1
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Fischer NH, Fumi E, Oliveira MT, Thulstrup PW, Diness F. Tuning peptide structure and function through fluorobenzene stapling. Chemistry 2021; 28:e202103788. [PMID: 34897848 DOI: 10.1002/chem.202103788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Indexed: 11/09/2022]
Abstract
Cyclic peptides are promising next-generation therapeutics with improved biological stability and activity. A catalyst-free stapling method for cysteine-containing peptides was developed. This enables fine-tuning of the macrocycle by using the appropriate regioisomers of fluorobenzene linkers. Stapling was performed on the unprotected linear peptide or, more conveniently, directly on-resin after peptide synthesis. NMR spectroscopy and circular dichroism studies demonstrate that the type of stapling can tune the secondary structures of the peptides. The method was applied to a set of potential agonists for melanocortin receptors, generating a library of macrocyclic potent ligands with ortho , meta or para relationships between the thioethers. Their small but significant difference in potency and efficacy demonstrates how the method allows facile fine-tuning of macrocyclic peptides towards biological targets from the same linear precursor.
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Affiliation(s)
| | - Erik Fumi
- University of Copenhagen: Kobenhavns Universitet, Department of Chemistry, DENMARK
| | | | - Peter W Thulstrup
- University of Copenhagen: Kobenhavns Universitet, Department of Chemistry, DENMARK
| | - Frederik Diness
- University of Copenhagen, Department of Chemistry, Universitetsparken 5, DK2100, Copenhagen, DENMARK
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2
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Malik U, Chan LY, Cai M, Hruby VJ, Kaas Q, Daly NL, Craik DJ. Development of novel frog‐skin peptide scaffolds with selectivity towards melanocortin receptor subtypes. Pept Sci (Hoboken) 2020. [DOI: 10.1002/pep2.24209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Uru Malik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science The University of Queensland Brisbane Queensland Australia
| | - Lai Yue Chan
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science The University of Queensland Brisbane Queensland Australia
| | - Minying Cai
- Department of Chemistry and Biochemistry University of Arizona Tucson Arizona USA
| | - Victor J. Hruby
- Department of Chemistry and Biochemistry University of Arizona Tucson Arizona USA
| | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science The University of Queensland Brisbane Queensland Australia
| | - Norelle L. Daly
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science The University of Queensland Brisbane Queensland Australia
- Australian Institute of Tropical Health and Medicine James Cook University Cairns Queensland Australia
| | - David J. Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science The University of Queensland Brisbane Queensland Australia
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3
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Palmer D, Gonçalves JPL, V Hansen L, Wu B, Hald H, Schoffelen S, Diness F, Le Quement ST, Nielsen TE, Meldal M. Click-Chemistry-Mediated Synthesis of Selective Melanocortin Receptor 4 Agonists. J Med Chem 2017; 60:8716-8730. [PMID: 28972753 DOI: 10.1021/acs.jmedchem.7b00353] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The melanocortin receptor 4 (MC4R) subtype of the melanocortin receptor family is a target for therapeutics to ameliorate metabolic dysfunction. Endogenous MC4R agonists possess a critical pharmacophore (HFRW), and cyclization of peptide agonists often enhances potency. Thus, 17 cyclized peptides were synthesized by solid phase click chemistry to develop novel, potent, selective MC4R agonists. Using cAMP measurements and a transcriptional reporter assay, we observed that several constrained agonists generated by a cycloaddition reaction displayed high selectivity (223- to 467-fold) toward MC4R over MC3R and MC5R receptor subtypes without compromising agonist potency. Significant variation was also observed between the EC50 values for the two assays, with robust levels of reporter expression measured at lower concentrations than those effecting appreciable increases in cAMP levels for the majority of the compounds tested. Collectively, we characterized significant elements that modulate the activity of the core pharmacophore for MC4R and provide a rationale for careful assay selection for agonist screening.
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Affiliation(s)
- Daniel Palmer
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Juliana P L Gonçalves
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Louise V Hansen
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Boqian Wu
- Aquaporin A/S , Ole Maaløes Vej 3, 2200 Copenhagen, Denmark
| | - Helle Hald
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Sanne Schoffelen
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Frederik Diness
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
| | | | - Thomas E Nielsen
- Protein & Peptide Chemistry, Novo Nordisk A/S , Novo Nordisk Park, 2760 Måløv, Denmark.,Department of Immunology and Microbiology, University of Copenhagen , Blegdamsvej 3B, 2200 Copenhagen, Denmark.,Singapore Centre on Environmental Life Sciences Engineering, Nanyang Technological University , 60 Nanyang Drive, SG 637551, Singapore
| | - Morten Meldal
- CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark
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4
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Cai M, Marelli UK, Mertz B, Beck JG, Opperer F, Rechenmacher F, Kessler H, Hruby VJ. Structural Insights into Selective Ligand-Receptor Interactions Leading to Receptor Inactivation Utilizing Selective Melanocortin 3 Receptor Antagonists. Biochemistry 2017; 56:4201-4209. [PMID: 28715181 DOI: 10.1021/acs.biochem.7b00407] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Systematic N-methylated derivatives of the melanocortin receptor ligand, SHU9119, lead to multiple binding and functional selectivity toward melanocortin receptors. However, the relationship between N-methylation-induced conformational changes in the peptide backbone and side chains and melanocortin receptor selectivity is still unknown. We conducted comprehensive conformational studies in solution of two selective antagonists of the third isoform of the melanocortin receptor (hMC3R), namely, Ac-Nle-c[Asp-NMe-His6-d-Nal(2')7-NMe-Arg8-Trp9-Lys]-NH2 (15) and Ac-Nle-c[Asp-His6-d-Nal(2')7-NMe-Arg8-NMe-Trp9-NMe-Lys]-NH2 (17). It is known that the pharmacophore (His6-DNal7-Arg8-Trp9) of the SHU-9119 peptides occupies a β II-turn-like region with the turn centered about DNal7-Arg8. The analogues with hMC3R selectivity showed distinct differences in the spatial arrangement of the Trp9 side chains. In addition to our NMR studies, we also carried out molecular-level interaction studies of these two peptides at the homology model of hMC3R. Earlier chimeric human melanocortin 3 receptor studies revealed insights regarding the binding and functional sites of hMC3R selectivity. Upon docking of peptides 15 and 17 to the binding pocket of hMC3R, it was revealed that Arg8 and Trp9 side chains are involved in a majority of the interactions with the receptor. While Arg8 forms polar contacts with D154 and D158 of hMC3R, Trp9 utilizes π-π stacking interactions with F295 and F298, located on the transmembrane domain of hMC3R. It is hypothesized that as the frequency of Trp9-hMC3R interactions decrease, antagonistic activity increases. The absence of any interactions of the N-methyl groups with hMC3R suggests that their primary function is to modulate backbone conformations of the ligands.
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Affiliation(s)
- Minying Cai
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
| | - Udaya Kiran Marelli
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Blake Mertz
- C. Eugene Bennett Department of Chemistry, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Johannes G Beck
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Florian Opperer
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Florian Rechenmacher
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Horst Kessler
- Institute for Advanced Study (IAS) and Center for Integrated Protein Science (CIPSM), Department Chemie, Technische Universität München , 85747 Garching, Germany
| | - Victor J Hruby
- Department of Chemistry and Biochemistry, University of Arizona , Tucson, Arizona 85721, United States
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5
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Cai M, Hruby VJ. The Melanocortin Receptor System: A Target for Multiple Degenerative Diseases. Curr Protein Pept Sci 2016; 17:488-96. [PMID: 26916163 DOI: 10.2174/1389203717666160226145330] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 01/28/2016] [Accepted: 01/08/2016] [Indexed: 01/10/2023]
Abstract
The melanocortin receptor system consists of five closely related G-protein coupled receptors (MC1R, MC2R, MC3R, MC4R and MC5R). These receptors are involved in many of the key biological functions for multicellular animals, including human beings. The natural agonist ligands for these receptors are derived by processing of a primordial animal gene product, proopiomelanocortin (POMC). The ligand for the MC2R is ACTH (Adrenal Corticotropic Hormone), a larger processed peptide from POMC. The natural ligands for the other 4 melanocortin receptors are smaller peptides including α-melanocyte stimulating hormone (α-MSH) and related peptides from POMC (β-MSH and γ-MSH). They all contain the sequence His-Phe-Arg-Trp that is conserved throughout evolution. Thus, there has been considerable difficulty in developing highly selective ligands for the MC1R, MC3R, MC4R and MC5R. In this brief review, we discuss the various approaches that have been taken to design agonist and antagonist analogues and derivatives of the POMC peptides that are selective for the MC1R, MC3R, MC4R and MC5R receptors, via peptide, nonpeptide and peptidomimetic derivatives and analogues and their differential interactions with receptors that may help account for these selectivities.
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Affiliation(s)
| | - Victor J Hruby
- Department of Chemistry & Biochemistry, University of Arizona, 1306 E. University Blvd, Tucson, AZ 85721, USA.
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6
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Testa C, Scrima M, Grimaldi M, D'Ursi AM, Dirain ML, Lubin-Germain N, Singh A, Haskell-Luevano C, Chorev M, Rovero P, Papini AM. 1,4-disubstituted-[1,2,3]triazolyl-containing analogues of MT-II: design, synthesis, conformational analysis, and biological activity. J Med Chem 2014; 57:9424-34. [PMID: 25347033 PMCID: PMC4255721 DOI: 10.1021/jm501027w] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Side chain-to-side chain cyclizations
represent a strategy to select
a family of bioactive conformations by reducing the entropy and enhancing
the stabilization of functional ligand-induced receptor conformations.
This structural manipulation contributes to increased target specificity,
enhanced biological potency, improved pharmacokinetic properties,
increased functional potency, and lowered metabolic susceptibility.
