membrane proteins on living cells using monomeric, dimeric, and tetrameric standard membrane proteins. Using this method, we found that β2ARs do not form constitutive homooligomers, while they exhibit their functions such as the cyclic adenosine 5'-monophosphate (cAMP) signaling and internalization upon agonist stimulation.
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Affiliation(s)
- Kenichi Kawano
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
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33
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Alonso N, Fernandez N, Notcovich C, Monczor F, Simaan M, Baldi A, Gutkind JS, Davio C, Shayo C. Cross-desensitization and cointernalization of H1 and H2 histamine receptors reveal new insights into histamine signal integration. Mol Pharmacol 2013; 83:1087-98. [PMID: 23462507 DOI: 10.1124/mol.112.083394] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
G protein-coupled receptor signaling does not result from sequential activation of a linear pathway of proteins/enzymes, but rather from complex interactions of multiple, branched signaling routes, i.e., signaling networks. In this work we present an exhaustive study of the cross-talk between H1 and H2 histamine receptors (H1R and H2R) in U937 cells and Chinese hamster ovary-transfected cells. By desensitization assays we demonstrated the existence of a crossdesensitization between both receptors independent of protein kinase A or C. H1R-agonist stimulation inhibited cell proliferation and induced apoptosis in U937 cells following treatment of 48 hours. H1R-induced antiproliferative and apoptotic response was inhibited by an H2R agonist suggesting that the cross-talk between both receptors modifies their function. Binding and confocal microscopy studies revealed cointernalization of both receptors upon treatment with the agonists. To evaluate potential heterodimerization of the receptors, sensitized emission fluorescence resonance energy transfer experiments were performed in human embryonic kidney 293T cells using H1R-cyan fluorescent protein and H2R-yellow fluorescent protein. To our knowledge these findings may represent the first demonstration of agonist-induced heterodimerization of the H1R and H2R. In addition, we also show that the inhibition of the internalization process did not prevent receptor crossdesensitization, which was mediated by G protein-coupled receptor kinase 2. Our study provides new insights into the complex signaling network mediated by histamine and further knowledge for the rational use of its ligands.
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Affiliation(s)
- Natalia Alonso
- Laboratorio de Farmacología y Patología Molecular, Instituto de Biología y Medicina Experimental, Buenos Aires, Argentina
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34
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Billington CK, Ojo OO, Penn RB, Ito S. cAMP regulation of airway smooth muscle function. Pulm Pharmacol Ther 2013; 26:112-20. [PMID: 22634112 PMCID: PMC3574867 DOI: 10.1016/j.pupt.2012.05.007] [Citation(s) in RCA: 157] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/14/2012] [Accepted: 05/17/2012] [Indexed: 12/11/2022]
Abstract
Agonists activating β(2)-adrenoceptors (β(2)ARs) on airway smooth muscle (ASM) are the drug of choice for rescue from acute bronchoconstriction in patients with both asthma and chronic obstructive pulmonary disease (COPD). Moreover, the use of long-acting β-agonists combined with inhaled corticosteroids constitutes an important maintenance therapy for these diseases. β-Agonists are effective bronchodilators due primarily to their ability to antagonize ASM contraction. The presumed cellular mechanism of action involves the generation of intracellular cAMP, which in turn can activate the effector molecules cAMP-dependent protein kinase (PKA) and Epac. Other agents such as prostaglandin E(2) and phosphodiesterase inhibitors that also increase intracellular cAMP levels in ASM, can also antagonize ASM contraction, and inhibit other ASM functions including proliferation and migration. Therefore, β(2)ARs and cAMP are key players in combating the pathophysiology of airway narrowing and remodeling. However, limitations of β-agonist therapy due to drug tachyphylaxis related to β(2)AR desensitization, and recent findings regarding the manner in which β(2)ARs and cAMP signal, have raised new and interesting questions about these well-studied molecules. In this review we discuss current concepts regarding β(2)ARs and cAMP in the regulation of ASM cell functions and their therapeutic roles in asthma and COPD.
