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Reynaud S, Laurin SA, Ciolek J, Barbe P, Van Baelen AC, Susset M, Blondel F, Ghazarian M, Boeri J, Vanden Driessche M, Upert G, Mourier G, Kessler P, Konnert L, Beroud R, Keck M, Servent D, Bouvier M, Gilles N. From a Cone Snail Toxin to a Competitive MC4R Antagonist. J Med Chem 2022; 65:12084-12094. [PMID: 36063022 DOI: 10.1021/acs.jmedchem.2c00786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The melanocortin 4 receptor (MC4R) plays a role in energy homeostasis and represents a target for treating energy balance disorders. For decades, synthetic ligands have been derived from MC4R endogenous agonists and antagonists, such as setmelanotide used to treat rare forms of genetic obesity. Recently, animal venoms have demonstrated their capacity to provide melanocortin ligands with toxins from a scorpion and a spider. Here, we described a cone snail toxin, N-CTX-Ltg1a, with a nanomolar affinity for hMC4R but unrelated to any known toxins or melanocortin ligands. We then derived from the conotoxin the linear peptide HT1-0, a competitive antagonist of Gs, G15, and β-arrestin2 pathways with a low nanomolar affinity for hMC4R. Similar to endogenous ligands, HT1-0 needs hydrophobic and basic residues to bind hMC4R. Altogether, it represents the first venom-derived peptide of high affinity on MC4R and paves the way for the development of new MC4R antagonists.
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Affiliation(s)
- Steve Reynaud
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Suli-Anne Laurin
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Justyna Ciolek
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Peggy Barbe
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Anne-Cécile Van Baelen
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Michaël Susset
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Florian Blondel
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Marine Ghazarian
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Julia Boeri
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Margot Vanden Driessche
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Grégory Upert
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Gilles Mourier
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Pascal Kessler
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Laure Konnert
- Smartox Biotechnology, 6 Rue des Platanes, 38120 Saint-Egrève, France
| | - Rémy Beroud
- Smartox Biotechnology, 6 Rue des Platanes, 38120 Saint-Egrève, France
| | - Mathilde Keck
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Denis Servent
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
| | - Michel Bouvier
- Institute for Research in Immunology and Cancer, Department of Biochemistry and Molecular Medicine, Université de Montréal, Montréal, Québec H3T 1J4, Canada
| | - Nicolas Gilles
- Health and Life Sciences Department, Université Paris Saclay, French Alternative Energies and Atomic Energy Commission (CEA), CEA Saclay, Bat 152, 91191 Gif sur Yvette, France
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Yeo GSH, Chao DHM, Siegert AM, Koerperich ZM, Ericson MD, Simonds SE, Larson CM, Luquet S, Clarke I, Sharma S, Clément K, Cowley MA, Haskell-Luevano C, Van Der Ploeg L, Adan RAH. The melanocortin pathway and energy homeostasis: From discovery to obesity therapy. Mol Metab 2021; 48:101206. [PMID: 33684608 PMCID: PMC8050006 DOI: 10.1016/j.molmet.2021.101206] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 02/08/2023] Open
Abstract
Background Over the past 20 years, insights from human and mouse genetics have illuminated the central role of the brain leptin-melanocortin pathway in controlling mammalian food intake, with genetic disruption resulting in extreme obesity, and more subtle polymorphic variations influencing the population distribution of body weight. At the end of 2020, the U.S. Food and Drug Administration (FDA) approved setmelanotide, a melanocortin 4 receptor agonist, for use in individuals with severe obesity due to either pro-opiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) deficiency. Scope of review Herein, we chart the melanocortin pathway's history, explore its pharmacology, genetics, and physiology, and describe how a neuropeptidergic circuit became an important druggable obesity target. Major conclusions Unravelling the genetics of the subset of severe obesity has revealed the importance of the melanocortin pathway in appetitive control; coupling this with studying the molecular pharmacology of compounds that bind melanocortin receptors has brought a new obesity drug to the market. This process provides a drug discovery template for complex disorders, which for setmelanotide took 25 years to transform from a single gene into an approved drug.
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Affiliation(s)
- Giles S H Yeo
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
| | | | - Anna-Maria Siegert
- MRC Metabolic Diseases Unit, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
| | - Zoe M Koerperich
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA 55455.
| | - Mark D Ericson
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA 55455.
| | - Stephanie E Simonds
- Metabolism, Diabetes, and Obesity Programme, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia.
| | - Courtney M Larson
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA 55455.
| | - Serge Luquet
- Université de Paris, BFA, UMR 8251, CNRS, Paris, France.
| | - Iain Clarke
- Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, VIC 3010, Australia.
| | | | - Karine Clément
- Assistance Publique Hôpitaux de Paris, Nutrition Department, Pitié-Salpêtrière Hospital, Paris, France, Sorbonne Université, INSERM, Nutrition and Obesity: Systemic Approaches (NutriOmics) Research Unit, Paris, France.
| | - Michael A Cowley
- Metabolism, Diabetes, and Obesity Programme, Monash Biomedicine Discovery Institute, and Department of Physiology, Monash University, Clayton, Victoria, Australia.
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA 55455.
| | | | - Roger A H Adan
- Department of Translational Neuroscience, UMCU Brain Centre, University Medical Centre Utrecht, Utrecht University, the Netherlands; Institute of Neuroscience and Physiology, Sahlgrenska Academy at the University of Gothenburg, Sweden.
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3
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Ericson MD, Haslach EM, Schnell SM, Freeman KT, Xiang ZM, Portillo FP, Speth R, Litherland SA, Haskell-Luevano C. Discovery of Molecular Interactions of the Human Melanocortin-4 Receptor (hMC4R) Asp189 (D189) Amino Acid with the Endogenous G-Protein-Coupled Receptor (GPCR) Antagonist Agouti-Related Protein (AGRP) Provides Insights to AGRP's Inverse Agonist Pharmacology at the hMC4R. ACS Chem Neurosci 2021; 12:542-556. [PMID: 33470098 DOI: 10.1021/acschemneuro.0c00755] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The melanocortin receptors (MCRs) are important for numerous biological pathways, including feeding behavior and energy homeostasis. In addition to endogenous peptide agonists, this receptor family has two naturally occurring endogenous antagonists, agouti and agouti-related protein (AGRP). At the melanocortin-4 receptor (MC4R), the AGRP ligand functions as an endogenous inverse agonist in the absence of agonist and as a competitive antagonist in the presence of agonist. At the melanocortin-3 receptor (MC3R), AGRP functions solely as a competitive antagonist in the presence of agonist. The molecular interactions that differentiate AGRP's inverse agonist activity at the MC4R have remained elusive until the findings reported herein. Upon the basis of homology molecular modeling approaches, we previously postulated a unique interaction between the D189 position of the hMC4R and Asn114 of AGRP. To further test this hypothesis, six D189 mutant hMC4Rs (D189A, D189E, D189N, D189Q, D189S, and D189K) were generated and pharmacologically characterized resulting in the discovery of differences in inverse agonist activity of AGRP and an 11 macrocyclic compound library. These data support the hypothesized interaction between the hMC4R D189 position and Asn114 residue of AGRP and define critical ligand-receptor molecular interactions responsible for the inverse agonist activity of AGRP at the hMC4R.
