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Lee YS. Peptidomimetics and Their Applications for Opioid Peptide Drug Discovery. Biomolecules 2022; 12:biom12091241. [PMID: 36139079 PMCID: PMC9496382 DOI: 10.3390/biom12091241] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 08/29/2022] [Accepted: 09/02/2022] [Indexed: 11/16/2022] Open
Abstract
Despite various advantages, opioid peptides have been limited in their therapeutic uses due to the main drawbacks in metabolic stability, blood-brain barrier permeability, and bioavailability. Therefore, extensive studies have focused on overcoming the problems and optimizing the therapeutic potential. Currently, numerous peptide-based drugs are being marketed thanks to new synthetic strategies for optimizing metabolism and alternative routes of administration. This tutorial review briefly introduces the history and role of natural opioid peptides and highlights the key findings on their structure-activity relationships for the opioid receptors. It discusses details on opioid peptidomimetics applied to develop therapeutic candidates for the treatment of pain from the pharmacological and structural points of view. The main focus is the current status of various mimetic tools and the successful applications summarized in tables and figures.
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Affiliation(s)
- Yeon Sun Lee
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, AZ 85724, USA
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2
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Bis-Cyclic Guanidine Heterocyclic Peptidomimetics as Opioid Ligands with Mixed μ-, κ- and δ-Opioid Receptor Interactions: A Potential Approach to Novel Analgesics. Int J Mol Sci 2022; 23:ijms23179623. [PMID: 36077029 PMCID: PMC9455983 DOI: 10.3390/ijms23179623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 08/19/2022] [Accepted: 08/20/2022] [Indexed: 11/25/2022] Open
Abstract
The design and development of analgesics with mixed-opioid receptor interactions has been reported to decrease side effects, minimizing respiratory depression and reinforcing properties to generate safer analgesic therapeutics. We synthesized bis-cyclic guanidine heterocyclic peptidomimetics from reduced tripeptides. In vitro screening with radioligand competition binding assays demonstrated variable affinity for the mu-opioid receptor (MOR), delta-opioid receptor (DOR), and kappa-opioid receptor (KOR) across the series, with compound 1968-22 displaying good affinity for all three receptors. Central intracerebroventricular (i.c.v.) administration of 1968-22 produced dose-dependent, opioid receptor-mediated antinociception in the mouse 55 °C warm-water tail-withdrawal assay, and 1968-22 also produced significant antinociception up to 80 min after oral administration (10 mg/kg, p.o.). Compound 1968-22 was detected in the brain 5 min after intravenous administration and was shown to be stable in the blood for at least 30 min. Central administration of 1968-22 did not produce significant respiratory depression, locomotor effects or conditioned place preference or aversion. The data suggest these bis-cyclic guanidine heterocyclic peptidomimetics with multifunctional opioid receptor activity may hold potential as new analgesics with fewer liabilities of use.
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3
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Spetea M, Schmidhammer H. Kappa Opioid Receptor Ligands and Pharmacology: Diphenethylamines, a Class of Structurally Distinct, Selective Kappa Opioid Ligands. Handb Exp Pharmacol 2021; 271:163-195. [PMID: 33454858 DOI: 10.1007/164_2020_431] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The kappa opioid receptor (KOR), a G protein-coupled receptor, and its endogenous ligands, the dynorphins, are prominent members of the opioid neuromodulatory system. The endogenous kappa opioid system is expressed in the central and peripheral nervous systems, and has a key role in modulating pain in central and peripheral neuronal circuits and a wide array of physiological functions and neuropsychiatric behaviors (e.g., stress, reward, emotion, motivation, cognition, epileptic seizures, itch, and diuresis). We review the latest advances in pharmacology of the KOR, chemical developments on KOR ligands with advances and challenges, and therapeutic and potential applications of KOR ligands. Diverse discovery strategies of KOR ligands targeting natural, naturally derived, and synthetic compounds with different scaffolds, as small molecules or peptides, with short or long-acting pharmacokinetics, and central or peripheral site of action, are discussed. These research efforts led to ligands with distinct pharmacological properties, as agonists, partial agonists, biased agonists, and antagonists. Differential modulation of KOR signaling represents a promising strategy for developing pharmacotherapies for several human diseases, either by activating (treatment of pain, pruritus, and epilepsy) or blocking (treatment of depression, anxiety, and addiction) the receptor. We focus on the recent chemical and pharmacological advances on diphenethylamines, a new class of structurally distinct, selective KOR ligands. Design strategies and investigations to define structure-activity relationships together with in vivo pharmacology of diphenethylamines as agonists, biased agonists, and antagonists and their potential use as therapeutics are discussed.
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Affiliation(s)
- Mariana Spetea
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria.
| | - Helmut Schmidhammer
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innsbruck, Austria
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4
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Wu Z, Hruby VJ. Toward a Universal μ-Agonist Template for Template-Based Alignment Modeling of Opioid Ligands. ACS OMEGA 2019; 4:17457-17476. [PMID: 31656918 PMCID: PMC6812133 DOI: 10.1021/acsomega.9b02244] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 09/25/2019] [Indexed: 05/04/2023]
Abstract
Opioid ligands are a large group of G-protein-coupled receptor ligands possessing high structural diversity, along with complicated structure-activity relationships (SARs). To better understand their structural correlations as well as the related SARs, we developed the innovative template-based alignment modeling in our recent studies on a variety of opioid ligands. As previously reported, this approach showed promise but also with limitations, which was mainly attributed to the small size of morphine as a template. With this study, we set out to construct an artificial μ-agonist template to overcome this limitation. The newly constructed template contained a largely extended scaffold, along with a few special μ-features relevant to the μ-selectivity of opioid ligands. As demonstrated in this paper, the new template showed significantly improved efficacy in facilitating the alignment modeling of a wide variety of opioid ligands. This report comprises of two main parts. Part 1 discusses the general construction process and the structural features as well as a few typical examples of the template applications and Part 2 focuses on the template refinement and validation.
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Affiliation(s)
- Zhijun Wu
- ABC Resource, Plainsboro, New Jersey 08536, United States
- E-mail:
| | - Victor J. Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85716, United States
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Fang WJ, Murray TF, Aldrich JV. Design, synthesis, and opioid activity of arodyn analogs cyclized by ring-closing metathesis involving Tyr(allyl). Bioorg Med Chem 2017; 26:1157-1161. [PMID: 29273415 DOI: 10.1016/j.bmc.2017.11.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 01/31/2023]
Abstract
Kappa (κ) opioid receptor selective antagonists are useful pharmacological tools in studying κ opioid receptors and have potential to be used as therapeutic agents for the treatment of a variety of diseases including mood disorders and drug addiction. Arodyn (Ac[Phe1-3,Arg4,d-Ala8]Dyn A-(1-11)NH2) is a linear acetylated dynorphin A (Dyn A) analog that is a potent and selective κ opioid receptor antagonist (Bennett et al. J Med Chem 2002;45:5617-5619) and prevents stress-induced reinstatement of cocaine-seeking behavior following central administration (Carey et al. Eur J Pharmacol 2007;569:84-89). To restrict its conformational mobility, explore possible bioactive conformations and potentially increase its metabolic stability we synthesized cyclic arodyn analogs on solid phase utilizing a novel ring-closing metathesis (RCM) reaction involving allyl-protected Tyr (Tyr(All)) residues. This approach preserves the aromatic functionality and directly constrains the side chains of one or more of the Phe residues. The novel cyclic arodyn analog 4 cyclized between Tyr(All) residues incorporated in positions 2 and 3 exhibited potent κ opioid receptor antagonism in the [35S]GTPγS assay (KB = 3.2 nM) similar to arodyn. Analog 3 cyclized between Tyr(All) residues in positions 1 and 2 also exhibited nanomolar κ opioid receptor antagonist potency (KB = 27.5 nM) in this assay. These are the first opioid peptides cyclized via RCM involving aromatic residues, and given their promising pharmacological activity represent novel lead peptides for further exploration.
