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Korkutata M, Lazarus M. Adenosine A 2A receptors and sleep. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 170:155-178. [PMID: 37741690 DOI: 10.1016/bs.irn.2023.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/25/2023]
Abstract
Adenosine, a known endogenous somnogen, induces sleep via A1 and A2A receptors. In this chapter, we review the current knowledge regarding the role of the adenosine A2A receptor and its agonists, antagonists, and allosteric modulators in sleep-wake regulation. Although many adenosine A2A receptor agonists, antagonists, and allosteric modulators have been identified, only a few have been tested to see if they can promote sleep or wakefulness. In addition, the growing popularity of natural sleep aids has led to an investigation of natural compounds that may improve sleep by activating the adenosine A2A receptor. Finally, we discuss the potential therapeutic advantage of allosteric modulators of adenosine A2A receptors over classic agonists and antagonists for treating sleep and neurologic disorders.
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Affiliation(s)
- Mustafa Korkutata
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
| | - Michael Lazarus
- International Institute for Integrative Sleep Medicine (WPI-IIIS) and Institute of Medicine, University of Tsukuba, Tsukuba, Japan.
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2
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Korkutata M, Agrawal L, Lazarus M. Allosteric Modulation of Adenosine A 2A Receptors as a New Therapeutic Avenue. Int J Mol Sci 2022; 23:ijms23042101. [PMID: 35216213 PMCID: PMC8880556 DOI: 10.3390/ijms23042101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/11/2022] [Accepted: 02/11/2022] [Indexed: 12/26/2022] Open
Abstract
The therapeutic potential of targeting adenosine A2A receptors (A2ARs) is immense due to their broad expression in the body and central nervous system. The role of A2ARs in cardiovascular function, inflammation, sleep/wake behaviors, cognition, and other primary nervous system functions has been extensively studied. Numerous A2AR agonist and antagonist molecules are reported, many of which are currently in clinical trials or have already been approved for treatment. Allosteric modulators can selectively elicit a physiologic response only where and when the orthosteric ligand is released, which reduces the risk of an adverse effect resulting from A2AR activation. Thus, these allosteric modulators have a potential therapeutic advantage over classical agonist and antagonist molecules. This review focuses on the recent developments regarding allosteric A2AR modulation, which is a promising area for future pharmaceutical research because the list of existing allosteric A2AR modulators and their physiologic effects is still short.
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Affiliation(s)
- Mustafa Korkutata
- Department of Neurology, Division of Sleep Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA;
| | - Lokesh Agrawal
- Molecular Neuroscience Unit, Okinawa Institute of Science and Technology Graduate University, Kunigami-gun, Onna 904-0412, Japan;
| | - Michael Lazarus
- International Institute for Integrative Sleep Medicine (WPI-IIIS), University of Tsukuba, Tsukuba 305-8575, Japan
- Correspondence: ; Tel.: +81-29-853-3681
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Khanum G, Fatima A, Sharma P, Srivastava SK, Butcher RJ. Ethyl 2-amino-4-methylthiophene-3-carboxylate. IUCRDATA 2021; 6:x210351. [PMID: 36339105 PMCID: PMC9462330 DOI: 10.1107/s2414314621003515] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 04/01/2021] [Indexed: 11/25/2022] Open
Abstract
The title compound crystallizes with two molecules, A and B, in the asymmetric unit. Each molecule features an intramolecular N—H⋯O hydrogen bond and the same H atom is also involved in an intermolecular N—H⋯S bond to generate A + B dimers. Further N—H⋯O hydrogen bonds link the dimers into a [010] chain. The title compound, C8H11NO2S, crystallizes with two molecules, A and B, in the asymmetric unit. Each molecule features an intramolecular N—H⋯O hydrogen bond and the same H atom is also involved in an intermolecular N—H⋯S bond to generate A + B dimers. Further N—H⋯O hydrogen bonds link the dimers into a [010] chain.![]()
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Al-Shar'i NA, Al-Balas QA. Molecular Dynamics Simulations of Adenosine Receptors: Advances, Applications and Trends. Curr Pharm Des 2019; 25:783-816. [DOI: 10.2174/1381612825666190304123414] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 02/26/2019] [Indexed: 01/09/2023]
Abstract
:
Adenosine receptors (ARs) are transmembrane proteins that belong to the G protein-coupled receptors
(GPCRs) superfamily and mediate the biological functions of adenosine. To date, four AR subtypes are known,
namely A1, A2A, A2B and A3 that exhibit different signaling pathways, tissue localization, and mechanisms of
activation. Moreover, the widespread ARs and their implication in numerous physiological and pathophysiological
conditions had made them pivotal therapeutic targets for developing clinically effective agents.
:
The crystallographic success in identifying the 3D crystal structures of A2A and A1 ARs has dramatically enriched
our understanding of their structural and functional properties such as ligand binding and signal transduction.