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Affiliation(s)
- Mark D. Ericson
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Erica M. Haslach
- Departments of Pharmacodynamics and Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Sathya M. Schnell
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Zhimin M. Xiang
- Departments of Pharmacodynamics and Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Frederico P. Portillo
- Departments of Pharmacodynamics and Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Robert Speth
- College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida 33328, United States
- College of Medicine, Georgetown University, Washington, D.C. 20057, United States
| | - Sally A. Litherland
- Translational Research, Florida Hospital Cancer Institute, Orlando, Florida 32804, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
- Departments of Pharmacodynamics and Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
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4
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Ericson MD, Freeman KT, Haskell-Luevano C. Peptoid NPhe 4 in AGRP-Based c[Pro 1-Arg 2-Phe 3-Phe 4-Xxx 5-Ala 6-Phe 7-DPro 8] Scaffolds Maintain Mouse MC4R Antagonist Potency. ACS Med Chem Lett 2020; 11:1942-1948. [PMID: 33062177 DOI: 10.1021/acsmedchemlett.9b00641] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Accepted: 03/26/2020] [Indexed: 01/12/2023] Open
Abstract
The melanocortin receptors are involved in numerous physiological functions and are regulated by agonists derived from the proopiomelanocortin gene transcript and two endogenous antagonists, agouti and agouti-related protein (AGRP). The key binding and functional determinant of AGRP, an MC3R and MC4R antagonist, is an Arg-Phe-Phe tripeptide sequence located on an exposed hexapeptide (Arg-Phe-Phe-Asn-Ala-Phe) loop. It has previously been observed that cyclizing this sequence through a DPro-Pro motif (c[Pro1-Arg2-Phe3-Phe4-Asn5-Ala6-Phe7-DPro8]) resulted in a macrocyclic scaffold with MC4R antagonist activity, with increased MC4R potency when a diaminopropionic acid (Dap) residue is substituted at position 5. In this report, a series of 11 single-peptoid substitutions were performed in the AGRP-derived macrocycles. While most peptoid substitutions decreased MC4R antagonist potency, it was observed that NPhe4 (compounds 4 and 11) or NDab5 (diaminobutyric acid, compound 7) maintained MC4R antagonist potency. The NPhe4 substitutions also resulted in MC5R antagonist and inverse agonist activity equipotent to the parent scaffolds. These data may be used in the design of future MC4R and MC5R antagonist leads and probes that possess increased metabolic stability due to the presence of peptoid residues.
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Affiliation(s)
- Mark D. Ericson
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
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5
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Fleming KA, Freeman KT, Ericson MD, Haskell-Luevano C. Synergistic Multiresidue Substitutions of a Macrocyclic c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-dPro] Agouti-Related Protein (AGRP) Scaffold Yield Potent and >600-Fold MC4R versus MC3R Selective Melanocortin Receptor Antagonists. J Med Chem 2018; 61:7729-7740. [PMID: 30035543 PMCID: PMC6174881 DOI: 10.1021/acs.jmedchem.8b00684] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Antagonist ligands of the melanocortin-3 and -4 receptors (MC3R, MC4R), including agouti-related protein (AGRP), are postulated to be targets for the treatment of diseases of negative energy balance. Previous studies reported the macrocyclic MC3R/MC4R antagonist c[Pro1-Arg2-Phe3-Phe4-Asn5-Ala6-Phe7-dPro8], which is 250-fold less potent at the mouse (m) mMC3R and 3-fold less potent at the mMC4R than AGRP. Previous studies explored the structure-activity relationships around individual positions in this template. Herein, a multiresidue substitution strategy is utilized, combining the lead sequence with hPhe4, Dap5, Arg5, Ser6, and Nle7 substitutions previously reported. Two compounds from this study (16, 20) contain an hPhe4/Ser6/Nle7 substitution pattern, are 3-6-fold more potent than AGRP at the mMC4R and are 600-800-fold selective for the mMC4R over the mMC3R. Another lead compound (21), possessing the hPhe4/Arg5 substitutions, is only 5-fold less potent than AGRP at the mMC3R and is equipotent to AGRP at the mMC4R.
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Affiliation(s)
- Katlyn A. Fleming
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
| | - Mark D. Ericson
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
| | - Carrie Haskell-Luevano
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
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6
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Tala SR, Singh A, Lensing CJ, Schnell SM, Freeman KT, Rocca JR, Haskell-Luevano C. 1,2,3-Triazole Rings as a Disulfide Bond Mimetic in Chimeric AGRP-Melanocortin Peptides: Design, Synthesis, and Functional Characterization. ACS Chem Neurosci 2018; 9:1001-1013. [PMID: 29257879 DOI: 10.1021/acschemneuro.7b00422] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The melanocortin system is involved in the regulation of complex physiological functions, including energy and weight homeostasis, feeding behavior, inflammation, sexual function, pigmentation, and exocrine gland function. The five melanocortin receptors that belong to the superfamily of G protein-coupled receptors (GPCRs) are regulated by endogenously expressed agonists and antagonists. The aim of this study was to explore the potential of replacing the disulfide bridge in chimeric AGRP-melanocortin peptide Tyr-c[Cys-His-d-Phe-Arg-Trp-Asn-Ala-Phe-Cys]-Tyr-NH2 (1) with 1,2,3-triazole moieties. A series of 1,2,3-triazole-bridged peptidomimetics were designed, synthesized, and pharmacologically evaluated at the mouse melanocortin receptors. The ligands possessed nanomolar to micromolar agonist cAMP signaling potency. A key finding was that the disulfide bond in peptide 1 can be replaced with the monotriazole ring with minimal effect on the functional activity at the melanocortin receptors. The 1,5-disubstituted triazole-bridged peptide 6 showed equipotent functional activity at the mMC3R and modest 5-fold decreased agonist potency at the mMC4R compared to those of 1. Interestingly, the 1,4- and 1,5-disubstituted isomers of the triazole ring resulted in different selectivities at the receptor subtypes, indicating subtle structural features that may be exploited in the generation of selective melanocortin ligands. Introducing cyclic and acyclic bis-triazole moieties into chimeric AGRP template 1 generally decreased agonist activity. These results will be useful for the further design of neuronal chemical probes for the melanocortin receptors as well as in other receptor systems.
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Affiliation(s)
- Srinivasa R. Tala
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Anamika Singh
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Cody J. Lensing
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sathya M. Schnell
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - James R. Rocca
- Advanced Magnetic Resonance Imaging and Spectroscopy, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
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7
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Fleming KA, Ericson MD, Freeman KT, Adank DN, Lunzer MM, Wilber SL, Haskell-Luevano C. Structure-Activity Relationship Studies of a Macrocyclic AGRP-Mimetic Scaffold c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-DPro] Yield Potent and Selective Melanocortin-4 Receptor Antagonists and Melanocortin-5 Receptor Inverse Agonists That Increase Food Intake in Mice. ACS Chem Neurosci 2018; 9:1141-1151. [PMID: 29363944 PMCID: PMC5955836 DOI: 10.1021/acschemneuro.7b00495] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The melanocortin system has five receptors, and antagonists of the central melanocortin receptors (MC3R, MC4R) are postulated to be viable therapeutics for disorders of negative energy balance such as anorexia, cachexia, and failure to thrive. Agouti-related protein (AGRP) is an antagonist of the MC3R and an antagonist/inverse agonist of the MC4R. Biophysical NMR-based structural studies have demonstrated that the active sequence of this hormone, Arg-Phe-Phe, is located on an exposed β-hairpin loop. It has previously been demonstrated that the macrocyclic octapeptide scaffold c[Pro1-Arg2-Phe3-Phe4-Asn5-Ala6-Phe7-DPro8] is 16-fold less potent than AGRP at the mouse MC4R (mMC4R). Herein it was hypothesized that the Phe7 position may be substituted to produce more potent and/or selective melanocortin receptor antagonist ligands based on this template. A 10-membered library was synthesized that substituted small (Gly), polar (Ser), acidic (Asp), basic (Lys), aliphatic (Leu, Nle, and Cha), and aromatic (Trp, Tyr, hPhe) amino acids to explore potential modifications at the Phe7 position. The most potent mMC4R antagonist contained a Nle7 substitution, was equipotent to the lead ligand 200-fold selective for the mMC4R over the mMC3R, and caused a significant increase in food intake when injected intrathecally into male mice. Three compounds possessed sigmoidal dose-response inverse agonist curves at the mMC5R, while the remaining seven decreased cAMP production from basal levels at a concentration of 100 μM. These findings will add to the knowledge base toward the development of potent and selective probes to study the role of the melanocortin system in diseases of negative energy balance and can be useful in the design of molecular probes to examine the physiological functions of the mMC5R.