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Affiliation(s)
- Charlotte K Billington
- Division of Therapeutics and Molecular Medicine, The University of Nottingham, Nottingham NG7 2UH, UK.
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35
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Satake H, Matsubara S, Aoyama M, Kawada T, Sakai T. GPCR Heterodimerization in the Reproductive System: Functional Regulation and Implication for Biodiversity. Front Endocrinol (Lausanne) 2013; 4:100. [PMID: 23966979 PMCID: PMC3744054 DOI: 10.3389/fendo.2013.00100] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 07/31/2013] [Indexed: 01/24/2023] Open
Abstract
A G protein-coupled receptor (GPCR) functions not only as a monomer or homodimer but also as a heterodimer with another GPCR. GPCR heterodimerization results in the modulation of the molecular functions of the GPCR protomer, including ligand binding affinity, signal transduction, and internalization. There has been a growing body of reports on heterodimerization of multiple GPCRs expressed in the reproductive system and the resultant functional modulation, suggesting that GPCR heterodimerization is closely associated with reproduction including the secretion of hormones and the growth and maturation of follicles and oocytes. Moreover, studies on heterodimerization among paralogs of gonadotropin-releasing hormone (GnRH) receptors of a protochordate, Ciona intestinalis, verified the species-specific regulation of the functions of GPCRs via multiple GnRH receptor pairs. These findings indicate that GPCR heterodimerization is also involved in creating biodiversity. In this review, we provide basic and current knowledge regarding GPCR heterodimers and their functional modulation, and explore the biological significance of GPCR heterodimerization.
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Affiliation(s)
- Honoo Satake
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
- *Correspondence: Honoo Satake, Suntory Foundation for Life Sciences, Bioorganic Research Institute, 1-1-1 Wakayamadai, Shimamoto, Mishima, Osaka 618-8503, Japan e-mail:
| | - Shin Matsubara
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Masato Aoyama
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Tsuyoshi Kawada
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
| | - Tsubasa Sakai
- Suntory Foundation for Life Sciences, Bioorganic Research Institute, Osaka, Japan
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36
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Cotecchia S, Stanasila L, Diviani D. Protein-protein interactions at the adrenergic receptors. Curr Drug Targets 2012; 13:15-27. [PMID: 21777184 PMCID: PMC3290771 DOI: 10.2174/138945012798868489] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Revised: 02/12/2011] [Accepted: 02/16/2011] [Indexed: 01/07/2023]
Abstract
The adrenergic receptors are among the best characterized G protein-coupled receptors (GPCRs) and knowledge on this receptor family has provided several important paradigms about GPCR function and regulation. One of the most recent paradigms initially supported by studies on adrenergic receptors is that both βarrestins and G protein-coupled receptors themselves can act as scaffolds binding a variety of proteins and this can result in growing complexity of the receptor-mediated cellular effects. In this review we will briefly summarize the main features of βarrestin binding to the adrenergic receptor subtypes and we will review more in detail the main proteins found to selectively interact with distinct AR subtype. At the end, we will review the main findings on oligomerization of the AR subtypes.
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Affiliation(s)
- Susanna Cotecchia
- Départment de Pharmacologie et de Toxicologie, Université de Lausanne, Switzerland.
