1
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Hovah ME, Holzgrabe U. Bivalent and bitopic ligands of the opioid receptors: The prospects of a dual approach. Med Res Rev 2024; 44:2545-2599. [PMID: 38751227 DOI: 10.1002/med.22050] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 04/09/2024] [Accepted: 05/05/2024] [Indexed: 10/05/2024]
Abstract
Opioid receptors belonging to the class A G-protein coupled receptors (GPCRs) are the targets of choice in the treatment of acute and chronic pain. However, their on-target side effects such as respiratory depression, tolerance and addiction have led to the advent of the 'opioid crisis'. In the search for safer analgesics, bivalent and more recently, bitopic ligands have emerged as valuable tool compounds to probe these receptors. The activity of bivalent and bitopic ligands rely greatly on the allosteric nature of the GPCRs. Bivalent ligands consist of two pharmacophores, each binding to the individual orthosteric binding site (OBS) of the monomers within a dimer. Bitopic or dualsteric ligands bridge the gap between the OBS and the spatially distinct, less conserved allosteric binding site (ABS) through the simultaneous occupation of these two sites. Bivalent and bitopic ligands stabilize distinct conformations of the receptors which ultimately translates into unique signalling and pharmacological profiles. Some of the interesting properties shown by these ligands include improved affinity and/or efficacy, subtype and/or functional selectivity and reduced side effects. This review aims at providing an overview of some of the bivalent and bitopic ligands of the opioid receptors and, their pharmacology in the hope of inspiring the design and discovery of the next generation of opioid analgesics.
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Affiliation(s)
- Marie Emilie Hovah
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, Wuerzburg, Germany
| | - Ulrike Holzgrabe
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, Wuerzburg, Germany
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2
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Cheng L, Miao Z, Liu S, Li Z, Fu H, Xu C, Hu S, Zhao C, Liu Y, Zhao T, Liu W, Wang H, Liu R, Yan W, Tang X, Liu J, Shao Z, Ke B. Cryo-EM structure of small-molecule agonist bound delta opioid receptor-G i complex enables discovery of biased compound. Nat Commun 2024; 15:8284. [PMID: 39333070 PMCID: PMC11437176 DOI: 10.1038/s41467-024-52601-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 09/12/2024] [Indexed: 09/29/2024] Open
Abstract
Delta opioid receptor (δOR) plays a pivotal role in modulating human sensation and emotion. It is an attractive target for drug discovery since, unlike Mu opioid receptor, it is associated with low risk of drug dependence. Despite its potential applications, the pharmacological properties of δOR, including the mechanisms of activation by small-molecule agonists and the complex signaling pathways it engages, as well as their relation to the potential side effects, remain poorly understood. In this study, we use cryo-electron microscopy (cryo-EM) to determine the structure of the δOR-Gi complex when bound to a small-molecule agonist (ADL5859). Moreover, we design a series of probes to examine the key receptor-ligand interaction site and identify a region involved in signaling bias. Using ADL06 as a chemical tool, we elucidate the relationship between the β-arrestin pathway of the δOR and its biological functions, such as analgesic tolerance and convulsion activities. Notably, we discover that the β-arrestin recruitment of δOR might be linked to reduced gastrointestinal motility. These insights enhance our understanding of δOR's structure, signaling pathways, and biological functions, paving the way for the structure-based drug discovery.
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Grants
- 2023ZYD0168 Department of Science and Technology of Sichuan Province (Sichuan Provincial Department of Science and Technology)
- 2024NSFJQ0052 Department of Science and Technology of Sichuan Province (Sichuan Provincial Department of Science and Technology)
- 82425054, 82273784 National Natural Science Foundation of China (National Science Foundation of China)
- 82271190, 32100965 National Natural Science Foundation of China (National Science Foundation of China)
- 323B2038 National Natural Science Foundation of China (National Science Foundation of China)
- 32371288, 32100988 National Natural Science Foundation of China (National Science Foundation of China)
- 31972916, T2221004, 31972916 National Natural Science Foundation of China (National Science Foundation of China)
- 32330049, 82320108021 National Natural Science Foundation of China (National Science Foundation of China)
- 2019YFA0508800 Ministry of Science,Technology and Research (Ministry of Technology & Research)
- 2021ZD0201900 Ministry of Science and Technology of the People's Republic of China (Chinese Ministry of Science and Technology)
- the 1.3.5 Project for Disciplines of Excellence, West China Hospital, Sichuan University,ZYYC21002 and ZYGD23025
- Ministry of Science,Technology and Research (Ministry of Technology & Research)
- Frontiers Medical Center, Tianfu Jincheng Laboratory Foundation, TFJC2023010010; the 1.3.5 Project for Disciplines of Excellence, West China Hospital, Sichuan University, ZYYC20023.
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Affiliation(s)
- Lin Cheng
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Department of Otolaryngology Head and Neck Surgery, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, Sichuan, China
| | - Zhuang Miao
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Sicen Liu
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Frontiers Medical Center, Tianfu Jincheng Laboratory, Chengdu, China
| | - Zhe Li
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, P. R. China
| | - Hong Fu
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Chanjuan Xu
- Cellular Signaling Laboratory, International Research Center for Sensory Biology and Technology of MOST, Key Laboratory of Molecular Biophysics of MOE, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Shilong Hu
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Chang Zhao
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Yuxuan Liu
- Cellular Signaling Laboratory, International Research Center for Sensory Biology and Technology of MOST, Key Laboratory of Molecular Biophysics of MOE, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Tiantian Zhao
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Wencheng Liu
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Heli Wang
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Runduo Liu
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, P. R. China
| | - Wei Yan
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Xiangdong Tang
- Sleep Medicine Center, Mental Health Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Jianfeng Liu
- Cellular Signaling Laboratory, International Research Center for Sensory Biology and Technology of MOST, Key Laboratory of Molecular Biophysics of MOE, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, China.
| | - Zhenhua Shao
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
- Division of Nephrology and Kidney Research Institute, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
- Frontiers Medical Center, Tianfu Jincheng Laboratory, Chengdu, China.