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Affiliation(s)
- Katlyn A. Fleming
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Mark D. Ericson
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Danielle N. Adank
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Mary M. Lunzer
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Stacey L. Wilber
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Carrie Haskell-Luevano
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
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8
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Ericson MD, Freeman KT, Schnell SM, Fleming KA, Haskell-Luevano C. Structure-Activity Relationship Studies on a Macrocyclic Agouti-Related Protein (AGRP) Scaffold Reveal Agouti Signaling Protein (ASP) Residue Substitutions Maintain Melanocortin-4 Receptor Antagonist Potency and Result in Inverse Agonist Pharmacology at the Melanocortin-5 Receptor. J Med Chem 2017; 60:8103-8114. [PMID: 28813605 DOI: 10.1021/acs.jmedchem.7b00856] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The melanocortin system consists of five reported receptors, agonists from the proopiomelanocortin gene transcript, and two antagonists, agouti-signaling protein (ASP) and agouti-related protein (AGRP). For both ASP and AGRP, the hypothesized Arg-Phe-Phe pharmacophores are on exposed β-hairpin loops. In this study, the Asn and Ala positions of a reported AGRP macrocyclic scaffold (c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-DPro]) were explored with 14-compound and 8-compound libraries, respectively, to generate more potent, selective melanocortin receptor antagonists. Substituting diaminopropionic acid (Dap), DDap, and His at the Asn position yielded potent MC4R ligands, while replacing Ala with Ser maintained MC4R potency. Since these substitutions correlate to ASP loop residues, an additional Phe to Ala substitution was synthesized and observed to maintain MC4R potency. Seventeen compounds also possessed inverse agonist activity at the MC5R, the first report of this pharmacology. These findings are useful in developing molecular probes to study negative energy balance conditions and unidentified functions of the MC5R.
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Affiliation(s)
- Mark D Ericson
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Katie T Freeman
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Sathya M Schnell
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Katlyn A Fleming
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry, University of Minnesota , 308 Harvard Street SE, Minneapolis, Minnesota 55455, United States
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9
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Doering SR, Freeman KT, Schnell SM, Haslach EM, Dirain M, Debevec G, Geer P, Santos RG, Giulianotti MA, Pinilla C, Appel JR, Speth RC, Houghten RA, Haskell-Luevano C. Discovery of Mixed Pharmacology Melanocortin-3 Agonists and Melanocortin-4 Receptor Tetrapeptide Antagonist Compounds (TACOs) Based on the Sequence Ac-Xaa 1-Arg-(pI)DPhe-Xaa 4-NH 2. J Med Chem 2017; 60:4342-4357. [PMID: 28453292 DOI: 10.1021/acs.jmedchem.7b00301] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The centrally expressed melanocortin-3 and -4 receptors (MC3R/MC4R) have been studied as possible targets for weight management therapies, with a preponderance of studies focusing on the MC4R. Herein, a novel tetrapeptide scaffold [Ac-Xaa1-Arg-(pI)DPhe-Xaa4-NH2] is reported. The scaffold was derived from results obtained from a MC3R mixture-based positional scanning campaign. From these results, a set of 48 tetrapeptides were designed and pharmacologically characterized at the mouse melanocortin-1, -3, -4, and -5 receptors. This resulted in the serendipitous discovery of nine compounds that were MC3R agonists (EC50 < 1000 nM) and MC4R antagonists (5.7 < pA2 < 7.8). The three most potent MC3R agonists, 18 [Ac-Arg-Arg-(pI)DPhe-Tic-NH2], 1 [Ac-His-Arg-(pI)DPhe-Tic-NH2], and 41 [Ac-Arg-Arg-(pI)DPhe-DNal(2')-NH2] were more potent (EC50 < 73 nM) than the melanocortin tetrapeptide Ac-His-DPhe-Arg-Trp-NH2. This template contains a sequentially reversed "Arg-(pI)DPhe" motif with respect to the classical "Phe-Arg" melanocortin signaling motif, which results in pharmacology that is first-in-class for the central melanocortin receptors.
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Affiliation(s)
- Skye R Doering
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Katie T Freeman
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Sathya M Schnell
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Erica M Haslach
- Department of Pharmacodynamics, University of Florida , Gainesville, Florida 32610, United States
| | - Marvin Dirain
- Department of Pharmacodynamics, University of Florida , Gainesville, Florida 32610, United States
| | - Ginamarie Debevec
- Torrey Pines Institute for Molecular Studies , Port St. Lucie, Florida 34987, United States
| | - Phaedra Geer
- Torrey Pines Institute for Molecular Studies , Port St. Lucie, Florida 34987, United States
| | - Radleigh G Santos
- Torrey Pines Institute for Molecular Studies , Port St. Lucie, Florida 34987, United States
| | - Marc A Giulianotti
- Torrey Pines Institute for Molecular Studies , Port St. Lucie, Florida 34987, United States
| | - Clemencia Pinilla
- Torrey Pines Institute for Molecular Studies , San Diego, California 92121, United States
| | - Jon R Appel
- Torrey Pines Institute for Molecular Studies , San Diego, California 92121, United States
| | - Robert C Speth
- College of Pharmacy, Nova Southeastern University , Fort Lauderdale, Florida 33328, United States.,Department of Pharmacology and Physiology, Georgetown University , Washington, D.C. 20057, United States
| | - Richard A Houghten
- Torrey Pines Institute for Molecular Studies , Port St. Lucie, Florida 34987, United States.,Torrey Pines Institute for Molecular Studies , San Diego, California 92121, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States.,Department of Pharmacodynamics, University of Florida , Gainesville, Florida 32610, United States
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10
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Gluckman TL, Mundy NI. The differential expression of MC1R regulators in dorsal and ventral quail plumages during embryogenesis: Implications for plumage pattern formation. PLoS One 2017; 12:e0174714. [PMID: 28355309 PMCID: PMC5371383 DOI: 10.1371/journal.pone.0174714] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 03/14/2017] [Indexed: 12/03/2022] Open
Abstract
Melanin pigmentation patterns are ubiquitous in animals and function in crypsis, physical protection, thermoregulation and signalling. In vertebrates, pigmentation patterns formed over large body regions as well as within appendages (hair/feathers) may be due to the differential distribution of pigment producing cells (melanocytes) and/or regulation of the melanin synthesis pathway. We took advantage of the pigmentation patterns of Japanese quail embryos (pale ventrum and patterned feathers dorsally) to explore the role of genes and their transcripts in regulating the function of the melanocortin-1-receptor (MC1R) via 1. activation: pro-opiomelanocortin (POMC), endoproteases prohormone convertase 1 (PC1) and 2 (PC2), and 2. inhibition—agouti signaling and agouti-related protein (ASIP and AGRP, respectively). Melanocytes are present in all feather follicles at both 8 and 12 days post-fertilisation (E8/E12), so differential deposition of melanocytes is not responsible for pigmentation patterns in embryonic quail. POMC transcripts expressed were a subset of those found in chicken and POMC expression within feather follicles was strong. PC1 was not expressed in feather follicles. PC2 was strongly expressed in all feather follicles at E12. ASIP transcript expression was variable and we report four novel ASIP transcripts. ASIP is strongly expressed in ventral feather follicles, but not dorsally. AGRP expression within feather follicles was weak. These results demonstrate that the pale-bellied quail phenotype probably involves inhibition of MC1R, as found previously. However, quail may require MC1R activation for eumelanogenesis in dorsal feathers which may have important implications for an understanding of colour pattern formation in vertebrates.
