1
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Klein VG, Bray WM, Wang HY, Edmondson Q, Schwochert J, Ono S, Naylor MR, Turmon AC, Faris JH, Okada O, Taunton J, Lokey RS. Identifying the Cellular Target of Cordyheptapeptide A and Synthetic Derivatives. ACS Chem Biol 2021; 16:1354-1364. [PMID: 34251165 DOI: 10.1021/acschembio.1c00094] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cordyheptapeptide A is a lipophilic cyclic peptide from the prized Cordyceps fungal genus that shows potent cytotoxicity in multiple cancer cell lines. To better understand the bioactivity and physicochemical properties of cordyheptapeptide A with the ultimate goal of identifying its cellular target, we developed a solid-phase synthesis of this multiply N-methylated cyclic heptapeptide which enabled rapid access to both side chain- and backbone-modified derivatives. Removal of one of the backbone amide N-methyl (N-Me) groups maintained bioactivity, while membrane permeability was also preserved due to the formation of a new intramolecular hydrogen bond in a low dielectric solvent. Based on its cytotoxicity profile in the NCI-60 cell line panel, as well as its phenotype in a microscopy-based cytological assay, we hypothesized that cordyheptapeptide was acting on cells as a protein synthesis inhibitor. Further studies revealed the molecular target of cordyheptapeptide A to be the eukaryotic translation elongation factor 1A (eEF1A), a target shared by other lipophilic cyclic peptide natural products. This work offers a strategy to study and improve cyclic peptide natural products while highlighting the ability of these lipophilic compounds to effectively inhibit intracellular disease targets.
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Affiliation(s)
- Victoria G. Klein
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Walter M. Bray
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Hao-Yuan Wang
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, 94158, United States
| | - Quinn Edmondson
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Joshua Schwochert
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Satoshi Ono
- Innovative Research Division, Mitsubishi Tanabe Pharma Corporation, Kanagawa 227-0033, Japan
| | - Matthew R. Naylor
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Alexandra C. Turmon
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Justin H. Faris
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
| | - Okimasa Okada
- Innovative Research Division, Mitsubishi Tanabe Pharma Corporation, Kanagawa 227-0033, Japan
| | - Jack Taunton
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, 94158, United States
| | - R. Scott Lokey
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, California 95064, United States
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2
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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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3
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Khadka NK, Teng P, Cai J, Pan J. Modulation of lipid membrane structural and mechanical properties by a peptidomimetic derived from reduced amide scaffold. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:734-744. [PMID: 28132901 DOI: 10.1016/j.bbamem.2017.01.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 01/22/2017] [Accepted: 01/25/2017] [Indexed: 10/20/2022]
Abstract
Understanding how antimicrobial peptidomimetics interact with lipid membranes is important in battling multidrug resistant bacterial pathogens. We study the effects of a recently reported peptidomimetic on lipid bilayer structural and mechanical properties. The compound referred to as E107-3 is synthesized based on the acylated reduced amide scaffold and has been shown to exhibit good antimicrobial potency. Our vesicle leakage assay indicates that the compound increases lipid bilayer permeability. We use micropipette aspiration to explore the kinetic response of giant unilamellar vesicles (GUVs). Exposure to the compound causes the GUV protrusion length LP to spontaneously increase and then decrease, followed by GUV rupture. Solution atomic force microscopy (AFM) is used to visualize lipid bilayer structural modulation within a nanoscopic regime. Unlike melittin, which produces pore-like structures, the peptidomimetic compound is found to induce nanoscopic heterogeneous structures. Finally, we use AFM-based force spectroscopy to study the impact of the compound on lipid bilayer mechanical properties. We find that incremental addition of the compound to planar lipid bilayers results in a moderate decrease of the bilayer puncture force FP and a 39% decrease of the bilayer area compressibility modulus KA. To explain our experimental data, we propose a membrane interaction model encompassing disruption of lipid chain packing and extraction of lipid molecules. The later action mode is supported by our observation of a double-bilayer structure in the presence of fusogenic calcium ions.
