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Yuan XC, Tao YX. Ligands for Melanocortin Receptors: Beyond Melanocyte-Stimulating Hormones and Adrenocorticotropin. Biomolecules 2022; 12:biom12101407. [PMID: 36291616 PMCID: PMC9599618 DOI: 10.3390/biom12101407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/25/2022] [Accepted: 09/28/2022] [Indexed: 11/16/2022] Open
Abstract
The discovery of melanocortins in 1916 has resulted in more than 100 years of research focused on these peptides. Extensive studies have elucidated well-established functions of melanocortins mediated by cell surface receptors, including MSHR (melanocyte-stimulating hormone receptor) and ACTHR (adrenocorticotropin receptor). Subsequently, three additional melanocortin receptors (MCRs) were identified. Among these five MCRs, MC3R and MC4R are expressed primarily in the central nervous system, and are therefore referred to as the neural MCRs. Since the central melanocortin system plays important roles in regulating energy homeostasis, targeting neural MCRs is emerging as a therapeutic approach for treating metabolic conditions such as obesity and cachexia. Early efforts modifying endogenous ligands resulted in the development of many potent and selective ligands. This review focuses on the ligands for neural MCRs, including classical ligands (MSH and agouti-related peptide), nonclassical ligands (lipocalin 2, β-defensin, small molecules, and pharmacoperones), and clinically approved ligands (ACTH, setmelanotide, bremelanotide, and several repurposed drugs).
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Affiliation(s)
- Xiao-Chen Yuan
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230061, China
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL 36849, USA
- Correspondence:
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2
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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: 98] [Impact Index Per Article: 32.7] [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, Lensing CJ, Fleming KA, Schlasner KN, Doering SR, Haskell-Luevano C. Bench-top to clinical therapies: A review of melanocortin ligands from 1954 to 2016. Biochim Biophys Acta Mol Basis Dis 2017; 1863:2414-2435. [PMID: 28363699 PMCID: PMC5600687 DOI: 10.1016/j.bbadis.2017.03.020] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/21/2017] [Accepted: 03/27/2017] [Indexed: 10/19/2022]
Abstract
The discovery of the endogenous melanocortin agonists in the 1950s have resulted in sixty years of melanocortin ligand research. Early efforts involved truncations or select modifications of the naturally occurring agonists leading to the development of many potent and selective ligands. With the identification and cloning of the five known melanocortin receptors, many ligands were improved upon through bench-top in vitro assays. Optimization of select properties resulted in ligands adopted as clinical candidates. A summary of every melanocortin ligand is outside the scope of this review. Instead, this review will focus on the following topics: classic melanocortin ligands, selective ligands, small molecule (non-peptide) ligands, ligands with sex-specific effects, bivalent and multivalent ligands, and ligands advanced to clinical trials. Each topic area will be summarized with current references to update the melanocortin field on recent progress. This article is part of a Special Issue entitled: Melanocortin Receptors - edited by Ya-Xiong Tao.
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Affiliation(s)
- Mark D Ericson
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Cody J Lensing
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Katlyn A Fleming
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Katherine N Schlasner
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Skye R Doering
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
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4
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Møller CL, Pedersen SB, Richelsen B, Conde-Frieboes KW, Raun K, Grove KL, Wulff BS. Melanocortin agonists stimulate lipolysis in human adipose tissue explants but not in adipocytes. BMC Res Notes 2015; 8:559. [PMID: 26459134 PMCID: PMC4604100 DOI: 10.1186/s13104-015-1539-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2015] [Accepted: 10/02/2015] [Indexed: 01/12/2023] Open
Abstract
Background The central melanocortin system is broadly involved in the regulation of mammalian nutrient utilization. However, the function of melanocortin receptors (MCRs) expressed directly in peripheral metabolic tissues is still unclear. The objective of this study was to investigate the lipolytic capacity of MC1-5R in differentiated adipocytes versus intact white adipose tissue. Results Non-selective MCR agonist α-MSH, MC5R-selective agonist PG-901 and MC4R-selective agonist LY2112688 significantly stimulated lipolysis in intact white adipose tissue, whereas stimulation of MCRs in differentiated adipocytes failed to do so. The lipolytic response of MC5R was decreased in intact human white adipose tissue when co-treating with β-adrenergic antagonist propranolol, suggesting that the effect may be dependent on neuronal innervation via noradrenalin release. Conclusion When developing an anti-obesity therapeutic drug with selective MC4R/MC5R properties, effects on lipolysis in white adipose tissue may be physiologically relevant.
