1
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Gimenez LE, Martin C, Yu J, Hollanders C, Hernandez CC, Wu Y, Yao D, Han GW, Dahir NS, Wu L, Van der Poorten O, Lamouroux A, Mannes M, Zhao S, Tourwé D, Stevens RC, Cone RD, Ballet S. Novel Cocrystal Structures of Peptide Antagonists Bound to the Human Melanocortin Receptor 4 Unveil Unexplored Grounds for Structure-Based Drug Design. J Med Chem 2024; 67:2690-2711. [PMID: 38345933 DOI: 10.1021/acs.jmedchem.3c01822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Melanocortin 4 receptor (MC4-R) antagonists are actively sought for treating cancer cachexia. We determined the structures of complexes with PG-934 and SBL-MC-31. These peptides differ from SHU9119 by substituting His6 with Pro6 and inserting Gly10 or Arg10. The structures revealed two subpockets at the TM7-TM1-TM2 domains, separated by N2857.36. Two peptide series based on the complexed peptides led to an antagonist activity and selectivity SAR study. Most ligands retained the SHU9119 potency, but several SBL-MC-31-derived peptides significantly enhanced MC4-R selectivity over MC1-R by 60- to 132-fold. We also investigated MC4-R coupling to the K+ channel, Kir7.1. Some peptides activated the channel, whereas others induced channel closure independently of G protein coupling. In cell culture studies, channel activation correlated with increased feeding, while a peptide with Kir7.1 inhibitory activity reduced eating. These results highlight the potential for targeting the MC4-R:Kir7.1 complex for treating positive and restrictive eating disorders.
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Affiliation(s)
- Luis E Gimenez
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Charlotte Martin
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
| | - Jing Yu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Charlie Hollanders
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
| | - Ciria C Hernandez
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Yiran Wu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Deqiang Yao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Gye Won Han
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, California 90089, United States
| | - Naima S Dahir
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Lijie Wu
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Olivier Van der Poorten
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
| | - Arthur Lamouroux
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
| | - Morgane Mannes
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
| | - Suwen Zhao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Dirk Tourwé
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
| | - Raymond C Stevens
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Roger D Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Molecular, Cellular, and Developmental Biology, College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Steven Ballet
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, Brussels B-1050, Belgium
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2
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Ericson MD, Freeman KT, LaVoi TM, Donow HM, Santos RG, Giulianotti MA, Pinilla C, Houghten RA, Haskell-Luevano C. The Parallel Structure-Activity Relationship Screening of Three Compounds Identifies the Common Agonist Pharmacophore of Pyrrolidine Bis-Cyclic Guanidine Melanocortin-3 Receptor (MC3R) Small-Molecule Ligands. Int J Mol Sci 2023; 24:10145. [PMID: 37373293 DOI: 10.3390/ijms241210145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 05/07/2023] [Accepted: 05/10/2023] [Indexed: 06/29/2023] Open
Abstract
The melanocortin receptors are involved in numerous physiological pathways, including appetite, skin and hair pigmentation, and steroidogenesis. In particular, the melanocortin-3 receptor (MC3R) is involved in fat storage, food intake, and energy homeostasis. Small-molecule ligands developed for the MC3R may serve as therapeutic lead compounds for treating disease states of energy disequilibrium. Herein, three previously reported pyrrolidine bis-cyclic guanidine compounds with five sites for molecular diversity (R1-R5) were subjected to parallel structure-activity relationship studies to identify the common pharmacophore of this scaffold series required for full agonism at the MC3R. The R2, R3, and R5 positions were required for full MC3R efficacy, while truncation of either the R1 or R4 positions in all three compounds resulted in full MC3R agonists. Two additional fragments, featuring molecular weights below 300 Da, were also identified that possessed full agonist efficacy and micromolar potencies at the mMC5R. These SAR experiments may be useful in generating new small-molecule ligands and chemical probes for the melanocortin receptors to help elucidate their roles in vivo and as therapeutic lead compounds.