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Affiliation(s)
- Nawal K Khadka
- Department of Physics, University of South Florida, Tampa, FL 33620, United States
| | - Peng Teng
- Department of Chemistry, University of South Florida, Tampa, FL 33620, United States
| | - Jianfeng Cai
- Department of Chemistry, University of South Florida, Tampa, FL 33620, United States
| | - Jianjun Pan
- Department of Physics, University of South Florida, Tampa, FL 33620, United States.
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4
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Teng P, Huo D, Nimmagadda A, Wu J, She F, Su M, Lin X, Yan J, Cao A, Xi C, Hu Y, Cai J. Small Antimicrobial Agents Based on Acylated Reduced Amide Scaffold. J Med Chem 2016; 59:7877-87. [PMID: 27526720 DOI: 10.1021/acs.jmedchem.6b00640] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Prevalence of drug-resistant bacteria has emerged to be one of the greatest threats in the 21st century. Herein, we report the development of a series of small molecular antibacterial agents that are based on the acylated reduced amide scaffold. These molecules display good potency against a panel of multidrug-resistant Gram-positive and Gram-negative bacterial strains. Meanwhile, they also effectively inhibit the biofilm formation. Mechanistic studies suggest that these compounds kill bacteria by compromising bacterial membranes, a mechanism analogous to that of host-defense peptides (HDPs). The mechanism is further supported by the fact that the lead compounds do not induce resistance in MRSA bacteria even after 14 passages. Lastly, we also demonstrate that these molecules have therapeutic potential by preventing inflammation caused by MRSA induced pneumonia in a rat model. This class of compounds could lead to an appealing class of antibiotic agents combating drug-resistant bacterial strains.
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Affiliation(s)
- Peng Teng
- Department of Chemistry, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Da Huo
- Department of Biomedical Engineering, College of Engineering and Applied Science, Nanjing University , 22 Hankou Road, Nanjing, Jiangsu 210093, P. R. China
| | - Alekhya Nimmagadda
- Department of Chemistry, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Jianfeng Wu
- Department of Environmental Health Sciences, University of Michigan School of Public Health , 1415 Washington Heights, Ann Arbor, Michigan 48109, United States
| | - Fengyu She
- Department of Chemistry, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Ma Su
- Department of Chemistry, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Xiaoyang Lin
- College of Pharmacy, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Jiyu Yan
- College of Pharmacy, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Annie Cao
- Department of Chemistry, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Chuanwu Xi
- Department of Environmental Health Sciences, University of Michigan School of Public Health , 1415 Washington Heights, Ann Arbor, Michigan 48109, United States
| | - Yong Hu
- Department of Biomedical Engineering, College of Engineering and Applied Science, Nanjing University , 22 Hankou Road, Nanjing, Jiangsu 210093, P. R. China
| | - Jianfeng Cai
- Department of Chemistry, University of South Florida , 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
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5
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Doering SR, Todorovic A, Haskell-Luevano C. Melanocortin antagonist tetrapeptides with minimal agonist activity at the mouse melanocortin-3 receptor. ACS Med Chem Lett 2015; 6:123-7. [PMID: 25699138 PMCID: PMC4329596 DOI: 10.1021/ml500340z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 12/28/2014] [Indexed: 11/28/2022] Open
Abstract
The melanocortin system regulates many important functions in the body. There are five melanocortin G protein-coupled receptor subtypes known to date. Herein, we report a structure-activity relationship (SAR) study of a tetrapeptide lead discovered through a double substitution strategy at the melanocortin core His-Phe-Arg-Trp sequence. Several compounds were identified with micromolar agonist activity at the mouse melanocortin-1 (mMC1R) and mouse melanocortin-5 receptor (mMC5R) subtypes, weak antagonist activity at the mouse melanocortin-3 receptor (mMC3R), and potent antagonist activity at the mouse melanocortin-4 receptor (mMC4R). Two compounds (2 and 3) were nanomolar mMC4R antagonists with no mMC3R antagonist activity observed. Additionally, we identified three tetrapeptide MC3R antagonists (1, 6, and 7) that possess minimal mMC3R agonist activity only at 100 μM, not commonly observed for mMC3R/mMC4R antagonists. These novel molecular templates have the potential as molecular probes to better differentiate the roles of the centrally expressed MC3 and MC4 receptors.