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Affiliation(s)
- Wei-Jie Fang
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045, USA
| | - Thomas F Murray
- Department of Pharmacology, Creighton University, Omaha, NE 68178, USA
| | - Jane V Aldrich
- Department of Medicinal Chemistry, University of Kansas, Lawrence, KS 66045, USA; Department of Medicinal Chemistry, University of Florida, Gainesville, FL 32610, USA.
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6
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Deming TJ. Functional Modification of Thioether Groups in Peptides, Polypeptides, and Proteins. Bioconjug Chem 2017; 28:691-700. [DOI: 10.1021/acs.bioconjchem.6b00696] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Timothy J. Deming
- 5121 Engineering
5, Department of Bioengineering and Department of Chemistry and Biochemistry, University of California, Los
Angeles, California 90095, United States
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7
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Abstract
Acute pain management is improving steadily over the past few years, but training and professional education are still lacking in many professions. Untreated or undertreated acute pain could have detrimental effects on the patient in terms of comfort and recovery from trauma or surgery. Acute undertreated pain can decrease a patient's vascular perfusion, increase oxygen demand, suppress the immune system, and possibly risk increased incidence of venous thrombosis. Although acute postoperative pain needs to be managed aggressively, patients are most vulnerable during this period for developing adverse effects, and therefore, patient assessment and careful drug therapy evaluation are necessary processes in therapeutic planning. Acute pain management requires careful and thorough initial assessment and follow-up reassessment in addition to frequent dosage adjustments, and managing analgesic induced side effects. Analgesic selection and dosing must be based on the patient's past and recent analgesic exposure. There is no single acute pain management regimen that is suitable for all patients. Analgesics must be tailored to the individual patient.
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Affiliation(s)
- Peter J. S. Koo
- Departments of Clinical Pharmacy and Pharmaceutical Services, University of California, San Francisco, San Francisco, California
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8
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Medicinal significance of naturally occurring cyclotetrapeptides. J Nat Med 2016; 70:708-20. [PMID: 27300506 DOI: 10.1007/s11418-016-1001-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 04/18/2016] [Indexed: 12/20/2022]
Abstract
Bioactive natural products are serendipitous drug candidates, which stimulate synthetic approaches for improving and supporting drug discovery and development. Therefore, the search for bioactive metabolites from different natural sources continues to play an important role in fashioning new medicinal agents. Several cyclic peptides were produced by organisms, such as β-defensins, gramicidin S, and tyrocidine A, and exhibited a wide range of bioactivities, such as antiviral activity against HIV-1, influenza A viruses, or antibacterial activity. Cyclic tetrapeptides are a class of natural products that were found to have a broad range of biological activities, promising pharmacokinetic properties, as well as interesting conformational dynamics and ability of slow inter-conversion to several different structures. Cyclooligopeptides, particularly medium ring-sized peptides, were obtained from marine microorganisms and exhibited a wide range of pharmacological properties, including antimicrobial and anti-dinoflagellate activities, cytotoxicity, and inhibitory activity against enzyme sortase B. Most of the naturally occurring cyclotetrapeptides are obtained from fungi. Some natural cyclic tetrapeptides were found to inhibit histone deacetylase (HDAC), which regulate the expression of genes. These compounds are very useful as cancer therapeutics. Various analogues of the natural cyclotetrapeptides were successfully synthesized to find novel lead compounds for pharmacological and biotechnological applications. Therefore, in this review, previously reported novel natural cyclotetrapeptides are briefly discussed, along with their important biological activities as drug candidates, together with their promising therapeutic properties. Moreover, their future perspective in drug discovery as potential therapeutic agents will be determined.
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9
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Gharakhanian EG, Deming TJ. Chemoselective synthesis of functional homocysteine residues in polypeptides and peptides. Chem Commun (Camb) 2016; 52:5336-9. [DOI: 10.1039/c6cc01253a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A procedure for conversion of methionine residue into functional homocysteine residue has been described.
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Affiliation(s)
| | - Timothy J. Deming
- Department of Chemistry and Biochemistry
- University of California
- Los Angeles
- USA
- Department of Bioengineering
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10
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Rational Approach to the Design of Bioactive Peptidomimetics: Recent Developments in Opioid Agonist Peptides. STUDIES IN NATURAL PRODUCTS CHEMISTRY 2015. [DOI: 10.1016/b978-0-444-63462-7.00002-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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11
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Hebebrand J, Albayrak Ö, Adan R, Antel J, Dieguez C, de Jong J, Leng G, Menzies J, Mercer JG, Murphy M, van der Plasse G, Dickson SL. “Eating addiction”, rather than “food addiction”, better captures addictive-like eating behavior. Neurosci Biobehav Rev 2014; 47:295-306. [DOI: 10.1016/j.neubiorev.2014.08.016] [Citation(s) in RCA: 244] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 08/25/2014] [Accepted: 08/28/2014] [Indexed: 01/18/2023]
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12
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13
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Rochon K, Proteau-Gagné A, Bourassa P, Nadon JF, Côté J, Bournival V, Gobeil F, Guérin B, Dory YL, Gendron L. Preparation and evaluation at the delta opioid receptor of a series of linear leu-enkephalin analogues obtained by systematic replacement of the amides. ACS Chem Neurosci 2013; 4:1204-16. [PMID: 23650868 PMCID: PMC3750687 DOI: 10.1021/cn4000583] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 05/07/2013] [Indexed: 12/16/2022] Open
Abstract
Leu-enkephalin analogues, in which the amide bonds were sequentially and systematically replaced either by ester or N-methyl amide bonds, were prepared using classical organic chemistry as well as solid phase peptide synthesis (SPPS). The peptidomimetics were characterized using competition binding, ERK1/2 phosphorylation, receptor internalization, and contractility assays to evaluate their pharmacological profile over the delta opioid receptor (DOPr). The lipophilicity (LogD7.4) and plasma stability of the active analogues were also measured. Our results revealed that the last amide bond can be successfully replaced by either an ester or an N-methyl amide bond without significantly decreasing the biological activity of the corresponding analogues when compared to Leu-enkephalin. The peptidomimetics with an N-methyl amide function between residues Phe and Leu were found to be more lipophilic and more stable than Leu-enkephalin. Findings from the present study further revealed that the hydrogen-bond donor properties of the fourth amide of Leu-enkephalin are not important for its biological activity on DOPr. Our results show that the systematic replacement of amide bonds by isosteric functions represents an efficient way to design and synthesize novel peptide analogues with enhanced stability. Our findings further suggest that such a strategy can also be useful to study the biological roles of amide bonds.
