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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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Hernandez CC, Gimenez LE, Cone RD. Automated Patch Clamp Recordings of GPCR-Gated Ion Channels: Targeting the MC4-R/Kir7.1 Potassium Channel Complex. Methods Mol Biol 2024; 2796:229-248. [PMID: 38856905 DOI: 10.1007/978-1-0716-3818-7_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Automated patch clamp recording is a valuable technique in drug discovery and the study of ion channels. It allows for the precise measurement and manipulation of channel currents, providing insights into their function and modulation by drugs or other compounds. The melanocortin 4 receptor (MC4-R) is a G protein-coupled receptor (GPCR) crucial to appetite regulation, energy balance, and body weight. MC4-R signaling is complex and involves interactions with other receptors and neuropeptides in the appetite-regulating circuitry. MC4-Rs, like other GPCRs, are known to modulate ion channels such as Kir7.1, an inward rectifier potassium channel, in response to ligand binding. This modulation is critical for controlling ion flow across the cell membrane, which can influence membrane potential, excitability, and neurotransmission. The MC4-R is the target for the anti-obesity drug Imcivree. However, this drug is known to lack optimal potency and also has side effects. Using high-throughput techniques for studying the MC4-R/Kir7.1 complex allows researchers to rapidly screen many compounds or conditions, aiding the development of drugs that target this system. Additionally, automated patch clamp recording of this receptor-channel complex and its ligands can provide valuable functional and pharmacological insights supporting the development of novel therapeutic strategies. This approach can be generalized to other GPCR-gated ion channel functional complexes, potentially accelerating the pace of research in different fields with the promise to uncover previously unknown aspects of receptor-ion channel interactions.
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Affiliation(s)
- Ciria C Hernandez
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Center for Chemical Genomics, Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
| | - Luis E Gimenez
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Roger D Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, MI, USA
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3
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Tschöp MH, Friedman JM. Seeking satiety: From signals to solutions. Sci Transl Med 2023; 15:eadh4453. [PMID: 37992155 DOI: 10.1126/scitranslmed.adh4453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 11/03/2023] [Indexed: 11/24/2023]
Abstract
Remedies for the treatment of obesity date to Hippocrates, when patients with obesity were directed to "reduce food and avoid drinking to fullness" and begin "running during the night." Similar recommendations have been repeated ever since, despite the fact that they are largely ineffective. Recently, highly effective therapeutics were developed that may soon enable physicians to manage body weight in patients with obesity in a manner similar to the way that blood pressure is controlled in patients with hypertension. These medicines have grown out of a revolution in our understanding of the molecular and neural control of appetite and body weight, reviewed here.
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Affiliation(s)
- Matthias H Tschöp
- Helmholtz Munich and Technical University Munich, Munich, 85758 Germany
| | - Jeffrey M Friedman
- Laboratory of Molecular Genetics, Howard Hughes Medical Institute, Rockefeller University, New York, NY 10065 USA
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4
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Mainieri F, La Bella S, Rinaldi M, Chiarelli F. Rare genetic forms of obesity in childhood and adolescence, a comprehensive review of their molecular mechanisms and diagnostic approach. Eur J Pediatr 2023; 182:4781-4793. [PMID: 37607976 DOI: 10.1007/s00431-023-05159-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 08/09/2023] [Accepted: 08/10/2023] [Indexed: 08/24/2023]
Abstract
Obesity represents a major health problem in the pediatric population with an increasing prevalence worldwide, associated with cardiovascular and metabolic disorders, and due to both genetic and environmental factors. Rare forms of obesity are mostly monogenic, and less frequently due to polygenic influence. Polygenic form of obesity is usually the common obesity with single gene variations exerting smaller impact on weight and is commonly non-syndromic.Non-syndromic monogenic obesity is associated with variants in single genes typically related to the hypothalamic leptin-melanocortin signalling pathway, which plays a key role in hunger and satiety regulation, thus body weight control. Patients with these genetic defects usually present with hyperphagia and early-onset severe obesity. Significant progress in genetic diagnostic testing has recently made for early identification of patients with genetic obesity, which guarantees prompt intervention in terms of therapeutic management of the disease. What is Known: • Obesity represents a major health problem among children and adolescents, with an increasing prevalence worldwide, associated with cardiovascular disease and metabolic abnormalities, and it can be due to both genetic and environmental factors. • Non-syndromic monogenic obesity is linked to modifications in single genes usually involved in the hypothalamic leptin-melanocortin signalling pathway, which plays a key role in hunger and satiety regulation. What is New: • The increasing understanding of rare forms of monogenic obesity has provided significant insights into the genetic causes of pediatric obesity, and our current knowledge of the various genes associated with childhood obesity is rapidly expanding. • A useful diagnostic algorithm for early identification of genetic obesity has been proposed, which can ensure a prompt intervention in terms of therapeutic management of the disease and an early prevention of the development of associated metabolic conditions.
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Affiliation(s)
| | | | - Marta Rinaldi
- Paediatric Department, Stoke Mandeville Hospital, Thames Valley Deanery, Oxford, UK
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5
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Muratspahić E, Aslanoglou D, White AM, Draxler C, Kozisek X, Farooq Z, Craik DJ, McCormick PJ, Durek T, Gruber CW. Development of Melanocortin 4 Receptor Agonists by Exploiting Animal-Derived Macrocyclic, Disulfide-Rich Peptide Scaffolds. ACS Pharmacol Transl Sci 2023; 6:1373-1381. [PMID: 37854631 PMCID: PMC10580383 DOI: 10.1021/acsptsci.3c00090] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Indexed: 10/20/2023]
Abstract
G protein-coupled receptors are among the most widely studied classes of drug targets. A major challenge in this field is to develop ligands that will selectively modulate a single receptor subtype to overcome the disadvantages of undesired "off target" effects caused by lack of target and thus signaling specificity. In the current study, we explored ligand design for the melanocortin 4 receptor (MC4R) since it is an attractive target for developing antiobesity drugs. Endogenously, the receptor is activated by peptide ligands, i.e., three melanocyte-stimulating hormones (α-MSH, β-MSH, and γ-MSH) and by adrenocorticotropic hormone. Therefore, we utilized a peptide drug design approach, utilizing "molecular grafting" of pharmacophore peptide sequence motifs onto a stable nature-derived peptide scaffold. Specifically, protegrin-4-like-peptide-1 (Pr4LP1) and arenicin-1-like-peptide-1 (Ar3LP1) fully activated MC4R in a functional cAMP assay with potencies of 3.7 and 1.0 nM, respectively. In a nanoluciferase complementation assay with less signal amplification, the designed peptides fully recruited mini-Gs with subnanomolar and nanomolar potencies. Interestingly, these novel peptide MC4R ligands recruited β-arrestin-2 with ∼2-fold greater efficacies and ∼20-fold increased potencies as compared to the endogenous α-MSH. The peptides were inactive at related MC1R and MC3R in a cAMP accumulation assay. These findings highlight the applicability of animal-derived disulfide-rich scaffolds to design pathway and subtype selective MC4R pharmacological probes. In the future, this approach could be exploited to develop functionally selective ligands that could offer safer and more effective obesity drugs.