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Affiliation(s)
- Mark D Ericson
- Department of Medicinal Chemistry & Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Katie T Freeman
- Department of Medicinal Chemistry & Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
| | - Travis M LaVoi
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA
| | - Haley M Donow
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA
| | - Radleigh G Santos
- Department of Mathematics, Nova Southeastern University, Fort Lauderdale, FL 33314, USA
| | - Marc A Giulianotti
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA
| | - Clemencia Pinilla
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA
| | - Richard A Houghten
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry & Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55455, USA
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3
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Tao YX. Mutations in melanocortin-4 receptor: From fish to men. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2022; 189:215-257. [PMID: 35595350 DOI: 10.1016/bs.pmbts.2022.03.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Melanocortin-4 receptor (MC4R), expressed abundantly in the hypothalamus, is a critical regulator of energy homeostasis, including both food intake and energy expenditure. Shortly after the publication in 1997 of the Mc4r knockout phenotypes in mice, including increased food intake and severe obesity, the first mutations in MC4R were reported in humans in 1998. Studies in the subsequent two decades have established MC4R mutation as the most common monogenic form of obesity, especially in early-onset severe obesity. Studies in animals, from fish to mammals, have established the conserved physiological roles of MC4R in all vertebrates in regulating energy balance. Drug targeting MC4R has been recently approved for treating morbid genetic obesity. How the MC4R can be exploited for animal production is highly worthy of active investigation.
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Affiliation(s)
- Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.
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4
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Fatima MT, Ahmed I, Fakhro KA, Akil ASA. Melanocortin-4 receptor complexity in energy homeostasis,obesity and drug development strategies. Diabetes Obes Metab 2022; 24:583-598. [PMID: 34882941 PMCID: PMC9302617 DOI: 10.1111/dom.14618] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/05/2021] [Accepted: 12/06/2021] [Indexed: 12/19/2022]
Abstract
The melanocortin-4 receptor (MC4R) has been critically investigated for the past two decades, and novel findings regarding MC4R signalling and its potential exploitation in weight loss therapy have lately been emphasized. An association between MC4R and obesity is well established, with disease-causing mutations affecting 1% to 6% of obese patients. More than 200 MC4R variants have been reported, although conflicting results as to their effects have been found in different cohorts. Most notably, some MC4R gain-of-function variants seem to rescue obesity and related complications via specific pathways such as beta-arrestin (ß-arrestin) recruitment. Broadly speaking, however, dysfunctional MC4R dysregulates satiety and induces hyperphagia. The picture at the mechanistic level is complicated as, in addition to the canonical G stimulatory pathway, the ß-arrestin signalling pathway and ions (particularly calcium) seem to interact with MC4R signalling to contribute to or alleviate obesity pathogenesis. Thus, the overall complexity of the MC4R signalling spectra has broadened considerably, indicating there is great potential for the development of new drugs to manage obesity and its related complications. Alpha-melanocyte-stimulating hormone is the major endogenous MC4R agonist, but structure-based ligand discovery studies have identified possible superior and selective agonists that can improve MC4R function. However, some of these agonists characterized in vitro and in vivo confer adverse effects in patients, as demonstrated in clinical trials. In this review, we provide a comprehensive insight into the genetics, function and regulation of MC4R and its contribution to obesity. We also outline new approaches in drug development and emerging drug candidates to treat obesity.