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Affiliation(s)
- Kristina Rochon
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Arnaud Proteau-Gagné
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Philippe Bourassa
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Jean-François Nadon
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Jérome Côté
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Véronique Bournival
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Fernand Gobeil
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Brigitte Guérin
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Yves L. Dory
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
| | - Louis Gendron
- Département de Physiologie
et Biophysique, Laboratoire de Synthèse Supramoléculaire, Département
de Chimie, Département de pharmacologie, and Département de Médecine
Nucléaire et Radiobiologie, Institut de Pharmacologie, Université de Sherbrooke, 3001, 12 Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada
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Touati-Jallabe Y, Bojnik E, Legrand B, Mauchauffée E, Chung NN, Schiller PW, Benyhe S, Averlant-Petit MC, Martinez J, Hernandez JF. Cyclic enkephalins with a diversely substituted guanidine bridge or a thiourea bridge: synthesis, biological and structural evaluations. J Med Chem 2013; 56:5964-5973. [PMID: 23822516 DOI: 10.1021/jm4008592] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Two series of 22 and 15 atom cyclic enkephalins incorporating a diversely substituted guanidine bridge have been prepared to assess the potential effect of the bridge substitutions on their opioid activity profile. The most notable results were obtained with the shortest cyclic analogues, which showed a significant variation of their binding affinity toward μ and δ opioid receptors in relation to bridge substitution. NMR studies were performed to rationalize these data. Some small analogues were found to exist as at least one major and one minor stable forms, which could be separated by chromatography. In particular, the compounds 13 and 14 with a cyclic substituent were separated in three isomers and the basis of this multiplicity was explored by 2D NMR spectroscopy. All compounds were agonists with slight selectivity for the μ opioid receptor. Compounds 7a (thiourea bridge) and 10a (N-Me-guanidine bridge) showed nanomolar affinity toward μ receptor, the latter being the more selective for this receptor (40-fold).
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Affiliation(s)
- Youness Touati-Jallabe
- Institut des Biomolécules Max Mousseron, CNRS UMR 5247, Université Montpellier 1, Université Montpellier 2, Faculté de Pharmacie, 15 Avenue Charles Flahault, 34093 Montpellier cedex 05, France
| | - Engin Bojnik
- Biological Research Center, Institute of Biochemistry, POB 521, H-6702 Szeged, Hungary
| | - Baptiste Legrand
- Laboratoire de Chimie Physique Macromoléculaire, CNRS UMR 7568, Université de Lorraine, 1 rue Grandville, 54001 Nancy Cedex, France
| | - Elodie Mauchauffée
- Institut des Biomolécules Max Mousseron, CNRS UMR 5247, Université Montpellier 1, Université Montpellier 2, Faculté de Pharmacie, 15 Avenue Charles Flahault, 34093 Montpellier cedex 05, France
| | - Nga N Chung
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, Quebec H2W 1R7, Canada
| | - Peter W Schiller
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, Quebec H2W 1R7, Canada.,Department of Pharmacology, Université de Montréal, Montreal, Quebec H3C 3J7, Canada
| | - Sandor Benyhe
- Biological Research Center, Institute of Biochemistry, POB 521, H-6702 Szeged, Hungary
| | - Marie-Christine Averlant-Petit
- Laboratoire de Chimie Physique Macromoléculaire, CNRS UMR 7568, Université de Lorraine, 1 rue Grandville, 54001 Nancy Cedex, France
| | - Jean Martinez
- Institut des Biomolécules Max Mousseron, CNRS UMR 5247, Université Montpellier 1, Université Montpellier 2, Faculté de Pharmacie, 15 Avenue Charles Flahault, 34093 Montpellier cedex 05, France
| | - Jean-Franćois Hernandez
- Institut des Biomolécules Max Mousseron, CNRS UMR 5247, Université Montpellier 1, Université Montpellier 2, Faculté de Pharmacie, 15 Avenue Charles Flahault, 34093 Montpellier cedex 05, France
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15
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Nefzi A. Hantzsch based macrocyclization approach for the synthesis of thiazole containing cyclopeptides. Methods Mol Biol 2013; 1081:1-11. [PMID: 24014430 DOI: 10.1007/978-1-62703-652-8_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
An innovative macrocyclization approach via high-yielding solid-phase intramolecular thioalkylation reaction is described. The reaction of S-nucleophiles with newly generated N-terminal 4-chloromethyl thiazoles leads to the desired cyclic products in high purities and good yields.
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Affiliation(s)
- Adel Nefzi
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL, USA
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16
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Haghighatnia Y, Balalaie S, Bijanzadeh HR. Designing and Synthesis of Novel Amidated Fentanyl Analogs. Helv Chim Acta 2012. [DOI: 10.1002/hlca.201100392] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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17
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Opioid system and Alzheimer's disease. Neuromolecular Med 2012; 14:91-111. [PMID: 22527793 DOI: 10.1007/s12017-012-8180-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 04/04/2012] [Indexed: 12/15/2022]
Abstract
The opioid system may be involved in the pathogenesis of AD, including cognitive impairment, hyperphosphorylated tau, Aβ production, and neuroinflammation. Opioid receptors influence the regulation of neurotransmitters such as acetylcholine, norepinephrine, GABA, glutamate, and serotonin which have been implicated in the pathogenesis of AD. Opioid system has a close relation with Aβ generation since dysfunction of opioid receptors retards the endocytosis and degradation of BACE1 and γ-secretase and upregulates BACE1 and γ-secretase, and subsequently, the production of Aβ. Conversely, activation of opioid receptors increases the endocytosis of BACE1 and γ-secretase and downregulates BACE1 and γ-secretase, limiting the production of Aβ. The dysfunction of opioid system (opioid receptors and opioid peptides) may contribute to hyperphosphorylation of tau and neuroinflammation, and accounts for the degeneration of cholinergic neurons and cognitive impairment. Thus, the opioid system is potentially related to AD pathology and may be a very attractive drug target for novel pharmacotherapies of AD.
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18
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2',6'-dimethylphenylalanine: a useful aromatic amino Acid surrogate for tyr or phe residue in opioid peptides. INTERNATIONAL JOURNAL OF MEDICINAL CHEMISTRY 2012; 2012:498901. [PMID: 25954528 PMCID: PMC4412257 DOI: 10.1155/2012/498901] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Revised: 03/15/2012] [Accepted: 03/18/2012] [Indexed: 11/17/2022]
Abstract
Two aromatic amino acids, Tyr(1) and Phe(3) or Phe(4), are important structural elements in opioid peptides because they interact with opioid receptors. The usefulness of an artificial amino acid residue 2',6'-dimethylphenylalanine (Dmp) was investigated as an aromatic amino acid surrogate for several opioid peptides, including enkephalin, dermorphin, deltorphin, endomorphin, dynorphin A, and nociceptin peptides. In most peptides, substitutions of Phe(3) by a Dmp residue produced analogs with improved receptor-binding affinity and selectivity, while the same substitution of Phe(4) induced markedly reduced receptor affinity and selectivity. Interestingly, replacement of Tyr(1) by Dmp produced analogs with unexpectedly high affinity or produced only a slight drop in receptor affinity and bioactivity for most peptides. Thus, Dmp is also a useful surrogate for the N-terminal Tyr residue in opioid peptides despite the lack of a phenolic hydroxyl group, which is considered necessary for opioid activity. The Dmp(1)-substituted analogs are superior to 2',6'-dimethyltyrosine (Dmt)(1)-substituted analogs for high receptor selectivity since the latter generally have poor receptor selectivity. Thus, Dmp is very useful as an aromatic amino acid surrogate in opioid peptides and may be useful for developing other novel peptide mimetics with high receptor specificity.