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Affiliation(s)
- Thanh-Lan Gluckman
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, United Kingdom
- Center for Interdisciplinary Research in Biology, Collège de France, Paris, France
- * E-mail:
| | - Nicholas I. Mundy
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, United Kingdom
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11
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Ericson MD, Freeman KT, Schnell SM, Haskell-Luevano C. A Macrocyclic Agouti-Related Protein/[Nle 4,DPhe 7]α-Melanocyte Stimulating Hormone Chimeric Scaffold Produces Subnanomolar Melanocortin Receptor Ligands. J Med Chem 2017; 60:805-813. [PMID: 28045525 DOI: 10.1021/acs.jmedchem.6b01707] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The melanocortin system consists of five receptor subtypes, endogenous agonists, and naturally occurring antagonists. These receptors and ligands have been implicated in numerous biological pathways including processes linked to obesity and food intake. Herein, a truncation structure-activity relationship study of chimeric agouti-related protein (AGRP)/[Nle4,DPhe7]α-melanocyte stimulating hormone (NDP-MSH) ligands is reported. The tetrapeptide His-DPhe-Arg-Trp or tripeptide DPhe-Arg-Trp replaced the Arg-Phe-Phe sequence in the AGRP active loop derivative c[Pro-Arg-Phe-Phe-Xxx-Ala-Phe-DPro], where Xxx was the native Asn of AGRP or a diaminopropionic (Dap) acid residue previously shown to increase antagonist potency at the mMC4R. The Phe, Ala, and Dap/Asn residues were successively removed to generate a 14-member library that was assayed for agonist activity at the mouse MC1R, MC3R, MC4R, and MC5R. Two compounds possessed nanomolar agonist potency at the mMC4R, c[Pro-His-DPhe-Arg-Trp-Asn-Ala-Phe-DPro] and c[Pro-His-DPhe-Arg-Trp-Dap-Ala-DPro], and may be further developed to generate novel melanocortin probes and ligands for understanding and treating obesity.
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Affiliation(s)
- Mark D Ericson
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Katie T Freeman
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Sathya M Schnell
- 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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12
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Ericson MD, Wilczynski A, Sorensen NB, Xiang Z, Haskell-Luevano C. Discovery of a β-Hairpin Octapeptide, c[Pro-Arg-Phe-Phe-Dap-Ala-Phe-DPro], Mimetic of Agouti-Related Protein(87-132) [AGRP(87-132)] with Equipotent Mouse Melanocortin-4 Receptor (mMC4R) Antagonist Pharmacology. J Med Chem 2015; 58:4638-47. [PMID: 25898270 DOI: 10.1021/acs.jmedchem.5b00184] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Agouti-related protein (AGRP) is a potent orexigenic peptide that antagonizes the melanocortin-3 and -4 receptors (MC3R and MC4R). While the C-terminal domain of AGRP, AGRP(87-132), is equipotent to the full-length peptide, further truncation decreases potency at the MC3R and MC4R. Herein, we report AGRP-derived peptides designed to mimic the active β-hairpin secondary structure that contains the hypothesized Arg-Phe-Phe pharmacophore. The most potent scaffold, c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-DPro], comprised the hexa-peptide β-hairpin loop from AGRP cyclized through a DPro-Pro motif. A 20 compound library was synthesized from this scaffold for further structure-activity relationship studies. The most potent peptide from this library was an asparagine to diaminopropionic acid substitution that possessed sub-nanomolar antagonist activity at the mMC4R and was greater than 160-fold selective for the mMC4R versus the mMC3R. The reported ligands may serve as probes to characterize the melanocortin receptors in vivo and leads in the development of novel therapeutics.
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Affiliation(s)
- Mark D Ericson
- †Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Andrzej Wilczynski
- ‡Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Nicholas B Sorensen
- ‡Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Zhimin Xiang
- ‡Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Carrie Haskell-Luevano
- †Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States.,‡Department of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
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13
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Hill TA, Shepherd NE, Diness F, Fairlie DP. Constraining cyclic peptides to mimic protein structure motifs. Angew Chem Int Ed Engl 2014; 53:13020-41. [PMID: 25287434 DOI: 10.1002/anie.201401058] [Citation(s) in RCA: 292] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 04/02/2013] [Indexed: 12/18/2022]
Abstract
Many proteins exert their biological activities through small exposed surface regions called epitopes that are folded peptides of well-defined three-dimensional structures. Short synthetic peptide sequences corresponding to these bioactive protein surfaces do not form thermodynamically stable protein-like structures in water. However, short peptides can be induced to fold into protein-like bioactive conformations (strands, helices, turns) by cyclization, in conjunction with the use of other molecular constraints, that helps to fine-tune three-dimensional structure. Such constrained cyclic peptides can have protein-like biological activities and potencies, enabling their uses as biological probes and leads to therapeutics, diagnostics and vaccines. This Review highlights examples of cyclic peptides that mimic three-dimensional structures of strand, turn or helical segments of peptides and proteins, and identifies some additional restraints incorporated into natural product cyclic peptides and synthetic macrocyclic peptidomimetics that refine peptide structure and confer biological properties.
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Affiliation(s)
- Timothy A Hill
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072 (Australia)
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14
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Hill TA, Shepherd NE, Diness F, Fairlie DP. Fixierung cyclischer Peptide: Mimetika von Proteinstrukturmotiven. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201401058] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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15
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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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16
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Eliasen R, Daly NL, Wulff BS, Andresen TL, Conde-Frieboes KW, Craik DJ. Design, synthesis, structural and functional characterization of novel melanocortin agonists based on the cyclotide kalata B1. J Biol Chem 2012; 287:40493-501. [PMID: 23012369 DOI: 10.1074/jbc.m112.395442] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Cyclotides are useful scaffolds to stabilize bioactive peptides. RESULTS Four melanocortin analogues of kalata B1 were synthesized. One is a selective MC4R agonist. CONCLUSION The analogues retain the native kalata B1 scaffold and introduce a designed pharmacological activity, validating cyclotides as protein engineering scaffolds. SIGNIFICANCE A novel type of melanocortin agonist has been developed, with potential as a drug lead for treating obesity. Obesity is an increasingly important global health problem that lacks current treatment options. The melanocortin receptor 4 (MC4R) is a target for obesity therapies because its activation triggers appetite suppression and increases energy expenditure. Cyclotides have been suggested as scaffolds for the insertion and stabilization of pharmaceutically active peptides. In this study, we explored the development of appetite-reducing peptides by synthesizing MC4R agonists based on the insertion of the His-Phe-Arg-Trp sequence into the cyclotide kalata B1. The ability of the analogues to fold similarly to kalata B1 but display MC4R activity were investigated. Four peptides were synthesized using t-butoxycarbonyl peptide chemistry with a C-terminal thioester to facilitate backbone cyclization. The structures of the peptides were found to be similar to kalata B1, evaluated by Hα NMR chemical shifts. KB1(GHFRWG;23-28) had a K(i) of 29 nm at the MC4R and was 107 or 314 times more selective over this receptor than MC1R or MC5R, respectively, and had no detectable binding to MC3R. The peptide had higher affinity for the MC4R than the endogenous agonist, α-melanocyte stimulation hormone, but it was less potent at the MC4R, with an EC(50) of 580 nm for activation of the MC4R. In conclusion, we synthesized melanocortin analogues of kalata B1 that preserve the structural scaffold and display receptor binding and functional activity. KB1(GHFRWG;23-28) is potent and selective for the MC4R. This compound validates the use of cyclotides as scaffolds and has the potential to be a new lead for the treatment of obesity.