| | - Bowen Ke
- Department of Anesthesiology, Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
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3
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Morales P, Scharf MM, Bermudez M, Egyed A, Franco R, Hansen OK, Jagerovic N, Jakubík J, Keserű GM, Kiss DJ, Kozielewicz P, Larsen O, Majellaro M, Mallo-Abreu A, Navarro G, Prieto-Díaz R, Rosenkilde MM, Sotelo E, Stark H, Werner T, Wingler LM. Progress on the development of Class A GPCR-biased ligands. Br J Pharmacol 2024. [PMID: 39261899 DOI: 10.1111/bph.17301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 05/06/2024] [Accepted: 05/18/2024] [Indexed: 09/13/2024] Open
Abstract
Class A G protein-coupled receptors (GPCRs) continue to garner interest for their essential roles in cell signalling and their importance as drug targets. Although numerous drugs in the clinic target these receptors, over 60% GPCRs remain unexploited. Moreover, the adverse effects triggered by the available unbiased GPCR modulators, limit their use and therapeutic value. In this context, the elucidation of biased signalling has opened up new pharmacological avenues holding promise for safer therapeutics. Functionally selective ligands favour receptor conformations facilitating the recruitment of specific effectors and the modulation of the associated pathways. This review surveys the current drug discovery landscape of GPCR-biased modulators with a focus on recent advances. Understanding the biological effects of this preferential coupling is at different stages depending on the Class A GPCR family. Therefore, with a focus on individual GPCR families, we present a compilation of the functionally selective modulators reported over the past few years. In doing so, we dissect their therapeutic relevance, molecular determinants and potential clinical applications.
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Affiliation(s)
- Paula Morales
- Instituto de Química Médica, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Magdalena M Scharf
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Marcel Bermudez
- Institute for Pharmaceutical and Medicinal Chemistry, University of Münster, Münster, Germany
| | - Attila Egyed
- Medicinal Chemistry Research Group and National Drug Discovery and Development Laboratory, Research Centre for Natural Sciences, Budapest, Hungary
| | - Rafael Franco
- Molecular Neurobiology Laboratory, Department of Biochemistry and Molecular Biology, Universitat de Barcelona, Barcelona, Spain
- CiberNed. Network Center for Neurodegenerative Diseases, National Spanish Health Institute Carlos III, Madrid, Spain
- School of Chemistry, Universitat de Barcelona, Barcelona, Spain
| | - Olivia K Hansen
- Laboratory of Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nadine Jagerovic
- Instituto de Química Médica, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Jan Jakubík
- Institute of Physiology Czech Academy of Sciences, Prague, Czech Republic
| | - György M Keserű
- Medicinal Chemistry Research Group and National Drug Discovery and Development Laboratory, Research Centre for Natural Sciences, Budapest, Hungary
| | - Dóra Judit Kiss
- Medicinal Chemistry Research Group and National Drug Discovery and Development Laboratory, Research Centre for Natural Sciences, Budapest, Hungary
| | - Pawel Kozielewicz
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Olav Larsen
- Laboratory of Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Ana Mallo-Abreu
- Center for Research in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Santiago de Compostela, Spain
- Laboratory of Medicinal Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, Universitat de Barcelona, Barcelona, Spain
- Institute of Biomedicine (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Gemma Navarro
- CiberNed. Network Center for Neurodegenerative Diseases, National Spanish Health Institute Carlos III, Madrid, Spain
- Department of Biochemistry and Physiology, Faculty of Pharmacy and Food Science, Universitat de Barcelona, Barcelona, Spain
| | - Rubén Prieto-Díaz
- Center for Research in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Mette M Rosenkilde
- Laboratory of Molecular Pharmacology, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Eddy Sotelo
- Center for Research in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Holger Stark
- Heinrich Heine University Düsseldorf, Institut fuer Pharmazeutische und Medizinische Chemie, Duesseldorf, Germany
| | - Tobias Werner
- Heinrich Heine University Düsseldorf, Institut fuer Pharmazeutische und Medizinische Chemie, Duesseldorf, Germany
| | - Laura M Wingler
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina, USA
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4
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Ople R, Ramos-Gonzalez N, Li Q, Sobecks BL, Aydin D, Powers AS, Faouzi A, Polacco BJ, Bernhard SM, Appourchaux K, Sribhashyam S, Eans SO, Tsai BA, Dror RO, Varga BR, Wang H, Hüttenhain R, McLaughlin JP, Majumdar S. Signaling Modulation Mediated by Ligand Water Interactions with the Sodium Site at μOR. ACS CENTRAL SCIENCE 2024; 10:1490-1503. [PMID: 39220695 PMCID: PMC11363324 DOI: 10.1021/acscentsci.4c00525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 09/04/2024]
Abstract
The mu opioid receptor (μOR) is a target for clinically used analgesics. However, adverse effects, such as respiratory depression and physical dependence, necessitate the development of alternative treatments. Recently we reported a novel strategy to design functionally selective opioids by targeting the sodium binding allosteric site in μOR with a supraspinally active analgesic named C6guano. Presently, to improve systemic activity of this ligand, we used structure-based design, identifying a new ligand named RO76 where the flexible alkyl linker and polar guanidine guano group is swapped with a benzyl alcohol, and the sodium site is targeted indirectly through waters. A cryoEM structure of RO76 bound to the μOR-Gi complex confirmed that RO76 interacts with the sodium site residues through a water molecule, unlike C6guano which engages the sodium site directly. Signaling assays coupled with APEX based proximity labeling show binding in the sodium pocket modulates receptor efficacy and trafficking. In mice, RO76 was systemically active in tail withdrawal assays and showed reduced liabilities compared to those of morphine. In summary, we show that targeting water molecules in the sodium binding pocket may be an avenue to modulate signaling properties of opioids, and which may potentially be extended to other G-protein coupled receptors where this site is conserved.