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19
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Mollica A, Pinnen F, Stefanucci A, Feliciani F, Campestre C, Mannina L, Sobolev AP, Lucente G, Davis P, Lai J, Ma SW, Porreca F, Hruby VJ. The cis-4-amino-L-proline residue as a scaffold for the synthesis of cyclic and linear endomorphin-2 analogues. J Med Chem 2012; 55:3027-35. [PMID: 22394120 DOI: 10.1021/jm201402v] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Endomorphin-2 (EM-2: Tyr-Pro-Phe-Phe-NH(2)) is an endogenous tetrapeptide that combines potency and efficacy with high affinity and selectivity toward the μ opioid receptor, the most responsible for analgesic effects in the central nervous system. The presence of the Pro(2) represents a crucial factor for the ligand structural and conformational properties. Proline is in fact an efficient stereochemical spacer, capable of inducing favorable spatial orientation of aromatic rings, a key factor for ligand recognition and interaction with receptors. Here the Pro(2) has been replaced by 4(S)-NH(2)-2(S)-proline (cAmp), a proline/GABA cis-chimera residue. This bivalent amino acid maintains the capacity to influenc the tetrapeptide conformation and offers the opportunity to generate new linear models and unusually constrained cyclic analogues characterized by an N-terminal Tyr bearing a free α-amino group. The results indicate that the new analogues do not show affinity for both δ and κ opioid receptors and bind only poorly to the μ receptors (for cyclopeptide 9: K(i)(μ) = 660 nM; GPI (IC(50)) = 1.4% at 1 μM; for linear tetrapeptide acid 13: K(i)(μ) = 2000 nM; GPI (IC(50)) = 0% at 1 μM; for linear tetrapeptide amide 15: K(i)(μ) = 310 nM; GPI (IC(50)) = 894 nM).
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Affiliation(s)
- Adriano Mollica
- Dipartimento di Scienze del Farmaco, Università di Chieti-Pescara G. d'Annunzio, Via dei Vestini 31, 66100 Chieti, Italy.
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20
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Berezowska I, Lemieux C, Chung NN, Ding J, Schiller PW. Novel TIPP (H-Tyr-Tic-Phe-Phe-OH) analogues displaying a wide range of efficacies at the δ opioid receptor. Discovery of two highly potent and selective δ opioid agonists. Bioorg Med Chem Lett 2012; 22:1899-902. [PMID: 22325949 DOI: 10.1016/j.bmcl.2012.01.063] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 01/15/2012] [Accepted: 01/17/2012] [Indexed: 10/14/2022]
Abstract
Analogues of the δ opioid antagonist peptide TIPP (H-Tyr-Tic-Phe-Phe-OH; Tic=1,2,3,4-tetrahydroisoquinoline3-carboxylic acid) containing various 4'-[N-(alkyl or aralkyl)carboxamido]phenylalanine analogues in place of Tyr(1) were synthesized. The compounds showed subnanomolar or low nanomolar δ opioid receptor binding affinity and various efficacy at the δ receptor (antagonism, partial agonism, full agonism) in the [(35)S]GTPγS binding assay. Two analogues, [1-Ncp(1)]TIPP (1-Ncp=4'-[N-(2-(naphthalene-1-yl)ethyl)carboxamido]phenylalanine) and [2-Ncp(1)]TIPP (2-Ncp=4'-[N-(2-(naphthalene-2-yl)ethyl)carboxamido]phenylalanine), were identified as potent and selective δ opioid agonists.
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Affiliation(s)
- Irena Berezowska
- Laboratory of Chemical Biology and Peptide Research, Clinical Research Institute of Montreal, 110 Pine Avenue West, Montreal, QC, Canada H2W 1R7
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21
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Vandormael B, De Wachter R, Martins JC, Hendrickx PMS, Keresztes A, Ballet S, Mallareddy JR, Tóth F, Tóth G, Tourwé D. Asymmetric Synthesis and Conformational Analysis by NMR Spectroscopy and MD of Aba- and α-MeAba-Containing Dermorphin Analogues. ChemMedChem 2011; 6:2035-47. [DOI: 10.1002/cmdc.201100314] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Indexed: 11/10/2022]
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22
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Gentilucci L, Tolomelli A, De Marco R, Spampinato S, Bedini A, Artali R. The Inverse Type II β-Turn on D-Trp-Phe, a Pharmacophoric Motif for MOR Agonists. ChemMedChem 2011; 6:1640-53. [DOI: 10.1002/cmdc.201100169] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2011] [Revised: 05/19/2011] [Indexed: 11/12/2022]
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23
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Liu WX, Wang R. Endomorphins: potential roles and therapeutic indications in the development of opioid peptide analgesic drugs. Med Res Rev 2011; 32:536-80. [DOI: 10.1002/med.20222] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
| | - Rui Wang
- Key Laboratory of Preclinical Study for New Drugs of Gansu Province; School of Basic Medical Sciences; Institute of Biochemistry and Molecular Biology; State Key Laboratory of Applied Organic Chemistry; Lanzhou University; Lanzhou China
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24
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Datta S, Kazmaier U. Stereoselective palladium-catalyzed allylic alkylations of peptideamide enolates. Org Biomol Chem 2011; 9:872-80. [DOI: 10.1039/c0ob00628a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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25
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Cros CD, Toth I, Blanchfield JT. Lipophilic derivatives of leu-enkephalinamide: in vitro permeability, stability and in vivo nasal delivery. Bioorg Med Chem 2010; 19:1528-34. [PMID: 21273080 DOI: 10.1016/j.bmc.2010.12.042] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Revised: 12/10/2010] [Accepted: 12/21/2010] [Indexed: 11/19/2022]
Abstract
Leu-enkephalin is an endogenous pain modulating opioid pentapeptide. Its development as a potential pharmaceutic has been hampered by poor membrane permeability and susceptibility to enzymatic degradation. The addition of an unnatural amino acid containing a lipidic side chain at the N-terminus and the modification of the C-terminus to a carboxyamide was performed to enhance the nasal delivery of the peptide. Two lipidic derivatives with varying side chain lengths (C(8)-Enk-NH(2) (1), C(12)-Enk-NH(2) (2)) and their acetylated analogues were successfully synthesised. Caco-2 cell monolayer permeability and Caco-2 cell homogenate stability assays were performed. C(8)-Enk-NH(2) (1) and its acetylated analogue Ac-C8-Enk-NH(2) (3) exhibited apparent permeabilities (mean±SD) of 2.51±0.75×10(-6)cm/s and 1.06±0.62×10(-6), respectively. C12-Enk-NH(2) (2) exhibited an apparent permeability of 2.43±1.26×10(-6) cm/s while Ac-C12-Enk-NH(2) (4) was not permeable through the Caco-2 monolayers due to its poor solubility. All analogues exhibited improved Caco-2 homogenate stability compared to Leu-Enk-NH(2) with t(½) values of: C8-Enk-NH(2) (1): 31.7 min, C(12)-Enk-NH(2) (2): 14.7 min, Ac-C8-Enk-NH(2) (3): 83 min, Ac-C(12)-Enk-NH(2) (4): 27 min. However, plasma stability assays revealed that the diastereoisomers of C8-Enk-NH(2) (1) did not degrade at the same rate, with the l isomer (t(1/2)=8.9 min) degrading into Leu-enkephalinamide and then des-Tyr-Leu-Enk-NH(2), whereas the d isomer was stable (t(1/2)=120 min). In vivo nasal administration of C(8)-Enk-NH(2) to male rats resulted in concentrations of 5.9±1.84×10(-2) μM in the olfactory bulbs, 1.35±1.01×10(-2) μM in the brain and 6.53±1.87×10(-3) μM in the blood 10 min after administration.