The CuI-catalyzed azide–alkyne 1,3-dipolar Huisgen’s
cycloaddition, the prototypic click reaction, presents a promising
opportunity to develop a new paradigm for an orthogonal bioorganic
and intramolecular side chain-to-side chain cyclization. In fact,
the proteolytic stable 1,4- or 4,1-disubstituted [1,2,3]triazolyl
moiety is isosteric with the peptide bond and can function as a surrogate
of the classical side chain-to-side chain lactam forming bridge. Herein
we report the design, synthesis, conformational analysis, and functional
biological activity of a series of i-to-i+5 1,4- and 4,1-disubstituted
[1,2,3]triazole-bridged cyclopeptides derived from MT-II, the homodetic
Asp5 to Lys10 side chain-to-side chain bridged
heptapeptide, an extensively studied agonist of melanocortin receptors.
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Affiliation(s)
- Chiara Testa
- Laboratoire SOSCO & PeptLab@UCP, EA4505, University of Cergy-Pontoise , 5 mail Gay-Lussac, Neuville sur Oise, F-95031 Cergy-Pontoise Cedex, France
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7
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Ermert P, Moehle K, Obrecht D. Macrocyclic Inhibitors of GPCR's, Integrins and Protein–Protein Interactions. MACROCYCLES IN DRUG DISCOVERY 2014. [DOI: 10.1039/9781782623113-00283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
This chapter summarizes some highlights of macrocyclic drug discovery in the area of GPCRs, integrins, and protein–protein interactions spanning roughly the last 30 years. Several examples demonstrate that incorporation of pharmacophores derived from natural peptide ligands into the context of a constrained macrocycle (“lock of the bioactive conformation”) has proven a powerful approach for the discovery of potent and selective macrocyclic drugs. In addition, it will be shown that macrocycles, due to their semi-rigid nature, can exhibit unique properties that can be beneficially exploited by medicinal chemists. Macrocycles can adapt their conformation during binding to a flexible protein target surface (“induced fit”), and due to their size, can interact with larger protein interfaces (“hot spots”). Also, macrocycles can display favorable ADME properties well beyond the rule of 5 in particular exhibiting favorable cell penetrating properties and oral bioavailability.
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Affiliation(s)
- Philipp Ermert
- Polyphor Ltd Hegenheimermattweg 125 CH-4123 Allschwil Switzerland
| | - Kerstin Moehle
- University of Zurich Winterthurerstrasse 190 CH-8057 Zurich Switzerland
| | - Daniel Obrecht
- Polyphor Ltd Hegenheimermattweg 125 CH-4123 Allschwil Switzerland
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8
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Singh A, Dirain ML, Wilczynski A, Chen C, Gosnell BA, Levine AS, Edison AS, Haskell-Luevano C. Synthesis, biophysical, and pharmacological evaluation of the melanocortin agonist AST3-88: modifications of peptide backbone at Trp 7 position lead to a potent, selective, and stable ligand of the melanocortin 4 receptor (MC4R). ACS Chem Neurosci 2014; 5:1020-31. [PMID: 25141170 PMCID: PMC4198065 DOI: 10.1021/cn5000953] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
![]()
The
melanocortin-3 (MC3R) and melanocortin-4 (MC4R) receptors are
expressed in the brain and are implicated in the regulation of food
intake and energy homeostasis. The endogenous agonist ligands for
these receptors (α-, β-, γ-MSH and ACTH) are linear
peptides with limited receptor subtype selectivity and metabolic stability,
thus minimizing their use as probes to characterize the overlapping
pharmacological and physiological functions of the melanocortin receptor
subtypes. In the present study, an engineered template, in which the
peptide backbone was modified by a heterocyclic reverse turn mimetic
at the Trp7 residue, was synthesized using solid phase
peptide synthesis and characterized by a β-galactosidase cAMP
based reporter gene assay. The functional assay identified a ∼5
nM mouse MC4R agonist (AST3-88) with more than 50-fold selectivity
over the mMC3R. Biophysical studies (2D 1H NMR spectroscopy
and molecular dynamics) of AST3-88 identified a type VIII β-turn
secondary structure spanning the pharmacophore domain stabilized by
the intramolecular interactions between the side chains of the His
and Trp residues. Enzymatic studies of AST3-88 revealed enhanced stability
of AST3-88 over the α-MSH endogenous peptide in rat serum. Upon
central administration of AST3-88 into rats, a decreased food intake
response was observed. This is the first study to probe the in vivo
physiological activity of this engineered peptide-heterocycle template.
These findings advance the present knowledge of pharmacophore design
for potent, selective, and metabolically stable melanocortin ligands.
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Affiliation(s)
- Anamika Singh
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | | | | | | | | | | | | | - Carrie Haskell-Luevano
- Department
of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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9
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Singh A, Dirain M, Witek R, Rocca JR, Edison AS, Haskell-Luevano C. Structure-activity relationships of peptides incorporating a bioactive reverse-turn heterocycle at the melanocortin receptors: identification of a 5800-fold mouse melanocortin-3 receptor (mMC3R) selective antagonist/partial agonist versus the mouse melanocortin-4 receptor (mMC4R). J Med Chem 2013; 56:2747-63. [PMID: 23432160 PMCID: PMC3652311 DOI: 10.1021/jm301253y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The melanocortin-3 (MC3) and melanocortin-4 (MC4) receptors regulate energy homeostasis, food intake, and associated physiological conditions. The melanocortin-4 receptor (MC4R) has been studied extensively. Less is known about specific physiological roles of the melanocortin-3 receptor (MC3R). A major obstacle to this lack of knowledge is attributed to a limited number of identified MC3R selective ligands. We previously reported a spatial scanning approach of a 10-membered thioether-heterocycle ring incorporated into a chimeric peptide template that identified a lead nM MC4R ligand. Upon the basis of those results, 17 compounds were designed and synthesized that focused upon modification in the pharmacophore domain. Notable results include the identification of a 0.13 nM potent 5800-fold mMC3R selective antagonist/slight partial agonist versus a 760 nM mMC4R full agonist (ligand 11). Biophysical experiments (two-dimensional (1)H NMR and computer-assisted molecular modeling) of this ligand resulted in the identification of an inverse γ-turn secondary structure in the ligand pharmacophore domain.
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Affiliation(s)
- Anamika Singh
- Departments of Medicinal Chemistry and Pharmacodynamics University of Florida, Gainesville, FL 32610, USA
- Department of Medicinal Chemistry University of Minnesota, Minneapolis, MN 55455, USA
| | - Marvin Dirain
- Departments of Medicinal Chemistry and Pharmacodynamics University of Florida, Gainesville, FL 32610, USA
| | - Rachel Witek
- Departments of Medicinal Chemistry and Pharmacodynamics University of Florida, Gainesville, FL 32610, USA
| | - James R. Rocca
- McKnight Brain Institute, University of Florida, Gainesville, FL 32611
| | - Arthur S Edison
- Department of Biochemistry & Molecular Biology and National High Magnetic Field Laboratory, University of Florida, Gainesville, FL 32610, USA
| | - Carrie Haskell-Luevano
- Departments of Medicinal Chemistry and Pharmacodynamics University of Florida, Gainesville, FL 32610, USA
- Department of Medicinal Chemistry University of Minnesota, Minneapolis, MN 55455, USA
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10
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Cai M, Stankova M, Muthu D, Mayorov A, Yang Z, Trivedi D, Cabello C, Hruby VJ. An unusual conformation of γ-melanocyte-stimulating hormone analogues leads to a selective human melanocortin 1 receptor antagonist for targeting melanoma cells. Biochemistry 2013; 52:752-64. [PMID: 23276279 PMCID: PMC3641192 DOI: 10.1021/bi300723f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
γ-MSH (γ-melanocyte-stimulating hormone, H-Tyr-Val-Met-Gly-His-Phe-Arg-Trp-Asp-Arg-Phe-Gly-OH), with its exquisite specificity and potency, has recently created much excitement as a drug lead. However, this peptide is like most peptides susceptible to proteolysis in vivo, which potentially decreases its beneficial activities. In our continued effort to design a proteolytically stable ligand with specific receptor binding, we have engineered peptides by cyclizing γ-MSH using a thioether bridge. A number of novel cyclic truncated γ-MSH analogues were designed and synthesized, in which a thioether bridge was incorporated between a cysteine side chain and an N-terminal bromoacyl group. One of these peptides, cyclo-[(CH(2))(3)CO-Gly(1)-His(2)-D-Phe(3)-Arg(4)-D-Trp(5)-Cys(S-)(6)]-Asp(7)-Arg(8)-Phe(9)-Gly(10)-NH(2), demonstrated potent antagonist activity and receptor selectivity for the human melanocortin 1 receptor (hMC1R) (IC(50) = 17 nM). This novel peptide is the most selective antagonist for the hMC1R to date. Further pharmacological studies have shown that this peptide can specifically target melanoma cells. The nuclear magnetic resonance analysis of this peptide in a membrane-like environment revealed a new turn structure, specific to the hMC1R antagonist, at the C-terminus, where the side chain and backbone conformation of D-Trp(5) and Phe(9) of the peptide contribute to hMC1R selectivity. Cyclization strategies represent an approach for stabilizing bioactive peptides while keeping their full potencies and should boost applications of peptide-based drugs in human medicine.