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Affiliation(s)
- Rohini
S. Ople
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Nokomis Ramos-Gonzalez
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Qiongyu Li
- Department
of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, California 94158, United States
| | - Briana L. Sobecks
- Department of Computer Science, Stanford
University, Stanford, California 94305, United States
- Department
of Structural Biology, Stanford University
School of Medicine, Stanford, California 94305, United States
- Department
of Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Deniz Aydin
- Department of Computer Science, Stanford
University, Stanford, California 94305, United States
- Department
of Structural Biology, Stanford University
School of Medicine, Stanford, California 94305, United States
- Department
of Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Alexander S. Powers
- Department of Computer Science, Stanford
University, Stanford, California 94305, United States
- Department
of Structural Biology, Stanford University
School of Medicine, Stanford, California 94305, United States
- Department
of Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Abdelfattah Faouzi
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Benjamin J. Polacco
- Department of Computer Science, Stanford
University, Stanford, California 94305, United States
- Department
of Structural Biology, Stanford University
School of Medicine, Stanford, California 94305, United States
| | - Sarah M. Bernhard
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Kevin Appourchaux
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Sashrik Sribhashyam
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Shainnel O. Eans
- Department
of Pharmacodynamics, University of Florida, Gainesville, Florida 032610, United
States
| | - Bowen A. Tsai
- Department
of Pharmacodynamics, University of Florida, Gainesville, Florida 032610, United
States
| | - Ron O. Dror
- Department of Computer Science, Stanford
University, Stanford, California 94305, United States
- Department
of Structural Biology, Stanford University
School of Medicine, Stanford, California 94305, United States
- Department
of Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Balazs R. Varga
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Haoqing Wang
- Department
of Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Ruth Hüttenhain
- Department
of Molecular & Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305, United States
| | - Jay P. McLaughlin
- Department
of Pharmacodynamics, University of Florida, Gainesville, Florida 032610, United
States
| | - Susruta Majumdar
- Center
for Clinical Pharmacology, University of
Health Sciences & Pharmacy at St. Louis and Washington University
School of Medicine, St. Louis, Missouri 63110, United States
- Department
of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, St. Louis, Missouri 63110, United States
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5
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Yuan Y, Xu T, Huang Y, Shi J. Strategies for developing μ opioid receptor agonists with reduced adverse effects. Bioorg Chem 2024; 149:107507. [PMID: 38850778 DOI: 10.1016/j.bioorg.2024.107507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 05/02/2024] [Accepted: 05/28/2024] [Indexed: 06/10/2024]
Abstract
Opioids are currently the most effective and widely used painkillers in the world. Unfortunately, the clinical use of opioid analgesics is limited by serious adverse effects. Many researchers have been working on designing and optimizing structures in search of novel μ opioid receptor(MOR) agonists with improved analgesic activity and reduced incidence of adverse effects. There are many strategies to develop MOR drugs, mainly focusing on new low efficacy agonists (potentially G protein biased agonists), MOR agonists acting on different Gα subtype, targeting opioid receptors in the periphery, acting on multiple opioid receptor, and targeting allosteric sites of opioid receptors, and others. This review summarizes the design methods, clinical applications, and structure-activity relationships of small-molecule agonists for MOR based on these different design strategies, providing ideas for the development of safer novel opioid ligands with therapeutic potential.
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Affiliation(s)
- Yan Yuan
- College of Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 611756, China
| | - Ting Xu
- Department of Anesthesiology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan 610072, China
| | - Yu Huang
- College of Life Science and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 611756, China
| | - Jianyou Shi
- Department of Pharmacy, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Academy of Medical Science & Sichuan Provincial People's Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610072, China.
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6
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O'Brien ES, Rangari VA, El Daibani A, Eans SO, Hammond HR, White E, Wang H, Shiimura Y, Krishna Kumar K, Jiang Q, Appourchaux K, Huang W, Zhang C, Kennedy BJ, Mathiesen JM, Che T, McLaughlin JP, Majumdar S, Kobilka BK. A µ-opioid receptor modulator that works cooperatively with naloxone. Nature 2024; 631:686-693. [PMID: 38961287 DOI: 10.1038/s41586-024-07587-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 05/21/2024] [Indexed: 07/05/2024]
Abstract
The µ-opioid receptor (µOR) is a well-established target for analgesia1, yet conventional opioid receptor agonists cause serious adverse effects, notably addiction and respiratory depression. These factors have contributed to the current opioid overdose epidemic driven by fentanyl2, a highly potent synthetic opioid. µOR negative allosteric modulators (NAMs) may serve as useful tools in preventing opioid overdose deaths, but promising chemical scaffolds remain elusive. Here we screened a large DNA-encoded chemical library against inactive µOR, counter-screening with active, G-protein and agonist-bound receptor to 'steer' hits towards conformationally selective modulators. We discovered a NAM compound with high and selective enrichment to inactive µOR that enhances the affinity of the key opioid overdose reversal molecule, naloxone. The NAM works cooperatively with naloxone to potently block opioid agonist signalling. Using cryogenic electron microscopy, we demonstrate that the NAM accomplishes this effect by binding a site on the extracellular vestibule in direct contact with naloxone while stabilizing a distinct inactive conformation of the extracellular portions of the second and seventh transmembrane helices. The NAM alters orthosteric ligand kinetics in therapeutically desirable ways and works cooperatively with low doses of naloxone to effectively inhibit various morphine-induced and fentanyl-induced behavioural effects in vivo while minimizing withdrawal behaviours. Our results provide detailed structural insights into the mechanism of negative allosteric modulation of the µOR and demonstrate how this can be exploited in vivo.
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MESH Headings
- Animals
- Humans
- Male
- Mice
- Allosteric Regulation/drug effects
- Analgesics, Opioid/antagonists & inhibitors
- Analgesics, Opioid/pharmacology
- Binding Sites/drug effects
- Cryoelectron Microscopy
- Drug Evaluation, Preclinical
- Fentanyl/antagonists & inhibitors
- Fentanyl/pharmacology
- Kinetics
- Ligands
- Models, Molecular
- Morphine/antagonists & inhibitors
- Morphine/pharmacology
- Naloxone/administration & dosage
- Naloxone/chemistry
- Naloxone/metabolism
- Naloxone/pharmacology
- Narcotic Antagonists/administration & dosage
- Narcotic Antagonists/chemistry
- Narcotic Antagonists/metabolism
- Narcotic Antagonists/pharmacology
- Opiate Overdose/drug therapy
- Protein Conformation/drug effects
- Protein Stability/drug effects
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/chemistry
- Receptors, Opioid, mu/metabolism
- Sf9 Cells
- Signal Transduction/drug effects
- Small Molecule Libraries/chemistry
- Small Molecule Libraries/pharmacology
- Mice, Inbred C57BL
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Affiliation(s)
- Evan S O'Brien
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Vipin Ashok Rangari
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Amal El Daibani
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Shainnel O Eans
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA
| | - Haylee R Hammond
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA
| | - Elizabeth White
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Haoqing Wang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Yuki Shiimura
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
- Division of Molecular Genetics, Institute of Life Science, Kurume University, Fukuoka, Japan
| | - Kaavya Krishna Kumar
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Qianru Jiang
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Kevin Appourchaux
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Weijiao Huang
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA
| | - Chensong Zhang
- Division of CryoEM and Bioimaging, SSRL, SLAC National Acceleration Laboratory, Menlo Park, CA, USA
| | | | - Jesper M Mathiesen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Tao Che
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, USA
| | - Jay P McLaughlin
- Department of Pharmacodynamics, University of Florida, Gainesville, FL, USA.
| | - Susruta Majumdar
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy at St Louis and Washington University School of Medicine, St Louis, MO, USA.
| | - Brian K Kobilka
- Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, CA, USA.