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37
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Pulkkinen V, Manson ML, Säfholm J, Adner M, Dahlén SE. The bitter taste receptor (TAS2R) agonists denatonium and chloroquine display distinct patterns of relaxation of the guinea pig trachea. Am J Physiol Lung Cell Mol Physiol 2012; 303:L956-66. [PMID: 22962016 DOI: 10.1152/ajplung.00205.2012] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Activation of taste receptors (TAS2Rs) by bitter taste agonists has been reported to cause bronchodilation. The aim of this study was to extend the information on the effects of bitter taste agonists on responses induced by different contractile mediators in a standard airway physiology preparation. Isometric responses were assessed in guinea pig trachea (GPT). TAS2R agonists were administered either to segments precontracted with different agonists for contraction or given before challenge with the different contractile stimuli, including antigen in tissues from ovalbumin-sensitized animals. TAS2R mRNA expression on GPT epithelium and smooth muscle was measured with real-time PCR. Denatonium, chloroquine, thiamine, and noscapine induced concentration-dependent relaxations (R(max): 98.3 ± 1.6, 100.0 ± 0.0, 100.0 ± 0.0, and 52.3 ± 1.1% of maximum, respectively, in the presence of indomethacin) in segments precontracted with carbachol. The receptors for denatonium (TAS2R4, TAS2R10) and chloroquine (TAS2R3, TAS2R10) were expressed in GPT. Whereas denatonium selectively inhibited contractions induced by carbachol, chloroquine uniformly inhibited contractions evoked by prostaglandin E(2), the thromboxane receptor agonist U-46619, leukotriene D(4), histamine, and antigen. The effects of denatonium, but not those of chloroquine, were partly inhibited by blockers of the large Ca(2+)-activated K(+) channels and decreased by an increase of the level of precontraction. In conclusion, TAS2R agonists mediated strong relaxations and substantial inhibition of contractions in GPT. Chloroquine and denatonium had distinct patterns of activity, indicating different signaling mechanisms. The findings reinforce the hypothesis that TAS2Rs are potential targets for the development of a new class of more efficacious agonists for bronchodilation.
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Affiliation(s)
- Ville Pulkkinen
- The Unit for Asthma and Allergy Research, the National Institute of Environmental Medicine and the Centre for Allergy Research, Karolinska Institutet, Stockholm, Sweden
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An SS, Wang WCH, Koziol-White CJ, Ahn K, Lee DY, Kurten RC, Panettieri RA, Liggett SB. TAS2R activation promotes airway smooth muscle relaxation despite β(2)-adrenergic receptor tachyphylaxis. Am J Physiol Lung Cell Mol Physiol 2012; 303:L304-11. [PMID: 22683571 DOI: 10.1152/ajplung.00126.2012] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recently, bitter taste receptors (TAS2Rs) were found in the lung and act to relax airway smooth muscle (ASM) via intracellular Ca(2+) concentration signaling generated from restricted phospholipase C activation. As potential therapy, TAS2R agonists could be add-on treatment when patients fail to achieve adequate bronchodilation with chronic β-agonists. The β(2)-adrenergic receptor (β(2)AR) of ASM undergoes extensive functional desensitization. It remains unknown whether this desensitization affects TAS2R function, by cross talk at the receptors or distal common components in the relaxation machinery. We studied intracellular signaling and cell mechanics using isolated human ASM, mouse tracheal responses, and human bronchial responses to characterize TAS2R relaxation in the context of β(2)AR desensitization. In isolated human ASM, magnetic twisting cytometry revealed >90% loss of isoproterenol-promoted decrease in cell stiffness after 18-h exposure to albuterol. Under these same conditions of β(2)AR desensitization, the TAS2R agonist chloroquine relaxation response was unaffected. TAS2R-mediated stimulation of intracellular Ca(2+) concentration in human ASM was unaltered by albuterol pretreatment, in contrast to cAMP signaling, which was desensitized by >90%. In mouse trachea, β(2)AR desensitization by β-agonist amounted to 92 ± 6.0% (P < 0.001), while, under these same conditions, TAS2R desensitization was not significant (11 ± 3.5%). In human lung slices, chronic β-agonist exposure culminated in 64 ± 5.7% (P < 0.001) desensitization of β(2)AR-mediated dilation of carbachol-constricted airways that was reversed by chloroquine. We conclude that there is no evidence for physiologically relevant cross-desensitization of TAS2R-mediated ASM relaxation from chronic β-agonist treatment. These findings portend a favorable therapeutic profile for TAS2R agonists for the treatment of bronchospasm in asthma or chronic obstructive lung disease.