This, in turn, has provided a structural basis for a larger contribution of computational methods, particularly molecular
dynamics (MD) simulations, toward further investigation of their molecular properties and designing
bioactive ligands with therapeutic potential. MD simulation has been proved to be an invaluable tool in investigating
ARs and providing answers to some critical questions. For example, MD has been applied in studying ARs
in terms of ligand-receptor interactions, molecular recognition, allosteric modulations, dimerization, and mechanisms
of activation, collectively aiding in the design of subtype selective ligands.
:
In this review, we focused on the advances and different applications of MD simulations utilized to study the
structural and functional aspects of ARs that can foster the structure-based design of drug candidates. In addition,
relevant literature was briefly discussed which establishes a starting point for future advances in the field of drug
discovery to this pivotal group of drug targets.
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Affiliation(s)
- Nizar A. Al-Shar'i
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
| | - Qosay A. Al-Balas
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
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Wold EA, Chen J, Cunningham KA, Zhou J. Allosteric Modulation of Class A GPCRs: Targets, Agents, and Emerging Concepts. J Med Chem 2019; 62:88-127. [PMID: 30106578 PMCID: PMC6556150 DOI: 10.1021/acs.jmedchem.8b00875] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
G-protein-coupled receptors (GPCRs) have been tractable drug targets for decades with over one-third of currently marketed drugs targeting GPCRs. Of these, the class A GPCR superfamily is highly represented, and continued drug discovery for this family of receptors may provide novel therapeutics for a vast range of diseases. GPCR allosteric modulation is an innovative targeting approach that broadens the available small molecule toolbox and is proving to be a viable drug discovery strategy, as evidenced by recent FDA approvals and clinical trials. Numerous class A GPCR allosteric modulators have been discovered recently, and emerging trends such as the availability of GPCR crystal structures, diverse functional assays, and structure-based computational approaches are improving optimization and development. This Perspective provides an update on allosterically targeted class A GPCRs and their disease indications and the medicinal chemistry approaches toward novel allosteric modulators and highlights emerging trends and opportunities in the field.
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Affiliation(s)
- Eric A. Wold
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jianping Chen
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Kathryn A. Cunningham
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jia Zhou
- Department of Pharmacology and Toxicology, Chemical Biology Program, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department of Pharmacology and Toxicology, Center for Addiction Research, University of Texas Medical Branch, Galveston, Texas 77555, United States
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Korkutata M, Saitoh T, Cherasse Y, Ioka S, Duo F, Qin R, Murakoshi N, Fujii S, Zhou X, Sugiyama F, Chen JF, Kumagai H, Nagase H, Lazarus M. Enhancing endogenous adenosine A2A receptor signaling induces slow-wave sleep without affecting body temperature and cardiovascular function. Neuropharmacology 2019; 144:122-132. [DOI: 10.1016/j.neuropharm.2018.10.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 10/10/2018] [Accepted: 10/14/2018] [Indexed: 01/20/2023]
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Sakkal LA, Rajkowski KZ, Armen RS. Prediction of consensus binding mode geometries for related chemical series of positive allosteric modulators of adenosine and muscarinic acetylcholine receptors. J Comput Chem 2017; 38:1209-1228. [PMID: 28130813 PMCID: PMC5403616 DOI: 10.1002/jcc.24728] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 11/29/2016] [Accepted: 12/20/2016] [Indexed: 12/13/2022]
Abstract
Following insights from recent crystal structures of the muscarinic acetylcholine receptor, binding modes of Positive Allosteric Modulators (PAMs) were predicted under the assumption that PAMs should bind to the extracellular surface of the active state. A series of well-characterized PAMs for adenosine (A1 R, A2A R, A3 R) and muscarinic acetylcholine (M1 R, M5 R) receptors were modeled using both rigid and flexible receptor CHARMM-based molecular docking. Studies of adenosine receptors investigated the molecular basis of the probe-dependence of PAM activity by modeling in complex with specific agonist radioligands. Consensus binding modes map common pharmacophore features of several chemical series to specific binding interactions. These models provide a rationalization of how PAM binding slows agonist radioligand dissociation kinetics. M1 R PAMs were predicted to bind in the analogous M2 R PAM LY2119620 binding site. The M5 R NAM (ML-375) was predicted to bind in the PAM (ML-380) binding site with a unique induced-fit receptor conformation. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Leon A. Sakkal
- Department of Pharmaceutical Sciences, College of Pharmacy, Thomas Jefferson University, 901 Walnut St. Suite 918. Philadelphia, PA 19170
| | - Kyle Z. Rajkowski
- Department of Pharmaceutical Sciences, College of Pharmacy, Thomas Jefferson University, 901 Walnut St. Suite 918. Philadelphia, PA 19170
| | - Roger S. Armen
- Department of Pharmaceutical Sciences, College of Pharmacy, Thomas Jefferson University, 901 Walnut St. Suite 918. Philadelphia, PA 19170
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Sun Y, Huang P. Adenosine A2B Receptor: From Cell Biology to Human Diseases. Front Chem 2016; 4:37. [PMID: 27606311 PMCID: PMC4995213 DOI: 10.3389/fchem.2016.00037] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 08/11/2016] [Indexed: 12/26/2022] Open
Abstract
Extracellular adenosine is a ubiquitous signaling molecule that modulates a wide array of biological processes. Recently, significant advances have been made in our understanding of A2B adenosine receptor (A2BAR). In this review, we first summarize some of the general characteristics of A2BAR, and then we describe the multiple binding partners of the receptor, such as newly identified α-actinin-1 and p105, and discuss how these associated proteins could modulate A2BAR's functions, including certain seemingly paradoxical functions of the receptor. Growing evidence indicates a critical role of A2BAR in cancer, renal disease, and diabetes, in addition to its importance in the regulation of vascular diseases, and lung disease. Here, we also discuss the role of A2BAR in cancer, renal disease, and diabetes and the potential of the receptor as a target for treating these three diseases.