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7
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Vu LY, Luo D, Johnson K, Denehy ED, Songrady JC, Martin J, Trivedi R, Alsum AR, Shaykin JD, Chaudhary CL, Woloshin EJ, Kornberger L, Bhuiyan N, Parkin S, Jiang Q, Che T, Alilain W, Turner JR, Bardo MT, Prisinzano TE. Searching for Synthetic Opioid Rescue Agents: Identification of a Potent Opioid Agonist with Reduced Respiratory Depression. J Med Chem 2024; 67:9173-9193. [PMID: 38810170 DOI: 10.1021/acs.jmedchem.4c00333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
While in the process of designing more effective synthetic opioid rescue agents, we serendipitously identified a new chemotype of potent synthetic opioid. Here, we report that conformational constraint of a piperazine ring converts a mu opioid receptor (MOR) antagonist into a potent MOR agonist. The prototype of the series, which we have termed atoxifent (2), possesses potent in vitro agonist activity. In mice, atoxifent displayed long-lasting antinociception that was reversible with naltrexone. Repeated dosing of atoxifent produced antinociceptive tolerance and a level of withdrawal like that of fentanyl. In rats, while atoxifent produced complete loss of locomotor activity like fentanyl, it failed to produce deep respiratory depression associated with fentanyl-induced lethality. Assessment of brain biodistribution demonstrated ample distribution of atoxifent into the brain with a Tmax of approximately 0.25 h. These results indicate enhanced safety for atoxifent-like molecules compared to fentanyl.
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Affiliation(s)
- Loan Y Vu
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Dan Luo
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Kai Johnson
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Emily D Denehy
- Department of Psychology, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Judy C Songrady
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Jocelyn Martin
- Department of Psychology, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Riya Trivedi
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Alexia R Alsum
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Jakob D Shaykin
- Department of Psychology, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Chhabi Lal Chaudhary
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Eric J Woloshin
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Lindsay Kornberger
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Nazmul Bhuiyan
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Sean Parkin
- Department of Chemistry, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Qianru Jiang
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy and Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Tao Che
- Center for Clinical Pharmacology, University of Health Sciences and Pharmacy and Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Warren Alilain
- Spinal Cord and Brain Injury Research Center (SCoBIRC), College of Medicine, University of Kentucky, Lexington, Kentucky 40536, United States
- Department of Neuroscience, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Jill R Turner
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
| | - Michael T Bardo
- Department of Psychology, University of Kentucky, Lexington, Kentucky 40536, United States
| | - Thomas E Prisinzano
- Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky 40506, United States
- Center for Pharmaceutical Research and Innovation, College of Pharmacy, University of Kentucky, Lexington, Kentucky 40506, United States
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8
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Alananzeh WA, Al-Qattan MN, Ayipo YO, Mordi MN. N-substituted tetrahydro-beta-carboline as mu-opioid receptors ligands: in silico study; molecular docking, ADMET and molecular dynamics approach. Mol Divers 2024; 28:1273-1289. [PMID: 37133710 DOI: 10.1007/s11030-023-10655-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/20/2023] [Indexed: 05/04/2023]
Abstract
Manipulating intracellular signals by interaction with transmembranal G-protein-coupled receptors (GPCRs) is the way of action of more than 30% of available medicines. Designing molecules against GPCRs is most challenging due to their flexible binding orthosteric and allosteric pockets, a property that lead to different mode and extent of activation of intracellular mediators. Here, in the current study we aimed to design N-substituted tetrahydro-beta-carbolines (THβC's) targeting Mu Opioid Receptors (MORs). We performed ligand docking study for reference and designed compounds against active and inactive states of MOR, as well as the active state bound to intracellular mediator of Gi. The reference compounds include 40 known agonists and antagonists, while the designed compounds include 25,227 N-substituted THβC analogues. Out of the designed compounds, 15 compounds were comparatively having better extra precision (XP) Gscore and were analyzed for absorption, distribution, metabolism, and excretion-toxicity (ADMET) properties, drug-likness, and molecular dynamic (MD) simulation. The results showed that N-substituted tetrahydro-beta-carbolines with and without C6-methoxy group substitutions (THBC/6MTHBC) analogues of A1/B1 and A9/B9 have relatively acceptable affinity and within pocket-stability toward MOR compared to the reference compounds of morphine (agonist) and naloxone (antagonist). Moreover, the designed analogues interact with key residue within the binding pocket of Asp 147 that is reported to be involved in receptor activation. In conclusion, the designed THBC analogues represent a good starting point for designing opioid receptor ligands other than morphinan scaffold, that have good synthetic accessibility which promotes feasible structural manipulation to tailor pharmacological effects with minimal side effects.
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Affiliation(s)
- Waleed A Alananzeh
- Center for Drug Research, Universiti Sains Malaysia, 11800, George Town, Pulau Penang, Malaysia.
| | - Mohammed N Al-Qattan
- College of Pharmacy, Knowledge University, Erbīl, Iraq
- College of Pharmacy, Nineveh University, Mosul, Iraq
| | - Yusuf Oloruntoyin Ayipo
- Center for Drug Research, Universiti Sains Malaysia, 11800, George Town, Pulau Penang, Malaysia
- Department of Chemistry and Industrial Chemistry, Kwara State University, Ilorin, Nigeria
| | - Mohd N Mordi
- Center for Drug Research, Universiti Sains Malaysia, 11800, George Town, Pulau Penang, Malaysia
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9
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Kaneko S, Imai S, Uchikubo-Kamo T, Hisano T, Asao N, Shirouzu M, Shimada I. Structural and dynamic insights into the activation of the μ-opioid receptor by an allosteric modulator. Nat Commun 2024; 15:3544. [PMID: 38740791 DOI: 10.1038/s41467-024-47792-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 04/12/2024] [Indexed: 05/16/2024] Open
Abstract
G-protein-coupled receptors (GPCRs) play pivotal roles in various physiological processes. These receptors are activated to different extents by diverse orthosteric ligands and allosteric modulators. However, the mechanisms underlying these variations in signaling activity by allosteric modulators remain largely elusive. Here, we determine the three-dimensional structure of the μ-opioid receptor (MOR), a class A GPCR, in complex with the Gi protein and an allosteric modulator, BMS-986122, using cryogenic electron microscopy. Our results reveal that BMS-986122 binding induces changes in the map densities corresponding to R1673.50 and Y2545.58, key residues in the structural motifs conserved among class A GPCRs. Nuclear magnetic resonance analyses of MOR in the absence of the Gi protein reveal that BMS-986122 binding enhances the formation of the interaction between R1673.50 and Y2545.58, thus stabilizing the fully-activated conformation, where the intracellular half of TM6 is outward-shifted to allow for interaction with the Gi protein. These findings illuminate that allosteric modulators like BMS-986122 can potentiate receptor activation through alterations in the conformational dynamics in the core region of GPCRs. Together, our results demonstrate the regulatory mechanisms of GPCRs, providing insights into the rational development of therapeutics targeting GPCRs.