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Affiliation(s)
- Steven S An
- Program in Respiratory Biology and Lung Disease, Johns Hopkins University, Bloomberg School of Public Health, 615 N Wolfe St., Rm. E-7616, Baltimore, MD 21205, USA.
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Cozzi R, Attanasio R. Octreotide long-acting repeatable for acromegaly. Expert Rev Clin Pharmacol 2012; 5:125-43. [PMID: 22390555 DOI: 10.1586/ecp.12.4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Acromegaly remains a therapeutic challenge for the endocrinologist. Among the available therapeutic options, octreotide long-acting repeatable (Sandostatin(®) LAR(®), Novartis) plays a chief role, both as a primary therapy and as an adjuvant treatment after unsuccessful surgery. A plethora of papers and a meta-analysis have demonstrated its efficacy in: control of clinical picture; achievement of safe growth hormone and normal age-matched IGF-I levels (both factors associated with restoration of normal life expectancy) in 60-70% of patients; control of tumor volume (with real shrinkage in over half of cases); and halt or reversal of most acromegaly-associated comorbidities. Treatment is well tolerated in most patients and can be safely prolonged for many years if required.
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Affiliation(s)
- Renato Cozzi
- Division of Endocrinology, Ospedale Niguarda, Via Canonica 81, I-20154 Milan, Italy.
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Somvanshi RK, Kumar U. Pathophysiology of GPCR Homo- and Heterodimerization: Special Emphasis on Somatostatin Receptors. Pharmaceuticals (Basel) 2012; 5:417-46. [PMID: 24281555 PMCID: PMC3763651 DOI: 10.3390/ph5050417] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 04/18/2012] [Accepted: 04/19/2012] [Indexed: 12/19/2022] Open
Abstract
G-protein coupled receptors (GPCRs) are cell surface proteins responsible for translating >80% of extracellular reception to intracellular signals. The extracellular information in the form of neurotransmitters, peptides, ions, odorants etc is converted to intracellular signals via a wide variety of effector molecules activating distinct downstream signaling pathways. All GPCRs share common structural features including an extracellular N-terminal, seven-transmembrane domains (TMs) linked by extracellular/intracellular loops and the C-terminal tail. Recent studies have shown that most GPCRs function as dimers (homo- and/or heterodimers) or even higher order of oligomers. Protein-protein interaction among GPCRs and other receptor proteins play a critical role in the modulation of receptor pharmacology and functions. Although ~50% of the current drugs available in the market target GPCRs, still many GPCRs remain unexplored as potential therapeutic targets, opening immense possibility to discover the role of GPCRs in pathophysiological conditions. This review explores the existing information and future possibilities of GPCRs as tools in clinical pharmacology and is specifically focused for the role of somatostatin receptors (SSTRs) in pathophysiology of diseases and as the potential candidate for drug discovery.
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Affiliation(s)
- Rishi K Somvanshi
- Faculty of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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Rediger A, Piechowski CL, Habegger K, Grüters A, Krude H, Tschöp MH, Kleinau G, Biebermann H. MC4R dimerization in the paraventricular nucleus and GHSR/MC3R heterodimerization in the arcuate nucleus: is there relevance for body weight regulation? Neuroendocrinology 2012; 95:277-88. [PMID: 22327910 DOI: 10.1159/000334903] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 11/06/2011] [Indexed: 01/21/2023]
Abstract
The worldwide obesity epidemic is increasing, yet at this time, no long-acting and specific pharmaceutical therapies are available. Peripheral hormonal signals communicate metabolic status to the hypothalamus by activating their corresponding receptors in the arcuate nucleus (ARC). In this brain region, a variety of G protein-coupled receptors (GPCRs) are expressed that are potentially involved in weight regulation, but so far, the detailed function of most hypothalamic GPCRs is only partially understood. An important and underappreciated feature of GPCRs is the capacity for regulation via di- and heterodimerization. Increasing evidence implicates that heterodimerization of GPCRs results in profound functional consequences. Recently, we could demonstrate that interaction of the melanocortin 3 receptor (MC3R) and the growth hormone secretagogue receptor (GHSR)-1a results in a modulation of function in both receptors. Although the physiological role of GPCR-GPCR interaction in the hypothalamus is yet to be elucidated, this concept promises new avenues for investigation and understanding of hypothalamic functions dependent on GPCR signaling. Since GPCRs are important targets for drugs to combat many diseases, identification of heterodimers may be a prerequisite for highly specific drugs. Therefore, a detailed understanding of the mechanisms and their involvement in weight regulation is necessary. Fundamental to this understanding is the interplay of GPCR-GPCR in the hypothalamic nuclei in energy metabolism. In this review, we summarize the current knowledge on melanocortin receptors and GHSR-1a in hypothalamic weight regulation, especially as they pertain to possible drug targets. Furthermore, we include available evidence for the participation and significance of GPCR dimerization.