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Affiliation(s)
- Cathrine Laustrup Møller
- Diabetes and Obesity Biology, Novo Nordisk A/S, 2760, Maaloev, Denmark. .,Steno Diabetes Center, Niels Steensensvej 2-4, 2820, Gentofte, Denmark.
| | - Steen B Pedersen
- Department of Endocrinology MEA, Aarhus University Hospital, 8000, Aarhus, Denmark.
| | - Bjørn Richelsen
- Department of Endocrinology MEA, Aarhus University Hospital, 8000, Aarhus, Denmark.
| | | | - Kirsten Raun
- Type 2 Diabetes, Novo Nordisk A/S, 2760, Maaloev, Denmark.
| | - Kevin L Grove
- Diabetes, Obesity and Metabolism, Oregon National Primate Research Centre, Oregon Health & Science University, Portland, OR, 97006, USA. .,Obesity Research, Novo Nordisk A/S, Seattle, WA, 98109, USA.
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5
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Shukla C, Koch LG, Britton SL, Cai M, Hruby VJ, Bednarek M, Novak CM. Contribution of regional brain melanocortin receptor subtypes to elevated activity energy expenditure in lean, active rats. Neuroscience 2015; 310:252-67. [PMID: 26404873 DOI: 10.1016/j.neuroscience.2015.09.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 09/10/2015] [Accepted: 09/11/2015] [Indexed: 12/13/2022]
Abstract
Physical activity and non-exercise activity thermogenesis (NEAT) are crucial factors accounting for individual differences in body weight, interacting with genetic predisposition. In the brain, a number of neuroendocrine intermediates regulate food intake and energy expenditure (EE); this includes the brain melanocortin (MC) system, consisting of MC peptides as well as their receptors (MCR). MC3R and MC4R have emerged as critical modulators of EE and food intake. To determine how variance in MC signaling may underlie individual differences in physical activity levels, we examined behavioral response to MC receptor agonists and antagonists in rats that show high and low levels of physical activity and NEAT, that is, high- and low-capacity runners (HCR, LCR), developed by artificial selection for differential intrinsic aerobic running capacity. Focusing on the hypothalamus, we identified brain region-specific elevations in expression of MCR 3, 4, and also MC5R, in the highly active, lean HCR relative to the less active and obesity-prone LCR. Further, the differences in activity and associated EE as a result of MCR activation or suppression using specific agonists and antagonists were similarly region-specific and directly corresponded to the differential MCR expression patterns. The agonists and antagonists investigated here did not significantly impact food intake at the doses used, suggesting that the differential pattern of receptor expression may by more meaningful to physical activity than to other aspects of energy balance regulation. Thus, MCR-mediated physical activity may be a key neural mechanism in distinguishing the lean phenotype and a target for enhancing physical activity and NEAT.
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Affiliation(s)
- C Shukla
- Department of Biological Sciences, Kent State University, Kent, OH, United States; Harvard Medical School - VA Boston Healthcare System, Boston, MA, United States.