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MESH Headings
- Receptors, Opioid, mu/metabolism
- Receptors, Opioid, mu/chemistry
- Receptors, Opioid, mu/genetics
- Allosteric Regulation
- Humans
- Cryoelectron Microscopy
- Protein Binding
- GTP-Binding Protein alpha Subunits, Gi-Go/metabolism
- GTP-Binding Protein alpha Subunits, Gi-Go/chemistry
- GTP-Binding Protein alpha Subunits, Gi-Go/genetics
- HEK293 Cells
- Ligands
- Models, Molecular
- Protein Conformation
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Affiliation(s)
- Shun Kaneko
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Shunsuke Imai
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan.
| | | | - Tamao Hisano
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
| | - Nobuaki Asao
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Mikako Shirouzu
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan
| | - Ichio Shimada
- Center for Biosystems Dynamics Research (BDR), RIKEN, Kanagawa, Japan.
- Graduate School of Integrated Science for Life, Hiroshima University, Hiroshima, Japan.
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10
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Eliasof A, Liu-Chen LY, Li Y. Peptide-derived ligands for the discovery of safer opioid analgesics. Drug Discov Today 2024; 29:103950. [PMID: 38514040 PMCID: PMC11127667 DOI: 10.1016/j.drudis.2024.103950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 03/03/2024] [Accepted: 03/13/2024] [Indexed: 03/23/2024]
Abstract
Drugs targeting the μ-opioid receptor (MOR) remain the most efficacious analgesics for the treatment of pain, but activation of MOR with current opioid analgesics also produces harmful side effects, notably physical dependence, addiction, and respiratory depression. Opioid peptides have been accepted as promising candidates for the development of safer and more efficacious analgesics. To develop peptide-based opioid analgesics, strategies such as modification of endogenous opioid peptides, development of multifunctional opioid peptides, G protein-biased opioid peptides, and peripherally restricted opioid peptides have been reported. This review seeks to provide an overview of the opioid peptides that produce potent antinociception with much reduced side effects in animal models and highlight the potential advantages of peptides as safer opioid analgesics.
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Affiliation(s)
- Abbe Eliasof
- College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
| | - Lee-Yuan Liu-Chen
- Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Yangmei Li
- College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA.
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11
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Provasi D, Filizola M. Enhancing Opioid Bioactivity Predictions through Integration of Ligand-Based and Structure-Based Drug Discovery Strategies with Transfer and Deep Learning Techniques. J Phys Chem B 2023; 127:10691-10699. [PMID: 38084046 PMCID: PMC11252170 DOI: 10.1021/acs.jpcb.3c05306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
The opioid epidemic has cast a shadow over public health, necessitating immediate action to address its devastating consequences. To effectively combat this crisis, it is crucial to discover better opioid drugs with reduced addiction potential. Artificial intelligence-based and other machine learning tools, particularly deep learning models, have garnered significant attention in recent years for their potential to advance drug discovery. However, using these tools poses challenges, especially when training samples are insufficient to achieve adequate prediction performance. In this study, we investigate the effectiveness of transfer learning in building robust deep learning models to enhance ligand bioactivity prediction for each individual opioid receptor (OR) subtype. This is achieved by leveraging knowledge obtained from pretraining a model using supervised learning on a larger data set of bioactivity data combined with ligand-based and structure-based molecular descriptors related to the entire OR subfamily. Our studies hold the potential to advance opioid research by enabling the rapid identification of novel chemical probes with specific bioactivities, which can aid in the study of receptor function and contribute to the future development of improved opioid therapeutics.
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Affiliation(s)
- Davide Provasi
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, New York 10029, United States
| | - Marta Filizola
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, New York 10029, United States
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12
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Yu J, Kumar A, Zhang X, Martin C, Raia P, Koehl A, Laeremans T, Steyaert J, Manglik A, Ballet S, Boland A, Stoeber M. Structural Basis of μ-Opioid Receptor-Targeting by a Nanobody Antagonist. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.06.570395. [PMID: 38106026 PMCID: PMC10723425 DOI: 10.1101/2023.12.06.570395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
The μ-opioid receptor (μOR), a prototypical member of the G protein-coupled receptor (GPCR) family, is the molecular target of opioid analgesics such as morphine and fentanyl. Due to the limitations and severe side effects of currently available opioid drugs, there is considerable interest in developing novel modulators of μOR function. Most GPCR ligands today are small molecules, however biologics, including antibodies and nanobodies, are emerging as alternative therapeutics with clear advantages such as affinity and target selectivity. Here, we describe the nanobody NbE, which selectively binds to the μOR and acts as an antagonist. We functionally characterize NbE as an extracellular and genetically encoded μOR ligand and uncover the molecular basis for μOR antagonism by solving the cryo-EM structure of the NbE-μOR complex. NbE displays a unique ligand binding mode and achieves μOR selectivity by interactions with the orthosteric pocket and extracellular receptor loops. Based on a β-hairpin loop formed by NbE that deeply inserts into the μOR and centers most binding contacts, we design short peptide analogues that retain μOR antagonism. The work illustrates the potential of nanobodies to uniquely engage with GPCRs and describes novel μOR ligands that can serve as a basis for therapeutic developments.