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MESH Headings
- Animals
- Appetite Regulation/physiology
- Arcuate Nucleus of Hypothalamus/anatomy & histology
- Arcuate Nucleus of Hypothalamus/metabolism
- Arcuate Nucleus of Hypothalamus/physiology
- Body Weight/physiology
- Humans
- Models, Biological
- Paraventricular Hypothalamic Nucleus/anatomy & histology
- Paraventricular Hypothalamic Nucleus/metabolism
- Paraventricular Hypothalamic Nucleus/physiology
- Protein Multimerization/physiology
- Receptor, Melanocortin, Type 3/metabolism
- Receptor, Melanocortin, Type 3/physiology
- Receptor, Melanocortin, Type 4/metabolism
- Receptor, Melanocortin, Type 4/physiology
- Receptors, Ghrelin/metabolism
- Receptors, Ghrelin/physiology
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Affiliation(s)
- Anne Rediger
- Institute of Experimental Pediatric Endocrinology, Charité Universitätsmedizin Berlin, Humboldt University, Berlin, Germany
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Abstract
In almost 16 years since the word "dimer" was used in a publication to describe the organization of G protein-coupled receptors (GPCRs), a large number of studies have since weighed in on this notion. Are native, functional GPCRs monomers, dimers or as some would suggest even higher order structures? Here, we review some of the latest evidence regarding the organization of these receptors in both homo- and hetero-oligomeric formats, with a particular focus on β-adrenergic receptors. This is particularly important for understanding the allosteric nature of receptor/receptor interactions. It is likely that, over the course of evolution, mechanisms have come into play using all of the possible variations in receptor/receptor stoichiometry, depending on the cell and the physiological context in question. Finally, we provide some data that suggests that higher order structures of GPCRs, as with dimers themselves are probably assembled in the ER.
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Rediger A, Piechowski CL, Yi CX, Tarnow P, Strotmann R, Grüters A, Krude H, Schöneberg T, Tschöp MH, Kleinau G, Biebermann H. Mutually opposite signal modulation by hypothalamic heterodimerization of ghrelin and melanocortin-3 receptors. J Biol Chem 2011; 286:39623-31. [PMID: 21940628 PMCID: PMC3234785 DOI: 10.1074/jbc.m111.287607] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 09/03/2011] [Indexed: 12/22/2022] Open
Abstract
Interaction and cross-talk of G-protein-coupled receptors (GPCRs) are of considerable interest because an increasing number of examples implicate a profound functional and physiological relevance of homo- or hetero-oligomeric GPCRs. The ghrelin (growth hormone secretagogue receptor (GHSR)) and melanocortin-3 (MC3R) receptors are both known to have orexigenic effects on the hypothalamic control of body weight. Because in vitro studies indicate heterodimerization of GHSR and MC3R, we investigated their functional interplay. Combined in situ hybridization and immunohistochemistry indicated that the vast majority of GHSR-expressing neurons in the arcuate nucleus also express MC3R. In vitro coexpression of MC3R and GHSR promoted enhanced melanocortin-induced intracellular cAMP accumulation compared with activation of MC3R in the absence of GHSR. In contrast, agonist-independent basal signaling activity and ghrelin-induced signaling of GHSR were impaired, most likely due to interaction with MC3R. By taking advantage of naturally occurring GHSR mutations and an inverse agonist for GHSR, we demonstrate that the observed enhanced MC3R signaling capability depends directly on the basal activity of GHSR. In conclusion, we demonstrate a paradigm-shifting example of GPCR heterodimerization allowing for mutually opposite functional influence of two hypothalamic receptors controlling body weight. We found that the agonist-independent active conformation of one GPCR can determine the signaling modalities of another receptor in a heterodimer. Our discovery also implies that mutations within one of two interacting receptors might affect both receptors and different pathways simultaneously. These findings uncover mechanisms of important relevance for pharmacological targeting of GPCR in general and hypothalamic body weight regulation in particular.