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Affiliation(s)
- Minying Cai
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
| | | | - Dhanasekaran Muthu
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
| | - Alexander Mayorov
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
| | - Zhehui Yang
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
| | - Devendra Trivedi
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
| | - Christopher Cabello
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
| | - Victor J. Hruby
- Department of Chemistry and Biochemistry, 1306 E. University Blvd., University of Arizona, Tucson, Arizona 85721
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11
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Morais M, Raposinho PD, Oliveira MC, Pantoja-Uceda D, Jiménez MA, Santos I, Correia JDG. NMR Structural Analysis of MC1R-Targeted Rhenium(I) Metallopeptides and Biological Evaluation of 99mTc(I) Congeners. Organometallics 2012. [DOI: 10.1021/om300502n] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Maurício Morais
- Unidade de Ciências Quı́micas
e Radiofarmacêuticas, ITN, Instituto Superior
Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953, Sacavém, Portugal
| | - Paula D. Raposinho
- Unidade de Ciências Quı́micas
e Radiofarmacêuticas, ITN, Instituto Superior
Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953, Sacavém, Portugal
| | - Maria Cristina Oliveira
- Unidade de Ciências Quı́micas
e Radiofarmacêuticas, ITN, Instituto Superior
Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953, Sacavém, Portugal
| | - David Pantoja-Uceda
- Instituto de Quı́mica Fı́sica Rocasolano, Consejo Superior de Investigaciones Científicas (CSIC), Serrano 119, 28006 Madrid, Spain
| | - Maria Angeles Jiménez
- Instituto de Quı́mica Fı́sica Rocasolano, Consejo Superior de Investigaciones Científicas (CSIC), Serrano 119, 28006 Madrid, Spain
| | - Isabel Santos
- Unidade de Ciências Quı́micas
e Radiofarmacêuticas, ITN, Instituto Superior
Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953, Sacavém, Portugal
| | - João D. G. Correia
- Unidade de Ciências Quı́micas
e Radiofarmacêuticas, ITN, Instituto Superior
Técnico, Universidade Técnica de Lisboa, Estrada Nacional 10, 2686-953, Sacavém, Portugal
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12
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Hruby VJ, Cai M, Cain J, Nyberg J, Trivedi D. Design of novel melanocortin receptor ligands: multiple receptors, complex pharmacology, the challenge. Eur J Pharmacol 2011; 660:88-93. [PMID: 21208601 PMCID: PMC3138524 DOI: 10.1016/j.ejphar.2010.10.109] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Revised: 10/05/2010] [Accepted: 10/16/2010] [Indexed: 11/22/2022]
Abstract
The major pharmacophore for the melanocortin 1, 3, 4 and 5 receptors is the sequence -His-Phe-Arg-Trp-. There is a need for potent, biologically stable, receptor selective ligands, both agonists and antagonists, for these receptors. In this report we briefly examine the structural and biophysical approaches we have taken to develop selective agonist and antagonist ligands that can cross (or not) the blood brain barrier. Remaining questions and unmet needs are also discussed.
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Affiliation(s)
- Victor J Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA.
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13
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Grieco P, Brancaccio D, Novellino E, Hruby VJ, Carotenuto A. Conformational study on cyclic melanocortin ligands and new insight into their binding mode at the MC4 receptor. Eur J Med Chem 2011; 46:3721-33. [PMID: 21652123 DOI: 10.1016/j.ejmech.2011.05.038] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 05/12/2011] [Accepted: 05/14/2011] [Indexed: 11/30/2022]
Abstract
The melanocortin receptors are involved in many physiological functions, including pigmentation, sexual function, feeding behavior, and energy homeostasis, making them potential targets to treat obesity, sexual dysfunction, etc. Understanding the basis of the ligand-receptor interactions is crucial for the design of potent and selective ligands for these receptors. The conformational preferences of the cyclic melanocortin ligands MTII (Ac-Nle(4)-c[Asp(5)-His(6)-DPhe(7)-Arg(8)-Trp(9)-Lys(10)]-NH(2)) and SHU9119 (Ac-Nle(4)-c[Asp(5)-His(6)-DNal(2')(7)-Arg(8)-Trp(9)-Lys(10)]-NH(2)), which show agonist and antagonist activity at the h-MC4R, respectively, were comprehensively investigated by solution NMR spectroscopy in different environments. In particular, water and water/DMSO (8:2) solutions were used as isotropic solutions and an aqueous solution of DPC (dodecylphosphocholine) micelles was used as a membrane mimetic environment. NMR-derived conformations of these two ligands were docked within h-MC4R models. NMR and docking studies revealed intriguing differences which can help explain the different activities of these two ligands.
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Affiliation(s)
- Paolo Grieco
- Department of Pharmaceutical and Toxicological Chemistry, University of Naples Federico II, I-80131 Naples, Italy
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14
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Mayorov AV, Cai M, Palmer ES, Tanaka DK, Cain JP, Dedek MM, Tan B, Trivedi D, Hruby VJ. Cyclic lactam hybrid α-MSH/Agouti-related protein (AGRP) analogues with nanomolar range binding affinities at the human melanocortin receptors. Bioorg Med Chem Lett 2011; 21:3099-102. [PMID: 21486697 DOI: 10.1016/j.bmcl.2011.03.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Revised: 03/04/2011] [Accepted: 03/07/2011] [Indexed: 11/30/2022]
Abstract
A novel hybrid melanocortin pharmacophore was designed based on the topographical similarities between the pharmacophores of Agouti related protein (AGRP) an endogenous melanocortin antagonist, and α-melanocyte-stimulating hormone (α-MSH), an endogenous melanocortin agonist. When employed in two different 23-membered macrocyclic lactam peptide templates, the designed hybrid AGRP/MSH pharmacophore yielded non-competitive ligands with nanomolar range binding affinities. The topography-based pharmacophore hybridization strategy will prove useful in development of unique non-competitive melanocortin receptor modulators.
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Affiliation(s)
- Alexander V Mayorov
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
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15
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Lee CJ, Yun JH, Lim SK, Lee W. Solution structures and molecular interactions of selective melanocortin receptor antagonists. Mol Cells 2010; 30:551-6. [PMID: 21110130 DOI: 10.1007/s10059-010-0152-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 09/11/2010] [Accepted: 09/13/2010] [Indexed: 10/18/2022] Open
Abstract
The solution structures and inter-molecular interaction of the cyclic melanocortin antagonists SHU9119, JKC363, HS014, and HS024 with receptor molecules have been determined by NMR spectroscopy and molecular modeling. While SHU9119 is known as a nonselective antagonist, JKC363, HS014, and HS024 are selective for the melanocortin subtype-4 receptor (MC4R) involved in modulation of food intake. Data from NMR and molecular dynamics suggest that the conformation of the Trp9 sidechain in the three MC4R-selective antagonists is quite different from that of SHU9119. This result strongly supports the concept that the spatial orientation of the hydrophobic aromatic residue is more important for determining selectivity than the presence of a basic, "arginine-like" moiety responsible for biological activity. We propose that the conformation of hydrophobic residues of MCR antagonists is critical for receptor-specific selectivity.
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MESH Headings
- Amino Acid Sequence
- Binding Sites
- Drug Interactions
- Hydrophobic and Hydrophilic Interactions
- Magnetic Resonance Spectroscopy
- Melanocyte-Stimulating Hormones/chemical synthesis
- Melanocyte-Stimulating Hormones/chemistry
- Melanocyte-Stimulating Hormones/pharmacology
- Models, Molecular
- Molecular Sequence Data
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/pharmacology
- Receptor, Melanocortin, Type 4/antagonists & inhibitors
- Receptor, Melanocortin, Type 4/drug effects
- Receptors, Melanocortin/antagonists & inhibitors
- Receptors, Melanocortin/drug effects
- Sensitivity and Specificity
- Solutions/chemistry
- Structure-Activity Relationship
- beta-MSH/chemical synthesis
- beta-MSH/chemistry
- beta-MSH/pharmacology
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Affiliation(s)
- Chul-Jin Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, Korea
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16
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Mayorov AV, Cai M, Palmer ES, Liu Z, Cain JP, Vagner J, Trivedi D, Hruby VJ. Solid-phase peptide head-to-side chain cyclodimerization: discovery of C(2)-symmetric cyclic lactam hybrid α-melanocyte-stimulating hormone (MSH)/agouti-signaling protein (ASIP) analogues with potent activities at the human melanocortin receptors. Peptides 2010; 31:1894-905. [PMID: 20688117 PMCID: PMC3041174 DOI: 10.1016/j.peptides.2010.06.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2010] [Revised: 06/23/2010] [Accepted: 06/23/2010] [Indexed: 02/05/2023]
Abstract
A novel hybrid melanocortin pharmacophore was designed based on the pharmacophores of the agouti-signaling protein (ASIP), an endogenous melanocortin antagonist, and α-melanocyte-stimulating hormone (α-MSH), an endogenous melanocortin agonist. The designed hybrid ASIP/MSH pharmacophore was explored in monomeric cyclic, and cyclodimeric templates. The monomeric cyclic disulfide series yielded peptides with hMC3R-selective non-competitive binding affinities. The direct on-resin peptide lactam cyclodimerization yielded nanomolar range (25-120 nM) hMC1R-selective full and partial agonists in the cyclodimeric lactam series which demonstrates an improvement over the previous attempts at hybridization of MSH and agouti protein sequences. The secondary structure-oriented pharmacophore hybridization strategy will prove useful in development of unique allosteric and orthosteric melanocortin receptor modulators. This report also illustrates the utility of peptide cyclodimerization for the development of novel GPCR peptide ligands.
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Affiliation(s)
| | - Minying Cai
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
| | - Erin S. Palmer
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
| | - Zhihua Liu
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
| | - James P. Cain
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
| | - Josef Vagner
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
| | - Dev Trivedi
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
| | - Victor J. Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, USA
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17
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Interactions of the melanocortin-4 receptor with the peptide agonist NDP-MSH. J Mol Biol 2010; 401:433-50. [PMID: 20600126 PMCID: PMC3101337 DOI: 10.1016/j.jmb.2010.06.028] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Revised: 06/14/2010] [Accepted: 06/15/2010] [Indexed: 02/05/2023]
Abstract
Melanocortin-4 receptor (MC4R) has an important regulatory role in energy homeostasis and food intake. Peptide agonists of the MC4R are characterized by the conserved sequence His6-Phe7-Arg8-Trp9, which is crucial for their interaction with the receptor. This investigation utilized the covalent attachment approach to identify receptor residues in close proximity to the bound ligand [Nle4,d-Phe7]melanocyte-stimulating hormone (NDP-MSH), thereby differentiating between residues directly involved in ligand binding and those mutations that compromise ligand binding by inducing conformational changes in the receptor. Also, recent X-ray structures of G-protein-coupled receptors were utilized to refine a model of human MC4R in the active state (R⁎), which was used to generate a better understanding of the binding mode of the ligand NDP-MSH at the atomic level. The mutation of residues in the human MC4R—such as Leu106 of extracellular loop 1, and Asp122, Ile125, and Asp126 of transmembrane (TM) helix 3, His264 (TM6), and Met292 (TM7)—to Cys residues produced definitive indications of proximity to the side chains of residues in the core region of the peptide ligand. Of particular interest was the contact between d-Phe7 on the ligand and Ile125 of TM3 on the MC4R. Additionally, Met292 (TM7) equivalent to Lys(7.45) (Ballesteros numbering scheme) involved in covalently attaching retinal in rhodopsin is shown to be in close proximity to Trp9. For the first time, the interactions between the terminal regions of NDP-MSH and the receptor are described. The amino-terminus appears to be adjacent to a series of hydrophilic residues with novel interactions at Cys196 (TM5) and Asp189 (extracellular loop 2). These interactions are reminiscent of sequential ligand binding exhibited by the β2-adrenergic receptor, with the former interaction being equivalent to the known interaction involving Ser204 of the β2-adrenergic receptor.