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Affiliation(s)
- Jun Yu
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Amit Kumar
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
| | - Xuefeng Zhang
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Charlotte Martin
- Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Pierre Raia
- Department of Plant Sciences, University of Geneva, Geneva, Switzerland
| | - Antoine Koehl
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA, USA
| | | | - Jan Steyaert
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
- VIB-VUB Center for Structural Biology, VIB, Brussels, Belgium
| | - Aashish Manglik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Steven Ballet
- Departments of Chemistry and Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Andreas Boland
- Department of Molecular and Cellular Biology, University of Geneva, Geneva, Switzerland
| | - Miriam Stoeber
- Department of Cell Physiology and Metabolism, University of Geneva, Geneva, Switzerland
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13
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Saller J, List C, Hübner H, Gmeiner P, Clark T, Pischetsrieder M. Identification and quantification of kukoamine A and kukoamine B as novel μ-opioid receptor agonists in potato and other solanaceous plants. Food Chem 2023; 427:136637. [PMID: 37385059 DOI: 10.1016/j.foodchem.2023.136637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 06/02/2023] [Accepted: 06/13/2023] [Indexed: 07/01/2023]
Abstract
Activation of the µ-opioid receptor (µOR) by food components could lead to reward effects or to the modulation of motor functions in the gastrointestinal tract. In an unbiased search for novel µOR agonists in food, a three-step virtual-screening process selected 22 promising candidates with potential to interact with the µOR. Radioligand binding studies showed that ten of these substances indeed bind to the receptor. Functional assays identified kukoamine A as a full agonist (EC50 = 5.6 µM) and kukoamine B as a partial agonist (EC50 = 8.7 µM) to µOR. After extraction, both kukoamines were analyzed by LC-MS/MS in potato, tomato, pepper, and eggplant. Depending on the potato variety, up to 16 µg of kukoamine A and 157 µg of kukoamine B per gram dry weight could be determined in the whole tuber, mainly concentrated in the potato peel. Cooking did not influence the kukoamine contents.
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Affiliation(s)
- Julia Saller
- Food Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany.
| | - Carina List
- Food Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany.
| | - Harald Hübner
- Medicinal Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany.
| | - Peter Gmeiner
- Medicinal Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany; FAU NeW - Research Center New Bioactive Compounds, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany.
| | - Timothy Clark
- Computer Chemistry Center, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nägelsbachstraße 25, 91052 Erlangen, Germany.
| | - Monika Pischetsrieder
- Food Chemistry, Department of Chemistry and Pharmacy, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany; FAU NeW - Research Center New Bioactive Compounds, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nikolaus-Fiebiger-Str. 10, 91058 Erlangen, Germany.
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14
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Ramos-Gonzalez N, Paul B, Majumdar S. IUPHAR themed review: Opioid efficacy, bias, and selectivity. Pharmacol Res 2023; 197:106961. [PMID: 37844653 DOI: 10.1016/j.phrs.2023.106961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/10/2023] [Accepted: 10/11/2023] [Indexed: 10/18/2023]
Abstract
Drugs acting at the opioid receptor family are clinically used to treat chronic and acute pain, though they represent the second line of treatment behind GABA analogs, antidepressants and SSRI's. Within the opioid family mu and kappa opioid receptor are commonly targeted. However, activation of the mu opioid receptor has side effects of constipation, tolerance, dependence, euphoria, and respiratory depression; activation of the kappa opioid receptor leads to dysphoria and sedation. The side effects of mu opioid receptor activation have led to mu receptor drugs being widely abused with great overdose risk. For these reasons, newer safer opioid analgesics are in high demand. For many years a focus within the opioid field was finding drugs that activated the G protein pathway at mu opioid receptor, without activating the β-arrestin pathway, known as biased agonism. Recent advances have shown that this may not be the way forward to develop safer analgesics at mu opioid receptor, though there is still some promise at the kappa opioid receptor. Here we discuss recent novel approaches to develop safer opioid drugs including efficacy vs bias and fine-tuning receptor activation by targeting sub-pockets in the orthosteric site, we explore recent works on the structural basis of bias, and we put forward the suggestion that Gα subtype selectivity may be an exciting new area of interest.
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Affiliation(s)
- Nokomis Ramos-Gonzalez
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, Saint Louis, MO, USA; Center for Clinical Pharmacology, University of Health Sciences & Pharmacy at St. Louis and Washington University School of Medicine, St. Louis, MO, USA
| | - Barnali Paul
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, Saint Louis, MO, USA; Center for Clinical Pharmacology, University of Health Sciences & Pharmacy at St. Louis and Washington University School of Medicine, St. Louis, MO, USA
| | - Susruta Majumdar
- Department of Anesthesiology and Washington University Pain Center, Washington University School of Medicine, Saint Louis, MO, USA; Center for Clinical Pharmacology, University of Health Sciences & Pharmacy at St. Louis and Washington University School of Medicine, St. Louis, MO, USA.
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15
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Fairbanks CA, Peterson CD. The opioid receptor: emergence through millennia of pharmaceutical sciences. FRONTIERS IN PAIN RESEARCH 2023; 4:960389. [PMID: 38028425 PMCID: PMC10646403 DOI: 10.3389/fpain.2023.960389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 10/02/2023] [Indexed: 12/01/2023] Open
Abstract
Throughout history humanity has searched for an optimal approach to the use of opioids that maximizes analgesia while minimizing side effects. This review reflects upon the conceptualization of the opioid receptor and the critical role that the pharmaceutical sciences played in its revelation. Opium-containing formulations have been delivered by various routes of administration for analgesia and other therapeutic indications for millennia. The concept of a distinct site of opium action evolved as practitioners developed innovative delivery methods, such as intravenous administration, to improve therapeutic outcomes. The introduction of morphine and synthetic opioids engendered the prevalent assumption of a common opioid receptor. Through consideration of structure-activity relationships, spatial geometry, and pharmacological differences of known ligands, the idea of multiple opioid receptors emerged. By accessing the high-affinity property of naloxone, the opioid receptor was identified in central and peripheral nervous system tissue. The endogenous opioid neuropeptides were subsequently discovered. Application of mu-, delta-, and kappa- opioid receptor-selective ligands facilitated the pharmacological characterization and distinctions between the three receptors, which were later cloned and sequenced. Opioid receptor signal transduction pathways were described and attributed to specific physiological outcomes. The crystal structures of mu, delta, kappa, and nociceptin/orphanin FQ receptors bound to receptor-selective ligands have been elucidated. Comparison of these structures reveal locations of ligand binding and engagement of signal transduction pathways. Expanding knowledge regarding the structure and actions of the opioid receptor fuels contemporary strategies for driving the activity of opioid receptors toward maximizing therapeutic and minimizing adverse outcomes.