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MESH Headings
- Animals
- Arcuate Nucleus of Hypothalamus/metabolism
- COS Cells
- Chlorocebus aethiops
- Cyclic AMP/genetics
- Cyclic AMP/metabolism
- Gene Expression Regulation/physiology
- Ghrelin/genetics
- Ghrelin/metabolism
- HEK293 Cells
- Humans
- Mice
- Mice, Knockout
- Mutation
- Nerve Tissue Proteins/agonists
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neurons/metabolism
- Protein Multimerization/physiology
- Receptor, Melanocortin, Type 3/agonists
- Receptor, Melanocortin, Type 3/genetics
- Receptor, Melanocortin, Type 3/metabolism
- Receptors, Ghrelin/agonists
- Receptors, Ghrelin/genetics
- Receptors, Ghrelin/metabolism
- Signal Transduction/physiology
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Affiliation(s)
- Anne Rediger
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Carolin L. Piechowski
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Chun-Xia Yi
- the Metabolic Diseases Institute, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio 45267, and
| | - Patrick Tarnow
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Rainer Strotmann
- the Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
| | - Annette Grüters
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Heiko Krude
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Torsten Schöneberg
- the Institute of Biochemistry, Medical Faculty, University of Leipzig, 04103 Leipzig, Germany
| | - Matthias H. Tschöp
- the Metabolic Diseases Institute, Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio 45267, and
| | - Gunnar Kleinau
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Heike Biebermann
- From the Institute of Experimental Pediatric Endocrinology, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany
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Ruan YC, Zhou W, Chan HC. Regulation of smooth muscle contraction by the epithelium: role of prostaglandins. Physiology (Bethesda) 2011; 26:156-70. [PMID: 21670162 DOI: 10.1152/physiol.00036.2010] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
As an analog to the endothelium situated next to the vascular smooth muscle, the epithelium is emerging as an important regulator of smooth muscle contraction in many vital organs/tissues by interacting with other cell types and releasing epithelium-derived factors, among which prostaglandins have been demonstrated to play a versatile role in governing smooth muscle contraction essential to the physiological and pathophysiological processes in a wide range of organ systems.
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Affiliation(s)
- Ye Chun Ruan
- School of Life Science, Sun Yat-sen University, China
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Functional interactions between the oxytocin receptor and the β2-adrenergic receptor: implications for ERK1/2 activation in human myometrial cells. Cell Signal 2011; 24:333-41. [PMID: 21964067 DOI: 10.1016/j.cellsig.2011.09.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 09/09/2011] [Accepted: 09/11/2011] [Indexed: 01/05/2023]
Abstract
The Gq-coupled oxytocin receptor (OTR) and the Gs-coupled β(2)-adrenergic receptor (β(2)AR) are both expressed in myometrial cells and mediate uterine contraction and relaxation, respectively. The two receptors represent important pharmacological targets as OTR antagonists and β(2)AR agonists are used to control pre-term uterine contractions. Despite their physiologically antagonistic effects, both receptors activate the MAP kinases ERK1/2, which has been implicated in uterine contraction and the onset of labor. To determine the signalling pathways involved in mediating the ERK1/2 response, we assessed the effect of blockers of specific G protein-associated pathways. In human myometrial hTERT-C3 cells, inhibition of Gαi as well as inhibition of the Gαq/PKC pathway led to a reduction of both OTR- and β(2)AR-mediated ERK1/2 activation. The involvement of Gαq/PKC in β(2)AR-mediated ERK1/2 induction was unexpected. To test whether the emergence of this novel signalling mechanism was dependent on OTR expression in the same cell, we conducted experiments in HEK 293 cells that were transfected with the β(2)AR alone or co-transfected with the OTR. Using this approach, we found that β(2)AR-mediated ERK1/2 responses became sensitive to PKC inhibition only in cells co-transfected with the OTR. Inhibitor studies indicated the involvement of an atypical PKC isoform in this process. We confirmed the specific involvement of PKCζ in this pathway by assessing PKCζ translocation to the cell membrane. Consistent with our inhibitor studies, we found that β(2)AR-mediated PKCζ translocation was dependent on co-expression of OTR. The present demonstration of a novel β(2)AR-coupled signalling pathway that is dependent on OTR co-expression is suggestive of a molecular interaction between the two receptors.