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18
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Doedens L, Opperer F, Cai M, Beck JG, Dedek M, Palmer E, Hruby VJ, Kessler H. Multiple N-methylation of MT-II backbone amide bonds leads to melanocortin receptor subtype hMC1R selectivity: pharmacological and conformational studies. J Am Chem Soc 2010; 132:8115-28. [PMID: 20496895 PMCID: PMC2895553 DOI: 10.1021/ja101428m] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Multiple N-methylation is a novel technology to improve bioavailability of peptides and increase receptor subtype selectivity. This technique has been applied here to the superpotent but nonselective cyclic peptide MT-II. A library of all possible 31 backbone N-methylated derivatives has been synthesized and tested for binding and activation at melanocortin receptor subtypes 1, 3, 4, and 5. It turned out that selectivity is improved with every introduced N-methyl group, resulting in several N-methylated selective and potent agonists for the hMC1R. The most potent of these derivatives is N-methylated on four out of five amide bonds in the cyclic structure. Its solution structure indicates a strongly preferred backbone conformation that resembles other alpha-MSH analogs but possesses much less flexibility and in addition distinct differences in the spatial arrangement of individual amino acid side chains.
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Affiliation(s)
- Lucas Doedens
- Institute for Advanced Study and Center for Integrated Protein Science at the Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Florian Opperer
- Institute for Advanced Study and Center for Integrated Protein Science at the Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Minying Cai
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, 85721, U.S.A
| | - Johannes G. Beck
- Institute for Advanced Study and Center for Integrated Protein Science at the Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
| | - Matt Dedek
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, 85721, U.S.A
| | - Erin Palmer
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, 85721, U.S.A
| | - Victor J. Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona, 85721, U.S.A
| | - Horst Kessler
- Institute for Advanced Study and Center for Integrated Protein Science at the Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany
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19
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Lee YS, Fernandes S, Kulkarani V, Mayorov A, Davis P, Ma SW, Brown K, Gillies RJ, Lai J, Porreca F, Hruby VJ. Design and synthesis of trivalent ligands targeting opioid, cholecystokinin, and melanocortin receptors for the treatment of pain. Bioorg Med Chem Lett 2010; 20:4080-4. [PMID: 20547453 DOI: 10.1016/j.bmcl.2010.05.078] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 05/18/2010] [Accepted: 05/19/2010] [Indexed: 11/29/2022]
Abstract
It has been known that co-administration of morphine with either cholecystokinin (CCK) receptor or melanocortin (MC) receptor antagonists enhance morphine's analgesic efficacy by reducing serious side effects such as tolerance and addiction. Considering these synergistic effects, we have designed trivalent ligands in which all three different pharmacophores for opioid, CCK, and MC receptors are combined in such a way as to conserve their own topographical pharmacophore structures. These ligands, excluding the cyclic compound, were synthesized by solid phase synthesis using Rink-amide resin under microwave assistance in very high yields. These trivalent ligands bind to their respective receptors well demonstrating that the topographical pharmacophore structures for the three receptors were retained for receptor binding. Ligand 10 was a lead compound to show the best biological activities at all three receptors.
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Affiliation(s)
- Yeon Sun Lee
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ 85721, USA
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20
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Abstract
From a scientific perspective, efforts to understand biology including what constitutes health and disease has become a chemical problem. However, chemists and biologists "see" the problems of understanding biology from different perspectives, and this has retarded progress in solving the problems especially as they relate to health and disease. This suggests that close collaboration between chemists and biologists is not only necessary but essential for progress in both the biology and chemistry that will provide solutions to the global questions of biology. This perspective has directed my scientific efforts for the past 45 years, and in this overview I provide my perspective of how the applications of synthetic chemistry, structural design, and numerous other chemical principles have intersected in my collaborations with biologists to provide new tools, new science, and new insights that were only made possible and fruitful by these collaborations.
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Affiliation(s)
- Victor J Hruby
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona 85721, USA.
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21
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Qu H, Cai M, Mayorov AV, Grieco P, Zingsheim M, Trivedi D, Hruby VJ. Substitution of arginine with proline and proline derivatives in melanocyte-stimulating hormones leads to selectivity for human melanocortin 4 receptor. J Med Chem 2009; 52:3627-35. [PMID: 19473029 DOI: 10.1021/jm801300c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new series of melanotropin analogues with His or Arg residues in the core pharmacophores of MTII, SHU9119, and Ac-NDP-gamma-MSH-NH(2) replaced by Pro or trans-/cis-4-guanidinyl-Pro derivatives were designed and synthesized to introduce selectivity toward the human melanocortin 4 receptor (hMC4R). Analogues 1, 2, 3, 6, 7, 8 were found to be hMC4R selective. Second messenger studies have demonstrated that analogues 1 and 2 are insurmountable inhibitors of MTII agonist activity at the hMC4R. Molecular modeling studies suggest that the hMC4R selectivity is due to a beta-turn shift induced by the Pro ring that makes the global minimum structures of these analogues resemble the NMR solution structure of the hASIP melanocortin receptor binding motif. Substitution of His in MTII also provided functional selectivity for the hMC3R or the hMC4R. These findings are important for a better understanding of the selectivity mechanism at the hMC3R/hMC4R and the development of therapeutic ligands selectively targeting the hMC4R.
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Affiliation(s)
- Hongchang Qu
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA
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22
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Haslach EM, Schaub JW, Haskell-Luevano C. Beta-turn secondary structure and melanocortin ligands. Bioorg Med Chem 2009; 17:952-8. [PMID: 18343128 PMCID: PMC2662475 DOI: 10.1016/j.bmc.2008.02.090] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Revised: 02/26/2008] [Accepted: 02/27/2008] [Indexed: 10/22/2022]
Abstract
The melanocortin pathway has emerged during this past decade as an important target area for the discovery and development of therapeutic agents related to obesity and type 2 diabetes. This peptide-G-protein coupled receptor (GPCR) pathway has evolved from peptide-based ligands to small molecules possessing a variety of different molecular scaffolds. Herein, we summarize the originating hypothesis of the importance of the reverse beta-turn secondary structure for agonist ligand potency at the melanocortin receptors and how that information was utilized for the discovery of small molecules based upon this type of turn structure.
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Affiliation(s)
- Erica M. Haslach
- Department of Medicinal Chemistry, University of Florida PO Box 100485, Gainesville, FL 32610
| | - Jay W. Schaub
- Department of Medicinal Chemistry, University of Florida PO Box 100485, Gainesville, FL 32610
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry, University of Florida PO Box 100485, Gainesville, FL 32610
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23
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Design And Parallel Synthesis Of New Bicyclic Small Molecules For Targeting The Melanocortin Receptors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 611:187-8. [DOI: 10.1007/978-0-387-73657-0_86] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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24
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Verdié P, Subra G, Averland-Petit MC, Amblard M, Martinez J. Solid-Phase Synthesis of 4-Methylcarboxy-1,4-benzodiazepine-2,5-diones. ACTA ACUST UNITED AC 2008; 10:869-74. [DOI: 10.1021/cc800085d] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Pascal Verdié
- Institut des Biomolécules Max Mousseron (IBMM) UMR 5247 CNRS, Universités Montpellier 1 et 2, Faculté de Pharmacie, 15 Avenue Charles Flahault BP 14491, 34093 Montpellier Cedex 5, France, and Laboratoire de Chimie-Physique Macromoléculaire UMR 7568 CNRS, Université Nancy, 1 rue Grandville, B.P. 20451, 54001 Nancy Cedex 1, France
| | - Gilles Subra
- Institut des Biomolécules Max Mousseron (IBMM) UMR 5247 CNRS, Universités Montpellier 1 et 2, Faculté de Pharmacie, 15 Avenue Charles Flahault BP 14491, 34093 Montpellier Cedex 5, France, and Laboratoire de Chimie-Physique Macromoléculaire UMR 7568 CNRS, Université Nancy, 1 rue Grandville, B.P. 20451, 54001 Nancy Cedex 1, France
| | - Marie-Christine Averland-Petit
- Institut des Biomolécules Max Mousseron (IBMM) UMR 5247 CNRS, Universités Montpellier 1 et 2, Faculté de Pharmacie, 15 Avenue Charles Flahault BP 14491, 34093 Montpellier Cedex 5, France, and Laboratoire de Chimie-Physique Macromoléculaire UMR 7568 CNRS, Université Nancy, 1 rue Grandville, B.P. 20451, 54001 Nancy Cedex 1, France
| | - Muriel Amblard
- Institut des Biomolécules Max Mousseron (IBMM) UMR 5247 CNRS, Universités Montpellier 1 et 2, Faculté de Pharmacie, 15 Avenue Charles Flahault BP 14491, 34093 Montpellier Cedex 5, France, and Laboratoire de Chimie-Physique Macromoléculaire UMR 7568 CNRS, Université Nancy, 1 rue Grandville, B.P. 20451, 54001 Nancy Cedex 1, France
| | - Jean Martinez
- Institut des Biomolécules Max Mousseron (IBMM) UMR 5247 CNRS, Universités Montpellier 1 et 2, Faculté de Pharmacie, 15 Avenue Charles Flahault BP 14491, 34093 Montpellier Cedex 5, France, and Laboratoire de Chimie-Physique Macromoléculaire UMR 7568 CNRS, Université Nancy, 1 rue Grandville, B.P. 20451, 54001 Nancy Cedex 1, France
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25
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Grieco P, Cai M, Liu L, Mayorov A, Chandler K, Trivedi D, Lin G, Campiglia P, Novellino E, Hruby VJ. Design and microwave-assisted synthesis of novel macrocyclic peptides active at melanocortin receptors: discovery of potent and selective hMC5R receptor antagonists. J Med Chem 2008; 51:2701-7. [PMID: 18412316 DOI: 10.1021/jm701181n] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Differentiation of the physiological role of the melanocortin receptor 5 MC5R from that of other melanocortin receptors will require development of high affinity and selective antagonists. To date, a few synthetic antagonist ligands active at hMC5 receptor are available, but most do not have appreciable selectivity. With the aim to gain more potent and selective antagonists for the MC5R ligands, we have designed, synthesized, and pharmacologically characterized a series of alkylthioaryl-bridged macrocyclic peptide analogues derived from MT-II and SHU9119. These 20-membered macrocycles were synthesized by a tandem combination using solid phase peptide synthesis and microwave-assisted reactions. Biological assays for binding affinities and adenylate cyclase activities for the hMC1R, hMC3R, hMC4R, and hMC5R showed that three analogues, compounds, 9, 4, and 7, are selective antagonists at the hMC5 receptor. In particular, compound 9(PG-20N) is a selective and competitive hMC5R antagonist, with IC 50 of 130 +/- 11 nM, and a pA 2 value of 8.3, and represents an important tool for further biological investigations of the hMC5R. Compounds 4 and 7 (PG14N, PG17N) show potent and selective allosteric inhibition at hMC5R with IC 50 values of 38 +/- 3 nM and 58 +/- 6 nM, respectively. Compound 9 will be used to further investigate and more clearly understand the physiological roles played by the MC5 receptor in humans and other animals.