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Affiliation(s)
- Munazza Tamkeen Fatima
- Department of Human Genetics, Translational Medicine DivisionResearch Branch, Sidra MedicineDohaQatar
| | - Ikhlak Ahmed
- Department of Human Genetics, Translational Medicine DivisionResearch Branch, Sidra MedicineDohaQatar
| | - Khalid Adnan Fakhro
- Department of Human Genetics, Translational Medicine DivisionResearch Branch, Sidra MedicineDohaQatar
- Department of Genetic MedicineWeill Cornell MedicineDohaQatar
- College of Health and Life SciencesHamad Bin Khalifa UniversityDohaQatar
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5
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Ericson MD, Doering SR, Larson CM, Freeman KT, LaVoi TM, Donow HM, Santos RG, Cho RH, Koerperich ZM, Giulianotti MA, Pinilla C, Houghten RA, Haskell-Luevano C. Functional Mixture-Based Positional Scan Identifies a Library of Antagonist Tetrapeptide Sequences (LAtTeS) with Nanomolar Potency for the Melanocortin-4 Receptor and Equipotent with the Endogenous AGRP(86-132) Antagonist. J Med Chem 2021; 64:14860-14875. [PMID: 34592820 DOI: 10.1021/acs.jmedchem.1c01417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The melanocortin-4 receptor (MC4R) plays an important role in appetite. Agonist ligands that stimulate the MC4R decrease appetite, while antagonist compounds increase food consumption. Herein, a functional mixture-based positional scan identified novel MC4R antagonist sequences. Mixtures comprising a library of 12,960,000 tetrapeptides were screened in the presence and absence of the NDP-MSH agonist. These results led to the synthesis of 48 individual tetrapeptides, of which 40 were screened for functional activity at the melanocortin receptors. Thirteen compounds were found to possess nanomolar antagonist potency at the MC4R, with the general tetrapeptide sequence Ac-Aromatic-Basic-Aromatic-Basic-NH2. The most notable results include the identification of tetrapeptide 48 [COR1-25, Ac-DPhe(pI)-Arg-Nal(2')-Arg-NH2], an equipotent MC4R antagonist to agouti-related protein [AGRP(86-132)], more potent than miniAGRP(87-120), and possessing 15-fold selectivity for the MC4R versus the MC3R. These tetrapeptides may serve as leads for novel appetite-inducing therapies to treat states of negative energy balance, such as cachexia and anorexia.
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Affiliation(s)
- Mark D Ericson
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Skye R Doering
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Courtney M Larson
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katie T Freeman
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Travis M LaVoi
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Haley M Donow
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Radleigh G Santos
- Nova Southeastern University, 3301 College Avenue, Fort Lauderdale, Florida 33314, United States
| | - Rachel H Cho
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Zoe M Koerperich
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Marc A Giulianotti
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Clemencia Pinilla
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Richard A Houghten
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translation Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
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6
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Doering SR, Freeman K, Debevec G, Geer P, Santos RG, Lavoi TM, Giulianotti MA, Pinilla C, Appel JR, Houghten RA, Ericson MD, Haskell-Luevano C. Discovery of Nanomolar Melanocortin-3 Receptor (MC3R)-Selective Small Molecule Pyrrolidine Bis-Cyclic Guanidine Agonist Compounds Via a High-Throughput "Unbiased" Screening Campaign. J Med Chem 2021; 64:5577-5592. [PMID: 33886285 PMCID: PMC8552302 DOI: 10.1021/acs.jmedchem.0c02041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The central melanocortin-3 and melanocortin-4 receptors (MC3R, MC4R) are key regulators of body weight and energy homeostasis. Herein, the discovery and characterization of first-in-class small molecule melanocortin agonists with selectivity for the melanocortin-3 receptor over the melanocortin-4 receptor are reported. Identified via "unbiased" mixture-based high-throughput screening approaches, pharmacological evaluation of these pyrrolidine bis-cyclic guanidines resulted in nanomolar agonist activity at the melanocortin-3 receptor. The pharmacological profiles at the remaining melanocortin receptor subtypes tested indicated similar agonist potencies at both the melanocortin-1 and melanocortin-5 receptors and antagonist or micromolar agonist activities at the melanocortin-4 receptor. This group of small molecules represents a new area of chemical space for the melanocortin receptors with mixed receptor pharmacology profiles that may serve as novel lead compounds to modulate states of dysregulated energy balance.