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Affiliation(s)
- Cécile D Cros
- School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane 4072, Australia
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26
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Davis MP. Opioid receptor targeting ligands for pain management: a review and update. Expert Opin Drug Discov 2010; 5:1007-22. [DOI: 10.1517/17460441.2010.511473] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Structural comparison of μ-opioid receptor selective peptides confirmed four parameters of bioactivity. J Mol Graph Model 2010; 28:495-505. [DOI: 10.1016/j.jmgm.2009.11.006] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Revised: 11/24/2009] [Accepted: 11/27/2009] [Indexed: 11/18/2022]
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29
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Geary TG. Nonpeptide ligands for peptidergic G protein-coupled receptors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 692:10-26. [PMID: 21189672 DOI: 10.1007/978-1-4419-6902-6_2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Neuropeptides play essential roles in many physiological systems in vertebrates and invertebrates. Peptides per se are difficult to use as therapeutic agents, as they are generally very unstable in biological fluid environments and cross biological membranes poorly. Recognition that nonpeptide ligands for peptide receptors have clinical utility came from the discovery that opiates (such as morphine) act by binding to G protein-coupled receptors (GPCRs) for which the endogenous ligands are a family of neuropeptides (enkephalins and endorphins). Basic research has revealed a very large number of distinct neuropeptides that influence virtually every aspect of mammalian physiology and considerable effort has been expended in the pursuit of new drugs that act through peptidergic signaling systems. Although useful drugs have been found to affect various aspects ofneuropeptide biology, most work has been devoted to the discovery of nonpeptide ligands that act as agonists or antagonists at peptidergic GPCRs. Similar opportunities are apparent for the discovery of nonpeptide ligands that act on invertebrate GPCRs. A consideration of the knowledge gained from the process as conducted for mammalian peptidergic systems can inform and illuminate promising strategies for the discovery of new drugs for the treatment and control of pests and parasites.
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Affiliation(s)
- Timothy G Geary
- Institute of Parasitology, McGill University, 21111 Lakeshore Road, Ste-Anne-de-Bellevue, QC, Canada.
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30
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Fang WJ, Cui Y, Murray TF, Aldrich JV. Design, synthesis, and pharmacological activities of dynorphin A analogues cyclized by ring-closing metathesis. J Med Chem 2009; 52:5619-25. [PMID: 19715279 DOI: 10.1021/jm900577k] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dynorphin A (Dyn A) is an endogenous ligand for kappa opioid receptors. To restrict the conformational mobility, we synthesized several cyclic Dyn A-(1-11)NH(2) analogues on solid phase utilizing ring-closing metathesis (RCM) between the side chains of allylglycine (AllGly) residues incorporated in positions 2, 5, and/or 8. Cyclizations between the side chains of AllGly gave reasonable yields (56-74%) of all of the desired cyclic peptides. Both the cis and trans isomers were obtained for all of the cyclic peptides, with the ratio of cis to trans isomers depending on the position and stereochemistry of the AllGly. Most of the cyclic Dyn A-(1-11)NH(2) analogues examined exhibit low nanomolar binding affinity for kappa opioid receptors (K(i) = 0.84-11 nM). In two of the three cases, the configuration of the double bond has a significant influence on the opioid receptor affinities and agonist potency. All of the peptides inhibited adenylyl cyclase activity in a concentration-dependent manner with full or close to full agonist activity. These potent Dyn A analogues are the first ones cyclized by RCM.
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Affiliation(s)
- Wei-Jie Fang
- Department of Medicinal Chemistry, The University of Kansas, Lawrence, Kansas 66045, USA
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Grauer A, Späth A, Ma D, König B. Metal-catalyzed derivatization of C(alpha)-tetrasubstituted amino acids and their use in the synthesis of cyclic peptides. Chem Asian J 2009; 4:1134-40. [PMID: 19472262 DOI: 10.1002/asia.200900033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
C(alpha)-tetrasubstituted amino acids are important building blocks in the design and preparation of novel peptidomimetics. We report on the functionalization of the C(alpha)-tetrasubstituted THF amino acid rac-5 by copper(I) catalyzed N-arylation reactions. The aryl bromide substituent of rac-5 is replaced by a variety of aliphatic and aromatic amines. Intramolecular N-arylation yielded only small amounts of a cyclic tripeptide 2, whereas cyclic tripeptide ethers 4 and 50 were obtained in an enantiomerically pure form from a palladium(0)-catalyzed intramolecular O-arylation.
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Affiliation(s)
- Andreas Grauer
- Institut für Organische Chemie, Universität Regensburg, 93040 Regensburg, Germany
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32
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Lee HK, Smith MD, Smith BJ, Grussendorf J, Xu L, Gillies RJ, White HS, Bulaj G. Anticonvulsant Met-enkephalin analogues containing backbone spacers reveal alternative non-opioid signaling in the brain. ACS Chem Biol 2009; 4:659-71. [PMID: 19634861 DOI: 10.1021/cb900045c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Prosthesis of non-critical parts of a polypeptide backbone is an attractive strategy to simplify bioactive peptides. This approach was applied to an opioid neuropeptide, Met-enkephalin, in which two adjacent Gly2-Gly3 residues were replaced with a series of non-peptidic backbone spacers varying in length and/or physicochemical properties. The backbone spacers did not affect the overall structural properties of the analogues, but they did dramatically reduce their affinities and agonist activities toward delta- and mu-opioid receptors. Molecular modeling suggested that the decrease of the affinity of Met-enkephalin to delta-opioid receptor could be accounted for by the loss of a single hydrogen bond. Remarkably, the analogues containing the most isostere spacers retained potent antinociceptive and anticonvulsant properties that were comparable to that of the endogenous peptide. This unexpected high in vivo potency could not be accounted for by an increase in metabolic stability. Moreover, the antiepileptic activity could not be reversed by opioid receptor antagonists. In summary, the results obtained with the analogues containing backbone spacers suggest a novel mechanism for seizure control in the brain that involves alternative non-opioid signaling.
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Affiliation(s)
| | - Misty D. Smith
- Department of Pharmacology and Toxicology, The University of Utah, 421 Wakara Way, Suite 360, Salt Lake City, Utah 84108
| | - Brian J. Smith
- The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
| | - Joel Grussendorf
- Department of Pharmacology and Toxicology, The University of Utah, 421 Wakara Way, Suite 360, Salt Lake City, Utah 84108
| | - Liping Xu
- Department of Radiology
- Department of Biochemistry and Molecular Biophysics, Arizona Health Sciences Center, University of Arizona, Tucson, Arizona 85724
| | - Robert J. Gillies
- Department of Radiology
- Department of Biochemistry and Molecular Biophysics, Arizona Health Sciences Center, University of Arizona, Tucson, Arizona 85724
| | - H. Steve White
- Department of Pharmacology and Toxicology, The University of Utah, 421 Wakara Way, Suite 360, Salt Lake City, Utah 84108
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33
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Grauer AA, Cabrele C, Zabel M, König B. Stable right- and left-handed peptide helices containing C(alpha)-tetrasubstituted alpha-amino acids. J Org Chem 2009; 74:3718-26. [PMID: 19354242 DOI: 10.1021/jo900222g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Short peptidomimetics with stable secondary structures in solution are of interest for applications in chemistry, biology, and medicine. One way to rigidify the backbone of a peptide is the use of cyclic C(alpha)-tetrasubstituted alpha-amino acids (TAAs) like compound 14. The structures resulting from the incorporation of this unnatural amino acid into peptides were investigated. In total, 13 different peptides with a length of up to eight residues and alternating sequences of TAA 14 and (S)- or (R)-valine were synthesized. Their structures were characterized by X-ray diffraction analysis and NMR and CD measurements showing that the all-S-backbone-configured peptides 5 and 6 (SS)(2-3) form right-handed 3(10)-helices, while the all-R-configured peptides 11-13 (RR)(2-4) form left-handed 3(10)-helices in the solid state and solution.