| | - L G Koch
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - S L Britton
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI, United States; Department of Molecular & Integrative Physiology, University of Michigan, Ann Arbor, MI, United States
| | - M Cai
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, United States
| | - V J Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, AZ, United States
| | - M Bednarek
- MedImmune Limited, Cambridge, United Kingdom
| | - C M Novak
- Department of Biological Sciences, Kent State University, Kent, OH, United States
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Martin ME, O'Dorisio MS, Leverich WM, Kloepping KC, Schultz MK, Schultz MK. "Click"-cyclized (68)Ga-labeled peptides for molecular imaging and therapy: synthesis and preliminary in vitro and in vivo evaluation in a melanoma model system. Recent Results Cancer Res 2013; 194:149-75. [PMID: 22918759 PMCID: PMC3799893 DOI: 10.1007/978-3-642-27994-2_9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cyclization techniques are used often to impart higher in vivo stability and binding affinity to peptide targeting vectors for molecular imaging and therapy. The two most often used techniques to impart these qualities are lactam bridge construction and disulfide bond formation. While these techniques have been demonstrated to be effective, orthogonal protection/deprotection steps can limit achievable product yields. In the work described in this chapter, new α-melanocyte stimulating hormone (α-MSH) peptide analogs were synthesized and cyclized by copper-catalyzed terminal azide-alkyne cycloaddition "click" chemistry techniques. The α-MSH peptide and its cognate receptor (melanocortin receptor subtype 1, MC1R) represent a well-characterized model system to examine the effect of the triazole linkage for peptide cyclization on receptor binding in vitro and in vivo. Four new DOTA-conjugated α-MSH analogs were cyclized and evaluated by in vitro competitive binding assays, serum stability testing, and in vivo imaging by positron emission tomography (PET) of tumor-bearing mice. These new DOTA-conjugated click-cyclized analogs exhibited selective high binding affinity (<2 nM) for MC1R on melanoma cells in vitro, high stability in human serum, and produced high-contrast PET/CT images of tumor xenografts. (68)Ga-labeled DOTA bioconjugates displayed rapid pharmacokinetics with receptor-mediated tumor accumulation of up to 16 ± 5% ID/g. The results indicate that the triazole ring is an effective bioisosteric replacement for the standard lactam bridge assemblage for peptide cyclization. Radiolabeling results confirm that Cu catalyst is sufficiently removed prior to DOTA chelator addition to enable insertion of radio metals or stable metals for molecular imaging and therapy. Thus, these click-chemistry-cyclized variants show promise as agents for melanocortin receptor-targeted imaging and radionuclide therapy.
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Affiliation(s)
- Molly E. Martin
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa
| | - M. Sue O'Dorisio
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa,Corresponding Author: Michael K. Schultz PhD, Departments of Radiology and Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa, ML B180, 500 Newton Road, Iowa City, IA 52242. Tel: +1 (319) 356-3380; Fax: +1 (319) 335-8668;
| | - Whitney M. Leverich
- Department of Pediatric Hematology/Oncology, Carver College of Medicine, The University of Iowa
| | - Kyle C. Kloepping
- Department of Radiology, Carver College of Medicine, The University of Iowa,Department of Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa
| | - Michael K. Schultz
- Department of Radiology, Carver College of Medicine, The University of Iowa,Department of Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa,Corresponding Author: Michael K. Schultz PhD, Departments of Radiology and Radiation Oncology (Free Radical Radiation Biology Program), Carver College of Medicine, The University of Iowa, ML B180, 500 Newton Road, Iowa City, IA 52242. Tel: +1 (319) 356-3380; Fax: +1 (319) 335-8668;
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7
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Møller CL, Raun K, Jacobsen ML, Pedersen TÅ, Holst B, Conde-Frieboes KW, Wulff BS. Characterization of murine melanocortin receptors mediating adipocyte lipolysis and examination of signalling pathways involved. Mol Cell Endocrinol 2011; 341:9-17. [PMID: 21616121 DOI: 10.1016/j.mce.2011.03.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 02/21/2011] [Accepted: 03/15/2011] [Indexed: 11/15/2022]
Abstract
The melanocortin receptors (MCRs) belong to the G-protein coupled receptors (family A). So far, 5 different subtypes have been described (MC1R-MC5R) and of these MC2R and MC5R have been proposed to act directly in adipocytes and regulate lipolysis in rodents. Using ACTH and α-melanocyte stimulating hormone (α-MSH) generated from proopiomelanocortin (POMC), as well as synthetic MSH analogues to stimulate lipolysis in murine 3T3-L1 adipocytes it is shown that MC2R and MC5R are lipolytic mediators in differentiated 3T3-L1 adipocytes. Involvement of cAMP, phosphorylated extracellular signal-regulated kinase (ERK) 1/2, protein kinase B (PKB), adenosine 5' monophosphate activated protein kinase (AMPK) and Jun-amino-terminal kinase (JNK) in MCR mediated lipolysis were studied. Interestingly, results obtained in 3T3-L1 cells suggest that lipolysis stimulated by α-MSH, NDP-α-MSH, MT-II, SHU9119 and PG-901 is mediated through MC5R in a cAMP independent manner. Finally, we identify essential differences in MCR mediated lipolysis when using 3T3-L1 cells compared to primary adipocytes.