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Affiliation(s)
- Ying Sun
- Department of Biology, South University of Science and Technology of ChinaShenzhen, China; Shenzhen Key Laboratory of Cell Microenvironment, South University of Science and Technology of ChinaShenzhen, China
| | - Pingbo Huang
- Division of Life Science, Hong Kong University of Science and TechnologyHong Kong, China; Division of Biomedical Engineering, Hong Kong University of Science and TechnologyHong Kong, China; State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and TechnologyHong Kong, China
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9
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Abstract
Adenosine is an ubiquitous nucleoside involved in various physiological and pathological functions by stimulating A1, A2A, A2B and A3 adenosine receptors (ARs). Allosteric enhancers to A1ARs may represent novel therapeutic agents because they increase the activity of these receptors by mediating a shift to their active form in the A1AR-G protein ternary complex. In this manner, they are able to amplify the action of endogenous adenosine, which is produced in high concentrations under conditions of metabolic stress. A1AR allosteric enhancers could be used as a justifiable alternative to the exogenous agonists that are characterized by receptor desensitization and downregulation. In this review, an analysis of some of the most interesting allosteric modulators of A1ARs has been reported.
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Synthesis and biological evaluation of a new series of 2-amino-3-aroyl thiophene derivatives as agonist allosteric modulators of the A1 adenosine receptor. A position-dependent effect study. Eur J Med Chem 2015; 101:185-204. [PMID: 26141910 DOI: 10.1016/j.ejmech.2015.06.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/05/2015] [Accepted: 06/22/2015] [Indexed: 11/20/2022]
Abstract
The 2-amino-3-(p-chlorobenzoyl)thiophene scaffold has been widely employed as a pharmacophore for the identification of small molecules acting as allosteric modulators at the adenosine A1 receptor. A new series of 2-amino-3-(p-chlorobenzoyl)-4-benzyl-5-arylthiophene derivatives, characterized by the absence as well as the presence of electron-releasing or electron-withdrawing groups on the phenyl ring at the 4- and 5-positions of the thiophene ring, were identified as positive allosteric enhancers at the adenosine A1 receptor in binding (saturation, competition and dissociation kinetics) and functional assays. To better understand the positional requirements of substituents on the 2-amino-3-(p-chlorobenzoyl)thiophene core, the corresponding regioisomeric 4-aryl-5-benzylthiophene analogues were synthesized and found to possess reduced allosteric enhancer activity.