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Affiliation(s)
- Andreas A Grauer
- Institute for Organic Chemistry, University of Regensburg, D-93040 Regensburg, Germany
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34
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Torres-Reveron A, Williams TJ, Chapleau JD, Waters EM, McEwen BS, Drake CT, Milner TA. Ovarian steroids alter mu opioid receptor trafficking in hippocampal parvalbumin GABAergic interneurons. Exp Neurol 2009; 219:319-27. [PMID: 19505458 DOI: 10.1016/j.expneurol.2009.06.001] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Accepted: 06/01/2009] [Indexed: 10/20/2022]
Abstract
The endogenous hippocampal opioid systems are implicated in learning associated with drug use. Recently, we showed that ovarian hormones regulate enkephalin levels in the mossy fiber pathway. This pathway overlaps with parvalbumin (PARV)-basket interneurons that contain the enkephalin-activated mu opioid receptors (MORs) and are important for controlling the "temporal timing" of granule cells. Here, we evaluated the influence of ovarian steroids on the trafficking of MORs in PARV interneurons. Two groups of female rats were analyzed: cycling rats in proestrus (relatively high estrogens) or diestrus; and ovariectomized rats euthanized 6, 24 or 72 h after estradiol benzoate (10 microg, s.c.) administration. Dorsal hippocampal sections were dually immunolabeled for MOR and PARV and examined by light and electron microscopy. As in males, in females MOR-immunoreactivity (-ir) was in numerous PARV-labeled perikarya, dendrites and terminals in the dentate hilar region. Variation in ovarian steroid levels altered the subcellular distribution of MORs in PARV-labeled dendrites but not terminals. In normal cycling rats, MOR-gold particles on the plasma membrane of small PARV-labeled dendrites (area <1 microm2) had higher density in proestrus rats than in diestrus rats. Likewise, in ovariectomized rats MORs showed higher density on the plasma membrane of small PARV-labeled dendrites 72 h after estradiol exposure. The number of PARV-labeled cells was not affected by estrous cycle phase or estrogen levels. These results demonstrate that estrogen levels positively regulate the availability of MORs on GABAergic interneurons in the dentate gyrus, suggesting cooperative interaction between opioids and estrogens in modulating principal cell excitability.
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Affiliation(s)
- Annelyn Torres-Reveron
- Division of Neurobiology, Department of Neurology and Neuroscience, Weill Cornell Medical College, 407 East 61st Street, New York, NY 10065, USA.
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35
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Gentilucci L, Cardillo G, Tolomelli A, De Marco R, Garelli A, Spampinato S, Spartà A, Juaristi E. Synthesis and Conformational Analysis of Cyclotetrapeptide Mimetic β-Turn Templates and Validation as 3D Scaffolds. ChemMedChem 2009; 4:517-23. [DOI: 10.1002/cmdc.200800407] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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36
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Grauer AA, König B. Synthesis of new Calpha-tetrasubstituted alpha-amino acids. Beilstein J Org Chem 2009; 5:5. [PMID: 19259341 PMCID: PMC2649440 DOI: 10.3762/bjoc.5.5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Accepted: 02/05/2009] [Indexed: 11/23/2022] Open
Abstract
Cα-Tetrasubstituted α-amino acids are important building blocks for the synthesis of peptidemimetics with stabilized secondary structure, because of their ability to rigidify the peptide backbone. Recently our group reported a new class of cyclic Cα-tetrasubstituted tetrahydrofuran α-amino acids prepared from methionine and aromatic aldehydes. We now report the extension of this methodology to aliphatic aldehydes. Although such aldehydes are prone to give aldol products under the reaction conditions used, we were able to obtain the target cyclic amino acids in low to moderate yields and in some cases with good diastereoselectivity.
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Affiliation(s)
- Andreas A Grauer
- Institute for Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93040 Regensburg, Germany
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37
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Moore SB, Grant M, Rew Y, Bosa E, Fabbri M, Kumar U, Goodman M. Synthesis and biologic activity of conformationally constrained analogs of L-363,301. ACTA ACUST UNITED AC 2008; 66:404-22. [PMID: 16316457 DOI: 10.1111/j.1399-3011.2005.00309.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report the synthesis, biological activity and conformational analysis of analogs of the cyclic hexapeptide L-363,301, c[Pro6-Phe7-D-Trp8-Lys9-Thr10-Phe11] (numbering as in the native hormone somatostatin-14). The d-Trp in position 8 was replaced with (2R,3S)- and (2R,3R)-beta-MeTrp respectively, with an added methyl group in the beta position of Trp. The objective of our study was to determine the potency and selectivity generated by the added constraint in the beta position of the d-Trp upon binding to human somatostatin receptors hsst1-5. We synthesized the building blocks enantioselectively and incorporated them into the peptides by SPPS. Competition binding assays revealed that both compounds 2 and 3 were selective for hsst2 over hsst5. The (2R,3S) analog 2 was approximately 30 times more potent at hsst2 than the (2R,3R) analog 3. Interestingly, the (2R,3R) compound showed no binding affinity at hsst5.
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Affiliation(s)
- S B Moore
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0343, USA.
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Moriyama K, Sakai H, Kawabata T. Direct Asymmetric Intramolecular Alkylation of β-Alkoxy-α-amino Esters via Memory of Chirality. Org Lett 2008; 10:3883-6. [DOI: 10.1021/ol801213c] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Katsuhiko Moriyama
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Hiroki Sakai
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Takeo Kawabata
- Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan
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Agnes RS, Ying J, Kövér KE, Lee YS, Davis P, Ma SW, Badghisi H, Porreca F, Lai J, Hruby VJ. Structure-activity relationships of bifunctional cyclic disulfide peptides based on overlapping pharmacophores at opioid and cholecystokinin receptors. Peptides 2008; 29:1413-23. [PMID: 18502541 PMCID: PMC2601673 DOI: 10.1016/j.peptides.2008.03.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 03/26/2008] [Accepted: 03/27/2008] [Indexed: 11/24/2022]
Abstract
Prolonged opioid exposure increases the expression of cholecystokinin (CCK) and its receptors in the central nervous system (CNS), where CCK may attenuate the antinociceptive effects of opioids. The complex interactions between opioid and CCK may play a role in the development of opioid tolerance. We designed and synthesized cyclic disulfide peptides and determined their agonist properties at opioid receptors and antagonist properties at CCK receptors. Compound 1 (Tyr-c[d-Cys-Gly-Trp-Cys]-Asp-Phe-NH(2)) showed potent binding and agonist activities at delta and mu opioid receptors but weak binding to CCK receptors. The NMR structure of the lead compound displayed similar conformational features of opioid and CCK ligands.