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17
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Madonna ME, Schurdak J, Yang YK, Benoit S, Millhauser GL. Agouti-related protein segments outside of the receptor binding core are required for enhanced short- and long-term feeding stimulation. ACS Chem Biol 2012; 7:395-402. [PMID: 22129136 DOI: 10.1021/cb2003412] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The agouti-related protein (AgRP) plays a central role in energy balance by reducing signaling through the hypothalamic melanocortin receptors (McRs) 3 and 4, in turn stimulating feeding and decreasing energy expenditure. Mature AgRP(83-132), produced by endoproteolytic processing, contains a central region that folds as an inhibitor cystine knot (ICK) stabilized by a network of disulfide bonds; this domain alone carries the molecular features for high affinity McR binding and inverse agonism. Outside of the ICK domain are two polypeptide segments, an N-terminal extension and a C-terminal loop, both completely conserved but of unknown function. Here we examine the physiological roles of these non-ICK segments by developing a panel of modified AgRPs that were administered to rats through intracerebroventricular (ICV) injection. Analysis of food consumption demonstrates that basic (positively charged) residues are essential for potent short- and long-term AgRP stimulated feeding. Moreover, we demonstrate an approximate linear relationship between protein charge density and 24 h food intake. Next, we developed artificial AgRP(83-132) analogues with increased positive charge and found that these species were substantially more potent than wild type. A single dose of one protein, designated AgRP-4K, results in enhanced feeding for well over a week and weight gain that is nearly double that of AgRP(83-132). These studies suggest new strategies for the development of potent orexigenic species and may serve as leads for the development of therapeutics for treating wasting conditions such as cachexia.
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Affiliation(s)
- Michael E. Madonna
- Department of Chemistry and
Biochemistry, University of California,
Santa Cruz, California 95064, United States
| | - Jennifer Schurdak
- Department of Psychiatry, University of Cincinnati, Cincinnati, Ohio 45237, United
States
| | - Ying-kui Yang
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama
35205, United States
| | - Stephen Benoit
- Department of Psychiatry, University of Cincinnati, Cincinnati, Ohio 45237, United
States
| | - Glenn L. Millhauser
- Department of Chemistry and
Biochemistry, University of California,
Santa Cruz, California 95064, United States
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18
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Fanelli F, De Benedetti PG. Update 1 of: computational modeling approaches to structure-function analysis of G protein-coupled receptors. Chem Rev 2011; 111:PR438-535. [PMID: 22165845 DOI: 10.1021/cr100437t] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Francesca Fanelli
- Dulbecco Telethon Institute, University of Modena and Reggio Emilia, via Campi 183, 41125 Modena, Italy.
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19
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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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20
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Abstract
AbstractThe melanocortin 4 receptor (MC4R) is involved in the regulation of energy homeostasis and is known as one of the major hypothalamic regulators of food intake. Several studies have shown that replacement of aspartic acid at position 126 of the MC4R abolishes the ligand binding. We used the modified yeast Saccharomyces cerevisiae strain MMY28 to functionally express the MC4R and characterise the importance of this amino acid for ligand based activation of the receptor. The efficiency of the functional expression system was estimated by activation with αMSH, ACTH and THIQ and compared with cAMP response in mammalian cells. We generated the library of MC4R mutants randomised at the amino acid position 126. Recombinant MC4R clones were screened for the αMSH induced activity in yeast. From 9 different amino acids obtained only the natural aspartic acid displayed the ligand dependent activity of MC4R. The MC4R variants with glutamic acid and leucine at position 126, however, displayed higher background activity than other amino acid substitutions. The results suggest that the yeast expression system is suitable for screening of the MC4R receptor ligands and that the substitution of aspartic acid at position 126 of MC4R by different amino acids functionally inactivates the receptor.
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21
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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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22
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Singh A, Wilczynski A, Holder JR, Witek RM, Dirain ML, Xiang Z, Edison AS, Haskell-Luevano C. Incorporation of a bioactive reverse-turn heterocycle into a peptide template using solid-phase synthesis to probe melanocortin receptor selectivity and ligand conformations by 2D 1H NMR. J Med Chem 2011; 54:1379-90. [PMID: 21306168 DOI: 10.1021/jm101425m] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
By use of a solid-phase synthetic approach, a bioactive reverse turn heterocycle was incorporated into a cyclic peptide template to probe melanocortin receptor potency and ligand structural conformations. The five melanocortin receptor isoforms (MC1R-MC5R) are G-protein-coupled receptors (GPCRs) that are regulated by endogenous agonists and antagonists. This pathway is involved in pigmentation, weight, and energy homeostasis. Herein, we report novel analogues of the chimeric AGRP-melanocortin peptide template integrated with a small molecule moiety to probe the structural and functional consequences of the core His-Phe-Arg-Trp peptide domain using a reverse-turn heterocycle. A series of six compounds are reported that result in inactive to full agonists with nanomolar potency. Biophysical structural analysis [2D (1)H NMR and computer-assisted molecular modeling (CAMM)] were performed on selected analogues, resulting in the identification that these peptide-small molecule hybrids possessed increased flexibility and fewer discrete conformational families compared to the reference peptide and result in a novel template for further structure-function studies.
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Affiliation(s)
- Anamika Singh
- Department of Pharmacodynamics, University of Florida, Gainesville, Florida 32610, United States
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23
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Viso A, Fernández de la Pradilla R, Tortosa M, García A, Flores A. Update 1 of: α,β-Diamino Acids: Biological Significance and Synthetic Approaches. Chem Rev 2011; 111:PR1-42. [DOI: 10.1021/cr100127y] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Alma Viso
- Instituto de Química Orgánica, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain
| | | | - Mariola Tortosa
- Instituto de Química Orgánica, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain
| | - Ana García
- Instituto de Química Orgánica, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain
| | - Aida Flores
- Instituto de Química Orgánica, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain
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24
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Irani BG, Xiang Z, Yarandi HN, Holder JR, Moore MC, Bauzo RM, Proneth B, Shaw AM, Millard WJ, Chambers JB, Benoit SC, Clegg DJ, Haskell-Luevano C. Implication of the melanocortin-3 receptor in the regulation of food intake. Eur J Pharmacol 2011; 660:80-7. [PMID: 21199647 DOI: 10.1016/j.ejphar.2010.10.101] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2010] [Revised: 09/28/2010] [Accepted: 10/12/2010] [Indexed: 10/18/2022]
Abstract
The melanocortin system is well recognized to be involved in the regulation of food intake, body weight, and energy homeostasis. To probe the role of the MC(3) in the regulation of food intake, JRH322-18 a mixed MC(3) partial agonist/antagonist and MC(4) agonist tetrapeptide was examined in wild type (WT) and melanocortin 4 receptor (MC(4)) knockout mice and shown to reduce food intake in both models. In the wild type mice, 2.0 nmol of JRH322-18 statistically reduced food intake 4h post icv treatment into satiated nocturnally feeding wild type mice. The same dose in the MC(4)KO mice significantly reduced cumulative food intake 24h post treatment. Conditioned taste aversion as well as activity studies supports that the decreased food intake was not due to visceral illness. Since these studies resulted in loss-of-function results, the SHU9119 and agouti-related protein (AGRP) melanocortin receptor antagonists were administered to wild type as well as the MC(3) and MC(4) knockout mice in anticipation of gain-of-function results. The SHU9119 ligand produced an increase in food intake in the wild type mice as anticipated, however no effect was observed in the MC(3) and MC(4) knockout mice as compared to the saline control. The AGRP ligand however, produced a significant increase in food intake in the wild type as well as the MC(3) and MC(4) knockout mice and it had a prolonged affect for several days. These data support the hypothesis that the MC(3) plays a subtle role in the regulation of food intake, however the mechanism by which this is occurring remains to be determined.