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Wrzal PK, Devost D, Pétrin D, Goupil E, Iorio-Morin C, Laporte SA, Zingg HH, Hébert TE. Allosteric interactions between the oxytocin receptor and the β2-adrenergic receptor in the modulation of ERK1/2 activation are mediated by heterodimerization. Cell Signal 2011; 24:342-50. [PMID: 21963428 DOI: 10.1016/j.cellsig.2011.09.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 09/09/2011] [Accepted: 09/11/2011] [Indexed: 12/22/2022]
Abstract
The oxytocin receptor (OTR) and the β(2)-adrenergic receptor (β(2)AR) are key regulators of uterine contraction. These two receptors are targets of tocolytic agents used to inhibit pre-term labor. Our recent study on the nature of OTR- and β(2)AR-mediated ERK1/2 activation in human hTERT-C3 myometrial cells suggested the presence of an OTR/β(2)AR hetero-oligomeric complex (see companion article). The goal of this study was to investigate potential allosteric interactions between OTR and β(2)AR and establish the nature of the interactions between these receptors in myometrial cells. We found that OTR-mediated ERK1/2 activation was attenuated significantly when cells were pretreated with the β(2)AR agonist isoproterenol or two antagonists, propranolol or timolol. In contrast, pretreatment of cells with a third β(2)AR antagonist, atenolol resulted in an increase in OTR-mediated ERK1/2 activation. Similarly, β(2)AR-mediated ERK1/2 activation was strongly attenuated by pretreatment with the OTR antagonists, atosiban and OTA. Physical interactions between OTR and β(2)AR were demonstrated using co-immunoprecipitation, bioluminescence resonance energy transfer (BRET) and protein-fragment complementation (PCA) assays in HEK 293 cells, the latter experiments indicating the interactions between the two receptors were direct. Our analyses suggest physical interactions between OTR and β(2)AR in the context of a new heterodimer pair lie at the heart of the allosteric effects.
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Affiliation(s)
- Paulina K Wrzal
- Department of Pharmacology and Therapeutics, McGill University, Montréal, Québec, Canada
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47
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Affiliation(s)
- Takako Hirata
- Department of Pharmacology, Kyoto University Graduate School of Medicine, Kyoto 606-8501, Japan
| | - Shuh Narumiya
- Department of Pharmacology, Kyoto University Graduate School of Medicine, Kyoto 606-8501, Japan
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Woodward DF, Jones RL, Narumiya S. International Union of Basic and Clinical Pharmacology. LXXXIII: classification of prostanoid receptors, updating 15 years of progress. Pharmacol Rev 2011; 63:471-538. [PMID: 21752876 DOI: 10.1124/pr.110.003517] [Citation(s) in RCA: 321] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
It is now more than 15 years since the molecular structures of the major prostanoid receptors were elucidated. Since then, substantial progress has been achieved with respect to distribution and function, signal transduction mechanisms, and the design of agonists and antagonists (http://www.iuphar-db.org/DATABASE/FamilyIntroductionForward?familyId=58). This review systematically details these advances. More recent developments in prostanoid receptor research are included. The DP(2) receptor, also termed CRTH2, has little structural resemblance to DP(1) and other receptors described in the original prostanoid receptor classification. DP(2) receptors are more closely related to chemoattractant receptors. Prostanoid receptors have also been found to heterodimerize with other prostanoid receptor subtypes and nonprostanoids. This may extend signal transduction pathways and create new ligand recognition sites: prostacyclin/thromboxane A(2) heterodimeric receptors for 8-epi-prostaglandin E(2), wild-type/alternative (alt4) heterodimers for the prostaglandin FP receptor for bimatoprost and the prostamides. It is anticipated that the 15 years of research progress described herein will lead to novel therapeutic entities.