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Affiliation(s)
- Skye R Doering
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katie Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Ginamarie Debevec
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Phaedra Geer
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Radleigh G Santos
- Nova Southeastern University, 3301 College Avenue, Fort Lauderdale, Florida 33314, United States
| | - Travis M Lavoi
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Marc A Giulianotti
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Clemencia Pinilla
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Jon R Appel
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Richard A Houghten
- Florida International University, Port St. Lucie, Florida 34987, United States
| | - Mark D Ericson
- 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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7
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Fleming KA, Freeman KT, Powers MD, Santos RG, Debevec G, Giulianotti MA, Houghten RA, Doering SR, Pinilla C, Haskell-Luevano C. Discovery of Polypharmacological Melanocortin-3 and -4 Receptor Probes and Identification of a 100-Fold Selective nM MC3R Agonist versus a μM MC4R Partial Agonist. J Med Chem 2019; 62:2738-2749. [PMID: 30741545 DOI: 10.1021/acs.jmedchem.9b00053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The centrally expressed melanocortin-3 and melanocortin-4 receptors (MC3R and MC4R, respectively) are established targets to treat diseases of positive- and negative-energy homeostasis. We previously reported [ Doering , S. R. ; J. Med. Chem. 2017 , 60 , 4342 - 4357 ] mixture-based positional scanning approaches to identify dual MC3R agonist and MC4R antagonist tetrapeptides. Herein, 46 tetrapeptides were chosen for MC3R agonist screening selectivity profiles, synthesized, and pharmacologically characterized at the mouse melanocortin-1, -3, -4, and -5 receptors. Substitutions to the tetrapeptide template were selected solely based on MC3R agonist potency from the mixture-based screen. This study resulted in the discovery of compound 42 (Ac-Val-Gln-(pI)DPhe-DTic-NH2), a full MC3R agonist that is 100-fold selective for the MC3R over the μM MC4R partial agonist pharmacology. This compound represents a first-in-class MC3R selective agonist. This ligand will serve as a useful in vivo molecular probe for the investigation of the roles of the MC3R and MC4R in diseases of dysregulated energy homeostasis.
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Affiliation(s)
- Katlyn A Fleming
- 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
| | - Mike D Powers
- Department of Medicinal Chemistry , University of Minnesota , Minneapolis , Minnesota 55455 , United States
| | - Radleigh G Santos
- Torrey Pines Institute for Molecular Studies , Port St. Lucie , Florida 34987 , United States
| | - Ginamarie Debevec
- 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
| | - Richard A Houghten
- Torrey Pines Institute for Molecular Studies , Port St. Lucie , Florida 34987 , United States
| | - Skye R Doering
- 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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8
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Todorovic A, Lensing CJ, Holder JR, Scott JW, Sorensen NB, Haskell-Luevano C. Discovery of Melanocortin Ligands via a Double Simultaneous Substitution Strategy Based on the Ac-His-dPhe-Arg-Trp-NH 2 Template. ACS Chem Neurosci 2018; 9:2753-2766. [PMID: 29783840 DOI: 10.1021/acschemneuro.8b00181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The melanocortin system regulates an array of diverse physiological functions including pigmentation, feeding behavior, energy homeostasis, cardiovascular regulation, sexual function, and steroidogenesis. Endogenous melanocortin agonist ligands all possess the minimal messaging tetrapeptide sequence His-Phe-Arg-Trp. Based on this endogenous sequence, the Ac-His1-dPhe2-Arg3-Trp4-NH2 tetrapeptide has previously been shown to be a useful scaffold when utilizing traditional positional scanning approaches to modify activity at the various melanocortin receptors (MC1-5R). The study reported herein was undertaken to evaluate a double simultaneous substitution strategy as an approach to further diversify the Ac-His1-dPhe2-Arg3-Trp4-NH2 tetrapeptide with concurrent introduction of natural and unnatural amino acids at positions 1, 2, or 4, as well as an octanoyl residue at the N-terminus. The designed library includes the following combinations: (A) double simultaneous substitution at capping group position (Ac) together with position 1, 2, or 4, (B) double simultaneous substitution at positions 1 and 2, (C) double simultaneous substitution at positions 1 and 4, and (D) double simultaneous substitution at positions 2 and 4. Several lead ligands with unique pharmacologies were discovered in the current study including antagonists targeting the neuronal mMC3R with minimal agonist activity and ligands with selective profiles for the various melanocortin subtypes. The results suggest that the double simultaneous substitution strategy is a suitable approach in altering melanocortin receptor potency or selectivity or converting agonists into antagonists and vice versa.