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Affiliation(s)
- Carolyn A. Fairbanks
- Department of Pharmaceutics, University of Minnesota, Minneapolis, MN, United States
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, United States
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
| | - Cristina D. Peterson
- Department of Pharmaceutics, University of Minnesota, Minneapolis, MN, United States
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, United States
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16
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Munro TA. Reanalysis of a μ opioid receptor crystal structure reveals a covalent adduct with BU72. BMC Biol 2023; 21:213. [PMID: 37817141 PMCID: PMC10566028 DOI: 10.1186/s12915-023-01689-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 08/25/2023] [Indexed: 10/12/2023] Open
Abstract
BACKGROUND The first crystal structure of the active μ opioid receptor (μOR) exhibited several unexplained features. The ligand BU72 exhibited many extreme deviations from ideal geometry, along with unexplained electron density. I previously showed that inverting the benzylic configuration resolved these problems, establishing revised stereochemistry of BU72 and its analog BU74. However, another problem remains unresolved: additional unexplained electron density contacts both BU72 and a histidine residue in the N-terminus, revealing the presence of an as-yet unidentified atom. RESULTS These short contacts and uninterrupted density are inconsistent with non-covalent interactions. Therefore, BU72 and μOR form a covalent adduct, rather than representing two separate entities as in the original model. A subsequently proposed magnesium complex is inconsistent with multiple lines of evidence. However, oxygen fits the unexplained density well. While the structure I propose is tentative, similar adducts have been reported previously in the presence of reactive oxygen species. Moreover, known sources of reactive oxygen species were present: HEPES buffer, nickel ions, and a sequence motif that forms redox-active nickel complexes. This motif contacts the unexplained density. The adduct exhibits severe strain, and the tethered N-terminus forms contacts with adjacent residues. These forces, along with the nanobody used as a G protein substitute, would be expected to influence the receptor conformation. Consistent with this, the intracellular end of the structure differs markedly from subsequent structures of active μOR bound to Gi protein. CONCLUSIONS Later Gi-bound structures are likely to be more accurate templates for ligand docking and modelling of active G protein-bound μOR. The possibility of reactions like this should be considered in the choice of protein truncation sites and purification conditions, and in the interpretation of excess or unexplained density.
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Affiliation(s)
- Thomas A Munro
- School of Life and Environmental Sciences, Deakin University, Burwood, VIC, 3125, Australia.
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17
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de Lima MRP, Bezerra RFS, Serafim DDB, Sena Junior DM. Dynamics of the Apo µ-Opioid Receptor in Complex with Gi Protein. Int J Mol Sci 2023; 24:13430. [PMID: 37686252 PMCID: PMC10487971 DOI: 10.3390/ijms241713430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Revised: 08/24/2023] [Accepted: 08/25/2023] [Indexed: 09/10/2023] Open
Abstract
Opioid receptors, particularly the µ-opioid receptor (μOR), play a pivotal role in mediating the analgesic and addictive effects of opioid drugs. G protein signaling is an important pathway of μOR function, usually associated with painkilling effects. However, the molecular mechanisms underlying the interaction between the μOR and G protein remain poorly understood. In this study, we employed classical all-atom molecular dynamics simulations to investigate the structural changes occurring with the μOR-G protein complex under two different conditions: with the G protein in the apo form (open) and with the GDP bound G protein (closed, holo form). The receptor was in the apo form and active conformation in both cases, and the simulation time comprised 1µs for each system. In order to assess the effect of the G protein coupling on the receptor activation state, three parameters were monitored: the correlation of the distance between TM3 and TM6 and the RMSD of the NPxxYA motif; the universal activation index (A100); and the χ2 dihedral distribution of residue W2936.48. When complexed with the open G protein, receptor conformations with intermediate activation state prevailed throughout the molecular dynamics, whereas in the condition with the closed G protein, mostly inactive conformations of the receptor were observed. The major effect of the G protein in the receptor conformation comes from a steric hindrance involving an intracellular loop of the receptor and a β-sheet region of the G protein. This suggests that G-protein precoupling is essential for receptor activation, but this fact is not sufficient for complete receptor activation.
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Affiliation(s)
- Mira Raya Paula de Lima
- Biological Chemistry Department, Universidade Regional do Cariri—URCA, Crato 63105-000, CE, Brazil; (R.F.S.B.); (D.D.B.S.)
- Instituto Federal de Educação Ciência e Tecnologia do Ceará—IFCE, Juazeiro do Norte 63040-540, CE, Brazil
| | - Rubem Francisco Silva Bezerra
- Biological Chemistry Department, Universidade Regional do Cariri—URCA, Crato 63105-000, CE, Brazil; (R.F.S.B.); (D.D.B.S.)
| | - David Denis Bento Serafim
- Biological Chemistry Department, Universidade Regional do Cariri—URCA, Crato 63105-000, CE, Brazil; (R.F.S.B.); (D.D.B.S.)
| | - Diniz Maciel Sena Junior
- Biological Chemistry Department, Universidade Regional do Cariri—URCA, Crato 63105-000, CE, Brazil; (R.F.S.B.); (D.D.B.S.)
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18
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Provasi D, Filizola M. Enhancing Opioid Bioactivity Predictions through Integration of Ligand-Based and Structure-Based Drug Discovery Strategies with Transfer and Deep Learning Techniques. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.04.552065. [PMID: 37609329 PMCID: PMC10441297 DOI: 10.1101/2023.08.04.552065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
The opioid epidemic has cast a shadow over public health, necessitating immediate action to address its devastating consequences. To effectively combat this crisis, it is crucial to discover better opioid drugs with reduced addiction potential. Artificial intelligence-based and other machine learning tools, particularly deep learning models, have garnered significant attention in recent years for their potential to advance drug discovery. However, utilizing these tools poses challenges, especially when training samples are insufficient to achieve adequate prediction performance. In this study, we investigate the effectiveness of transfer learning using combined ligand-based and structure-based molecular descriptors from the entire opioid receptor (OR) subfamily in building robust deep learning models for enhanced bioactivity prediction of opioid ligands at each individual OR subtype. Our studies hold the potential to greatly advance opioid research by enabling the rapid identification of novel chemical probes with specific bioactivities, which can aid in the study of receptor function and contribute to the future development of improved opioid therapeutics.
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19
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Cai B, El Daibani A, Bai Y, Che T, Krusemark CJ. Direct Selection of DNA-Encoded Libraries for Biased Agonists of GPCRs on Live Cells. JACS AU 2023; 3:1076-1088. [PMID: 37124302 PMCID: PMC10131204 DOI: 10.1021/jacsau.2c00674] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 05/03/2023]
Abstract
G protein-coupled receptors (GPCRs) are the largest superfamily of human membrane target proteins for approved drugs. GPCR ligands can have a complex array of pharmacological activities. Among these activities, biased agonists have potential to serve as both chemical probes to understand specific aspects of receptor signaling and therapeutic leads with more specific, desired activity. Challenges exist, however, in the development of new biased activators due, in part, to the low throughput of traditional screening approaches. DNA-encoded chemical libraries (DELs) dramatically improve the throughput of drug discovery by allowing a collective selection, rather than discrete screening, of large compound libraries. The use of DELs has been largely limited to affinity-based selections against purified protein targets, which identify binders only. Herein, we report a split protein complementation approach that allows direct identification of DNA-linked molecules that induce the dimerization of two proteins. We used this selection with a DEL against opioid receptor GPCRs on living cells for the identification of small molecules that possess the specific function of activation of either β-arrestin or G protein signaling pathways. This approach was applied to δ-, μ-, and κ-opioid receptors and enabled the discovery of compound [66,66], a selective, G-protein-biased agonist of the κ-opioid receptor (EC50 = 100 nM, E max = 82%, Gi bias factor = 6.6). This approach should be generally applicable for the direct selection of chemical inducers of dimerization from DELs and expand the utility of DELs to enrich molecules with a specific and desired biochemical function.