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Romagnoli R, Baraldi PG, IJzerman AP, Massink A, Cruz-Lopez O, Lopez-Cara LC, Saponaro G, Preti D, Aghazadeh Tabrizi M, Baraldi S, Moorman AR, Vincenzi F, Borea PA, Varani K. Synthesis and Biological Evaluation of Novel Allosteric Enhancers of the A1 Adenosine Receptor Based on 2-Amino-3-(4′-Chlorobenzoyl)-4-Substituted-5-Arylethynyl Thiophene. J Med Chem 2014; 57:7673-86. [DOI: 10.1021/jm5008853] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Romeo Romagnoli
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Pier Giovanni Baraldi
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Adriaan P. IJzerman
- Leiden Academic
Centre for Drug Research, Division of Medicinal Chemistry, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Arnault Massink
- Leiden Academic
Centre for Drug Research, Division of Medicinal Chemistry, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Olga Cruz-Lopez
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Luisa Carlota Lopez-Cara
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Giulia Saponaro
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Delia Preti
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Mojgan Aghazadeh Tabrizi
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Stefania Baraldi
- Dipartimento
di Scienze Chimiche e Farmaceutiche, Università di Ferrara, Via Fossato
di Mortara 17-19, 44121 Ferrara, Italy
| | - Allan R. Moorman
- King Pharmaceuticals
Inc., Research and Development, 4000
CentreGreen Way, Suite 300, Cary, North Carolina 27513
| | - Fabrizio Vincenzi
- Dipartimento
di Scienze Mediche, Sezione di Farmacologia, Università di Ferrara, Via Savonarola 9, 44121 Ferrara, Italy
| | - Pier Andrea Borea
- Dipartimento
di Scienze Mediche, Sezione di Farmacologia, Università di Ferrara, Via Savonarola 9, 44121 Ferrara, Italy
| | - Katia Varani
- Dipartimento
di Scienze Mediche, Sezione di Farmacologia, Università di Ferrara, Via Savonarola 9, 44121 Ferrara, Italy
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Antonioli L, Csóka B, Fornai M, Colucci R, Kókai E, Blandizzi C, Haskó G. Adenosine and inflammation: what's new on the horizon? Drug Discov Today 2014; 19:1051-68. [DOI: 10.1016/j.drudis.2014.02.010] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/06/2014] [Accepted: 02/25/2014] [Indexed: 12/18/2022]
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Valant C, May LT, Aurelio L, Chuo CH, White PJ, Baltos JA, Sexton PM, Scammells PJ, Christopoulos A. Separation of on-target efficacy from adverse effects through rational design of a bitopic adenosine receptor agonist. Proc Natl Acad Sci U S A 2014; 111:4614-9. [PMID: 24619092 PMCID: PMC3970544 DOI: 10.1073/pnas.1320962111] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The concepts of allosteric modulation and biased agonism are revolutionizing modern approaches to drug discovery, particularly in the field of G protein-coupled receptors (GPCRs). Both phenomena exploit topographically distinct binding sites to promote unique GPCR conformations that can lead to different patterns of cellular responsiveness. The adenosine A1 GPCR (A1AR) is a major therapeutic target for cardioprotection, but current agents acting on the receptor are clinically limited for this indication because of on-target bradycardia as a serious adverse effect. In the current study, we have rationally designed a novel A1AR ligand (VCP746)--a hybrid molecule comprising adenosine linked to a positive allosteric modulator--specifically to engender biased signaling at the A1AR. We validate that the interaction of VCP746 with the A1AR is consistent with a bitopic mode of receptor engagement (i.e., concomitant association with orthosteric and allosteric sites) and that the compound displays biased agonism relative to prototypical A1AR ligands. Importantly, we also show that the unique pharmacology of VCP746 is (patho)physiologically relevant, because the compound protects against ischemic insult in native A1AR-expressing cardiomyoblasts and cardiomyocytes but does not affect rat atrial heart rate. Thus, this study provides proof of concept that bitopic ligands can be designed as biased agonists to promote on-target efficacy without on-target side effects.
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Affiliation(s)
- Celine Valant
- Drug Discovery Biology and Department of Pharmacology and
| | - Lauren T. May
- Drug Discovery Biology and Department of Pharmacology and
| | - Luigi Aurelio
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
| | - Chung Hui Chuo
- Drug Discovery Biology and Department of Pharmacology and
| | - Paul J. White
- Drug Discovery Biology and Department of Pharmacology and
| | - Jo-Anne Baltos
- Drug Discovery Biology and Department of Pharmacology and
| | | | - Peter J. Scammells
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC 3052, Australia
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Lenoir B, Wagner DR, Blacher S, Sala-Newby GB, Newby AC, Noel A, Devaux Y. Effects of adenosine on lymphangiogenesis. PLoS One 2014; 9:e92715. [PMID: 24651845 PMCID: PMC3961410 DOI: 10.1371/journal.pone.0092715] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 02/25/2014] [Indexed: 02/01/2023] Open
Abstract
Background The lymphatic system controls tissue homeostasis by draining protein-rich lymph to the vascular system. Lymphangiogenesis, the formation of lymphatic vessels, is a normal event in childhood but promotes tumor spread and metastasis during adulthood. Blocking lymphangiogenesis may therefore be of therapeutic interest. Production of adenosine is enhanced in the tumor environment and contributes to tumor progression through stimulation of angiogenesis. In this study, we determined whether adenosine affects lymphangiogenesis. Methods Lymphatic endothelial cells (HMVEC-dLy) were cultured in presence of adenosine and their proliferation, migration and tube formation was assessed. Gelatin sponges embedded with the stable analogue of adenosine 2-chloro adenosine were implanted in mice ear and lymphangiogenesis was quantified. Mice were intravenously injected with adenoviruses containing expression vector for 5′-endonucleotidase, which plays a major role in the formation of adenosine. Results In vitro, we observed that adenosine decreased the proliferation of lymphatic endothelial cells, their migration and tube formation. However, in vivo, gelatin sponges containing 2-chloro adenosine and implanted in mice ear displayed an elevated level of lymphangiogenesis (2.5-fold, p<0.001). Adenovirus-mediated over-expression of cytosolic 5′-nucleotidase IA stimulated lymphangiogenesis and the recruitment of macrophages in mouse liver. Proliferation of lymphatic endothelial cells was enhanced (2-fold, p<0.001) when incubated in the presence of conditioned medium from murine macrophages. Conclusion We have shown that adenosine stimulates lymphangiogenesis in vivo, presumably through a macrophage-mediated mechanism. This observation suggests that blockade of adenosine receptors may help in anti-cancer therapies.