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Affiliation(s)
- Edin Muratspahić
- Center
for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
- Institute
for Molecular Bioscience, Australian Research Council Centre of Excellence
for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Despoina Aslanoglou
- Department
of Endocrinology, Queen Mary University
of London, London E1 4NS, U.K.
| | - Andrew M. White
- Institute
for Molecular Bioscience, Australian Research Council Centre of Excellence
for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Claudia Draxler
- Center
for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Xaver Kozisek
- Center
for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Zara Farooq
- Department
of Endocrinology, Queen Mary University
of London, London E1 4NS, U.K.
| | - David J. Craik
- Institute
for Molecular Bioscience, Australian Research Council Centre of Excellence
for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Peter J. McCormick
- Department
of Endocrinology, Queen Mary University
of London, London E1 4NS, U.K.
| | - Thomas Durek
- Institute
for Molecular Bioscience, Australian Research Council Centre of Excellence
for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Christian W. Gruber
- Center
for Physiology and Pharmacology, Institute of Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
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6
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Sweeney P, Gimenez LE, Hernandez CC, Cone RD. Targeting the central melanocortin system for the treatment of metabolic disorders. Nat Rev Endocrinol 2023; 19:507-519. [PMID: 37365323 DOI: 10.1038/s41574-023-00855-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/18/2023] [Indexed: 06/28/2023]
Abstract
A large body of preclinical and clinical data shows that the central melanocortin system is a promising therapeutic target for treating various metabolic disorders such as obesity and cachexia, as well as anorexia nervosa. Setmelanotide, which functions by engaging the central melanocortin circuitry, was approved by the FDA in 2020 for use in certain forms of syndromic obesity. Furthermore, the FDA approvals in 2019 of two peptide drugs targeting melanocortin receptors for the treatment of generalized hypoactive sexual desire disorder (bremelanotide) and erythropoietic protoporphyria-associated phototoxicity (afamelanotide) demonstrate the safety of this class of peptides. These approvals have also renewed excitement in the development of therapeutics targeting the melanocortin system. Here, we review the anatomy and function of the melanocortin system, discuss progress and challenges in developing melanocortin receptor-based therapeutics, and outline potential metabolic and behavioural disorders that could be addressed using pharmacological agents targeting these receptors.
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Affiliation(s)
- Patrick Sweeney
- School of Molecular and Cellular Biology, College of Liberal Arts and Sciences, University of Illinois Urbana-Champaign, Champaign, IL, USA
| | - Luis E Gimenez
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | | | - Roger D Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, MI, USA.
- Department of Molecular, Cellular, and Developmental Biology, College of Literature Science and the Arts, University of Michigan, Ann Arbor, MI, USA.
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7
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Scorrano G, La Bella S, Matricardi S, Chiarelli F, Giannini C. Neuroendocrine Effects on the Risk of Metabolic Syndrome in Children. Metabolites 2023; 13:810. [PMID: 37512517 PMCID: PMC10383317 DOI: 10.3390/metabo13070810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
The endocrine and nervous systems reciprocally interact to manage physiological individual functions and homeostasis. The nervous system modulates hormone release through the hypothalamus, the main cerebrally specialized structure of the neuroendocrine system. The hypothalamus is involved in various metabolic processes, administering hormone and neuropeptide release at different levels. This complex activity is affected by the neurons of various cerebral areas, environmental factors, peripheral organs, and mediators through feedback mechanisms. Therefore, neuroendocrine pathways play a key role in metabolic homeostasis control, and their abnormalities are associated with the development of metabolic syndrome (MetS) in children. The impaired functioning of the genes, hormones, and neuropeptides of various neuroendocrine pathways involved in several metabolic processes is related to an increased risk of dyslipidaemia, visceral obesity, insulin resistance, type 2 diabetes mellitus, and hypertension. This review examines the neuroendocrine effects on the risk of MetS in children, identifying and underlying several conditions associated with neuroendocrine pathway disruption. Neuroendocrine systems should be considered in the complex pathophysiology of MetS, and, when genetic or epigenetic mutations in "hot" pathways occur, they could be studied for new potential target therapies in severe and drug-resistant paediatric forms of MetS.
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Affiliation(s)
- Giovanna Scorrano
- Department of Pediatrics, University of Chieti-Pescara, Via Dei Vestini, 66100 Chieti, Italy
| | - Saverio La Bella
- Department of Pediatrics, University of Chieti-Pescara, Via Dei Vestini, 66100 Chieti, Italy
| | - Sara Matricardi
- Department of Pediatrics, University of Chieti-Pescara, Via Dei Vestini, 66100 Chieti, Italy
| | - Francesco Chiarelli
- Department of Pediatrics, University of Chieti-Pescara, Via Dei Vestini, 66100 Chieti, Italy
| | - Cosimo Giannini
- Department of Pediatrics, University of Chieti-Pescara, Via Dei Vestini, 66100 Chieti, Italy
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8
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Millington GWM, Palmer HE. Proopiomelanocortin (POMC) and psychodermatology. SKIN HEALTH AND DISEASE 2023; 3:e201. [PMID: 37275429 PMCID: PMC10233089 DOI: 10.1002/ski2.201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 11/30/2022] [Accepted: 12/13/2022] [Indexed: 06/07/2023]
Abstract
Psychodermatology is the crossover discipline between Dermatology and Clinical Psychology and/or Psychiatry. It encompasses both Psychiatric diseases that present with cutaneous manifestations (such as delusional infestation) or more commonly, the psychiatric or psychological problems associated with skin disease, such as depression associated with psoriasis. These problems may be the result either of imbalance in or be the consequence of alteration in the homoeostatic endocrine mechanisms found in the systemic hypothalamic-pituitary-adrenal axis or in the local cutaneous corticotrophin-releasing factor-proopiomelanocortin-corticosteroid axis. Alteration in either of these systems can lead to immune disruption and worsening of immune dermatoses and vice-versa. These include diseases such as psoriasis, atopic eczema, acne, alopecia areata, vitiligo and melasma, all of which are known to be linked to stress. Similarly, stress and illnesses such as depression are linked with many immunodermatoses and may reflect alterations in the body's central and peripheral neuroendocrine stress pathways. It is important to consider issues pertaining to skin of colour, particularly with pigmentary disorders.
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Affiliation(s)
- George W. M. Millington
- Dermatology DepartmentNorfolk and Norwich University HospitalNorwichUK
- Norwich Medical SchoolNorwichUK
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9
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Wu CLS, Cioanca AV, Gelmi MC, Wen L, Di Girolamo N, Zhu L, Natoli R, Conway RM, Petsoglou C, Jager MJ, McCluskey PJ, Madigan MC. The multifunctional human ocular melanocortin system. Prog Retin Eye Res 2023; 95:101187. [PMID: 37217094 DOI: 10.1016/j.preteyeres.2023.101187] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 05/12/2023] [Accepted: 05/12/2023] [Indexed: 05/24/2023]
Abstract
Immune privilege in the eye involves physical barriers, immune regulation and secreted proteins that together limit the damaging effects of intraocular immune responses and inflammation. The neuropeptide alpha-melanocyte stimulating hormone (α-MSH) normally circulates in the aqueous humour of the anterior chamber and the vitreous fluid, secreted by iris and ciliary epithelium, and retinal pigment epithelium (RPE). α-MSH plays an important role in maintaining ocular immune privilege by helping the development of suppressor immune cells and by activating regulatory T-cells. α-MSH functions by binding to and activating melanocortin receptors (MC1R to MC5R) and receptor accessory proteins (MRAPs) that work in concert with antagonists, otherwise known as the melanocortin system. As well as controlling immune responses and inflammation, a broad range of biological functions is increasingly recognised to be orchestrated by the melanocortin system within ocular tissues. This includes maintaining corneal transparency and immune privilege by limiting corneal (lymph)angiogenesis, sustaining corneal epithelial integrity, protecting corneal endothelium and potentially enhancing corneal graft survival, regulating aqueous tear secretion with implications for dry eye disease, facilitating retinal homeostasis via maintaining blood-retinal barriers, providing neuroprotection in the retina, and controlling abnormal new vessel growth in the choroid and retina. The role of melanocortin signalling in uveal melanocyte melanogenesis however remains unclear compared to its established role in skin melanogenesis. The early application of a melanocortin agonist to downregulate systemic inflammation used adrenocorticotropic hormone (ACTH)-based repository cortisone injection (RCI), but adverse side effects including hypertension, edema, and weight gain, related to increased adrenal gland corticosteroid production, impacted clinical uptake. Compared to ACTH, melanocortin peptides that target MC1R, MC3R, MC4R and/or MC5R, but not adrenal gland MC2R, induce minimal corticosteroid production with fewer amdverse systemic effects. Pharmacological advances in synthesising MCR-specific targeted peptides provide further opportunities for treating ocular (and systemic) inflammatory diseases. Following from these observations and a renewed clinical and pharmacological interest in the diverse biological roles of the melanocortin system, this review highlights the physiological and disease-related involvement of this system within human eye tissues. We also review the emerging benefits and versatility of melanocortin receptor targeted peptides as non-steroidal alternatives for inflammatory eye diseases such as non-infectious uveitis and dry eye disease, and translational applications in promoting ocular homeostasis, for example, in corneal transplantation and diabetic retinopathy.