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Affiliation(s)
- D F Woodward
- Dept. of Biological Sciences RD3-2B, Allergan, Inc., 2525 Dupont Dr., Irvine, CA 92612, USA.
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49
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Abstract
Prostaglandins are lipid autacoids derived from arachidonic acid. They both sustain homeostatic functions and mediate pathogenic mechanisms, including the inflammatory response. They are generated from arachidonate by the action of cyclooxygenase isoenzymes, and their biosynthesis is blocked by nonsteroidal antiinflammatory drugs, including those selective for inhibition of cyclooxygenase-2. Despite the clinical efficacy of nonsteroidal antiinflammatory drugs, prostaglandins may function in both the promotion and resolution of inflammation. This review summarizes insights into the mechanisms of prostaglandin generation and the roles of individual mediators and their receptors in modulating the inflammatory response. Prostaglandin biology has potential clinical relevance for atherosclerosis, the response to vascular injury and aortic aneurysm.
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Affiliation(s)
- Emanuela Ricciotti
- Institute for Translational Medicine and Therapeutics, 153 Johnson Pavilion, School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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50
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MicroRNA let-7 establishes expression of beta2-adrenergic receptors and dynamically down-regulates agonist-promoted down-regulation. Proc Natl Acad Sci U S A 2011; 108:6246-51. [PMID: 21447718 DOI: 10.1073/pnas.1101439108] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Although β(2)-adrenergic receptors (β(2)AR) are expressed on most cell types, mechanisms that establish expression levels and regulate expression by chronic agonist remain unclear. The 3' UTR of ADRB2 has a conserved 8-nucleotide seed region that we hypothesized is targeted by the let-7 family of miRNAs leading to translational repression. In luciferase assays with transfected cells, luc-β(2)WT3'UTR had decreased expression when cotransfected with let-7f, but a mutated luc-β(2)3'UTR lacking the seed was unaffected by let-7f; a mutated let-7f also had no effect on luc-β(2)WT3'UTR expression. ADRB2 mRNA was in greater abundance in immunoprecipitates of Ago2, a core component of the miRNA-induced silencing complex, when cells were transfected with let-7f, but not with a mutated let-7f, indicating a direct interaction with the silencing mechanism. H292 cells transfected with let-7f caused ∼60% decrease in native β(2)AR expression, but transfection with let-7f-specific locked nucleic acid anti-miRNA increased β(2)AR expression by ∼twofold. We considered that an increase in let-7f leading to greater repression of translation contributes to agonist-promoted down-regulation. Paradoxically, in cells and in lungs from mice treated in vivo, an ∼50% decrease in let-7f occurs during long-term agonist exposure, indicating a counterregulatory event. Consistent with this notion, let-7f locked nucleic acid transfection caused depressed agonist-promoted down-regulation. Thus, let-7f miRNA regulates baseline β(2)AR expression and decreases in let-7f evoked by agonist attenuate down-regulation. This positive feedback loop has not previously been described for a G protein-coupled receptor and its miRNA. Methods to decrease let-7f expression in targeted cells may increase therapeutic responses to β-agonist by increasing β(2)AR expression or minimizing tachyphylaxis.
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