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Affiliation(s)
- Bénédicte Lenoir
- Laboratory of Cardiovascular Research, Centre de Recherche Public de la Santé (CRP – Santé), Luxembourg
| | - Daniel R. Wagner
- Laboratory of Cardiovascular Research, Centre de Recherche Public de la Santé (CRP – Santé), Luxembourg
- Division of Cardiology, Centre Hospitalier Luxembourg, Luxembourg
| | - Silvia Blacher
- Laboratory of Tumor and Development Biology, Groupe Interdisciplinaire de Génoprotéomique Appliquée - Cancer, University of Liège, Liège, Belgium
| | - Graciela B. Sala-Newby
- Bristol Heart Institute, Bristol Royal Infirmary, University of Bristol, Bristol, United Kingdom
| | - Andrew C. Newby
- Bristol Heart Institute, Bristol Royal Infirmary, University of Bristol, Bristol, United Kingdom
| | - Agnès Noel
- Laboratory of Tumor and Development Biology, Groupe Interdisciplinaire de Génoprotéomique Appliquée - Cancer, University of Liège, Liège, Belgium
| | - Yvan Devaux
- Laboratory of Cardiovascular Research, Centre de Recherche Public de la Santé (CRP – Santé), Luxembourg
- * E-mail:
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15
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Trincavelli ML, Giacomelli C, Daniele S, Taliani S, Cosimelli B, Laneri S, Severi E, Barresi E, Pugliesi I, Greco G, Novellino E, Da Settimo F, Martini C. Allosteric modulators of human A2B adenosine receptor. Biochim Biophys Acta Gen Subj 2013; 1840:1194-203. [PMID: 24361612 DOI: 10.1016/j.bbagen.2013.12.021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 11/22/2013] [Accepted: 12/13/2013] [Indexed: 12/20/2022]
Abstract
BACKGROUND Among adenosine receptors (ARs) the A2B subtype exhibits low affinity for the endogenous agonist compared with the A1, A2A, and A3 subtypes and is therefore activated when concentrations of adenosine increase to a large extent following tissue damages (e.g. ischemia, inflammation). For this reason, A2B AR represents an important pharmacological target. METHODS We evaluated seven 1-benzyl-3-ketoindole derivatives (7-9) for their ability to act as positive or negative allosteric modulators of human A2B AR through binding and functional assays using CHO cells expressing human A1, A2A, A2B, and A3 ARs. RESULTS The investigated compounds behaved as specific positive or negative allosteric modulators of human A2B AR depending on small differences in their structures. The positive allosteric modulators 7a,b and 8a increased agonist efficacy without any effect on agonist potency. The negative allosteric modulators 8b,c and 9a,b reduced agonist potency and efficacy. CONCLUSIONS A number of 1-benzyl-3-ketoindole derivatives were pharmacologically characterized as selective positive (7a,b) or negative (8c, 9a,b) allosteric modulators of human A2B AR. GENERAL SIGNIFICANCE The 1-benzyl-3-ketoindole derivatives 7-9 acting as positive or negative allosteric modulators of human A2B AR represent new pharmacological tools useful for the development of therapeutic agents to treat pathological conditions related to an altered functionality of A2B AR.
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Affiliation(s)
| | - Chiara Giacomelli
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Simona Daniele
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Sabrina Taliani
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Barbara Cosimelli
- Dipartimento di Farmacia, Università di Napoli Federico II, Via Domenico Montesano 49, 80131 Napoli, Italy.
| | - Sonia Laneri
- Dipartimento di Farmacia, Università di Napoli Federico II, Via Domenico Montesano 49, 80131 Napoli, Italy
| | - Elda Severi
- Dipartimento di Farmacia, Università di Napoli Federico II, Via Domenico Montesano 49, 80131 Napoli, Italy
| | - Elisabetta Barresi
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Isabella Pugliesi
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Giovanni Greco
- Dipartimento di Farmacia, Università di Napoli Federico II, Via Domenico Montesano 49, 80131 Napoli, Italy.