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Affiliation(s)
- Paolo Grieco
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA
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26
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Mayorov AV, Cai M, Palmer ES, Dedek MM, Cain JP, Van Scoy AR, Tan B, Vagner J, Trivedi D, Hruby VJ. Structure-activity relationships of cyclic lactam analogues of alpha-melanocyte-stimulating hormone (alpha-MSH) targeting the human melanocortin-3 receptor. J Med Chem 2008; 51:187-95. [PMID: 18088090 PMCID: PMC2587288 DOI: 10.1021/jm070461w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A variety of dicarboxylic acid linkers introduced between the alpha-amino group of Pro(6) and the -amino group of Lys(10) of the cyclic lactam alpha-melanocyte-stimulating hormone (alpha-MSH)-derived Pro(6)-D-Phe(7)/D-Nal(2')(7)-Arg(8)-Trp(9)-Lys(10)-NH2 pentapeptide template lead to nanomolar range and selective hMC3R agonists and antagonists. Replacement of the Pro(6) residue and the dicarboxylic acid linker with 2,3-pyrazine-dicarboxylic acid furnished a highly selective nanomolar range hMC3R partial agonist (analogue 12, c[CO-2,3-pyrazine-CO-D-Phe-Arg-Trp-Lys]-NH2, EC50 = 27 nM, 70% max cAMP) and an hMC3R antagonist (analogue 13, c[CO-2,3-pyrazine-CO-D-Nal(2')-Arg-Trp-Lys]-NH2, IC50 = 23 nM). Modeling experiments suggest that 2,3-pyrazinedicarboxylic acid stabilizes a beta-turn-like structure with the D-Phe/D-Nal(2') residues, which explains the high potency of the corresponding peptides. Placement of a Nle residue in position 6 produced a hMC3R/hMC5R antagonist (analogue 15, c[CO-(CH 2)2-CO-Nle-D-Nal(2')-Arg-Trp-Lys]-NH2, IC50 = 12 and 17 nM, respectively), similarly to the previously described cyclic gamma-melanocyte-stimulating hormone (gamma-MSH)-derived hMC3R/hMC5R antagonists. These newly developed melanotropins will serve as critical biochemical tools for elucidating the full spectrum of functions performed by the physiologically important melanocortin-3 receptor.
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MESH Headings
- Binding, Competitive
- Cell Line
- Cyclic AMP/biosynthesis
- Humans
- Lactams/chemical synthesis
- Lactams/pharmacology
- Models, Molecular
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/pharmacology
- Radioligand Assay
- Receptor, Melanocortin, Type 3/agonists
- Receptor, Melanocortin, Type 3/antagonists & inhibitors
- Receptor, Melanocortin, Type 3/chemistry
- Structure-Activity Relationship
- alpha-MSH/analogs & derivatives
- alpha-MSH/chemical synthesis
- alpha-MSH/pharmacology
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Affiliation(s)
| | - Minying Cai
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Erin S. Palmer
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Matthew M. Dedek
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - James P. Cain
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - April R. Van Scoy
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Bahar Tan
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Josef Vagner
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Dev Trivedi
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Victor J. Hruby
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
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27
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Carotenuto A, Saviello MR, Auriemma L, Campiglia P, Catania A, Novellino E, Grieco P. Structure-function relationships and conformational properties of alpha-MSH(6-13) analogues with candidacidal activity. Chem Biol Drug Des 2007; 69:68-74. [PMID: 17313459 DOI: 10.1111/j.1747-0285.2007.00473.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alpha-melanocyte-stimulating hormone (alpha-MSH) is an endogenous linear tridecapeptide with potent anti-inflammatory effects. We firstly demonstrated that alpha-MSH and its C-terminal sequence Lys-Pro-Val [alpha-MSH(11-13)] have antimicrobial effects against two major and representative pathogens: Staphylococcus aureus and Candida albicans. Successively, in an attempt to improve the candidacidal activity of alpha-MSH and to better understand the peptide structure-antifungal activity relations, we have recently designed and synthesized novel peptide analogues. We focused on the sequence alpha-MSH(6-13), which contains the invariant melanocortin core sequence His-Phe-Arg-Trp (6-9) and also contains the sequence Lys-Pro-Val (11-13) important for antimicrobial activity. In that structure-activity study, we discovered several compounds that have greater candidacidal activity than alpha-MSH, among which the peptide [d-Nal-7,Phe-12]-alpha-MSH(6-13) was the most potent. Here, we report a detailed conformational analysis by spectroscopic and computational methods of three peptides, alpha-MSH(6-13) (1), [d-Nal-7,Phe-12]-alpha-MSH(6-13) (2) and [d-Nal-7,Asp-12]-alpha-MSH(6-13) (3). Peptides were chosen on the basis of their candidacidal activities and were studied in membrane mimetic environment (SDS micelles). Different turn structures were observed for the three peptides and a conformation-activity model was developed based on these results. This study offers a structural basis for the design of novel peptide and non-peptide analogues to be used as new antimicrobial agents.
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Affiliation(s)
- Alfonso Carotenuto
- Department of Pharmaceutical and Toxicological Chemistry, University of Naples Federico II, Via D. Montesano 49, I-80131 Naples, Italy
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28
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Ballet S, Mayorov AV, Cai M, Tymecka D, Chandler KB, Palmer ES, Rompaey KV, Misicka A, Tourwé D, Hruby VJ. Novel selective human melanocortin-3 receptor ligands: use of the 4-amino-1,2,4,5-tetrahydro-2-benzazepin-3-one (Aba) scaffold. Bioorg Med Chem Lett 2007; 17:2492-8. [PMID: 17314042 PMCID: PMC2442462 DOI: 10.1016/j.bmcl.2007.02.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2007] [Revised: 02/06/2007] [Accepted: 02/07/2007] [Indexed: 11/20/2022]
Abstract
In search of new selective antagonists and/or agonists for the human melanocortin receptor subtypes hMC1R to hMC5R to elucidate the specific biological roles of each GPCR, we modified the structures of the superagonist MT-II (Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH(2)) and the hMC3R/hMC4R antagonist SHU9119 (Ac-Nle-c[Asp-His-D-Nal(2')-Arg-Trp-Lys]-NH(2)) by replacing the His-d-Phe and His-d-Nal(2') fragments in MT-II and SHU9119, respectively, with Aba-Xxx (4-amino-1,2,4,5-tetrahydro-2-benzazepin-3-one-Xxx) dipeptidomimetics (Xxx=D-Phe/pCl-D-Phe/D-Nal(2')). Employment of the Aba mimetic yielded novel selective high affinity hMC3R and hMC3R/hMC5R antagonists.
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Affiliation(s)
- Steven Ballet
- Department of Organic Chemistry, Vrije Universiteit Brussel, B-1050 Brussels, Belgium.
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29
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Ying J, Gu X, Cai M, Dedek M, Vagner J, Trivedi DB, Hruby VJ. Design, synthesis, and biological evaluation of new cyclic melanotropin peptide analogues selective for the human melanocortin-4 receptor. J Med Chem 2007; 49:6888-96. [PMID: 17154518 PMCID: PMC1764620 DOI: 10.1021/jm060768f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intensive efforts have been made to develop potent and selective ligands for certain human melanocortin receptors as possible treatments for obesity and sexual dysfunction due to the role of these receptors in feeding behavior, energy homeostasis, sexual function, etc. A number of novel alpha-MSH analogues were designed and synthesized primarily on the basis of our previous MTII NMR structure. In these peptide analogues, a disulfide or lactam bridge between residues at positions 5 and 8 was used as a conformational constraint to enhance the beta-turn spanning His6 and D-Phe7, while the pharmacophore group in Arg8 was mimicked via Nalpha-alkylation of residues 8 or 9 with the guanidinylbutyl group. Biological assays for binding affinities and adenylate cyclase activities for the hMC1R, hMC3R, hMC4R, and hMC5R showed that three analogues have good binding affinity for the hMC4R (0.7-4.1 nM), but have no binding affinity up to 10 microM at the other three melanocortin receptors. Interestingly, the three hMC4R selective analogues display only 50% binding efficiency, suggesting there is allosteric modulation of the melanocortin-4 receptor. These analogues were found to act as antagonists of the hMC4R. This result represents a discovery of very selective peptide-based antagonists for the hMC4R. The high selectivity may be due to the strong conformational constraint via ring contraction as compared to MTII, and the rigid conformation preferred by these new ligands allows them to recognize only the hMC4R, but not to activate the second messenger. The MTII NMR structure-based design thus not only examined the structural model of melanocortin ligands, but also yielded new biologically unique alpha-MSH analogues.