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Affiliation(s)
- Aleksandar Todorovic
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Cody J. Lensing
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jerry Ryan Holder
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Joseph W. Scott
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Nicholas B. Sorensen
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
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9
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Abstract
During the last two decades, the pharmaceutical industry has progressed from detecting small molecules to designing biologic-based therapeutics. Amino acid-based drugs are a group of biologic-based therapeutics that can effectively combat the diseases caused by drug resistance or molecular deficiency. Computational techniques play a key role to design and develop the amino acid-based therapeutics such as proteins, peptides and peptidomimetics. In this study, it was attempted to discuss the various elements for computational design of amino acid-based therapeutics. Protein design seeks to identify the properties of amino acid sequences that fold to predetermined structures with desirable structural and functional characteristics. Peptide drugs occupy a middle space between proteins and small molecules and it is hoped that they can target "undruggable" intracellular protein-protein interactions. Peptidomimetics, the compounds that mimic the biologic characteristics of peptides, present refined pharmacokinetic properties compared to the original peptides. Here, the elaborated techniques that are developed to characterize the amino acid sequences consistent with a specific structure and allow protein design are discussed. Moreover, the key principles and recent advances in currently introduced computational techniques for rational peptide design are spotlighted. The most advanced computational techniques developed to design novel peptidomimetics are also summarized.
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Affiliation(s)
- Tayebeh Farhadi
- Chronic Respiratory Diseases Research Center (CRDRC), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Seyed MohammadReza Hashemian
- Chronic Respiratory Diseases Research Center (CRDRC), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Clinical Tuberculosis and Epidemiology Research Center, National Research Institute of Tuberculosis and Lung Disease, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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10
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Gonçalves JPL, Palmer D, Meldal M. MC4R Agonists: Structural Overview on Antiobesity Therapeutics. Trends Pharmacol Sci 2018; 39:402-423. [PMID: 29478721 DOI: 10.1016/j.tips.2018.01.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 01/28/2018] [Accepted: 01/30/2018] [Indexed: 01/08/2023]
Abstract
The melanocortin-4 receptor (MC4R) regulates adipose tissue formation and energy homeostasis, and is believed to be a monogenic target for novel antiobesity therapeutics. Several research efforts targeting this receptor have identified potent and selective agonists. While viable agonists have been characterized in vitro, undesirable side effects frequently appeared during clinical trials. The most promising candidates have diverse structures, including linear peptides, cyclic peptides, and small molecules. Herein, we present a compilation of potent MC4R agonists and discuss the pivotal structural differences within those molecules that resulted in good selectivity for MC4R over other melanocortins. We provide insight on recent progress in the field and reflect on directions for development of new agonists.