| | - Ettore Novellino
- Dipartimento di Farmacia, Università di Napoli Federico II, Via Domenico Montesano 49, 80131 Napoli, Italy
| | - Federico Da Settimo
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
| | - Claudia Martini
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno Pisano 6, 56126 Pisa, Italy
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16
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Synthesis and biological evaluation of novel 2-amino-3-aroyl-4-neopentyl-5-substituted thiophene derivatives as allosteric enhancers of the A₁ adenosine receptor. Bioorg Med Chem 2013; 22:148-66. [PMID: 24332652 DOI: 10.1016/j.bmc.2013.11.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2013] [Accepted: 11/21/2013] [Indexed: 11/23/2022]
Abstract
2-Amino-3-benzoyl thiophenes have been widely reported to act as allosteric enhancers at the A1 adenosine receptor. Their activity can be increased considerably by appropriate substitutions at the 4- and 5-positions of the thiophene ring. Substituent size at the thiophene C-4 position seemed to be a factor closely related to activity, with the 4-neopentyl (2,2-dimethylpropyl) substitution showing the greatest enhanced activity. A wide series of 2-amino-3-aroyl-4-neopentylthiophene derivatives with general structure 3, characterized by the presence of different substituents (bromine, aryl and heteroaryl) at the 5-position of the thiophene ring, have been identified as potent AEs at the A1AR. With only one exception, all of the synthesized compounds proved to be superior to the reference compound PD 81,723 in a functional assay. Derivatives 3p, 3u, 3am, 3ap and 3ar were the most active compounds in binding (saturation and competition) and functional cAMP studies, being able to potentiate agonist [(3)H]CCPA binding to the A1 receptor.
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Key Words
- 2-Amino-3-benzoylthiophene
- 2-chloro-N(6)-cyclopentyladenosine
- A(1) adenosine receptor
- AE(s)
- Allosteric modulation
- CCPA
- CHO
- CNS
- CsF
- ERG
- EWG
- G protein-coupled receptors
- GPCRs
- N-bromosuccinimide
- NBS
- PdCl(2)(DPPF)
- [(3)H](4-(2-[7-amino-2-(2-furil)[1,2.4]triazolo[2,3-a][1,3,5]triazin-5-ylamino]ethyl)phenol)
- [(3)H]1,3-dipropyl-8-cyclopentyl-xanthine
- [(3)H]2-chloro-N(6)-cyclopentyladenosine
- [(3)H]5-N-(4-methoxyphenylcarbamoyl)amino-8-propyl-2-(2-furyl)pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine
- [(3)H]CCPA
- [(3)H]DPCPX
- [(3)H]MRE-3008F20
- [(3)H]ZM 241385
- [1,1′-bis(diphenylphosphino)ferrocene] dichloropalladium(II) complex with dichloromethane
- allosteric enhancer(s)
- cAMP
- central nervous system
- cesium fluoride
- chinese hamster ovary
- cyclic adenosine monophosphate
- electron-releasing group
- electron-withdrawing group
- hA(1)AR
- human A(1) adenosine receptor
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17
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Taliani S, Trincavelli ML, Cosimelli B, Laneri S, Severi E, Barresi E, Pugliesi I, Daniele S, Giacomelli C, Greco G, Novellino E, Martini C, Da Settimo F. Modulation of A2B adenosine receptor by 1-Benzyl-3-ketoindole derivatives. Eur J Med Chem 2013; 69:331-7. [PMID: 24077183 DOI: 10.1016/j.ejmech.2013.09.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 09/02/2013] [Indexed: 11/17/2022]
Abstract
We have disclosed a series of 1-benzyl-3-ketoindole derivatives acting as either positive or negative modulators of the human A(2B) adenosine receptor (A(2B) AR) depending on small differences in their side chain. The new compounds were designed taking into account structural similarities between AR antagonists and ligands of the GABA(A)/benzodiazepine receptor. All compounds resulted totally inactive at A(2A) and A₃ ARs and showed small (8a,b) or none (7a,b, 8c and 9a,b) affinity for A₁ AR. When tested on A(2B) AR-transfected CHO cells, 7a,b and 8a acted as positive modulators, whereas 8b,c and 9a,b acted as negative modulators, enhancing or weakening the NECA-induced increase of cAMP levels, respectively. Compounds 7-9 might be regarded as useful biological and pharmacological tools to explore the therapeutic potential of A(2B) AR modulators, while their 3-ketoindole scaffold might be taken as a reference to design new analogs.
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Affiliation(s)
- Sabrina Taliani
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
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18
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Romagnoli R, Baraldi PG, Carrion MD, Lopez Cara C, Kimatrai Salvador M, Preti D, Aghazadeh Tabrizi M, Moorman AR, Vincenzi F, Borea PA, Varani K. Synthesis and biological effects of novel 2-amino-3-(4-chlorobenzoyl)-4-substituted thiophenes as allosteric enhancers of the A1 adenosine receptor. Eur J Med Chem 2013; 67:409-27. [DOI: 10.1016/j.ejmech.2013.07.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 07/01/2013] [Accepted: 07/06/2013] [Indexed: 11/27/2022]
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Sachdeva S, Gupta M. Adenosine and its receptors as therapeutic targets: An overview. Saudi Pharm J 2013; 21:245-53. [PMID: 23960840 PMCID: PMC3744929 DOI: 10.1016/j.jsps.2012.05.011] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 05/31/2012] [Indexed: 12/14/2022] Open
Abstract
The main goal of the authors is to present an overview of adenosine and its receptors, which are G-protein coupled receptors. The four known adenosine receptor subtypes are discussed along with the therapeutic potential indicating that these receptors can serve as targets for various dreadful diseases.