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MESH Headings
- Adenylyl Cyclases/metabolism
- Allosteric Regulation
- Binding, Competitive
- Cell Line
- Drug Design
- Humans
- Ligands
- Magnetic Resonance Spectroscopy
- Molecular Conformation
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/pharmacology
- Protein Structure, Secondary
- Radioligand Assay
- Receptor, Melanocortin, Type 4/agonists
- Receptor, Melanocortin, Type 4/antagonists & inhibitors
- Receptor, Melanocortin, Type 4/metabolism
- Structure-Activity Relationship
- alpha-MSH/analogs & derivatives
- alpha-MSH/chemical synthesis
- alpha-MSH/chemistry
- alpha-MSH/pharmacology
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Affiliation(s)
- Jinfa Ying
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA
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30
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Hruby VJ, Cai M, Cain JP, Mayorov AV, Dedek MM, Trivedi D. Design, synthesis and biological evaluation of ligands selective for the melanocortin-3 receptor. Curr Top Med Chem 2007; 7:1107-19. [PMID: 17584128 PMCID: PMC2274922 DOI: 10.2174/156802607780906645] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The processed products of the proopiomelanocortin gene (ACTH, alpha-MSH, beta-MSH, gamma-MSH, etc.) interact with five melanocortin receptors, the MC1R, MC2R, MC3R, MC4R, and MC5R to modulate and control many important biological functions crucial for good health both peripherally (as hormones) and centrally (as neurotransmitters). Pivotal biological functions include pigmentation, adrenal function, response to stress, fear/flight, energy homeostasis, feeding behavior, sexual function and motivation, pain, immune response, and many others, and are believed to be involved in many disease states including pigmentary disorders, adrenal disorders, obesity, anorexia, prolonged and neuropathic pain, inflammatory response, etc. The melanocortin-3 receptor (MC3R) is found primarily in the brain and spinal cord and also in the periphery, and its biological functions are still not well understood. Here we review some of the biological functions attributed to the MC3R, and then examine in more detail efforts to design and synthesize ligands that are potent and selective for the MC3R, which might help resolve the many questions still remaining about its function. Though some progress has been made, there is still much to be done in this critical area.
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Affiliation(s)
- Victor J Hruby
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA.
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31
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Verdié P, Subra G, Feliu L, Sanchez P, Bergé G, Garcin G, Martinez J. On-Line Synthesis of Pseudopeptide Library Incorporating a Benzodiazepinone Turn Mimic: Biological Evaluation on MC1 Receptors. ACTA ACUST UNITED AC 2006; 9:254-62. [PMID: 17348731 DOI: 10.1021/cc060054q] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alpha melanocyte stimulating hormone (alpha-MSH) is a widely distributed hormone. This tridecapeptide exhibits various biological activities mediated through different receptors. alpha-MSH binds to the melanocortin-1 receptor (MC1-R), mainly expressed in keratinocytes and melanocytes, inducing melanogenesis and anti-inflammatory processes. The central His-Phe-Arg-Trp tetrapeptide sequence of alpha-MSH is known to form a turn in the bioactive conformation. To find new potent analogs of alpha-MSH, we decided to introduce non-peptide building blocks in the alpha-MSH sequence. Molecular modeling studies showed that two amino acids of the central core sequence could be replaced by the benzodiazepinone building block without loosing the beta-turn conformation. Benzodiazepines are well-known pharmacophores exhibiting a wide scope of biological activities and are described as constrained dipeptide mimics templates. Although numerous synthetic pathways leading to benzodiazepinones have been described in literature, no methodology has 1,4-benzodiazepine-2,5-diones building blocks bearing a free carboxylic acid function and a protected amino function suitable for incorporation into peptide sequences. In this study, we report the synthesis of peptides with a benzodiazepinone moiety obtained directly during the course of solid-phase peptide synthesis (SPPS). This "on-line" strategy leads to the generation of a 54-member pseudo-peptide library of alpha-MSH analogs. After LC/MS purification, binding assays were performed on the MC1 receptor leading to the discovery of several micromolar ligands.
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Affiliation(s)
- Pascal Verdié
- Laboratoire des Aminoacides, Peptides et Protéines (LAPP), UMR 5810, Faculté de Pharmacie, Université de Montpellier I et II, 15 avenue Charles Flahault, 34060 Montpellier, France
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32
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Cain JP, Mayorov AV, Cai M, Wang H, Tan B, Chandler K, Lee Y, Petrov RR, Trivedi D, Hruby VJ. Design, synthesis, and biological evaluation of a new class of small molecule peptide mimetics targeting the melanocortin receptors. Bioorg Med Chem Lett 2006; 16:5462-7. [PMID: 16931008 PMCID: PMC1810397 DOI: 10.1016/j.bmcl.2006.07.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Revised: 06/23/2006] [Accepted: 07/05/2006] [Indexed: 10/24/2022]
Abstract
A new bicyclic template has been developed for the synthesis of peptide mimetics. Straightforward synthetic steps, starting from amino acids, allow the facile construction of a wide range of analogs. This system was designed to target the melanocortin receptors (MCRs), with functional group selection based on a known pharmacophore and guidance from molecular modeling to rationally identify positional and stereochemical isomers likely to be active. The functions of hMCRs are critical to myriad biological activities, including pigmentation, steroidogenesis, energy homeostasis, erectile activity, and inflammation. These G-protein-coupled receptors (GPCRs) are targets for drug discovery in a number of areas, including cancer, pain, and obesity therapeutics. All compounds from this series tested to date are antagonists which bind with high affinity. Importantly, many are highly selective for a particular MCR subtype, including some of the first completely hMC5R-selective antagonists reported.
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Affiliation(s)
- James P Cain
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
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33
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Nargund RP, Strack AM, Fong TM. Melanocortin-4 Receptor (MC4R) Agonists for the Treatment of Obesity. J Med Chem 2006; 49:4035-43. [PMID: 16821763 DOI: 10.1021/jm058241a] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ravi P Nargund
- Merck Research Laboratories, P.O. Box 2000, Rahway, New Jersey 07065, USA.
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34
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Mayorov AV, Han SY, Cai M, Hammer MR, Trivedi D, Hruby VJ. Effects of macrocycle size and rigidity on melanocortin receptor-1 and -5 selectivity in cyclic lactam alpha-melanocyte-stimulating hormone analogs. Chem Biol Drug Des 2006; 67:329-35. [PMID: 16784457 PMCID: PMC1851940 DOI: 10.1111/j.1747-0285.2006.00383.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The effects of the linker arm rigidity and size on melanocortin receptor selectivity were explored in a series of compounds using cyclic lactam alpha-melanocyte-stimulating hormone template. A variety of dicarboxylic acid linkers introduced between the alpha-amino group of His(6) and the epsilon-amino group of Lys(10) lead to high-affinity, selective human melanocortin receptor-1 and -5 (hMC1R and hMC5R) antagonists. The incorporation of hydrophilic functions into the linker arm was found to be unfavorable for both binding potency and receptor selectivity. Analogs 8 and 9 containing highly conformationally constrained hydrophobic linkers (m- and p-phthalic acids) were found to be selective nanomolar range hMC1R antagonists (IC(50) = 7 and 4 nm, respectively), whereas the employment of a small conformationally constrained linker (maleic acid) resulted in a high-affinity (IC(50) = 19 nm) and selective hMC5R antagonist (analog 12). These newly developed melanotropins will serve as critical biochemical tools for elucidating the full spectrum of functions performed by the physiologically important melanocortin-1 and -5 receptors.
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Key Words
- α-melanocyte-stimulating hormone
- antagonist
- human melanocortin-1 receptor
- human melanocortin-5 receptor
- macrocyclic
- melanocortin
- peptide
- all, allyl
- alloc, allyloxycarbonyl
- boc, tert-butyloxycarbonyl
- fmoc, fluorenylmethoxycarbonyl
- ch3cn, acetonitrile
- dcm, dichloromethane
- dipea, diisopropylethylamine
- dmf, n,n-dimethylformamide
- dic, diisopropyl carbodiimide
- hbtu, 2-(1h-benzotriazole-1-yl)-1, 1, 3, 3-tetramethyluronium hexafluorophosphate
- hobt, n-hydroxybenzotriazole
- hmcr, human melanocortin receptor
- msh, melanocyte-stimulating hormone
- nal(2′), 2′-naphthylalanine
- pbf, 2, 2, 4, 6, 7-pentamethyldihydrobenzofuran-5-sulfonyl
- pybop, benzotriazol-1-yloxy-tris-pyrrolidinophosphonium hexafluorophosphate
- tfa, trifluoroacetic acid
- trt, trityl
- spps, solid-phase peptide synthesis
- rp-hplc, reverse-phase high-performance liquid chromatography
- hmc1r, human melanocortin-1 receptor
- α-msh, ac-ser-tyr-ser-met-glu-his-phe-arg-trp-gly-lys-pro-val-nh2
- ndp-α-msh, ac-ser-tyr-ser-nle-glu-his-d-phe-arg-trp-gly-lys-pro-val-nh2
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MESH Headings
- Adenylyl Cyclases/metabolism
- Binding, Competitive
- Cell Line
- Drug Design
- Humans
- Kidney/cytology
- Kidney/metabolism
- Lactams, Macrocyclic/chemistry
- Molecular Structure
- Receptor, Melanocortin, Type 1/agonists
- Receptor, Melanocortin, Type 1/antagonists & inhibitors
- Receptor, Melanocortin, Type 1/metabolism
- Receptors, Corticotropin/agonists
- Receptors, Corticotropin/antagonists & inhibitors
- Receptors, Corticotropin/metabolism
- Receptors, Melanocortin
- Transfection
- alpha-MSH/analogs & derivatives
- alpha-MSH/chemistry
- alpha-MSH/metabolism
- alpha-MSH/pharmacology
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Affiliation(s)
| | - So-Yeop Han
- Department of Chemistry, Division of Molecular Life Sciences, Ewha Womans University, Seoul 120-750, South Korea
| | - Minying Cai
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Matthew R. Hammer
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Dev Trivedi
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Victor J. Hruby
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
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Mayorov AV, Cai M, Chandler KB, Petrov RR, Van Scoy AR, Yu Z, Tanaka DK, Trivedi D, Hruby VJ. Development of cyclic gamma-MSH analogues with selective hMC3R agonist and hMC3R/hMC5R antagonist activities. J Med Chem 2006; 49:1946-52. [PMID: 16539382 PMCID: PMC1484467 DOI: 10.1021/jm0510326] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A series of cyclic lactam analogues of gamma-MSH (H-Tyr1-Val2-Met3-Gly4-His5-Phe6-Arg7-Trp8-Asp9-Arg10-Phe11-Gly12-OH) with a bulky hydrophobic residue in the direct proximity to the pharmacophore (Xaa-D-Phe/D-Nal(2')-Arg-Trp) were designed and synthesized by solid-phase methods. A variety of amino acids with a broad range of hydrophobic/hydrophilic properties was introduced in position 5 to further explore their complementary role in receptor selectivity. Biological evaluation of these peptides revealed several analogues with potent hMC3R agonist and hMC3R/hMC5R antagonist activities, and good receptor selectivity. Analogue 4, c[Nle-Arg-D-Phe-Arg-Trp-Glu]-NH2, was found to be a very potent and selective hMC3R agonist (EC50=1.2 nM, 112% act). In addition, analogue 13, c[Nle-Val-D-Nal(2')-Arg-Trp-Glu]-NH2, was identified as an hMC3R/hMC5R antagonist with the best selectivity against the hMC4R in this series (pA2(hMC3R)=8.4; pA2(hMC5R)=8.7). These results indicate the significance of steric factors in melanocortin receptor selectivity and suggest that introduction of bulky residues in the direct proximity to the melanocortin pharmacophore is an effective approach to design of novel hMC3R and hMC5R selective ligands.