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Affiliation(s)
- Boman G Irani
- Department of Pharmacodynamics, University of Florida, PO Box 100487, Gainesville, FL-32610, United States
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25
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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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Patel MP, Cribb Fabersunne CS, Yang YK, Kaelin CB, Barsh GS, Millhauser GL. Loop-swapped chimeras of the agouti-related protein and the agouti signaling protein identify contacts required for melanocortin 1 receptor selectivity and antagonism. J Mol Biol 2010; 404:45-55. [PMID: 20831872 DOI: 10.1016/j.jmb.2010.08.054] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 08/12/2010] [Accepted: 08/30/2010] [Indexed: 11/29/2022]
Abstract
Agouti-related protein (AgRP) and agouti signaling protein (ASIP) are homologs that play critical roles in energy balance and pigmentation, respectively, by functioning as antagonistic ligands at their cognate melanocortin receptors. Signaling specificity is mediated in part through receptor binding selectivity brought about by alterations in the cysteine-rich carboxy-terminal domains of the ligands. AgRP binds with high affinity to the melanocortin 3 receptor and the melanocortin 4 receptor, but not to the melanocortin 1 receptor (MC1R), whereas ASIP binds with high affinity to all three receptors. This work explores the structural basis for receptor selectivity by studying chimeric proteins developed by interchanging loops between the cysteine-rich domain of ASIP and the cysteine-rich domain of AgRP. Binding data demonstrate that melanocortin 4 receptor responds to all chimeras and is therefore highly tolerant of gross loop changes. By contrast, MC1R responds primarily to those chimeras with a sequence close to that of wild-type ASIP. Further analysis of binding and functional data suggests that the ASIP C-terminal loop (a six-amino-acid segment closed by the final disulfide bond) is essential for high-affinity MC1R binding and inverse agonism. Comparison with previously published molecular models suggests that this loop makes contact with the first extracellular loop of MC1R through a series of key hydrophobic interactions.
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Affiliation(s)
- Mira P Patel
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064, USA
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27
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Xiang Z, Proneth B, Dirain ML, Litherland SA, Haskell-Luevano C. Pharmacological characterization of 30 human melanocortin-4 receptor polymorphisms with the endogenous proopiomelanocortin-derived agonists, synthetic agonists, and the endogenous agouti-related protein antagonist. Biochemistry 2010; 49:4583-600. [PMID: 20462274 DOI: 10.1021/bi100068u] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The melanocortin-4 receptor (MC4R) is a G-protein-coupled receptor (GPCR) that is expressed in the central nervous system and has a role in regulating feeding behavior, obesity, energy homeostasis, male erectile response, and blood pressure. Since the report of the MC4R knockout mouse in 1997, the field has been searching for links between this genetic biomarker and human obesity and type 2 diabetes. More then 80 single nucleotide polymorphisms (SNPs) have been identified from human patients, both obese and nonobese controls. Many significant studies have been performed examining the pharmacological characteristics of these hMC4R SNPs in attempts to identify a molecular defects/insights that might link a genetic factor to the obese phenotype observed in patients possessing these mutations. Our laboratory has previously reported the pharmacological characterization of 40 of these polymorphic hMC4 receptors with multiple endogenous and synthetic ligands. The goal of the current study is to perform a similar comprehensive side-by-side characterization of 30 additional human hMC4R with single nucleotide polymorphisms using multiple endogenous agonists [alpha-, beta-, and gamma(2)-melanocyte stimulating hormones (MSH) and adrenocorticotropin (ACTH)], the antagonist agouti-related protein hAGRP(87-132), and synthetic agonists [NDP-MSH, MTII, and the tetrapeptide Ac-His-dPhe-Arg-Trp-NH(2) (JRH887-9)]. These in vitro data, in some cases, provide a putative molecular link between dysfunctional hMC4R's and human obesity. These 30 hMC4R SNPs include R7H, R18H, R18L, S36Y, P48S, V50M, F51L, E61K, I69T, D90N, S94R, G98R, I121T, A154D, Y157S, W174C, G181D, F202L, A219 V, I226T, G231S, G238D, N240S, C271R, S295P, P299L, E308K, I317V, L325F, and 750DelGA. All but the N240S hMC4R were identified in obese patients. Additionally, we have characterized a double I102T/V103I hMC4R. In addition to the pharmacological characterization, the hMC4R variants were evaluated for cell surface expression by flow cytometry. The F51L, I69T, and A219V hMC4Rs possessed full agonist activity and significantly decreased endogenous agonist ligand potency. At the E61K, D90N, Y157S, and C271R hMC4Rs, all agonist ligands examined were only partially efficacious in generating a maximal signaling response (partial agonists) and possessed significantly decreased endogenous agonist ligand potency. Only the A219V, G238D, and S295P hMC4Rs possessed significantly decreased AGRP(87-132) antagonist potency. These data provide new information for use in GPCR computational development as well as insights into MC4R structure ad function.
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Affiliation(s)
- Zhimin Xiang
- Department of Pharmacodynamics, University of Florida, Gainesville, Florida 32610, USA
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28
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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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29
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Functional analysis of melanocortin-4-receptor mutants identified in severely obese subjects living in Southern Italy. Gene 2010; 457:35-41. [PMID: 20214954 DOI: 10.1016/j.gene.2010.03.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 01/27/2010] [Accepted: 03/01/2010] [Indexed: 11/23/2022]
Abstract
The melanocortin-4 receptor (MC4R) is involved in regulating energy homeostasis; mutations in this gene have been associated with 1-5% of early-onset human obesity. The aim of this study was to functionally characterize MC4R mutations identified in morbidly obese subjects living in Southern Italy. We studied their ligand binding, signaling pathway and subcellular localization. As expected, mutants Q43X and S19fsX51, which produce truncated forms of receptor, were devoid of activity. The activity of mutants W174C and A175T were very different even though the mutations are adjacent and are in the same transmembrane helix (TMH). In fact, the production and expression of mutant A175T on the plasma-membrane (PM) was similar to that of the wild-type (wt) receptor and the mutant retained 70% of wt receptor activity; on the contrary, the production of W174C mutant in the cytoplasm was similar to that of the wt receptor and mutant A175T but was only barely detectable on the PM and was devoid of activity. Confocal microscopy showed that W174C remained entrapped in the endoplasmic reticulum (ER) of the cells. Structural analysis showed that substitution of Trp174, located in the middle of TMH4 and 100% conserved in all known MC4Rs, with Cys could impair the relative orientation of TMH2 and TMH4 thereby affecting the overall protein architecture. Furthermore, co-expression studies showed that mutant A175T but not W174C had a dominant negative effect on the wt receptor activity.
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30
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Structure-Activity Relationships (SAR) of Melanocortin and Agouti-Related (AGRP) Peptides. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 681:1-18. [DOI: 10.1007/978-1-4419-6354-3_1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
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31
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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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32
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Shimizu H, Oh-I S, Hashimoto K, Nakata M, Yamamoto S, Yoshida N, Eguchi H, Kato I, Inoue K, Satoh T, Okada S, Yamada M, Yada T, Mori M. Peripheral administration of nesfatin-1 reduces food intake in mice: the leptin-independent mechanism. Endocrinology 2009; 150:662-71. [PMID: 19176321 DOI: 10.1210/en.2008-0598] [Citation(s) in RCA: 232] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Nesfatin-1 is a novel satiety molecule in the hypothalamus and is also present in peripheral tissues. Here we sought to identify the active segment of nesfatin-1 and to determine the mechanisms of its action after peripheral administration in mice. Intraperitoneal injection of nesfatin-1 suppressed food intake in a dose-dependent manner. Nesfatin-1 has three distinct segments; we tested the effect of each segment on food intake. Injection of the midsegment decreased food intake under leptin-resistant conditions such as db/db mice and mice fed a high-fat diet. After injection of the midsegment, expression of c-Fos was significantly activated in the brainstem nucleus tractus solitarius (NTS) but not in the hypothalamic arcuate nucleus; the nicotinic cholinergic pathway to the NTS contributed to midsegment-induced anorexia. Midsegment injection significantly increased expression of proopiomelanocortin and cocaine- and amphetamine-regulated transcript genes in the NTS but not in the arcuate nucleus. Investigation of mutant midsegments demonstrated that a region with amino acid sequence similarity to the active site of agouti-related peptide was indispensable for anorexigenic induction. Our findings indicate that the midsegment of nesfatin-1 causes anorexia, possibly by activating POMC and CART neurons in the NTS via a leptin-independent mechanism after peripheral stimulation.