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MESH Headings
- 3T3-L1 Cells
- Adipocytes/drug effects
- Adipocytes/metabolism
- Adipogenesis
- Adrenocorticotropic Hormone/pharmacology
- Adrenocorticotropic Hormone/physiology
- Animals
- Binding, Competitive
- Cyclic AMP/metabolism
- Epididymis/cytology
- Epididymis/metabolism
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Fatty Acids, Nonesterified/metabolism
- Gene Expression
- Hormones/pharmacology
- Hormones/physiology
- Lipolysis
- MAP Kinase Signaling System
- Male
- Melanocortins/pharmacology
- Melanocortins/physiology
- Mice
- Mice, Inbred C57BL
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- Receptor, Melanocortin, Type 2/agonists
- Receptor, Melanocortin, Type 2/genetics
- Receptor, Melanocortin, Type 2/metabolism
- Receptors, Melanocortin/genetics
- Receptors, Melanocortin/metabolism
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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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Bednarek MA, MacNeil T, Tang R, Fong TM, Cabello MA, Maroto M, Teran A. Cyclic analogs of alpha-melanocyte-stimulating hormone (alphaMSH) with high agonist potency and selectivity at human melanocortin receptor 1b. Peptides 2008; 29:1010-7. [PMID: 18378043 DOI: 10.1016/j.peptides.2008.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2007] [Revised: 02/05/2008] [Accepted: 02/13/2008] [Indexed: 10/22/2022]
Abstract
Alpha-melanotropin (alphaMSH), Ac-Ser1-Tyr2-Ser3-Met4-Glu5-His6-Phe7-Arg8-Trp9-Gly10-Lys11-Pro12-Val13-NH2,(1) has been long recognized as an important physiological regulator of skin and hair pigmentation in mammals. Binding of this peptide to the melanocortin receptor 1 (MC1R) leads to activation of tyrosinase, the key enzyme of the melanin biosynthesis pathway. In this study, interactions of the human MC1bR (an isoform of the receptor 1a) with the synthetic cyclic analogs of alphaMSH were studied. These ligands were analogs of MTII, Ac-Nle4-cyclo-(Asp5-His6-D-Phe7-Arg8-Trp9-Lys10)-NH2, a potent pan-agonist at the human melanocortin receptors (hMC1,3-5R). In the structure of MTII, the His6-D-Phe7-Arg8-Trp9 segment has been recognized as "essential" for molecular recognition at the human melanocortin receptors (hMC1,3-5R). Herein, the role of the Trp9 in the ligand interactions with the hMC1b,3-5R has been reevaluated. Analogs with various amino acids in place of Trp9 were synthesized and tested in vitro in receptor affinity binding and cAMP functional assays at human melanocortin receptors 1b, 3, 4 and 5 (hMC1b,3-5R). Several of the new peptides were high potency agonists (partial) at hMC1bR (EC50 from 0.5 to 20 nM) and largely inactive at hMC3-5R. The bulky aromatic side chain in position 9, such as that in Trp, was found not to be essential to agonism (partial) of the studied peptides at hMC1bR.