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MESH Headings
- Adenylyl Cyclases/biosynthesis
- Binding, Competitive
- Cell Line
- Drug Design
- Humans
- Hydrophobic and Hydrophilic Interactions
- Lactams/chemical synthesis
- Lactams/chemistry
- Lactams/pharmacology
- Models, Molecular
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/pharmacology
- Radioligand Assay
- Receptor, Melanocortin, Type 3/agonists
- Receptor, Melanocortin, Type 3/antagonists & inhibitors
- Receptor, Melanocortin, Type 3/chemistry
- Receptors, Corticotropin/antagonists & inhibitors
- Receptors, Corticotropin/chemistry
- Receptors, Melanocortin
- Structure-Activity Relationship
- gamma-MSH/chemistry
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Affiliation(s)
| | - Minying Cai
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Kevin B. Chandler
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Ravil R. Petrov
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - April R. Van Scoy
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Zerui Yu
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Dustin K. Tanaka
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Dev Trivedi
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Victor J. Hruby
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
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36
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Grieco P, Cai M, Mayorov AV, Trivedi D, Hruby VJ. Structure-activity studies of new melanocortin peptides containing an aromatic amino acid at the N-terminal position. Peptides 2006; 27:472-81. [PMID: 16303211 PMCID: PMC1483901 DOI: 10.1016/j.peptides.2005.01.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 01/16/2005] [Indexed: 10/25/2022]
Abstract
Cyclic melanotropin peptides, designed with an aromatic amino acid substitution at the N-terminal position of the MT-II-type scaffold, were prepared by solid-phase peptide synthesis and evaluated for their ability to bind to and activate human melanocortin-1, -3, -4, and -5 receptors. The structure-activity studies of these MT-II analogues have identified a selective antagonist at the hMC4R (H-Phe-c[Asp-Pro-d-Nal(2')-Arg-Trp-Gly-Lys]-NH(2), pA(2)=8.7), a selective partial agonist at the hMC4R (H-d-Nal(2')-c[Asp-Pro-d-Phe-Arg-Trp-Gly-Lys]-NH(2), IC(50)=11nM, EC(50)=56nM), and a selective partial agonist at the hMC3R (H-d-Phe-c[Asp-Pro-d-Phe-Arg-Trp-Lys]-NH(2), IC(50)=3.7nM, EC(50)=4.9nM). Aromatic amino acid substitution at the N-terminus in conjuction with the expansion of the 23-membered cyclic lactam MT-II scaffold to a 26-membered scaffold by addition of a Gly residue in position 10 leads to melanotropin peptides with enhanced receptor selectivity.
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Affiliation(s)
- Paolo Grieco
- Department of Pharmaceutical Chemistry and Toxicology, University of Napoli “Federico II”, Via D. Montesano, 49, 80131 Napoli, Italy
| | - Minying Cai
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | | | - Dev Trivedi
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Victor J. Hruby
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
- * Corresponding author. Tel.: +1 520 621 6332; fax: +1 520 621 8407. E-mail address: (V.J. Hruby)
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37
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Fernandez RM, Vieira RFF, Nakaie CR, Lamy MT, Ito AS. Acid-base titration of melanocortin peptides: evidence of Trp rotational conformers interconversion. Biopolymers 2005; 80:643-50. [PMID: 15657882 DOI: 10.1002/bip.20210] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Tryptophantime-resolved fluorescence was used to monitor acid-base titration properties of alpha-melanocyte stimulating hormone (alpha-MSH) and the biologically more potent analog [Nle4, D-Phe7]alpha -MSH (NDP-MSH), labeled or not with the paramagnetic amino acid probe 2,2,6,6-tetramthylpiperidine-N-oxyl-4-amino-4-carboxylic acid (Toac). Global analysis of fluorescence decay profiles measured in the pH range between 2.0 and 11.0 showed that, for each peptide, the data could be well fitted to three lifetimes whose values remained constant. The less populated short lifetime component changed little with pH and was ascribed to Trp g+ chi1 rotamer, in which electron transfer deactivation predominates over fluorescence. The long and intermediate lifetime preexponential factors interconverted along that pH interval and the result was interpreted as due to interconversion between Trp g- and trans chi1 rotamers, driven by conformational changes promoted by modifications in the ionization state of side-chain residues. The differences in the extent of interconversion in alpha-MSH and NDP-MSH are indicative of structural differences between the peptides, while titration curves suggest structural similarities between each peptide and its Toac-labeled species, in aqueous solution. Though less sensitive than fluorescence, the Toac electron spin resonance (ESR) isotropic hyperfine splitting parameter can also monitor the titration of side-chain residues located relatively far from the probe.
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38
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Hsiung HM, Hertel J, Zhang XY, Smith DP, Smiley DL, Heiman ML, Yang DD, Husain S, Mayer JP, Zhang L, Mo H, Yan LZ. A novel and selective beta-melanocyte-stimulating hormone-derived peptide agonist for melanocortin 4 receptor potently decreased food intake and body weight gain in diet-induced obese rats. Endocrinology 2005; 146:5257-66. [PMID: 16166226 DOI: 10.1210/en.2005-0177] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
alphaMSH has generally been accepted as the endogenous ligand for melanocortin 4 receptor (MC4R), which plays a major role in energy homeostasis. Targeting MC4R to develop antiobesity agents, many investigators have performed a structure-activity relationship (SAR) studies based on alphaMSH structure. In this report, we performed a SAR study using human betaMSH (5 - 22) (DEGPYRMEHFRWGSPPKD, peptide 1) as a lead sequence to develop potent and selective agonists for MC4R and MC3R. The SAR study was begun with a truncation of N terminus of betaMSH (5 - 22) together with acetylation of the N terminus and amidation of the C terminus of the peptide. Introduction of a cyclic disulfide constrain and replacement of L-Phe with D-Phe afforded a super potent agonist (peptide 5). Furthermore truncation at the C terminus generated a small and potent MC4R and MC3R agonist (Ac-YRcyclo[CEHdFRWC]amide, peptide 6), which exhibited no MC5R and greatly reduced MC1R activity. Molecular modeling of Ac-YRcyclo[CEHdFRWC]amide (peptide 6) revealed that Arg2 in the peptide formed a salt bridge with Glu4. Subcutaneous or intracerebroventricular administration of peptide 6 in rats showed potent in vivo efficacy as evidenced by its effects in reducing energy balance, increasing fat use, and decreasing weight gain in both acute and chronic rat metabolic studies. Furthermore, the antiobesity effect by peptide 6 was manifested only in wild-type but not MC4R-deficient mice, indicating that antiobesity effects of the peptide were attributed largely through MC4R but not MC3R agonist activity of the peptide.
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Affiliation(s)
- Hansen M Hsiung
- Division of Endocrine Research, Eli Lilly & Co., Indianapolis, Indiana 46285, USA.
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39
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Fung S, Hruby VJ. Design of cyclic and other templates for potent and selective peptide alpha-MSH analogues. Curr Opin Chem Biol 2005; 9:352-8. [PMID: 16023401 PMCID: PMC1820743 DOI: 10.1016/j.cbpa.2005.06.010] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2005] [Accepted: 06/22/2005] [Indexed: 11/19/2022]
Abstract
For over three decades, the design of linear peptide ligands often has incorporated cyclic constraints to improve potency, receptor selectivity, proteolytic stability and biodistribution. Its importance has been so well established that modern day schemes for ligand-based drug design often start with cyclization of linear peptides to rigidify peptide structure, to limit its conformational possibilities, and to find key pharmacophore elements in three-dimensional space. In the past several years, cyclic constraints have been used to develop ligands with improved efficacy, binding affinity, biostability and receptor selectivity for alpha-melanocyte-stimulating hormone (alpha-MSH). Furthermore, potent cyclic alpha-MSH analogues, such as MT-II and SHU-9119, have made structure-activity relationship studies and molecular modeling more useful for creating new three-dimensional, topographical pharmacophore templates.