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Affiliation(s)
- H Shimizu
- Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi, Japan.
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33
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Haskell-Luevano C, Xiang Z, Wilczynski AM, Haskell KR, Andreasen AM, Litherland SA, Millard WJ, Pogozheva ID, Mosberg HI, Sorenson NB. Discovery of a Ligand that Compensates for Decreased Endogenous Agonist Potency of Melanocortin-4 Receptor Polymorphisms Identified in Obese Humans. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2009; 611:509-10. [DOI: 10.1007/978-0-387-73657-0_221] [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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34
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Joseph CG, Wilson KR, Wood MS, Sorenson NB, Phan DV, Xiang Z, Witek RM, Haskell-Luevano C. The 1,4-Benzodiazepine-2,5-dione Small Molecule Template Results in Melanocortin Receptor Agonists with Nanomolar Potencies. J Med Chem 2008; 51:1423-31. [DOI: 10.1021/jm701303z] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christine G. Joseph
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Krista R. Wilson
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Michael S. Wood
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Nicholas B. Sorenson
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Dong V. Phan
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Zhimin Xiang
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Rachel M. Witek
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610
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35
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Nozawa D, Okubo T, Chaki S, Okuyama S, Nakazato A. Identification of arginine analogues as antagonists and agonists for the melanocortin-4 receptor. Chem Pharm Bull (Tokyo) 2007; 55:1232-9. [PMID: 17666851 DOI: 10.1248/cpb.55.1232] [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] [Indexed: 11/22/2022]
Abstract
In the present study, conducted to explore potent and small molecular melanocortin-4 (MC4) receptor ligands, we found that tripeptide 3a, containing a D-Phe-Arg-2-Nal (Nal; naphthylalanine) sequence, exhibited a moderate affinity for the MC4 receptor. Structural optimization led to the identification of a compound with a high affinity for the MC4 receptor, namely, tripeptide 3e, which showed a 70-fold higher affinity for the MC4 receptor than the lead compound 3a. Moreover, in an effort to further reduce the peptidic characters of tripeptide 3e, we found that dipeptide 3g exhibited a relatively high affinity for the MC4 receptor. Furthermore, in these analogues, the substituted position (1' vs. 2') of the naphthyl ring of Nal residue at position 7 was found to be important for the differentiation of agonist and antagonist activity. The synthesis and structure-activity relationships of the arginine analogues as MC4 receptor ligands were described in this paper.
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Affiliation(s)
- Dai Nozawa
- Medicinal Research Laboratories, Taisho Pharmaceutical Co., Ltd., Saitama, Japan.
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36
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Jackson PJ, Douglas NR, Chai B, Binkley J, Sidow A, Barsh GS, Millhauser GL. Structural and molecular evolutionary analysis of Agouti and Agouti-related proteins. ACTA ACUST UNITED AC 2007; 13:1297-305. [PMID: 17185225 PMCID: PMC2907901 DOI: 10.1016/j.chembiol.2006.10.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 09/20/2006] [Accepted: 10/11/2006] [Indexed: 10/23/2022]
Abstract
Agouti (ASIP) and Agouti-related protein (AgRP) are endogenous antagonists of melanocortin receptors that play critical roles in the regulation of pigmentation and energy balance, respectively, and which arose from a common ancestral gene early in vertebrate evolution. The N-terminal domain of ASIP facilitates antagonism by binding to an accessory receptor, but here we show that the N-terminal domain of AgRP has the opposite effect and acts as a prodomain that negatively regulates antagonist function. Computational analysis reveals similar patterns of evolutionary constraint in the ASIP and AgRP C-terminal domains, but fundamental differences between the N-terminal domains. These studies shed light on the relationships between regulation of pigmentation and body weight, and they illustrate how evolutionary structure function analysis can reveal both unique and common mechanisms of action for paralogous gene products.
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Affiliation(s)
- Pilgrim J. Jackson
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064
| | - Nick R. Douglas
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064
| | - Biaoxin Chai
- Department of Surgery, University of Michigan Medical Center, Ann Arbor, Michigan 48109-0682
| | - Jonathan Binkley
- Department of Pathology, Stanford University Medical Center, Stanford, California 94305
| | - Arend Sidow
- Department of Genetics, Stanford University Medical Center, Stanford, California 94305
- Department of Pathology, Stanford University Medical Center, Stanford, California 94305
| | - Gregory S. Barsh
- Department of Genetics, Stanford University Medical Center, Stanford, California 94305
- Department of Pediatrics, Stanford University Medical Center, Stanford, California 94305
- Correspondence: (G.S.B.), (G.L.M.)
| | - Glenn L. Millhauser
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064
- Correspondence: (G.S.B.), (G.L.M.)
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37
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Nozawa D, Okubo T, Ishii T, Kakinuma H, Chaki S, Okuyama S, Nakazato A. Structure–activity relationships of novel piperazines as antagonists for the melanocortin-4 receptor. Bioorg Med Chem 2007; 15:1989-2005. [PMID: 17234422 DOI: 10.1016/j.bmc.2006.12.039] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2006] [Revised: 12/22/2006] [Accepted: 12/23/2006] [Indexed: 10/23/2022]
Abstract
During the investigation of antagonists for the MC4 receptor, we found that 10ab having a naphthyl group showed almost the same binding affinity for the MC4 receptor as that of the lead compound 1 with a benzoyl group. We also developed a new type of compounds, namely, bis-piperazines, and found that the bis-piperazines 10 exhibited a high affinity for the MC4 receptor. In particular, (-)-10bg exhibited the highest affinity for the MC4 receptor with an IC50 value of 8.13nM. In this paper, we present the design, synthesis, and structure-activity relationships of the novel bis-piperazines as MC4 receptor antagonists.
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Affiliation(s)
- Dai Nozawa
- Medicinal Research Laboratories, Taisho Pharmaceutical Co., Ltd, 1-403 Yoshino-cho, Kita-ku, Saitama, Saitama 331-9530, Japan.
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38
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Martinelli A, Tuccinardi T. An overview of recent developments in GPCR modelling: methods and validation. Expert Opin Drug Discov 2006; 1:459-76. [DOI: 10.1517/17460441.1.5.459] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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39
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Pontillo J, Tran JA, White NS, Arellano M, Fleck BA, Marinkovic D, Tucci FC, Saunders J, Foster AC, Chen C. Structure–activity relationship studies on a series of cyclohexylpiperazines bearing a phanylacetamide as ligands of the human melanocortin-4 receptor. Bioorg Med Chem Lett 2005; 15:5237-40. [PMID: 16183282 DOI: 10.1016/j.bmcl.2005.08.061] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2005] [Revised: 08/17/2005] [Accepted: 08/17/2005] [Indexed: 10/25/2022]
Abstract
Synthesis and structure-activity relationship studies of a series of cyclohexylpiperazines bearing an amide side chain as ligands of the MC4 receptor are discussed. Compounds such as 11i from this series are potent agonists (EC(50)=33nM, IA=96%).