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Affiliation(s)
- Chieh-Lin Stanley Wu
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, Australia; Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; Department of Optometry, Asia University, Taichung, Taiwan
| | - Adrian V Cioanca
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; John Curtin School of Medical Research, The Australian National University, ACT, Australia; ANU Medical School, The Australian National University, ACT, Australia
| | - Maria C Gelmi
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Li Wen
- New South Wales Organ and Tissue Donation Service, Sydney Hospital and Sydney Eye Hospital, NSW, 2000, Australia
| | - Nick Di Girolamo
- School of Biomedical Sciences, Mechanisms of Disease and Translational Research, University of New South Wales, Sydney, Australia
| | - Ling Zhu
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Riccardo Natoli
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; John Curtin School of Medical Research, The Australian National University, ACT, Australia; ANU Medical School, The Australian National University, ACT, Australia
| | - R Max Conway
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Constantinos Petsoglou
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; New South Wales Organ and Tissue Donation Service, Sydney Hospital and Sydney Eye Hospital, NSW, 2000, Australia
| | - Martine J Jager
- Department of Ophthalmology, Leiden University Medical Centre, Leiden, the Netherlands
| | - Peter J McCluskey
- Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Michele C Madigan
- School of Optometry and Vision Science, Faculty of Medicine and Health, University of New South Wales, Sydney, Australia; Save Sight Institute and Ophthalmology, The Faculty of Medicine and Health, The University of Sydney, Sydney, Australia.
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10
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Markov DD, Dolotov OV, Grivennikov IA. The Melanocortin System: A Promising Target for the Development of New Antidepressant Drugs. Int J Mol Sci 2023; 24:ijms24076664. [PMID: 37047638 PMCID: PMC10094937 DOI: 10.3390/ijms24076664] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/05/2023] Open
Abstract
Major depression is one of the most prevalent mental disorders, causing significant human suffering and socioeconomic loss. Since conventional antidepressants are not sufficiently effective, there is an urgent need to develop new antidepressant medications. Despite marked advances in the neurobiology of depression, the etiology and pathophysiology of this disease remain poorly understood. Classical and newer hypotheses of depression suggest that an imbalance of brain monoamines, dysregulation of the hypothalamic-pituitary-adrenal axis (HPAA) and immune system, or impaired hippocampal neurogenesis and neurotrophic factors pathways are cause of depression. It is assumed that conventional antidepressants improve these closely related disturbances. The purpose of this review was to discuss the possibility of affecting these disturbances by targeting the melanocortin system, which includes adrenocorticotropic hormone-activated receptors and their peptide ligands (melanocortins). The melanocortin system is involved in the regulation of various processes in the brain and periphery. Melanocortins, including peripherally administered non-corticotropic agonists, regulate HPAA activity, exhibit anti-inflammatory effects, stimulate the levels of neurotrophic factors, and enhance hippocampal neurogenesis and neurotransmission. Therefore, endogenous melanocortins and their analogs are able to complexly affect the functioning of those body’s systems that are closely related to depression and the effects of antidepressants, thereby demonstrating a promising antidepressant potential.
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Affiliation(s)
- Dmitrii D. Markov
- National Research Center “Kurchatov Institute”, Kurchatov Sq. 2, 123182 Moscow, Russia
| | - Oleg V. Dolotov
- National Research Center “Kurchatov Institute”, Kurchatov Sq. 2, 123182 Moscow, Russia
- Faculty of Biology, Lomonosov Moscow State University, Leninskie Gory, 119234 Moscow, Russia
| | - Igor A. Grivennikov
- National Research Center “Kurchatov Institute”, Kurchatov Sq. 2, 123182 Moscow, Russia
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11
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Garnsey MR, Smith AC, Polivkova J, Arons AL, Bai G, Blakemore C, Boehm M, Buzon LM, Campion SN, Cerny M, Chang SC, Coffman K, Farley KA, Fonseca KR, Ford KK, Garren J, Kong JX, Koos MRM, Kung DW, Lian Y, Li MM, Li Q, Martinez-Alsina LA, O'Connor R, Ogilvie K, Omoto K, Raymer B, Reese MR, Ryder T, Samp L, Stevens KA, Widlicka DW, Yang Q, Zhu K, Fortin JP, Sammons MF. Discovery of the Potent and Selective MC4R Antagonist PF-07258669 for the Potential Treatment of Appetite Loss. J Med Chem 2023; 66:3195-3211. [PMID: 36802610 DOI: 10.1021/acs.jmedchem.2c02012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The melanocortin-4 receptor (MC4R) is a centrally expressed, class A GPCR that plays a key role in the regulation of appetite and food intake. Deficiencies in MC4R signaling result in hyperphagia and increased body mass in humans. Antagonism of MC4R signaling has the potential to mitigate decreased appetite and body weight loss in the setting of anorexia or cachexia due to underlying disease. Herein, we report on the identification of a series of orally bioavailable, small-molecule MC4R antagonists using a focused hit identification effort and the optimization of these antagonists to provide clinical candidate 23. Introduction of a spirocyclic conformational constraint allowed for simultaneous optimization of MC4R potency and ADME attributes while avoiding the production of hERG active metabolites observed in early series leads. Compound 23 is a potent and selective MC4R antagonist with robust efficacy in an aged rat model of cachexia and has progressed into clinical trials.