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Affiliation(s)
- Juliana Pereira Lopes Gonçalves
- Center for Evolutionary Chemical Biology, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
| | - Daniel Palmer
- Center for Evolutionary Chemical Biology, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark
| | - Morten Meldal
- Center for Evolutionary Chemical Biology, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
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11
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Tran T, Chiem K, Jani S, Arivett BA, Lin DL, Lad R, Jimenez V, Farone MB, Debevec G, Santos R, Giulianotti M, Pinilla C, Tolmasky ME. Identification of a small molecule inhibitor of the aminoglycoside 6'-N-acetyltransferase type Ib [AAC(6')-Ib] using mixture-based combinatorial libraries. Int J Antimicrob Agents 2018; 51:752-761. [PMID: 29410367 DOI: 10.1016/j.ijantimicag.2018.01.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 01/13/2018] [Accepted: 01/24/2018] [Indexed: 11/28/2022]
Abstract
The aminoglycoside, 6'-N-acetyltransferase type Ib [AAC(6')-Ib] is the most widely distributed enzyme among AAC(6')-I-producing Gram-negative pathogens and confers resistance to clinically relevant aminoglycosides, including amikacin. This enzyme is therefore an ideal target for enzymatic inhibitors that could overcome resistance to aminoglycosides. The search for inhibitors was carried out using mixture-based combinatorial libraries, the scaffold ranking approach, and the positional scanning strategy. A library with high inhibitory activity had pyrrolidine pentamine scaffold and was selected for further analysis. This library contained 738,192 compounds with functionalities derived from 26 different amino acids (R1, R2 and R3) and 42 different carboxylic acids (R4) in four R-group functionalities. The most active compounds all contained S-phenyl (R1 and R3) and S-hydromethyl (R2) functionalities at three locations and differed at the R4 position. The compound containing 3-phenylbutyl at R4 (compound 206) was a robust enzymatic inhibitor in vitro, in combination with amikacin it potentiated the inhibition of growth of three resistant bacteria in culture, and it improved survival when used as treatment of Galleria mellonella infected with aac(6')-Ib-harboring Klebsiella pneumoniae and Acinetobacter baumannii strains.
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Affiliation(s)
- Tung Tran
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA
| | - Kevin Chiem
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA
| | - Saumya Jani
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA
| | - Brock A Arivett
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN; Department of Chemistry, Middle Tennessee State University, Murfreesboro, TN
| | - David L Lin
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA
| | - Rupali Lad
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA
| | - Verónica Jimenez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA
| | - Mary B Farone
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN
| | | | - Radleigh Santos
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL
| | - Marc Giulianotti
- Torrey Pines Institute for Molecular Studies, Port St. Lucie, FL
| | | | - Marcelo E Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA.
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12
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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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13
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Van der Poorten O, Knuhtsen A, Sejer Pedersen D, Ballet S, Tourwé D. Side Chain Cyclized Aromatic Amino Acids: Great Tools as Local Constraints in Peptide and Peptidomimetic Design. J Med Chem 2016; 59:10865-10890. [PMID: 27690430 DOI: 10.1021/acs.jmedchem.6b01029] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Constraining the conformation of flexible peptides is a proven strategy to increase potency, selectivity, and metabolic stability. The focus has mostly been on constraining the backbone dihedral angles; however, the correct orientation of the amino acid side chains (χ-space) that constitute the peptide pharmacophore is equally important. Control of χ-space utilizes conformationally constrained amino acids that favor, disfavor, or exclude the gauche (-), the gauche (+), or the trans conformation. In this review we focus on cyclic aromatic amino acids in which the side chain is connected to the peptide backbone to provide control of χ1- and χ2-space. The manifold applications for cyclized analogues of the aromatic amino acids Phe, Tyr, Trp, and His within peptide medicinal chemistry are showcased herein with examples of enzyme inhibitors and ligands for G protein-coupled receptors.
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Affiliation(s)
- Olivier Van der Poorten
- Research Group of Organic Chemistry, Departments of Chemistry and Bio-Engineering Sciences, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium
| | - Astrid Knuhtsen
- Department of Drug Design and Pharmacology, University of Copenhagen , Jagtvej 162, 2100 Copenhagen, Denmark
| | - Daniel Sejer Pedersen
- Department of Drug Design and Pharmacology, University of Copenhagen , Jagtvej 162, 2100 Copenhagen, Denmark
| | - Steven Ballet
- Research Group of Organic Chemistry, Departments of Chemistry and Bio-Engineering Sciences, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium
| | - Dirk Tourwé
- Research Group of Organic Chemistry, Departments of Chemistry and Bio-Engineering Sciences, Vrije Universiteit Brussel , Pleinlaan 2, 1050 Brussels, Belgium
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14
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Lensing CJ, Freeman KT, Schnell SM, Adank DN, Speth RC, Haskell-Luevano C. An in Vitro and in Vivo Investigation of Bivalent Ligands That Display Preferential Binding and Functional Activity for Different Melanocortin Receptor Homodimers. J Med Chem 2016; 59:3112-28. [PMID: 26959173 DOI: 10.1021/acs.jmedchem.5b01894] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Pharmacological probes for the melanocortin receptors have been utilized for studying various disease states including cancer, sexual function disorders, Alzheimer's disease, social disorders, cachexia, and obesity. This study focused on the design and synthesis of bivalent ligands to target melanocortin receptor homodimers. Lead ligands increased binding affinity by 14- to 25-fold and increased cAMP signaling potency by 3- to 5-fold compared to their monovalent counterparts. Unexpectedly, different bivalent ligands showed preferences for particular melanocortin receptor subtypes depending on the linker that connected the binding scaffolds, suggesting structural differences between the various dimer subtypes. Homobivalent compound 12 possessed a functional profile that was unique from its monovalent counterpart providing evidence of the discrete effects of bivalent ligands. Lead compound 7 significantly decreased feeding in mice after intracerebroventricular administration. To the best of our knowledge, this is the first report of a melanocortin bivalent ligand's in vivo physiological effects.