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Affiliation(s)
- Bo Cai
- Department
of Medicinal Chemistry and Molecular Pharmacology, Purdue Center for
Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Amal El Daibani
- Center
for Clinical Pharmacology, Department of Anesthesiology, Washington University in St. Louis, St. Louis, Missouri 63110, United States
| | - Yuntian Bai
- Department
of Medicinal Chemistry and Molecular Pharmacology, Purdue Center for
Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
| | - Tao Che
- Center
for Clinical Pharmacology, Department of Anesthesiology, Washington University in St. Louis, St. Louis, Missouri 63110, United States
| | - Casey J. Krusemark
- Department
of Medicinal Chemistry and Molecular Pharmacology, Purdue Center for
Cancer Research, Purdue University, West Lafayette, Indiana 47907, United States
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20
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Dmitrieva DA, Kotova TV, Safronova NA, Sadova AA, Dashevskii DE, Mishin AV. Protein Design Strategies for the Structural–Functional Studies of G Protein-Coupled Receptors. BIOCHEMISTRY (MOSCOW) 2023; 88:S192-S226. [PMID: 37069121 DOI: 10.1134/s0006297923140110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
G protein-coupled receptors (GPCRs) are an important family of membrane proteins responsible for many physiological functions in human body. High resolution GPCR structures are required to understand their molecular mechanisms and perform rational drug design, as GPCRs play a crucial role in a variety of diseases. That is difficult to obtain for the wild-type proteins because of their low stability. In this review, we discuss how this problem can be solved by using protein design strategies developed to obtain homogeneous stabilized GPCR samples for crystallization and cryoelectron microscopy.
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Affiliation(s)
- Daria A Dmitrieva
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Tatiana V Kotova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Nadezda A Safronova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Alexandra A Sadova
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Dmitrii E Dashevskii
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia
| | - Alexey V Mishin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region, 141701, Russia.
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21
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Meqbil YJ, van Rijn RM. Opportunities and Challenges for In Silico Drug Discovery at Delta Opioid Receptors. Pharmaceuticals (Basel) 2022; 15:873. [PMID: 35890173 PMCID: PMC9324648 DOI: 10.3390/ph15070873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/13/2022] [Indexed: 11/29/2022] Open
Abstract
The delta opioid receptor is a Gi-protein-coupled receptor (GPCR) with a broad expression pattern both in the central nervous system and the body. The receptor has been investigated as a potential target for a multitude of significant diseases including migraine, alcohol use disorder, ischemia, and neurodegenerative diseases. Despite multiple attempts, delta opioid receptor-selective molecules have not been translated into the clinic. Yet, the therapeutic promise of the delta opioid receptor remains and thus there is a need to identify novel delta opioid receptor ligands to be optimized and selected for clinical trials. Here, we highlight recent developments involving the delta opioid receptor, the closely related mu and kappa opioid receptors, and in the broader area of the GPCR drug discovery research. We focus on the validity and utility of the available delta opioid receptor structures. We also discuss the increased ability to perform ultra-large-scale docking studies on GPCRs, the rise in high-resolution cryo-EM structures, and the increased prevalence of machine learning and artificial intelligence in drug discovery. Overall, we pose that there are multiple opportunities to enable in silico drug discovery at the delta opioid receptor to identify novel delta opioid modulators potentially with unique pharmacological properties, such as biased signaling.
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Affiliation(s)
- Yazan J. Meqbil
- Department of Medicinal Chemistry and Molecular Pharmacology, Computational Interdisciplinary Graduate Program, Purdue University, West Lafayette, IN 47907, USA;
| | - Richard M. van Rijn
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue Institute for Drug Discovery, Purdue Institute for Neuroscience, Purdue University, West Lafayette, IN 47907, USA
- Septerna Inc., South San Francisco, CA 94080, USA
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22
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Oken AC, Krishnamurthy I, Savage JC, Lisi NE, Godsey MH, Mansoor SE. Molecular Pharmacology of P2X Receptors: Exploring Druggable Domains Revealed by Structural Biology. Front Pharmacol 2022; 13:925880. [PMID: 35784697 PMCID: PMC9248971 DOI: 10.3389/fphar.2022.925880] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/10/2022] [Indexed: 11/18/2022] Open
Abstract
Extracellular ATP is a critical signaling molecule that is found in a wide range of concentrations across cellular environments. The family of nonselective cation channels that sense extracellular ATP, termed P2X receptors (P2XRs), is composed of seven subtypes (P2X1-P2X7) that assemble as functional homotrimeric and heterotrimeric ion channels. Each P2XR is activated by a distinct concentration of extracellular ATP, spanning from high nanomolar to low millimolar. P2XRs are implicated in a variety of physiological and pathophysiological processes in the cardiovascular, immune, and central nervous systems, corresponding to the spatiotemporal expression, regulation, and activation of each subtype. The therapeutic potential of P2XRs is an emerging area of research in which structural biology has seemingly exceeded medicinal chemistry, as there are several published P2XR structures but currently no FDA-approved drugs targeting these ion channels. Cryogenic electron microscopy is ideally suited to facilitate structure-based drug design for P2XRs by revealing and characterizing novel ligand-binding sites. This review covers structural elements in P2XRs including the extracellular orthosteric ATP-binding site, extracellular allosteric modulator sites, channel pore, and cytoplasmic substructures, with an emphasis on potential therapeutic ligand development.
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Affiliation(s)
- Adam C. Oken
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
| | - Ipsita Krishnamurthy
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
| | - Jonathan C. Savage
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
| | - Nicolas E. Lisi
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
| | - Michael H. Godsey
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
| | - Steven E. Mansoor
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, OR, United States
- *Correspondence: Steven E. Mansoor,
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