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MESH Headings
- Binding, Competitive
- Cyclic AMP/analysis
- Cyclic AMP/biosynthesis
- Humans
- Inhibitory Concentration 50
- Molecular Structure
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/isolation & purification
- Peptides, Cyclic/metabolism
- Peptides, Cyclic/pharmacology
- Receptor, Melanocortin, Type 1/agonists
- Receptor, Melanocortin, Type 1/chemistry
- Receptor, Melanocortin, Type 1/classification
- Sensitivity and Specificity
- Structure-Activity Relationship
- alpha-MSH/analogs & derivatives
- alpha-MSH/chemical synthesis
- alpha-MSH/chemistry
- alpha-MSH/isolation & purification
- alpha-MSH/metabolism
- alpha-MSH/pharmacology
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Affiliation(s)
- Maria A Bednarek
- Department of Medicinal Chemistry, Merck Research Laboratories, R50G-140, P.O. Box 2000, Rahway, NJ, USA.
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10
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Mayorov AV, Cai M, Palmer ES, Dedek MM, Cain JP, Van Scoy AR, Tan B, Vagner J, Trivedi D, Hruby VJ. Structure-activity relationships of cyclic lactam analogues of alpha-melanocyte-stimulating hormone (alpha-MSH) targeting the human melanocortin-3 receptor. J Med Chem 2008; 51:187-95. [PMID: 18088090 PMCID: PMC2587288 DOI: 10.1021/jm070461w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A variety of dicarboxylic acid linkers introduced between the alpha-amino group of Pro(6) and the -amino group of Lys(10) of the cyclic lactam alpha-melanocyte-stimulating hormone (alpha-MSH)-derived Pro(6)-D-Phe(7)/D-Nal(2')(7)-Arg(8)-Trp(9)-Lys(10)-NH2 pentapeptide template lead to nanomolar range and selective hMC3R agonists and antagonists. Replacement of the Pro(6) residue and the dicarboxylic acid linker with 2,3-pyrazine-dicarboxylic acid furnished a highly selective nanomolar range hMC3R partial agonist (analogue 12, c[CO-2,3-pyrazine-CO-D-Phe-Arg-Trp-Lys]-NH2, EC50 = 27 nM, 70% max cAMP) and an hMC3R antagonist (analogue 13, c[CO-2,3-pyrazine-CO-D-Nal(2')-Arg-Trp-Lys]-NH2, IC50 = 23 nM). Modeling experiments suggest that 2,3-pyrazinedicarboxylic acid stabilizes a beta-turn-like structure with the D-Phe/D-Nal(2') residues, which explains the high potency of the corresponding peptides. Placement of a Nle residue in position 6 produced a hMC3R/hMC5R antagonist (analogue 15, c[CO-(CH 2)2-CO-Nle-D-Nal(2')-Arg-Trp-Lys]-NH2, IC50 = 12 and 17 nM, respectively), similarly to the previously described cyclic gamma-melanocyte-stimulating hormone (gamma-MSH)-derived hMC3R/hMC5R antagonists. These newly developed melanotropins will serve as critical biochemical tools for elucidating the full spectrum of functions performed by the physiologically important melanocortin-3 receptor.
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MESH Headings
- Binding, Competitive
- Cell Line
- Cyclic AMP/biosynthesis
- Humans
- Lactams/chemical synthesis
- Lactams/pharmacology
- Models, Molecular
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/pharmacology
- Radioligand Assay
- Receptor, Melanocortin, Type 3/agonists
- Receptor, Melanocortin, Type 3/antagonists & inhibitors
- Receptor, Melanocortin, Type 3/chemistry
- Structure-Activity Relationship
- alpha-MSH/analogs & derivatives
- alpha-MSH/chemical synthesis
- alpha-MSH/pharmacology
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Affiliation(s)
| | - Minying Cai
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Erin S. Palmer
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Matthew M. Dedek
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - James P. Cain
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - April R. Van Scoy
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Bahar Tan
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Josef Vagner
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Dev Trivedi
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
| | - Victor J. Hruby
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721
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