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Affiliation(s)
- Richard S. Agnes
- Department of Chemistry, University of Arizona, Tucson, AZ 85721
| | - Jinfa Ying
- Department of Chemistry, University of Arizona, Tucson, AZ 85721
| | - Katalin E. Kövér
- Department of Chemistry, University of Debrecen, H-4010 Debrecen, P.O. Box 21, Egyetem tér 1, Hungary
| | - Yeon Sun Lee
- Department of Chemistry, University of Arizona, Tucson, AZ 85721
| | - Peg Davis
- Department of Pharmacology, University of Arizona, Tucson, AZ 85724
| | - Shou-wu Ma
- Department of Pharmacology, University of Arizona, Tucson, AZ 85724
| | - Hamid Badghisi
- Department of Pharmacology, University of Arizona, Tucson, AZ 85724
| | - Frank Porreca
- Department of Pharmacology, University of Arizona, Tucson, AZ 85724
| | - Josephine Lai
- Department of Pharmacology, University of Arizona, Tucson, AZ 85724
| | - Victor J. Hruby
- Department of Chemistry, University of Arizona, Tucson, AZ 85721
- To whom correspondence should be addressed: Victor J. Hruby, Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA. Phone: (520) 621-6332. Fax: (520) 621-8407.,
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Gentilucci L, Squassabia F, Demarco R, Artali R, Cardillo G, Tolomelli A, Spampinato S, Bedini A. Investigation of the interaction between the atypical agonist c[YpwFG] and MOR. FEBS J 2008; 275:2315-37. [DOI: 10.1111/j.1742-4658.2008.06386.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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41
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Gentilucci L, Cardillo G, Tolomelli A, Spampinato S, Sparta A, Squassabia F. Cyclotetrapeptide Mimics Based on a 13-Membered, Partially Modified Retro-Inverso Structure. European J Org Chem 2008. [DOI: 10.1002/ejoc.200700932] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Green BR, Catlin P, Zhang MM, Fiedler B, Bayudan W, Morrison A, Norton RS, Smith BJ, Yoshikami D, Olivera BM, Bulaj G. Conotoxins containing nonnatural backbone spacers: cladistic-based design, chemical synthesis, and improved analgesic activity. ACTA ACUST UNITED AC 2007; 14:399-407. [PMID: 17462575 DOI: 10.1016/j.chembiol.2007.02.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2006] [Revised: 02/09/2007] [Accepted: 02/20/2007] [Indexed: 11/23/2022]
Abstract
Disulfide-rich neurotoxins from venomous animals continue to provide compounds with therapeutic potential. Minimizing neurotoxins often results in removal of disulfide bridges or critical amino acids. To address this drug-design challenge, we explored the concept of disulfide-rich scaffolds consisting of isostere polymers and peptidic pharmacophores. Flexible spacers, such as amino-3-oxapentanoic or 6-aminohexanoic acids, were used to replace conformationally constrained parts of a three-disulfide-bridged conotoxin, SIIIA. The peptide-polymer hybrids, polytides, were designed based on cladistic identification of nonconserved loci in related peptides. After oxidative folding, the polytides appeared to be better inhibitors of sodium currents in dorsal root ganglia and sciatic nerves in mice. Moreover, the polytides appeared to be significantly more potent and longer-lasting analgesics in the inflammatory pain model in mice, when compared to SIIIA. The resulting polytides provide a promising strategy for transforming disulfide-rich peptides into therapeutics.
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Affiliation(s)
- Brad R Green
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA
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Lee YS, Petrov R, Park CK, Ma SW, Davis P, Lai J, Porreca F, Vardanyan R, Hruby VJ. Development of novel enkephalin analogues that have enhanced opioid activities at both mu and delta opioid receptors. J Med Chem 2007; 50:5528-32. [PMID: 17927164 DOI: 10.1021/jm061465o] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Enkephalin analogues with a 4-anilidopiperidine scaffold have been designed and synthesized to achieve therapeutic benefit for the treatment of pain due to mixed mu and delta opioid agonist activities. Ligand 16, in which a Dmt-substituted enkephalin-like structure was linked to the N-phenyl-N-piperidin-4-yl propionamide moiety, showed very high binding affinities (0.4 nM) at mu and delta receptors with an increased hydrophobicity (aLogP = 2.96). This novel lead compound was found to have very potent agonist activities in MVD (1.8 nM) and GPI (8.5 nM) assays.
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Affiliation(s)
- Yeon Sun Lee
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA
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Maity P, Zabel M, König B. Tetrahydrofuran Calpha-tetrasubstituted amino acids: two consecutive beta-turns in a crystalline linear tripeptide. J Org Chem 2007; 72:8046-53. [PMID: 17877403 DOI: 10.1021/jo701423w] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis of tetrahydrofuran Calpha-tetrasubstituted amino acids (TAAs) and their effect on the conformation in small peptides are reported. The synthesis starts from the protein amino acid methionine, which is protected at the C and N terminus and converted into the corresponding sulfonium salt by alkylation. Simple base treatment in the presence of an aryl aldehyde leads to the formation of tetrahydrofuran tetrasubstituted Calpha-amino acids in a highly diastereoselective (trans/cis ratio up to 97:3) reaction with moderate to good yields (35-78%) depending on the aldehyde used. Palladium-catalyzed coupling reactions allow a subsequent further functionalization of the TAA. The R,S,S-TAA-Ala dipeptide amide adopts a beta-turn type I conformation, whereas its S,R,S isomer does not. The R,S,S-Gly-TAA-Ala tripeptide amide shows in the solid state and in solution a conformation of two consecutive beta-turn type III structures, stabilized by i+3-->i intramolecular hydrogen bonds.
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Affiliation(s)
- Prantik Maity
- Institut für Organische Chemie, Universität Regensburg, D-93040 Regensburg, Germany
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Yu Y, Shao X, Wang CL, Liu HM, Cui Y, Fan YZ, Liu J, Wang R. In vitro and in vivo characterization of opioid activities of endomorphins analogs with novel constrained C-terminus: evidence for the important role of proper spatial disposition of the third aromatic ring. Peptides 2007; 28:859-70. [PMID: 17276550 DOI: 10.1016/j.peptides.2007.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2006] [Revised: 01/08/2007] [Accepted: 01/08/2007] [Indexed: 10/23/2022]
Abstract
In the present study, the C-terminus of endomorphin (Tyr(1)-Pro(2)-Trp/Phe(3)-Phe(4)-NH(2), EMs) analogs [Xaa(4)-R]EMs, modified by substitution of a non-aromatic residue for Phe(4) and ending up with -NH-benzyl, were designed to generate an atypical conformationally constrained peptide set. We investigated the effects of these analogs on the opioid receptors affinity, guinea pig ileum (GPI) and mouse vas deferens (MVD) activity, system arterial pressure (SAP), heart rate (HR), antinociception and colonic motility. Analogs 5 ([D-V(4)-Bzl]EM1) and 10 ([D-V(4)-Bzl]EM2), which exhibit appropriate spatial orientations of the third aromatic ring, were about 3-4 times more potent than their parents both in vivo and in vitro. However, a drastic loss of activity was found in analogs 2 ([A(4)-Bzl]EM1) and 7 ([A(4)-Bzl]EM2), which possess improper spatial orientations of the third aromatic ring. Interestingly, analog 7 or 3 ([G(4)-Bzl]EM1), when injected intravenously (i.v.), produced significantly different changes in SAP from their parents. Surprisingly, analog 4 displayed relatively higher vasodepressor activity but significantly less potent colonic contractile activity than analog 5. This may be elicited by the differences in the spatial disposition of the third aromatic ring, which were verified by molecular modeling. Our results indicate that the proper spatial disposition of the third aromatic ring plays an important role in the regulation of pharmacological activities of EMs.