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Affiliation(s)
| | - Aaron C Smith
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Jana Polivkova
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Autumn L Arons
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Guoyun Bai
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | - Markus Boehm
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Leanne M Buzon
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Sarah N Campion
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Matthew Cerny
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Shiao-Chi Chang
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Karen Coffman
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | - Kari R Fonseca
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Kristen K Ford
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Jeonifer Garren
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Jimmy X Kong
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Martin R M Koos
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Daniel W Kung
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Yajing Lian
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Monica M Li
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Qifang Li
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | | | - Kevin Ogilvie
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Kiyoyuki Omoto
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Brian Raymer
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Matthew R Reese
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Tim Ryder
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | - Lacey Samp
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
| | | | | | - Qingyi Yang
- Pfizer, Incorporated, Cambridge, Massachusetts 02139, United States
| | - Kaicheng Zhu
- Pfizer, Incorporated, Groton, Connecticut 06340, United States
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12
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Yue WK, Zhang T, Shandre Mugan R, Barlow N, Chalmers DK, Pouton CW, Thompson PE. Targeting Melanocortin Receptors Using S NAr-Type Macrocyclization: A Doubly Orthogonal Route to Cyclic Peptide Conjugates. J Med Chem 2023; 66:3273-3283. [PMID: 36808973 DOI: 10.1021/acs.jmedchem.2c01587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
While a range of strategies exist to accomplish peptide macrocyclization, they are frequently limited by the need for orthogonal protection or provide little opportunity for structural diversification. We have evaluated an efficient macrocyclization method that employs nucleophilic aromatic substitution (SNAr) to create thioether macrocycles. This versatile macrocyclization, orthogonal to conventional peptide synthesis, can be performed in solution on unprotected peptidomimetics or on resin-bound peptides with side-chain protection in place. We show that the electron-withdrawing groups present in the products can be further utilized in subsequent orthogonal reactions to alter the peptide properties or to add prosthetic groups. The macrocyclization strategy was applied to the design of melanocortin ligands, generating a library of potent melanocortin agonists that exhibit distinct subtype selectivity.
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Affiliation(s)
- Wenxiao K Yue
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Tianxia Zhang
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Rekha Shandre Mugan
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Nicholas Barlow
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - David K Chalmers
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Colin W Pouton
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Philip E Thompson
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
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13
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Hernandez CC, Gimenez LE, Dahir NS, Peisley A, Cone RD. The unique structural characteristics of the Kir 7.1 inward rectifier potassium channel: a novel player in energy homeostasis control. Am J Physiol Cell Physiol 2023; 324:C694-C706. [PMID: 36717105 PMCID: PMC10026989 DOI: 10.1152/ajpcell.00335.2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 02/01/2023]
Abstract
The inward rectifier potassium channel Kir7.1, encoded by the KCNJ13 gene, is a tetramer composed of two-transmembrane domain-spanning monomers, closer in homology to Kir channels associated with potassium transport such as Kir1.1, 1.2, and 1.3. Compared with other channels, Kir7.1 exhibits small unitary conductance and low dependence on external potassium. Kir7.1 channels also show a phosphatidylinositol 4,5-bisphosphate (PIP2) dependence for opening. Accordingly, retinopathy-associated Kir7.1 mutations mapped at the binding site for PIP2 resulted in channel gating defects leading to channelopathies such as snowflake vitreoretinal degeneration and Leber congenital amaurosis in blind patients. Lately, this channel's role in energy homeostasis was reported due to the direct interaction with the melanocortin type 4 receptor (MC4R) in the hypothalamus. As this channel seems to play a multipronged role in potassium homeostasis and neuronal excitability, we will discuss what is predicted from a structural viewpoint and its possible implications for hunger control.
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Affiliation(s)
- Ciria C Hernandez
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States
| | - Luis E Gimenez
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States
| | - Naima S Dahir
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States
| | - Alys Peisley
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States
| | - Roger D Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, United States
- Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States
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14
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Vyunova TV, Andreeva LA, Shevchenko KV, Glazova NY, Sebentsova EA, Levitskaya NG, Myasoedov NF. Synthetic corticotropins and the GABA-receptor system: Direct and delayed effects. Chem Biol Drug Des 2023; 101:1393-1405. [PMID: 36828803 DOI: 10.1111/cbdd.14221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 01/16/2023] [Accepted: 02/13/2023] [Indexed: 02/26/2023]
Abstract
The central effectors of the stress system are greatly interconnected and include, among others, a large group of peptides derived from proopiomelanocortin. In addition to natural corticotropins, a number of artificial molecules that contain some ACTH fragments in their structure are also referred to members of this family. Some of them possess a wide range of biological activity. The molecular mechanism underlying the biological activity of such peptides is partly based on allosteric modulation of various receptors. We analyzed the ability of some biologically active synthetic corticotropins (ACTH(4-7)PGP, ACTH(6-9)PGP, ACTH(7-10)PGP), and glyproline PGPL to affect the GABA-receptor system of rat brain. The effects of the peptides were studied in the isolated plasma membranes of brain cells, as well as after systemic peptide administration in the rat model of acute restraint stress. The delayed effect of stress or preadministration of each of the studied peptides on [3 H]GABA binding was different for its high- and low-affinity-specific sites. The studied peptides individually affected the binding of [3 H]GABA in their own way. Acute restraint stress caused a decrease in [3 H]GABA binding at its low-affine site and did not affected the high-affine site. Preliminary peptide administration did not influence this effect of stress.
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Affiliation(s)
- Tatiana V Vyunova
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia
| | - Ludmila A Andreeva
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia
| | - Konstantin V Shevchenko
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia
| | - Nataliya Yu Glazova
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia.,Faculty of Biology, Moscow State University, Moscow, Russia
| | - Elena A Sebentsova
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia.,Faculty of Biology, Moscow State University, Moscow, Russia
| | - Natalia G Levitskaya
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia.,Faculty of Biology, Moscow State University, Moscow, Russia
| | - Nikolay F Myasoedov
- Institute of Molecular Genetics of National Research Centre «Kurchatov Institute», Moscow, Russia.,The Mental Health Research Center of the Russian Academy of Medical Sciences, Moscow, Russia
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15
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Dodd J, Jordan R, Makhlina M, Barnett K, Roffel A, Spana C, Obr A, Dhingra P, Kayne PS. A novel oral formulation of the melanocortin-1 receptor agonist PL8177 resolves inflammation in preclinical studies of inflammatory bowel disease and is gut restricted in rats, dogs, and humans. Front Immunol 2023; 14:1083333. [PMID: 36891301 PMCID: PMC9986545 DOI: 10.3389/fimmu.2023.1083333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 01/31/2023] [Indexed: 02/22/2023] Open
Abstract
Introduction PL8177 is a potent and selective agonist of the melanocortin 1 receptor (MC1R). PL8177 has shown efficacy in reversing intestinal inflammation in a cannulated rat ulcerative colitis model. To facilitate oral delivery, a novel, polymer-encapsulated formulation of PL8177 was developed. This formulation was tested in 2 rat ulcerative colitis models and evaluated for distribution, in vivo, in rats, dogs, and humans. Methods The rat models of colitis were induced by treatment with 2,4-dinitrobenzenesulfonic acid or dextran sulfate sodium. Single nuclei RNA sequencing of colon tissues was performed to characterize the mechanism of action. The distribution and concentration of PL8177 and the main metabolite within the GI tract after a single oral dose of PL8177 was investigated in rats and dogs. A phase 0 clinical study using a single microdose (70 µg) of [14C]-labeled PL8177 investigated the release of PL8177 in the colon of healthy men after oral administration. Results Rats treated with 50 µg oral PL8177 demonstrated significantly lower macroscopic colon damage scores and improvement in colon weight, stool consistency, and fecal occult blood vs the vehicle without active drug. Histopathology analysis resulted in the maintenance of intact colon structure and barrier, reduced immune cell infiltration, and increased enterocytes with PL8177 treatment. Transcriptome data show that oral PL8177 50 µg treatment causes relative cell populations and key gene expressions levels to move closer to healthy controls. Compared with vehicle, treated colon samples show negative enrichment of immune marker genes and diverse immune-related pathways. In rats and dogs, orally administered PL8177 was detected at higher amounts in the colon vs upper GI tract. [14C]-PL8177 and the main metabolite were detected in the feces but not in the plasma and urine in humans. This suggests that the parent drug [14C]-PL8177 was released from the polymer formulation and metabolized within the GI tract, where it would be expected to exert its effect. Conclusion Collectively, these findings support further research into the oral formulation of PL8177 as a possible therapeutic for GI inflammatory diseases in humans.