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Affiliation(s)
- Joseph Pontillo
- Department of Medicinal Chemistry, Neurocrine Biosciences Inc., 12790 El Camino Real, San Diego, CA 92130, USA
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40
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Jackson PJ, Yu B, Hunrichs B, Thompson DA, Chai B, Gantz I, Millhauser GL. Chimeras of the agouti-related protein: insights into agonist and antagonist selectivity of melanocortin receptors. Peptides 2005; 26:1978-87. [PMID: 16009463 DOI: 10.1016/j.peptides.2004.12.036] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Accepted: 12/12/2004] [Indexed: 11/29/2022]
Abstract
The specific melanocortin receptors, MC3R and MC4R, are directly linked to metabolism and body weight control. These receptors are activated by the peptide hormone alpha-MSH and antagonized by the agouti-related protein (AGRP). Whereas alpha-MSH acts broadly on most members of the MCR family (with the exception of MC2R), AGRP is highly specific for only MC3R and MC4R. AGRP is a complex ligand of approximately 100 amino acids. Within AGRP, MCR recognition and antagonism is localized to a 34 residue, cysteine-rich domain that adopts an inhibitor cystine knot (ICK) fold. An oxidatively folded peptide corresponding to this domain, referred to as mini-AGRP, exhibits full antagonist function and selectivity for MC3R and MC4R. Here we investigate a series of chimera proteins based on the mini-AGRP scaffold. Amino acid sequences derived from peptide agonists are grafted into the mini-AGRP active loop, implicated in receptor recognition, with the goal of producing ICK based agonists specific for MC3R and MC4R. Several constructs indeed exhibited potent agonist activity; however, with all chimeras, receptor selectivity is significantly altered. Pharmacologic data indicate that the chimeras do not interact with MC receptors through native AGRP like contacts. A model to explain the data suggest that there is only partial overlap of the agonist versus antagonist binding surfaces within MC receptors. Moreover, accessibility to the binding pocket is highly receptor specific with MC3R being the least tolerant of ligand alterations.
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Affiliation(s)
- Pilgrim J Jackson
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064, USA
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41
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Fanelli F, De Benedetti PG. Computational Modeling Approaches to Structure−Function Analysis of G Protein-Coupled Receptors. Chem Rev 2005; 105:3297-351. [PMID: 16159154 DOI: 10.1021/cr000095n] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Francesca Fanelli
- Dulbecco Telethon Institute and Department of Chemistry, University of Modena and Reggio Emilia, via Campi 183, 41100 Modena, Italy.
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42
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Viso A, Fernández de la Pradilla R, García A, Flores A. α,β-Diamino Acids: Biological Significance and Synthetic Approaches. Chem Rev 2005; 105:3167-96. [PMID: 16092828 DOI: 10.1021/cr0406561] [Citation(s) in RCA: 239] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alma Viso
- Instituto de Química Orgánica, CSIC, Juan de la Cierva 3, E-28006 Madrid, Spain.
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Cho MK, Lee CJ, Lee CH, Li SZ, Lim SK, Baik JH, Lee W. Structure and function of the potent cyclic and linear melanocortin analogues. J Struct Biol 2005; 150:300-8. [PMID: 15890278 DOI: 10.1016/j.jsb.2005.03.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2004] [Revised: 03/14/2005] [Accepted: 03/15/2005] [Indexed: 11/30/2022]
Abstract
The MC3R and MC4R proteins comprise two melanocortin receptor subtypes that are involved in obesity, with each protein displaying a unique mechanism of action. To enable the design of a selective drug candidate, the solution structures of four peptidyl analogues of the melanocyte stimulating hormones, NDP-MSH, NDP-MSH(4-10) and two cyclic forms ([C5,C10]NDP-MSH(5-10), [C5,C10]NDP-MSH(5-11)), were characterized by two-dimensional nuclear magnetic resonance (NMR) spectroscopy and simulated annealing calculations. Using data from c-AMP assays in combination with structural analysis of melanocortin receptor/ligand models, we conclude that a lysine residue at the C-terminus of the His-Phe-Arg-Trp core sequence of melanocortin hormone is an important determinant for receptor selectivity in the both cyclic and linear MSH analogues. Our results suggest that side-chain orientation and charge-charge interactions with the ligand molecule play critical roles in receptor selectivity, whereas the overall backbone conformation or turn type contributes mainly to receptor binding.
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Affiliation(s)
- Min-Kyu Cho
- Department of Biochemistry, College of Science, Yonsei University, Seoul 120-749, Republic of Korea
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McNulty JC, Jackson PJ, Thompson DA, Chai B, Gantz I, Barsh GS, Dawson PE, Millhauser GL. Structures of the agouti signaling protein. J Mol Biol 2005; 346:1059-70. [PMID: 15701517 DOI: 10.1016/j.jmb.2004.12.030] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Revised: 12/09/2004] [Accepted: 12/14/2004] [Indexed: 10/26/2022]
Abstract
Expression of the agouti signaling protein (ASIP) during hair growth produces the red/yellow pigment pheomelanin. ASIP, and its neuropeptide homolog the agouti-related protein (AgRP) involved in energy balance, are novel, paracrine signaling molecules that act as inverse agonists at distinct subsets of melanocortin receptors. Ubiquitous ASIP expression in mice gives rise to a pleiotropic phenotype characterized by a uniform yellow coat color, obesity, overgrowth, and metabolic derangements similar to type II diabetes in humans. Here we report the synthesis and NMR structure of ASIP's active, cysteine-rich, C-terminal domain. ASIP adopts the inhibitor cystine knot fold and, along with AgRP, are the only known mammalian proteins in this structure class. Moreover, ASIP populates two distinct conformers resulting from a cis peptide bond at Pro102-Pro103 and a coexistence of cis/trans isomers of Ala104-Pro105. Pharmacologic studies of Pro-->Ala mutants demonstrate that the minor conformation with two cis peptide bonds is responsible for activity at all MCRs. The loop containing the heterogeneous Ala-Pro peptide bond is conserved in mammals, and suggests that ASIP is either trapped by evolution in this unusual configuration or possesses function outside of strict MCR antagonism.
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Affiliation(s)
- Joseph C McNulty
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, CA 95064, USA
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Wilczynski AM, Joseph CG, Haskell-Luevano C. Current trends in the structure—activity relationship studies of the endogenous agouti-related protein (AGRP) melanocortin receptor antagonist. Med Res Rev 2005; 25:545-56. [PMID: 16044415 DOI: 10.1002/med.20037] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Agouti-related protein (AGRP) is an endogenous antagonist of the melanocortin-3 and -4 (MC3R and MC4) G-protein coupled receptors. The 87-132 amino acid C-terminal domain of hAGRP possesses five disulfide bridges and a well-defined three-dimensional structure that displays full biological activity as compared to the full-length protein. Based on the NMR structure of the C-terminal AGRP(87-132), a novel mini-protein, referred to as "Mini-AGRP" was designed that exhibited receptor binding affinity and antagonism similar to that of the parent hAGRP(87-132) protein. It was demonstrated that this new-engineered protein autonomously folds to the inhibitor cystine knot (ICK) motif. As this AGRP is a novel mammalian protein involved in energy homeostasis and possibly other physiological functions remaining to be identified, structure-function studies are starting to emerge toward the understanding of how this unique protein putatively interacts with the melanocortin receptors with the objective of designing potential therapeutic agents for in vivo physiological studies. This article summarizes the progress to date of AGRP-based structure-activity relationships and putative ligand-receptor interactions.
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Affiliation(s)
- Andrzej M Wilczynski
- Department of Medicinal Chemistry, University of Florida, Gainesville, FL 32610, USA
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Haskell-Luevano C, Todorovic A, Gridley K, Sorenson N, Irani B, Xiang Z. The melanocortin pathway: effects of voluntary exercise on the melanocortin-4 receptor knockout mice and ACTH(1-24) ligand structure activity relationships at the melanocortin-2 receptor. Endocr Res 2004; 30:591-7. [PMID: 15666796 DOI: 10.1081/erc-200043759] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The melanocortin pathway consists of endogenous agonists, antagonists, G-protein coupled receptors, and ancillary proteins that mediate the function of the endogenous antagonists. The melanocortin-4 receptor (MC4R) is involved in the regulation of obesity and the melanocortin-2 receptor (MC2R) is involved in the regulation of steroidogenesis. Herein, we present the effects of voluntary exercise on the MC4R knockout mice in terms of bypassing the morbid obesity and hyperphagia phenotypes associated with this genetic obesity model. Additionally, a systematic truncation study of the adrenocorticotropin hormone (ACTH 1-24) has been performed and characterized at the cloned MC2R.
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Affiliation(s)
- C Haskell-Luevano
- Department of Medicinal Chemistry, University of Florida, PO Box 100485, Gainesville, FL 32610, USA.
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