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Affiliation(s)
- Cody J Lensing
- 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
| | - Danielle N Adank
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Robert C Speth
- College of Pharmacy, Nova Southeastern University , Fort Lauderdale, Florida 33328-2018, United States.,Department of Pharmacology and Physiology, Georgetown University , Washington, D.C. 20057, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry, University of Minnesota , Minneapolis, Minnesota 55455, United States
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15
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Singh A, Kast J, Dirain MLS, Huang H, Haskell-Luevano C. Synthesis and Structure-Activity Relationships of Substituted Urea Derivatives on Mouse Melanocortin Receptors. ACS Chem Neurosci 2016; 7:196-205. [PMID: 26645732 DOI: 10.1021/acschemneuro.5b00273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The melanocortin system is involved in the regulation of several complex physiological functions. In particular, the melanocortin-3 and -4 receptors (MC3R/MC4R) have been demonstrated to regulate body weight, energy homeostasis, and feeding behavior. Synthetic and endogenous melanocortin agonists have been shown to be anorexigenic in rodent models. Herein, we report synthesis and structure-activity relationship (SAR) studies of 27 nonpeptide small molecule ligands based on an unsymmetrical substituted urea core. Three templates containing key residues from the lead compounds, showing diversity at three positions (R(1), R(2), R(3)), were designed and synthesized. The syntheses were optimized for efficient microwave-assisted chemistry that significantly reduced total syntheses time compared to a previously reported room temperature method. The pharmacological characterization of the compounds on the mouse melanocortin receptors identified compounds 1 and 12 with full agonist activity at the mMC4R, but no activity was observed at the mMC3R when tested up to 100 μM concentrations. The SAR identified compounds possessing aliphatic or saturated cyclic amines at the R(1) position, bulky aromatic groups at the R(2) position, and benzyl group at the R(3) position resulted in mMC4R selectivity over the mMC3R. The small molecule template and SAR knowledge from this series may be helpful in further design of MC3R/MC4R selective small molecule ligands.
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Affiliation(s)
- Anamika Singh
- Department
of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department
of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Johannes Kast
- Department
of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Marvin L. S. Dirain
- Department
of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Huisuo Huang
- Department
of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
| | - Carrie Haskell-Luevano
- Department
of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department
of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville, Florida 32610, United States
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16
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Rational, computer-enabled peptide drug design: principles, methods, applications and future directions. Future Med Chem 2015; 7:2173-93. [PMID: 26510691 DOI: 10.4155/fmc.15.142] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Peptides provide promising templates for developing drugs to occupy a middle space between small molecules and antibodies and for targeting 'undruggable' intracellular protein-protein interactions. Importantly, rational or in cerebro design, especially when coupled with validated in silico tools, can be used to efficiently explore chemical space and identify islands of 'drug-like' peptides to satisfy diverse drug discovery program objectives. Here, we consider the underlying principles of and recent advances in rational, computer-enabled peptide drug design. In particular, we consider the impact of basic physicochemical properties, potency and ADME/Tox opportunities and challenges, and recently developed computational tools for enabling rational peptide drug design. Key principles and practices are spotlighted by recent case studies. We close with a hypothetical future case study.