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Affiliation(s)
- John Dodd
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | - Robert Jordan
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | | | - Keith Barnett
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | - Ad Roffel
- Consulting & Advisory Services - Clinical Pharmacology, ICON plc, Groningen, Netherlands
| | - Carl Spana
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | - Alison Obr
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | | | - Paul S Kayne
- Palatin Technologies, Inc., Cranbury, NJ, United States
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16
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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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17
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White AM, Dellsén A, Larsson N, Kaas Q, Jansen F, Plowright AT, Knerr L, Durek T, Craik DJ. Late-Stage Functionalization with Cysteine Staples Generates Potent and Selective Melanocortin Receptor-1 Agonists. J Med Chem 2022; 65:12956-12969. [PMID: 36167503 DOI: 10.1021/acs.jmedchem.2c00793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, cysteine staples were used as a late-stage functionalization strategy to diversify peptides and build conjugates targeting the melanocortin G-protein-coupled receptors [melanocortin receptor-1 (MC1R) and MC3R-MC5R]. Monocyclic and bicyclic agonists based on sunflower trypsin inhibitor-1 were used to generate a selection of stapled peptides that were evaluated for binding (pKi) and functional activation (pEC50) of the melanocortin receptor subtypes. Stapled peptides generally had improved activity, with aromatic stapled peptides yielding selective MC1R agonists, including a xylene-stapled peptide (2) with an EC50 of 1.9 nM for MC1R and >150-fold selectivity for MC3R and MC4R. Selected stapled peptides were further functionalized with linkers and payloads, generating a series of conjugated peptides with potent MC1R activity, including one pyridazine-functionalized peptide (21) with picomolar activity at MC1R (Ki 58 pM; EC50 < 9 pM). This work demonstrates that staples can be used as modular synthetic tools to tune potency and selectivity in peptide-based drug design.
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Affiliation(s)
- Andrew M White
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Anita Dellsén
- Mechanistic Biology & Profiling, Discovery Sciences, R&D, AstraZeneca, Gothenburg 43183, Sweden
| | - Niklas Larsson
- Discovery Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg 43183, Sweden
| | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Frank Jansen
- Mechanistic Biology & Profiling, Discovery Sciences, R&D, AstraZeneca, Gothenburg 43183, Sweden
| | - Alleyn T Plowright
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg 43183, Sweden
| | - Laurent Knerr
- Medicinal Chemistry, Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg 43183, Sweden
| | - Thomas Durek
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David J Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, Queensland 4072, Australia
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18
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Liu Z, Hruby VJ. MC4R biased signalling and the conformational basis of biological function selections. J Cell Mol Med 2022; 26:4125-4136. [PMID: 35818295 PMCID: PMC9344818 DOI: 10.1111/jcmm.17441] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 05/26/2022] [Accepted: 06/01/2022] [Indexed: 11/30/2022] Open
Abstract
The MC4R, a GPCR, has long been a major target for obesity treatment. As the most well‐studied melanocortin receptor subtype, the evolutionary knowledge pushes the drug development and structure–activity relationship (SAR) moving forward. The past decades have witnessed the evolution of scientists' view on GPCRs gradually from the control of a single canonical signalling pathway via a bilateral ‘active‐inactive’ model to a multi‐state alternative model where the ligands' binding affects the selection of the downstream signalling. This evolution brings the concept of biased signalling and the beginning of the next generation of peptide drug development, with the aim of turning from receptor subtype specificity to signalling pathway selectivity. The determination of the value structures of the MC4R revealed insights into the working mechanism of MC4R activation upon binding of agonists. However, new challenge has risen as we seek to unravel the mystery of MC4R signalling selection. Thus, more biased agonists and ligands with representative biological functions are needed to solve the rest of the puzzle.
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Affiliation(s)
- Zekun Liu
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona, USA
| | - Victor J Hruby
- Department of Chemistry and Biochemistry, The University of Arizona, Tucson, Arizona, USA
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19
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The neurobiology of bremelanotide for the treatment of hypoactive sexual desire disorder in premenopausal women. CNS Spectr 2022; 27:281-289. [PMID: 33455598 DOI: 10.1017/s109285292100002x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Hypoactive sexual desire disorder (HSDD) is a common female sexual dysfunction and is estimated to affect approximately 10% of women in the United States. It has been suggested that HSDD is associated with an imbalance of hormone and neurotransmitter levels in the brain, resulting in decreased excitation, increased inhibition, or a combination of both. Evidence suggests neurotransmitters, including dopamine (DA), norepinephrine, and serotonin, as well as hormones such as estradiol and testosterone, contribute to female sexual desire and response. Current treatments for HSDD include psychotherapy, and two US Food and Drug Administration-approved medications for premenopausal women: flibanserin, a serotonin mixed agonist and antagonist, and bremelanotide, a melanocortin receptor (MCR) agonist. Melanocortins are endogenous neuropeptides associated with the excitatory pathway of the female sexual response system. MCRs are found throughout the body, including the brain. Bremelanotide is an MCR agonist that nonselectively activates several of the receptor subtypes, of which subtype 4 (MC4R) is the most relevant at therapeutic doses. MC4R is predominantly expressed in the medial preoptic area (mPOA) of the hypothalamus in the brain, and is important for female sexual function. Animal studies suggest that bremelanotide may affect female sexual desire by activating presynaptic MC4Rs on neurons in the mPOA of the hypothalamus, leading to increased release of DA, an excitatory neurotransmitter that increases sexual desire. This review presents what is known about the mechanism of action of bremelanotide in the context of treating HSDD.
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20
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Webber T, Ronacher K, Conradie-Smit M, Kleynhans L. Interplay Between the Immune and Endocrine Systems in the Lung: Implications for TB Susceptibility. Front Immunol 2022; 13:829355. [PMID: 35273609 PMCID: PMC8901994 DOI: 10.3389/fimmu.2022.829355] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 02/02/2022] [Indexed: 12/25/2022] Open
Abstract
The role of the endocrine system on the immune response, especially in the lung, remains poorly understood. Hormones play a crucial role in the development, homeostasis, metabolism, and response to the environment of cells and tissues. Major infectious and metabolic diseases, such as tuberculosis and diabetes, continue to converge, necessitating the development of a clearer understanding of the immune and endocrine interactions that occur in the lung. Research in bacterial respiratory infections is at a critical point, where the limitations in identifying and developing antibiotics is becoming more profound. Hormone receptors on alveolar and immune cells may provide a plethora of targets for host-directed therapy. This review discusses the interactions between the immune and endocrine systems in the lung. We describe hormone receptors currently identified in the lungs, focusing on the effect hormones have on the pulmonary immune response. Altered endocrine responses in the lung affect the balance between pro- and anti-inflammatory immune responses and play a role in the response to infection in the lung. While some hormones, such as leptin, resistin and lipocalin-2 promote pro-inflammatory responses and immune cell infiltration, others including adiponectin and ghrelin reduce inflammation and promote anti-inflammatory cell responses. Furthermore, type 2 diabetes as a major endocrine disease presents with altered immune responses leading to susceptibility to lung infections, such as tuberculosis. A better understanding of these interactions will expand our knowledge of the mechanisms at play in susceptibility to infectious diseases and may reveal opportunities for the development of host-directed therapies.