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40
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Pogozheva ID, Chai BX, Lomize AL, Fong TM, Weinberg DH, Nargund RP, Mulholland MW, Gantz I, Mosberg HI. Interactions of human melanocortin 4 receptor with nonpeptide and peptide agonists. Biochemistry 2005; 44:11329-41. [PMID: 16114870 PMCID: PMC2532597 DOI: 10.1021/bi0501840] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Specific interactions of human melanocortin-4 receptor (hMC4R) with its nonpeptide and peptide agonists were studied using alanine-scanning mutagenesis. The binding affinities and potencies of two synthetic, small-molecule agonists (THIQ, MB243) were strongly affected by substitutions in transmembrane alpha-helices (TM) 2, 3, 6, and 7 (residues Glu(100), Asp(122), Asp(126), Phe(261), His(264), Leu(265), and Leu(288)). In addition, a I129A mutation primarily affected the binding and potency of THIQ, while F262A, W258A, Y268A mutations impaired interactions with MB243. By contrast, binding affinity and potency of the linear peptide agonist NDP-MSH were substantially reduced only in D126A and H264A mutants. Three-dimensional models of receptor-ligand complexes with their agonists were generated by distance-geometry using the experimental, homology-based, and other structural constraints, including interhelical H-bonds and two disulfide bridges (Cys(40)-Cys(279), Cys(271)-Cys(277)) of hMC4R. In the models, all pharmacophore elements of small-molecule agonists are spatially overlapped with the corresponding key residues (His(6), d-Phe(7), Arg(8), and Trp(9)) of the linear peptide: their charged amine groups interact with acidic residues from TM2 and TM3, similar to His(6) and Arg(6) of NDP-MSH; their substituted piperidines mimic Trp(9) of the peptide and interact with TM5 and TM6, while the d-Phe aromatic rings of all three agonists contact with Leu(133), Trp(258), and Phe(261) residues.
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MESH Headings
- Amino Acid Sequence
- Binding Sites
- Cyclic AMP/pharmacology
- Humans
- Models, Molecular
- Molecular Sequence Data
- Mutagenesis, Site-Directed
- Peptides/pharmacology
- Piperazines/pharmacology
- Piperidines/pharmacology
- Protein Structure, Secondary
- Receptor, Melanocortin, Type 4/agonists
- Receptor, Melanocortin, Type 4/chemistry
- Receptor, Melanocortin, Type 4/drug effects
- Receptor, Melanocortin, Type 4/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/drug effects
- Recombinant Proteins/metabolism
- Rhodopsin/chemistry
- Sequence Alignment
- Sequence Homology, Amino Acid
- Transfection
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Affiliation(s)
- Irina D Pogozheva
- Department of Medicinal Chemistry, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109, USA
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Fernandez RM, Vieira RFF, Nakaie CR, Ito AS, Lamy MT. Peptide-lipid interaction monitored by spin labeled biologically active melanocortin peptides. Peptides 2005; 26:1825-34. [PMID: 16006009 DOI: 10.1016/j.peptides.2004.12.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2004] [Accepted: 12/07/2004] [Indexed: 10/25/2022]
Abstract
The present work comparatively analyzes the interaction of alpha-MSH and its more potent and long-acting analog [Nle4, D-Phe7]alpha-MSH (NDP-MSH) with lipid bilayers. The peptides were spin labeled with Toac (2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid) at the N-terminal, as those derivatives had been previously shown to keep their full biological activity. Due to the special rigidity of the Toac covalent binding to the peptide molecule, this spin label is highly sensitive to the peptide backbone conformation and dynamics. The peptides were investigated both by the electron spin resonance (ESR) of Toac0 and the time resolved fluorescence of Trp9 present in the peptides. The Toac0 ESR of the membrane-bound peptides indicates that the two peptides are inserted into the bilayer, close to the bilayer surface, in rather similar environments. A residue titration around pKa 7.5, possibly that of His6, can be clearly monitored by peptide-lipid partition. Trp9 time resolved fluorescence indicates that the peptides, and their Toac-labeled derivatives, present rather similar conformations when membrane bound, though Trp9 in NDP-MSH, and in its Toac-labeled derivative, goes somewhat further down into the bilayer. Yet, Toac0 ESR signal shows that the Toac-labeled N-terminal of NDP-MSH is in a shallower position in the bilayer, as compared to the hormone.
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Affiliation(s)
- Roberto M Fernandez
- Instituto de Física, Universidade de São Paulo, CP 66318, CEP 05315-970, São Paulo, SP, Brazil
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Cai M, Mayorov AV, Ying J, Stankova M, Trivedi D, Cabello C, Hruby VJ. Design of novel melanotropin agonists and antagonists with high potency and selectivity for human melanocortin receptors. Peptides 2005; 26:1481-5. [PMID: 15876475 DOI: 10.1016/j.peptides.2005.03.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
alpha-MSH and gamma-MSH are the natural endogenous hormones for the human melanocortin-1, 3, 4 and 5 receptors (hMC1R, hMC3R, hMC4R and hMC5R). These and more potent, stable and prolonged acting analogues such as NDP-alpha-MSH, MT-II and SHU-9119 are not very receptor selective. To develop potent and selective agonist and antagonist ligands for the melanocortin receptors we have used state-of-the-art biophysical studies, computational chemistry, and design of conformational and topographical constraints with novel templates.
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Affiliation(s)
- Minying Cai
- Biochemistry and Molecular Biophysics, University of Arizona, Tucson, AZ 85721, USA
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Wilczynski A, Wilson KR, Scott JW, Edison AS, Haskell-Luevano C. Structure-activity relationships of the unique and potent agouti-related protein (AGRP)-melanocortin chimeric Tyr-c[beta-Asp-His-DPhe-Arg-Trp-Asn-Ala-Phe-Dpr]-Tyr-NH2 peptide template. J Med Chem 2005; 48:3060-75. [PMID: 15828845 DOI: 10.1021/jm049010r] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The melanocortin receptor system consists of endogenous agonists, antagonists, G-protein coupled receptors, and auxiliary proteins that are involved in the regulation of complex physiological functions such as energy and weight homeostasis, feeding behavior, inflammation, sexual function, pigmentation, and exocrine gland function. Herein, we report the structure-activity relationship (SAR) of a new chimeric hAGRP-melanocortin agonist peptide template Tyr-c[beta-Asp-His-DPhe-Arg-Trp-Asn-Ala-Phe-Dpr]-Tyr-NH(2) that was characterized using amino acids previously reported in other melanocortin agonist templates. Twenty peptides were examined in this study, and six peptides were selected for (1)H NMR and computer-assisted molecular modeling structural analysis. The most notable results include the identification that modification of the chimeric template at the His position with Pro and Phe resulted in ligands that were nM mouse melanocortin-3 receptor (mMC3R) antagonists and nM mouse melanocortin-4 receptor (mMC4R) agonists. The peptides Tyr-c[beta-Asp-His-DPhe-Ala-Trp-Asn-Ala-Phe-Dpr]-Tyr-NH(2) and Tyr-c[beta-Asp-His-DNal(1')-Arg-Trp-Asn-Ala-Phe-Dpr]-Tyr-NH(2) resulted in 730- and 560-fold, respectively, mMC4R versus mMC3R selective agonists that also possessed nM agonist potency at the mMC1R and mMC5R. Structural studies identified a reverse turn occurring in the His-DPhe-Arg-Trp domain, with subtle differences observed that may account for the differences in melanocortin receptor pharmacology. Specifically, a gamma-turn secondary structure involving the DPhe(4) in the central position of the Tyr-c[beta-Asp-Phe-DPhe-Arg-Trp-Asn-Ala-Phe-Dpr]-Tyr-NH(2) peptide may differentiate the mixed mMC3R antagonist and mMC4R agonist pharmacology.
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MESH Headings
- Agouti-Related Protein
- Animals
- Binding, Competitive
- Cell Line
- Drug Design
- Humans
- Intercellular Signaling Peptides and Proteins
- Magnetic Resonance Spectroscopy
- Mice
- Models, Molecular
- Oligopeptides/chemical synthesis
- Oligopeptides/chemistry
- Oligopeptides/pharmacology
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/pharmacology
- Protein Structure, Secondary
- Proteins/chemistry
- Receptor, Melanocortin, Type 3/antagonists & inhibitors
- Receptor, Melanocortin, Type 4/agonists
- Receptors, Melanocortin/agonists
- Receptors, Melanocortin/antagonists & inhibitors
- Structure-Activity Relationship
- alpha-MSH/chemistry
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Affiliation(s)
- Andrzej Wilczynski
- University of Florida, Department of Medicinal Chemistry and Biochemistry, Gainesville, Florida 32610, USA
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Cai M, Mayorov AV, Cabello C, Stankova M, Trivedi D, Hruby VJ. Novel 3D pharmacophore of alpha-MSH/gamma-MSH hybrids leads to selective human MC1R and MC3R analogues. J Med Chem 2005; 48:1839-48. [PMID: 15771429 DOI: 10.1021/jm049579s] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To further evaluate elements that could contribute to the 3D topographical structure of gamma-MSH, we have systematically designed a group of linear gamma-MSH analogues and evaluated their biological activities: without a N-terminal acetyl, with and without a C-terminal amide, with Nle(3), with l- or d-Phe(6) or d-Nal(2')(6), and with d-Trp(8) or d-Nal(2')(8). It was found that changing the C-terminal acid in gamma-MSH to an amide and replacing Met with Nle leads to increased binding affinities at all four subtypes of melanocortin receptors (10-100 fold). Substitution of Trp(8) with d-Nal(2')(8) and Phe(6) with d-Phe(6) in gamma-MSH-NH(2) forms a selective antagonist for the hMC3R, whereas, substitution of Phe(6) with d-Nal(2')(6) and replacing Trp(8) with d-Trp(8) at gamma-MSH-NH(2) yields a selective partial agonist for the hMC1R. Finally, substitution of His(5) with Pro(5) and Trp(8) with d-Nal(2')(8) in gamma-MSH-NH(2) leads to a highly potent and selective agonist for the hMC1R. Molecular modeling showed that, at the C-terminal of Nle(3)-gamma-MSH-NH(2), there is a reverse-turn-like structure, suggesting that there might be a secondary binding site involved in ligand-receptor interaction for gamma-MSH analogues that may explain the enhanced binding affinities of the Nle(3)-gamma-MSH-NH(2) analogues. Our results indicate that increasing the hydrophobicity and replacing Phe(6) and Trp(8) with bulkier aromatic amino acid residues is very important for selectivity of alpha-MSH/gamma-MSH hybrids for hMCRs.
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Affiliation(s)
- Minying Cai
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA
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