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Affiliation(s)
- Skye R. Doering
- Department
of Medicinal Chemistry, University of Minnesota, Twin Cities, Minnesota 55455, United States
| | - Aleksandar Todorovic
- Department
of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
| | - Carrie Haskell-Luevano
- Department
of Medicinal Chemistry, University of Florida, Gainesville, Florida 32610, United States
- Department
of Medicinal Chemistry, University of Minnesota, Twin Cities, Minnesota 55455, United States
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6
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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: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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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7
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Baber JC, Lowe R, Saunders J, Feher M. Automated generation of turn mimetics: Proof of concept study for the MC4 receptor. Bioorg Med Chem 2012; 20:3565-74. [DOI: 10.1016/j.bmc.2012.04.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/29/2012] [Accepted: 04/03/2012] [Indexed: 12/21/2022]
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8
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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: 14] [Impact Index Per Article: 1.1] [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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9
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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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10
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Katritzky AR, Khashab NM, Yoshioka M, Haase DN, Wilson KR, Johnson JV, Chung A, Haskell-Luevano C. Microwave-Assisted Solid-Phase Peptide Synthesis Utilizing N-Fmoc-Protected (α-aminoacyl)benzotriazoles. Chem Biol Drug Des 2007; 70:465-8. [DOI: 10.1111/j.1747-0285.2007.00584.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Todorovic A, Joseph CG, Sorensen NB, Wood MS, Haskell-Luevano C. Structure-activity relationships of melanocortin agonists containing the benzimidazole scaffold. Chem Biol Drug Des 2007; 69:338-49. [PMID: 17539826 DOI: 10.1111/j.1747-0285.2007.00511.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The melanocortin system has been implicated in regulating various physiological processes including pigmentation, energy homeostasis, obesity, steroidogenesis cardiovascular, and exocrine gland function. The five melanocortin receptors that belong to the super family of G protein-coupled receptors are stimulated by naturally occurring agonists. The aim of this research was focused on the design, synthesis, and pharmacological characterization of melanocortin ligands that contain the 1,2,5-trisubstituted benzimidazole scaffold. A series of benzimidazole analogues, with three points of diversity at positions 1, 2, and 5, were designed, synthesized, pharmacologically assayed at the mouse melanocortin receptors MC1R, MC3R, MC4R, and MC5R and resulted in ligands possessing a range of agonist activity from nm to no stimulation at up to 100 microM concentrations. This study demonstrates that the benzimidazole structure template can be appended with key melanocortin agonist amino acids for the design melanocortin receptor agonist ligands.
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Affiliation(s)
- Aleksandar Todorovic
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, FL 32610, USA
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12
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Boeglin D, Xiang Z, Sorenson NB, Wood MS, Haskell-Luevano C, Lubell WD. Aza-scanning of the Potent Melanocortin Receptor Agonist Ac-His-d-Phe-Arg-Trp-NH2. Chem Biol Drug Des 2006; 67:275-83. [PMID: 16629825 DOI: 10.1111/j.1747-0285.2006.00378.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The melanocortin pathway is an important participant in the regulation of skin pigmentation, steroidogenesis, obesity, energy homeostasis, and exocrine gland function. Melanocortin agonists contain the putative sequence 'His-Phe-Arg-Trp', which has been designated as the 'message' sequence for melanocortin peptides, and this sequence has been hypothesized to adopt a bioactive reverse turn conformation. Exploring the relationship between its structure and biological activity, we report the synthesis and evaluation of seven aza-analogs of the potent melanocortin receptor agonist Ac-His-D-Phe-Arg-Trp-NH2. Aza-amino acids, in which the alpha-carbon was replaced by nitrogen, were inserted along the peptide sequence to probe the importance of local configuration and turn conformation on the biology of this tetrapeptide. Although systematic substitution of aza-amino acids for the D-Phe and Arg residues led to a significant loss of activity relative to the parent peptide for all melanocortin receptor subtypes examined, substitution of aza-amino acids at the C-terminal Trp residue gave analogs equipotent to the parent peptide. In summary, the aza-scan has demonstrated that recognition of this tetrapeptide by the melanocortin receptors is particularly sensitive to modifications of configuration and conformation at the D-Phe and Arg residues versus the Trp amino acid. In light of aza-residues imparting resistance from enzymatic degradation, C-terminal aza-amino acid analogs may be used to design new peptide mimics with enhanced metabolic stability.