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Affiliation(s)
- Tariq Webber
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Katharina Ronacher
- Translational Research Institute, Mater Research Institute - The University of Queensland, Brisbane, QLD, Australia
| | - Marli Conradie-Smit
- Division of Endocrinology, Department of Medicine, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Léanie Kleynhans
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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21
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Daoussis D, Kordas P, Varelas G, Michalaki M, Onoufriou A, Mamali I, Iliopoulos G, Melissaropoulos K, Ntelis K, Velissaris D, Tzimas G, Georgiou P, Vamvakopoulou S, Paliogianni F, Andonopoulos AP, Georgopoulos N. ACTH vs steroids for the treatment of acute gout in hospitalized patients: a randomized, open label, comparative study. Rheumatol Int 2022; 42:949-958. [PMID: 35445840 DOI: 10.1007/s00296-022-05128-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 03/25/2022] [Indexed: 11/26/2022]
Abstract
The management of acute gout in the hospital setting may be challenging since most patients are elderly with multiple unstable comorbidities. However, there are no prospective clinical trials for hospitalized patients with gout to guide optimal management. Evidence indicates that steroids or adrenocorticotropic hormone (ACTH) may be effective and safe therapeutic options for these patients. This study aimed at directly comparing the efficacy and safety of ACTH vs betamethasone for the treatment of gout in hospitalized patients. This is the first prospective clinical trial for hospitalized patients with gout. We designed a randomized, open label study to assess the efficacy and safety of a single intramuscular injection of either ACTH or betamethasone in hospitalized patients with acute gout. Primary efficacy endpoints were the change in intensity of pain as recorded using a Visual Analogue Scale (VAS) at baseline compared to 24 h (ΔVAS24h), and 48 h. Moreover, we assessed safety and effects on the hypothalamic-pituitary-adrenal (HPA) axis, glucose and lipid homeostasis, bone metabolism, electrolytes and renal function. 38 patients were recruited. Both treatments were highly effective. The mean ± SE ΔVAS24h and ΔVAS48h for ACTH was 4.48 ± 0.29 and 5.58 ± 0.26, respectively. The mean ± SE ΔVAS24h and ΔVAS48h for betamethasone was 4.67 ± 0.32 and 5.67 ± 0.28, respectively. Direct comparison between the two groups at 24 h and 48 h did not show statistically significant differences. Both treatments were well tolerated and safe. The effects on all metabolic parameters were mostly minimal and transient for both treatments. However, ACTH may affect less the HPA axis and bone metabolism compared to betamethasone, thus leading to the conclusion that. ACTH and betamethasone are effective and safe for the management of acute gout in hospitalized patients but that ACTH may associate with less disturbance of the HPA axis and bone metabolism. Our data support the use of both drugs as first line treatments for hospitalized patients with gout.Clinical trial registration: ClinicalTrials.gov NCT04306653.
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Affiliation(s)
- Dimitrios Daoussis
- Department of Rheumatology, Patras University Hospital, University of Patras Medical School, Patras, Greece.
| | | | - George Varelas
- Data and Media Lab, Department of Electrical and Computer Engineering, University of Peloponnese, Tripoli, Greece
| | - Marina Michalaki
- Department of Endocrinology, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | - Anny Onoufriou
- Department of Microbiology, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | - Irene Mamali
- Department of Endocrinology, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | - George Iliopoulos
- Department of Rheumatology, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | | | | | - Dimitrios Velissaris
- Department of Internal Medicine, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | - Giannis Tzimas
- Data and Media Lab, Department of Electrical and Computer Engineering, University of Peloponnese, Tripoli, Greece
| | | | - Sofia Vamvakopoulou
- Department of Microbiology, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | - Fotini Paliogianni
- Department of Microbiology, Patras University Hospital, University of Patras Medical School, Patras, Greece
| | | | - Neoklis Georgopoulos
- Department of Endocrinology, Patras University Hospital, University of Patras Medical School, Patras, Greece
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22
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Tomassi S, Dimmito MP, Cai M, D’Aniello A, Del Bene A, Messere A, Liu Z, Zhu T, Hruby VJ, Stefanucci A, Cosconati S, Mollica A, Di Maro S. CLIPSing Melanotan-II to Discover Multiple Functionally Selective hMCR Agonists. J Med Chem 2022; 65:4007-4017. [DOI: 10.1021/acs.jmedchem.1c01848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Stefano Tomassi
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Via D. Montesano 49, Naples 80131, Italy
| | - Marilisa Pia Dimmito
- Dipartimento di Farmacia, Università di Chieti-Pescara “G. d’Annunzio”, Via dei Vestini 31, Chieti 66100, Italy
| | - Minying Cai
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Antonia D’Aniello
- DiSTABiF, University of Campania “Luigi Vanvitelli”, Via Vivaldi 43, 81100 Caserta, Italy
| | - Alessandra Del Bene
- DiSTABiF, University of Campania “Luigi Vanvitelli”, Via Vivaldi 43, 81100 Caserta, Italy
| | - Anna Messere
- DiSTABiF, University of Campania “Luigi Vanvitelli”, Via Vivaldi 43, 81100 Caserta, Italy
| | - Zekun Liu
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Tingyi Zhu
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Victor J. Hruby
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Azzurra Stefanucci
- Dipartimento di Farmacia, Università di Chieti-Pescara “G. d’Annunzio”, Via dei Vestini 31, Chieti 66100, Italy
| | - Sandro Cosconati
- DiSTABiF, University of Campania “Luigi Vanvitelli”, Via Vivaldi 43, 81100 Caserta, Italy
| | - Adriano Mollica
- Dipartimento di Farmacia, Università di Chieti-Pescara “G. d’Annunzio”, Via dei Vestini 31, Chieti 66100, Italy
| | - Salvatore Di Maro
- DiSTABiF, University of Campania “Luigi Vanvitelli”, Via Vivaldi 43, 81100 Caserta, Italy
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23
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Translational advances of melanocortin drugs: Integrating biology, chemistry and genetics. Semin Immunol 2022; 59:101603. [PMID: 35341670 DOI: 10.1016/j.smim.2022.101603] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 03/10/2022] [Accepted: 03/15/2022] [Indexed: 01/15/2023]
Abstract
Melanocortin receptors have emerged as important targets with a very unusual versatility, as their widespread distribution on multiple tissues (e.g. skin, adrenal glands, brain, immune cells, exocrine glands) together with the variety of physiological processes they control (pigmentation, cortisol release, satiety mechanism, inflammation, secretions), place this family of receptors as genuine therapeutic targets for many disorders. This review focuses in the journey of the development of melanocortin receptors as therapeutic targets from the discovery of their existence in the early 1990 s to the approval of the first few drugs of this class. Two major areas of development characterise the current state of melanocortin drug development: their role in obesity, recently culminated with the approval of setmelanotide, and their potential for the treatment of chronic inflammatory and autoimmune diseases like rheumatoid arthritis, multiple sclerosis or fibrosis. The pro-resolving nature of these drugs offers the advantage of acting by mimicking the way our body naturally resolves inflammation, expecting fewer side effects and a more balanced (i.e. non-immunosuppressive) response from them. Here we also review the approaches followed for the design and development of novel compounds, the importance of the GPCR nature of these receptors in the process of drug development, therapeutic value, current challenges and successes, and the potential for the implementation of precision medicine approaches through the incorporation of genetics advances.