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Affiliation(s)
| | - Monika Gupta
- ASBASJSM College of Pharmacy, Bela, Ropar, India
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20
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Kimatrai-Salvador M, Baraldi PG, Romagnoli R. Allosteric modulation of A1-adenosine receptor: a review. DRUG DISCOVERY TODAY. TECHNOLOGIES 2013; 10:e285-e296. [PMID: 24050280 DOI: 10.1016/j.ddtec.2012.08.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Allosteric modulators of adenosine receptors represent an alternative to direct-acting adenosine agonists and nucleoside uptake blockers, preferably those can selectively modulate the response to adenosine in only those organs or localized areas of a given organ in which production of adenosine is increased. Allosteric enhancers at the adenosine A1 receptor have received attention as anti-arrhythmic cardiac agents, and, more recently, as anti-lipolytic agents. In addition, this class of compounds has therapeutic potential as analgesics and neuroprotective agents.
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21
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Romagnoli R, Baraldi PG, Carrion MD, Cara CL, Cruz-Lopez O, Salvador MK, Preti D, Tabrizi MA, Moorman AR, Vincenzi F, Borea PA, Varani K. Synthesis and Biological Evaluation of 2-Amino-3-(4-chlorobenzoyl)-4-[(4-arylpiperazin-1-yl)methyl]-5-substituted-thiophenes. Effect of the 5-Modification on Allosteric Enhancer Activity at the A1 Adenosine Receptor. J Med Chem 2012; 55:7719-35. [DOI: 10.1021/jm3007504] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Romeo Romagnoli
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Pier Giovanni Baraldi
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Maria Dora Carrion
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Carlota Lopez Cara
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Olga Cruz-Lopez
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Maria Kimatrai Salvador
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Delia Preti
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Mojgan Aghazadeh Tabrizi
- Dipartimento di Scienze Chimiche
e Farmaceutiche, Università di Ferrara, Via Fossato di Mortara 17-19, 44121, Ferrara, Italy
| | - Allan R. Moorman
- Research and Development, King Pharmaceuticals Inc., 4000 CentreGreen Way, Suite
300, Cary, North Carolina, United States
| | - Fabrizio Vincenzi
- Dipartimento di Medicina Clinica
e Sperimentale, Sezione di Farmacologia, Università di Ferrara, Ferrara, Italy
| | - Pier Andrea Borea
- Dipartimento di Medicina Clinica
e Sperimentale, Sezione di Farmacologia, Università di Ferrara, Ferrara, Italy
| | - Katia Varani
- Dipartimento di Medicina Clinica
e Sperimentale, Sezione di Farmacologia, Università di Ferrara, Ferrara, Italy
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Allosteric modulators of rhodopsin-like G protein-coupled receptors: opportunities in drug development. Pharmacol Ther 2012; 135:292-315. [PMID: 22728155 DOI: 10.1016/j.pharmthera.2012.06.002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Accepted: 06/07/2012] [Indexed: 11/21/2022]
Abstract
Rhodopsin-like (class A) G protein-coupled receptors (GPCRs) are one of the most important classes of drug targets. The discovery that these GPCRs can be allosterically modulated by small drug molecules has opened up new opportunities in drug development. It will allow the drugability of "difficult targets", such as GPCRs activated by large (glyco)proteins, or by very polar or highly lipophilic physiological agonists. Receptor subtype selectivity should be more easily achievable with allosteric than with orthosteric ligands. Allosteric modulation will allow a broad spectrum of pharmacological effects largely expanding that of orthosteric ligands. Furthermore, allosteric modulators may show an improved safety profile as compared to orthosteric ligands. Only recently, the explicit search for allosteric modulators has been started for only a few rhodopsin-like GPCRs. The first negative allosteric modulators (allosteric antagonists) of chemokine receptors, maraviroc (CCR5 receptor), used in HIV therapy, and plerixafor (CXCR4 receptor) for stem cell mobilization, have been approved as drugs. The development of allosteric modulators for rhodopsin-like GPCRs as novel drugs is still at an early stage; it appears highly promising.