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MESH Headings
- Animals
- Aza Compounds/chemistry
- Aza Compounds/metabolism
- Aza Compounds/pharmacology
- Cells, Cultured
- Mice
- Oligopeptides/chemistry
- Oligopeptides/metabolism
- Oligopeptides/pharmacology
- Peptides, Cyclic/chemical synthesis
- Peptides, Cyclic/chemistry
- Peptides, Cyclic/metabolism
- Protein Structure, Secondary
- Receptor, Melanocortin, Type 1/genetics
- Receptor, Melanocortin, Type 1/metabolism
- Receptor, Melanocortin, Type 3/genetics
- Receptor, Melanocortin, Type 3/metabolism
- Receptor, Melanocortin, Type 4/genetics
- Receptor, Melanocortin, Type 4/metabolism
- Receptors, Corticotropin/genetics
- Receptors, Corticotropin/metabolism
- Receptors, Melanocortin/agonists
- Receptors, Melanocortin/metabolism
- Structure-Activity Relationship
- Transfection
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Affiliation(s)
- D Boeglin
- Département de Chimie, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada
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13
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Tian X, Chen X, Gan L, Hayes JC, Switzer AG, Solinsky MG, Ebetino FH, Wos JA, Pinney BB, Farmer JA, Crossdoersen D, Sheldon RJ. Synthesis of Tic-D-Phe Psi[CH2-CH2] isostere and its use in the development of melanocortin receptor agonists. Bioorg Med Chem Lett 2005; 16:1721-5. [PMID: 16376076 DOI: 10.1016/j.bmcl.2005.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Revised: 11/30/2005] [Accepted: 12/01/2005] [Indexed: 11/15/2022]
Abstract
The first synthesis of Tic-D-Phe Psi[CH(2)-CH(2)] isostere is described, which features diastereoselective alkylation of the tricyclic lactam 14. The use of this novel dipeptide isostere in the development of melanocortin agonists has been demonstrated by the synthesis of peptidomimetic 7 and non-peptidic ligand 27. Both compounds displayed significant binding and agonist potency at the MC4R.
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Affiliation(s)
- Xinrong Tian
- Health Care Research Center, Procter & Gamble Pharmaceuticals, 8700 Mason Montgomery Road, Mason, OH 45040, USA.
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14
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Todorovic A, Haskell-Luevano C. A review of melanocortin receptor small molecule ligands. Peptides 2005; 26:2026-36. [PMID: 16051395 DOI: 10.1016/j.peptides.2004.11.024] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2004] [Accepted: 11/18/2004] [Indexed: 11/22/2022]
Abstract
The melanocortin system (MC) is implicated in the regulation of a variety of physiological pathways including pigmentation, steroid function, energy homeostasis, food intake, obesity, cardiovascular, sexual function, and normal gland regulation. The melanocortin system consists of five receptors identified to date (MC1-5R), melanocortin agonists derived from the pro-opiomelanocortin prohormone (POMC) and two naturally existing antagonists. Melanocortin receptor ligand structure-activity studies have been performed since the 1960s, primarily focused on the pigmentation aspect of physiology. During the 1990s, the melanocortin-4 receptor was identified to play a significant physiological role in the regulation of both food intake and obesity. Subsequently, a concerted drug design effort has focused on the design and discovery of melanocortin receptor small molecules. Herein, we present an overview of melanocortin receptor heterocyclic small molecules.
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Affiliation(s)
- Aleksandar Todorovic
- Department of Medicinal Chemistry, University of Florida, P.O. Box 100485, Gainesville, FL 32610, USA
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