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24
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Liu T, Ji RL, Tao YX. Naturally occurring mutations in G protein-coupled receptors associated with obesity and type 2 diabetes mellitus. Pharmacol Ther 2021; 234:108044. [PMID: 34822948 DOI: 10.1016/j.pharmthera.2021.108044] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 11/15/2021] [Accepted: 11/15/2021] [Indexed: 12/12/2022]
Abstract
G protein-coupled receptors (GPCRs) are the largest family of membrane receptors involved in the regulation of almost all known physiological processes. Dysfunctions of GPCR-mediated signaling have been shown to cause various diseases. The prevalence of obesity and type 2 diabetes mellitus (T2DM), two strongly associated disorders, is increasing worldwide, with tremendous economical and health burden. New safer and more efficacious drugs are required for successful weight reduction and T2DM treatment. Multiple GPCRs are involved in the regulation of energy and glucose homeostasis. Mutations in these GPCRs contribute to the development and progression of obesity and T2DM. Therefore, these receptors can be therapeutic targets for obesity and T2DM. Indeed some of these receptors, such as melanocortin-4 receptor and glucagon-like peptide 1 receptor, have provided important new drugs for treating obesity and T2DM. This review will focus on the naturally occurring mutations of several GPCRs associated with obesity and T2DM, especially incorporating recent large genomic data and insights from structure-function studies, providing leads for future investigations.
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Affiliation(s)
- Ting Liu
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States
| | - Ren-Lei Ji
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States
| | - Ya-Xiong Tao
- Department of Anatomy, Physiology and Pharmacology, Auburn University College of Veterinary Medicine, Auburn, AL 36849, United States.
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25
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Structures of active melanocortin-4 receptor-Gs-protein complexes with NDP-α-MSH and setmelanotide. Cell Res 2021; 31:1176-1189. [PMID: 34561620 PMCID: PMC8563958 DOI: 10.1038/s41422-021-00569-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 08/31/2021] [Indexed: 02/07/2023] Open
Abstract
The melanocortin-4 receptor (MC4R), a hypothalamic master regulator of energy homeostasis and appetite, is a class A G-protein-coupled receptor and a prime target for the pharmacological treatment of obesity. Here, we present cryo-electron microscopy structures of MC4R–Gs-protein complexes with two drugs recently approved by the FDA, the peptide agonists NDP-α-MSH and setmelanotide, with 2.9 Å and 2.6 Å resolution. Together with signaling data from structure-derived MC4R mutants, the complex structures reveal the agonist-induced origin of transmembrane helix (TM) 6-regulated receptor activation. The ligand-binding modes of NDP-α-MSH, a high-affinity linear variant of the endogenous agonist α-MSH, and setmelanotide, a cyclic anti-obesity drug with biased signaling toward Gq/11, underline the key role of TM3 in ligand-specific interactions and of calcium ion as a ligand-adaptable cofactor. The agonist-specific TM3 interplay subsequently impacts receptor–Gs-protein interfaces at intracellular loop 2, which also regulates the G-protein coupling profile of this promiscuous receptor. Finally, our structures reveal mechanistic details of MC4R activation/inhibition, and provide important insights into the regulation of the receptor signaling profile which will facilitate the development of tailored anti-obesity drugs.
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26
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Cano G, Hernan SL, Sved AF. Centrally Projecting Edinger-Westphal Nucleus in the Control of Sympathetic Outflow and Energy Homeostasis. Brain Sci 2021; 11:1005. [PMID: 34439626 PMCID: PMC8392615 DOI: 10.3390/brainsci11081005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 07/13/2021] [Accepted: 07/20/2021] [Indexed: 11/16/2022] Open
Abstract
The centrally projecting Edinger-Westphal nucleus (EWcp) is a midbrain neuronal group, adjacent but segregated from the preganglionic Edinger-Westphal nucleus that projects to the ciliary ganglion. The EWcp plays a crucial role in stress responses and in maintaining energy homeostasis under conditions that require an adjustment of energy expenditure, by virtue of modulating heart rate and blood pressure, thermogenesis, food intake, and fat and glucose metabolism. This modulation is ultimately mediated by changes in the sympathetic outflow to several effector organs, including the adrenal gland, heart, kidneys, brown and white adipose tissues and pancreas, in response to environmental conditions and the animal's energy state, providing for appropriate energy utilization. Classic neuroanatomical studies have shown that the EWcp receives inputs from forebrain regions involved in these functions and projects to presympathetic neuronal populations in the brainstem. Transneuronal tracing with pseudorabies virus has demonstrated that the EWcp is connected polysynaptically with central circuits that provide sympathetic innervation to all these effector organs that are critical for stress responses and energy homeostasis. We propose that EWcp integrates multimodal signals (stress, thermal, metabolic, endocrine, etc.) and modulates the sympathetic output simultaneously to multiple effector organs to maintain energy homeostasis under different conditions that require adjustments of energy demands.
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Affiliation(s)
- Georgina Cano
- Department of Neuroscience, A210 Langley Hall, University of Pittsburgh, Pittsburgh, PA 15260, USA; (S.L.H.); (A.F.S.)
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27
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Lonati C, Battistin M, Dondossola DE, Bassani GA, Brambilla D, Merighi R, Leonardi P, Carlin A, Meroni M, Zanella A, Catania A, Gatti S. NDP-MSH treatment recovers marginal lungs during ex vivo lung perfusion (EVLP). Peptides 2021; 141:170552. [PMID: 33865932 DOI: 10.1016/j.peptides.2021.170552] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 04/02/2021] [Accepted: 04/08/2021] [Indexed: 12/26/2022]
Abstract
The increasing use of marginal lungs for transplantation encourages novel approaches to improve graft quality. Melanocortins and their receptors (MCRs) exert multiple beneficial effects in pulmonary inflammation. We tested the idea that treatment with the synthetic α-melanocyte-stimulating hormone analogue [Nle4,D-Phe7]-α-MSH (NDP-MSH) during ex vivo lung perfusion (EVLP) could exert positive influences in lungs exposed to different injuries. Rats were assigned to one of the following protocols (N = 10 each): 1) ischemia/reperfusion (IR) or 2) cardiac death (CD) followed by ex vivo perfusion. NDP-MSH treatment was performed in five rats of each protocol before lung procurement and during EVLP. Pulmonary function and perfusate concentration of gases, electrolytes, metabolites, nitric-oxide, mediators, and cells were assessed throughout EVLP. ATP content and specific MCR expression were investigated in perfused lungs and in biopsies collected from rats in resting conditions (Native, N = 5). NDP-MSH reduced the release of inflammatory mediators in perfusates of both the IR and the CD groups. Treatment was likewise associated with a lesser amount of leukocytes (IR: p = 0.034; CD: p = 0.002) and reduced lactate production (IR: p = 0.010; CD: p = 0.008). In lungs exposed to IR injury, the NDP-MSH group showed increased ATP content (p = 0.040) compared to controls. In CD lungs, a significant improvement of vascular (p = 0.002) and airway (Ppeak: p < 0.001, compliance: p < 0.050, pO2: p < 0.001) parameters was observed. Finally, the expression of MC1R and MC5R was detected in both native and ex vivo-perfused lungs. The results indicate that NDP-MSH administration preserves lung function through broad positive effects on multiple pathways and suggest that exploitation of the melanocortin system during EVLP could improve reconditioning of marginal lungs before transplantation.