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Affiliation(s)
- Ye Yu
- Institute of Biochemistry and Molecular Biology, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, 222 Tian Shui South Road, Lanzhou 730000, China
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Yu Y, Shao X, Cui Y, Liu HM, Wang CL, Fan YZ, Liu J, Dong SL, Cui YX, Wang R. Structure–Activity Study on the Spatial Arrangement of the Third Aromatic Ring of Endomorphins 1 and 2 Using an Atypical Constrained C Terminus. ChemMedChem 2007; 2:309-17. [PMID: 17285661 DOI: 10.1002/cmdc.200600274] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The discovery of endomorphins (EMs) has opened the possibility of searching for new analgesics. However, the design of peptide analgesics has proven to be very difficult as a result of their conformational flexibility and a lack of clarity in structure-activity relationships (SAR). In EMs, the amino acid side chains exhibit considerable conformational flexibility, especially in the third aromatic ring, which is free to adopt a bioactive conformation. To resolve these problems, a series of C terminus EM analogues, [Xaa(4)-R]EMs, modified through the substitution of Phe(4) with nonaromatic residues and termination with benzyl groups, were designed to generate conformational constrains of the third aromatic ring by amide bond and torsion angles (phi(4) and psi(4)) of Xaa(4). Introduction of (S)-alpha-methyl or (S)/(R)-alpha-carboxamide on the methylene unit of the benzyl group was designed to produce an atypical topographical constraint (phi(5)) of the third aromatic ring rotation. Interestingly, some EM derivatives, with elimination of the C-terminal carboxamide group and significant changes in the address sequence (Phe(4)-NH(2)), still exhibited higher mu-opioid receptor (MOR) affinity than unmodified EMs. In contrast, some analogues with incorrectly constrained C termini displayed very low affinity and pharmacological activities. Thus, our results indicate that these EM analogues, with atypical constrained C termini, provide model compounds with potent MOR agonism. They also give evidence that the proper spatial orientation and conformational restriction of the third aromatic ring are crucial for the interaction of EMs with MOR.
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Affiliation(s)
- Ye Yu
- Institute of Biochemistry and Molecular Biology, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, 222 Tian Shui South Road, Lanzhou 730000, China
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Wu YC, Hsieh JY, Lin HC, Hwang CC. Conformational stability and three-dimensional model of the δ-opioid pharmacophore for the extended antiparallel dimer structure of Met-enkephalin in water. J Mol Model 2006; 13:171-7. [PMID: 16972066 DOI: 10.1007/s00894-006-0139-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Accepted: 07/04/2006] [Indexed: 12/01/2022]
Abstract
The conformational stability of the extended antiparallel dimer structure of Met-enkephalin in water was analyzed by examining the hydration structure of enkephalin using molecular dynamics simulations. The result shows that, despite of the hydrophicility of the terminal atoms in the pentapeptide, the main contributor for the stability of the dimer in water is the four intermolecular hydrogen bonds between the Gly(2) and Phe(4) groups. The three-dimensional model of the delta-opioid pharmacophore for this dimer structure was also established. Such a model was demonstrated to match the delta-opioid pharmacophore query derived from the non-peptides SIOM, TAN-67, and OMI perfectly. This result thus strongly supports the assumption that the dimer structure of Met-enkephalin is a possible delta-receptor binding conformation.
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Affiliation(s)
- Yng-Ching Wu
- Department of Engineering Science, National Cheng Kung University, Tainan, 701, Taiwan
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Sasaki Y, Kawano S, Kohara H, Watanabe H, Ambo A. ORL1 and opioid receptor preferences of nociceptin and dynorphin A analogues with Dmp substituted for N-terminal aromatic residues. Bioorg Med Chem 2006; 14:2433-7. [PMID: 16321540 DOI: 10.1016/j.bmc.2005.11.021] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Revised: 11/10/2005] [Accepted: 11/11/2005] [Indexed: 11/19/2022]
Abstract
Nociceptin (NOC) and dynorphin A (DYN) analogues containing 2',6'-dimethylphenylalanine (Dmp) in place of Phe or Tyr in position 1 and/or 4 were synthesized and their metabolic stability and receptor-binding properties were investigated. [Dmp1]NOC(1-13)-NH2 (1) possessed high ORL1 receptor affinity comparable to that of the parent peptide with substantially improved affinities for kappa-, mu-, and delta-opioid receptors. However, Dmp4 substitution of NOC peptide (2) reduced ORL1 receptor affinity. [Dmp1]DYN(1-13)-NH2 (4) and its Dmp4 analogue (5) possessed a 3-fold greater kappa-opioid receptor affinity and improved kappa-receptor selectivity compared to the parent peptide. Analogue 4 however exhibited an unexpectedly low in vitro bioactivity (GPI assay), suggesting, the phenolic hydroxyl group at the N-terminal residue in DYN peptide is extremely important for activation of the kappa-opioid receptor. Analogue 5 possessed an improved kappa-opioid receptor selectivity with an IC50 ratio of 1(kappa)/509(mu)/211598(delta); thus, this peptide may serve as a highly selective kappa-receptor agonist for pharmacological study. Dmp1 substitution in both the NOC and DYN peptides improved metabolic stability toward these peptides, while Dmp4 substitution provided no additional metabolic stability.
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Affiliation(s)
- Yusuke Sasaki
- Tohoku Pharmaceutical University, 4-1 Komatsushima 4-chome, Aoba-ku, Sendai 981-8558, Japan.
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Pogozheva ID, Przydzial MJ, Mosberg HI. Homology modeling of opioid receptor-ligand complexes using experimental constraints. AAPS JOURNAL 2005; 7:E434-48. [PMID: 16353922 PMCID: PMC2750980 DOI: 10.1208/aapsj070243] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Opioid receptors interact with a variety of ligands, including endogenous peptides, opiates, and thousands of synthetic compounds with different structural scaffolds. In the absence of experimental structures of opioid receptors, theoretical modeling remains an important tool for structure-function analysis. The combination of experimental studies and modeling approaches allows development of realistic models of ligand-receptor complexes helpful for elucidation of the molecular determinants of ligand affinity and selectivity and for understanding mechanisms of functional agonism or antagonism. In this review we provide a brief critical assessment of the status of such theoretical modeling and describe some common problems and their possible solutions. Currently, there are no reliable theoretical methods to generate the models in a completely automatic fashion. Models of higher accuracy can be produced if homology modeling, based on the rhodopsin X-ray template, is supplemented by experimental structural constraints appropriate for the active or inactive receptor conformations, together with receptor-specific and ligand-specific interactions. The experimental constraints can be derived from mutagenesis and cross-linking studies, correlative replacements of ligand and receptor groups, and incorporation of metal binding sites between residues of receptors or receptors and ligands. This review focuses on the analysis of similarity and differences of the refined homology models of mu, delta, and kappa-opioid receptors in active and inactive states, emphasizing the molecular details of interaction of the receptors with some representative peptide and nonpeptide ligands, underlying the multiple modes of binding of small opiates, and the differences in binding modes of agonists and antagonists, and of peptides and alkaloids.
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Affiliation(s)
- Irina D Pogozheva
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109, USA
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