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23
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Jacobson KA, Gao ZG, Göblyös A, IJzerman AP. Allosteric modulation of purine and pyrimidine receptors. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2011; 61:187-220. [PMID: 21586360 PMCID: PMC3165024 DOI: 10.1016/b978-0-12-385526-8.00007-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Among the purine and pyrimidine receptors, the discovery of small molecular allosteric modulators has been most highly advanced for the A(1) and A(3) adenosine receptors (ARs). These AR modulators have allosteric effects that are structurally separated from the orthosteric effects in SAR studies. The benzoylthiophene derivatives tend to act as allosteric agonists as well as selective positive allosteric modulators (PAMs) of the A(1) AR. A 2-amino-3-aroylthiophene derivative T-62 has been under development as a PAM of the A(1) AR for the treatment of chronic pain. Several structurally distinct classes of allosteric modulators of the human A(3) AR have been reported: 3-(2-pyridinyl)isoquinolines, 2,4-disubstituted quinolines, 1H-imidazo-[4,5-c]quinolin-4-amines, endocannabinoid 2-arachidonylglycerol, and the food dye Brilliant Black BN. Site-directed mutagenesis of A(1) and A(3) ARs has identified residues associated with the allosteric effect, distinct from those that affect orthosteric binding. A few small molecular allosteric modulators have been reported for several of the P2X ligand-gated ion channels and the G protein-coupled P2Y receptor nucleotides. Metal ion modulation of the P2X receptors has been extensively explored. The allosteric approach to modulation of purine and pyrimidine receptors looks promising for development of drugs that are event and site specific in action.
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Affiliation(s)
- Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Zhan-Guo Gao
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Anikó Göblyös
- Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden University, P.O. Box 9502, 2300 RA, Leiden, The Netherlands
| | - Adriaan P. IJzerman
- Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden University, P.O. Box 9502, 2300 RA, Leiden, The Netherlands
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24
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Press NJ, Fozard JR. Progress towards novel adenosine receptor therapeutics gleaned from the recent patent literature. Expert Opin Ther Pat 2010; 20:987-1005. [DOI: 10.1517/13543776.2010.495388] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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25
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De Amici M, Dallanoce C, Holzgrabe U, Tränkle C, Mohr K. Allosteric ligands for G protein-coupled receptors: a novel strategy with attractive therapeutic opportunities. Med Res Rev 2010; 30:463-549. [PMID: 19557759 DOI: 10.1002/med.20166] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Allosteric receptor ligands bind to a recognition site that is distinct from the binding site of the endogenous messenger molecule. As a consequence, allosteric agents may attach to receptors that are already transmitter-bound. Ternary complex formation opens an avenue to qualitatively new drug actions at G protein-coupled receptors (GPCRs), in particular receptor subtype selective potentiation of endogenous transmitter action. Consequently, suitable exploitation of allosteric recognition sites as alternative molecular targets could pave the way to a drug discovery paradigm different from those aimed at mimicking or blocking the effects of endogenous (orthosteric) receptor activators. The number of allosteric ligands reported to modulate GPCR function is steadily increasing and some have already reached routine clinical use. This review aims at introducing into this fascinating field of drug discovery and at providing an overview about the achievements that have already been made. Various case examples will be discussed in the framework of GPCR classification (family A, B, and C receptors). In addition, the behavior at muscarinic receptors of hybrid derivatives incorporating both an allosteric and an orthosteric fragment in a common molecular skeleton will be illustrated.
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Affiliation(s)
- Marco De Amici
- Department of Pharmaceutical Sciences Pietro Pratesi, University of Milan, via Mangiagalli 25, 20133 Milano, Italy.
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26
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Göblyös A, Ijzerman AP. Allosteric modulation of adenosine receptors. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1808:1309-18. [PMID: 20599682 DOI: 10.1016/j.bbamem.2010.06.013] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Revised: 06/10/2010] [Accepted: 06/10/2010] [Indexed: 10/19/2022]
Abstract
Allosteric ligands for G protein-coupled receptors (GPCRs) may alter receptor conformations induced by an orthosteric ligand. These modulators can thus fine-tune classical pharmacological responses. In this review we will describe efforts to synthesize and characterize allosteric modulators for one particular GPCR subfamily, the adenosine receptors. There are four subtypes of these receptors: A(1), A(2A), A(2B) and A(3). Allosteric enhancers for the adenosine A(1) receptor may have anti-arrythmic and anti-lipolytic activity. They may also act as analgesics and neuroprotective agents. A(3) allosteric enhancers are thought to be beneficial in ischemic conditions or as antitumor agents. We will summarize recent developments regarding the medicinal chemistry of such compounds. Most data have been and are published about the adenosine A(1) and A(3) receptor, whereas limited or no information is available for the A(2A) and A(2B) receptor, respectively. Receptor mutation studies are also discussed, as they may shed light on the localization of the allosteric binding sites. This article is part of a Special Issue entitled: "Adenosine Receptors".
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Affiliation(s)
- Anikó Göblyös
- Leiden/Amsterdam Center for Drug Research, Division of Medicinal Chemistry, Leiden, The Netherlands
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