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17
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Montero-Melendez T, Gobbetti T, Cooray SN, Jonassen TEN, Perretti M. Biased agonism as a novel strategy to harness the proresolving properties of melanocortin receptors without eliciting melanogenic effects. THE JOURNAL OF IMMUNOLOGY 2015; 194:3381-8. [PMID: 25725103 DOI: 10.4049/jimmunol.1402645] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
There is a need for novel approaches to control pathologies with overexuberant inflammatory reactions. Targeting melanocortin (MC) receptors represents a promising therapy for obesity and chronic inflammation, but lack of selectivity and safety concerns limit development. A new way to increase selectivity of biological effects entails the identification of biased agonists. In this study, we characterize the small molecule AP1189 as a biased agonist at receptors MC1 and MC3. Although not provoking canonical cAMP generation, AP1189 addition to MC1 or MC3, but not empty vector, transfected HEK293 cells caused ERK1/2 phosphorylation, a signaling responsible for the proefferocytic effect evoked in mouse primary macrophages. Added to macrophage cultures, AP1189 reduced cytokine release, an effect reliant on both MC1 and MC3 as evident from the use of Mc1r(-/-) and Mc3r(-/-) macrophages. No melanogenesis was induced by AP1189 in B16-F10 melanocytes. In vivo, oral AP1189 elicited anti-inflammatory actions in peritonitis and, upon administration at the peak of inflammation, accelerated the resolution phase by ∼3-fold. Finally, given the clinical efficacy of adrenocorticotropin in joint diseases, AP1189 was tested in experimental inflammatory arthritis, where this biased agonist afforded significant reduction of macroscopic and histological parameters of joint disruption. These proof-of-concept analyses with AP1189, an active oral anti-inflammatory and resolution-promoting compound, indicate that biased agonism at MC receptors is an innovative, viable approach to yield novel anti-inflammatory molecules endowed with a more favorable safety profile.
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Affiliation(s)
- Trinidad Montero-Melendez
- William Harvey Research Institute, Barts and The London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom; and
| | - Thomas Gobbetti
- William Harvey Research Institute, Barts and The London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom; and
| | - Sadani N Cooray
- William Harvey Research Institute, Barts and The London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom; and
| | - Thomas E N Jonassen
- Department of Biomedical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - Mauro Perretti
- William Harvey Research Institute, Barts and The London School of Medicine, Queen Mary University of London, London EC1M 6BQ, United Kingdom; and
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18
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Abstract
Although anti-inflammatory drugs are among the most common class of marketed drugs, chronic inflammatory conditions such as rheumatoid arthritis, multiple sclerosis or inflammatory bowel disease still represent unmet needs. New first-in-class drugs might be discovered in the future but the repurpose and further development of old drugs also offers promise for these conditions. This is the case of the melanocortin adrenocorticotropin hormone, ACTH, used in patients since 1952 but regarded as the last therapeutic option when other medications, such as glucocorticoids, cannot be used. Better understanding on its physiological and pharmacological mechanisms of actions and new insights on melanocortin receptors biology have revived the interest on rescuing this old and effective drug. ACTH does not only induce cortisol production, as previously assumed, but it also exerts anti-inflammatory actions by targeting melanocortin receptors present on immune cells. The endogenous agonists for these receptors (ACTH, α-, β-, and γ-melanocyte stimulating hormones), are also produced locally by immune cells, indicating the existence of an endogenous anti-inflammatory tissue-protective circuit involving the melanocortin system. These findings suggested that new ACTH-like melanocortin drugs devoid of steroidogenic actions, and hence side effects, could be developed. This review summarizes the actions of ACTH and melanocortin drugs, their role as endogenous pro-resolving mediators, their current clinical use and provides an overview on how recent advances on GPCR functioning may lead to a novel class of drugs.
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