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Affiliation(s)
- Caterina Lonati
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy.
| | - Michele Battistin
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy; Thoracic Surgery and Lung Transplantation Unit, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico of Milan, via Francesco Sforza 35, 20100, Italy
| | - Daniele E Dondossola
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy; General and Liver Transplant Surgery Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Francesco Sforza 35, 20100, Milan, Italy; Department of Pathophysiology and Transplantation, University of Milan, via Francesco Sforza 35, 20100, Milan, Italy
| | - Giulia A Bassani
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy
| | - Daniela Brambilla
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy
| | - Riccardo Merighi
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy
| | - Patrizia Leonardi
- Department of Pathophysiology and Transplantation, University of Milan, via Francesco Sforza 35, 20100, Milan, Italy
| | - Andrea Carlin
- Department of Pathophysiology and Transplantation, University of Milan, via Francesco Sforza 35, 20100, Milan, Italy
| | - Marica Meroni
- General Medicine and Metabolic Diseases, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Francesco Sforza 35, Milan, 20122, Italy
| | - Alberto Zanella
- Department of Pathophysiology and Transplantation, University of Milan, via Francesco Sforza 35, 20100, Milan, Italy; Department of Anesthesia and Critical Care, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Francesco Sforza 35, 20100, Milan, Italy
| | - Anna Catania
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy; Emeritus, Italy
| | - Stefano Gatti
- Center for Preclinical Research, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, via Pace 9, 20100, Milan, Italy
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28
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Durek T, Kaas Q, White AM, Weidmann J, Fuaad AA, Cheneval O, Schroeder CI, de Veer SJ, Dellsén A, Österlund T, Larsson N, Knerr L, Bauer U, Plowright AT, Craik DJ. Melanocortin 1 Receptor Agonists Based on a Bivalent, Bicyclic Peptide Framework. J Med Chem 2021; 64:9906-9915. [PMID: 34197114 DOI: 10.1021/acs.jmedchem.1c00095] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have designed a new class of highly potent bivalent melanocortin receptor ligands based on the nature-derived bicyclic peptide sunflower trypsin inhibitor 1 (SFTI-1). Incorporation of melanotropin pharmacophores in each of the two turn regions of SFTI-1 resulted in substantial gains in agonist activity particularly at human melanocortin receptors 1 and 3 (hMC1R/hMC3R) compared to monovalent analogues. In in vitro binding and functional assays, the most potent molecule, compound 6, displayed low picomolar agonist activity at hMC1R (pEC50 > 10.3; EC50 < 50 pM; pKi: 10.16 ± 0.04; Ki: 69 ± 5 pM) and is at least 30-fold more selective for this receptor than for hMC3R, hMC4R, or hMC5R. The results are discussed in the context of structural homology models of hMCRs in complex with the developed bivalent ligands.
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Affiliation(s)
- Thomas Durek
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Quentin Kaas
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Andrew M White
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Joachim Weidmann
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Abdullah Ahmad Fuaad
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Olivier Cheneval
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Christina I Schroeder
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Simon J de Veer
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Anita Dellsén
- Mechanistic Biology & Profiling, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden
| | - Torben Österlund
- Discovery Biology, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden.,Drug Safety and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden
| | - Niklas Larsson
- Discovery Biology, Discovery Sciences, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden
| | - Laurent Knerr
- Medicinal Chemistry, Cardiovascular and Metabolic Diseases, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden
| | - Udo Bauer
- Medicinal Chemistry, Cardiovascular and Metabolic Diseases, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden
| | - Alleyn T Plowright
- Medicinal Chemistry, Cardiovascular and Metabolic Diseases, IMED Biotech Unit, AstraZeneca, Gothenburg 43183, Mölndal, Sweden
| | - David J Craik
- Institute for Molecular Bioscience, Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Queensland, Brisbane, QLD 4072, Australia
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29
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Macedo GG, Batista EDOS, dos Santos GMG, D’Occhio MJ, Baruselli PS. Estradiol Priming Potentiates the Kisspeptin-Induced Release of LH in Ovariectomized Cows. Animals (Basel) 2021; 11:1236. [PMID: 33922956 PMCID: PMC8145406 DOI: 10.3390/ani11051236] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/19/2021] [Accepted: 04/22/2021] [Indexed: 12/25/2022] Open
Abstract
The present study examined whether priming with estradiol benzoate (EB) for 12 h increased both the peak and duration of LH release in response to kisspeptin (KISS1, KP) in cows. In a Latin square design, ovariectomized Nelore cows (n = 8) received: Control, i.m. 4 mL of 0.9% saline; KP, i.m. 4 mg murine KISS1-10; EBKP, i.m. 4 mg KISS1-10 + i.m. 2 mg EB simultaneously; EB12KP, i.m. 4 mg KISS1-10 + i.m. 2 mg EB 12 h before KISS1-10. Concentrations of LH were determined in blood samples obtained at time 0 (treatment), 20, 40, 60, 90, 120, 150, 180, 210 and 270 min. Concentrations of LH were analyzed by Proc GLIMMIX for repeated measures. In case of significance, the adjusted Tukey test was used to test for differences among treatments. GraphPad 8.0 PRISM® was used to determine the area under the LH-response curve (AUC) after injection of KISS1-10. Plasma LH remained relatively constant throughout sampling after treatment with saline. The peak in LH after injection of KISS1-10 occurred at 20 min in Groups KP and EBKP and at 40 min in Group EB12KP. The peak LH response (∆LH, ng/mL) was greater (p < 0.01) in Group EB12KP (5.6 ± 0.9) than in Groups KP (2.4 ± 0.9) and EBKP (3.5 ± 0.9), which did not differ. AUC (LH ng/mL*min) was greater (p = 0.02) in Group EB12KP (439 ± 73) than in Groups KP (176 ± 73) and EBKP (241 ± 73), with the latter two groups not differing. The findings indicated that 12 h priming with EB increased both the peak and duration of the LH response to treatment with KISS1. The incorporation of EB priming and KISS1 could improve the efficiency of estrus synchronization with fixed-time AI in cows. This would have an important practical application in assisted breeding in beef and dairy cattle.
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Affiliation(s)
- Gustavo Guerino Macedo
- Faculty of Veterinary Medicine and Animal Sciences, Federal University of Mato Grosso do Sul, Campo Grande 79070-900, Mato Grosso do Sul, Brazil
| | | | | | - Michael J. D’Occhio
- Faculty of Science, School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia;
| | - Pietro Sampaio Baruselli
- Faculty of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo 05508-270, Sao Paulo, Brazil;
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30
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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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31
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Sharfman N, Gilpin NW. The Role of Melanocortin Plasticity in Pain-Related Outcomes After Alcohol Exposure. Front Psychiatry 2021; 12:764720. [PMID: 34803772 PMCID: PMC8599269 DOI: 10.3389/fpsyt.2021.764720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 10/05/2021] [Indexed: 11/13/2022] Open
Abstract
The global COVID-19 pandemic has shone a light on the rates and dangers of alcohol misuse in adults and adolescents in the US and globally. Alcohol exposure during adolescence causes persistent molecular, cellular, and behavioral changes that increase the risk of alcohol use disorder (AUD) into adulthood. It is established that alcohol abuse in adulthood increases the likelihood of pain hypersensitivity and the genesis of chronic pain, and humans report drinking alcohol to relieve pain symptoms. However, the longitudinal effects of alcohol exposure on pain and the underlying CNS signaling that mediates it are understudied. Specific brain regions mediate pain effects, alcohol effects, and pain-alcohol interactions, and neural signaling in those brain regions is modulated by neuropeptides. The CNS melanocortin system is sensitive to alcohol and modulates pain sensitivity, but this system is understudied in the context of pain-alcohol interactions. In this review, we focus on the role of melanocortin signaling in brain regions sensitive to alcohol and pain, in particular the amygdala. We also discuss interactions of melanocortins with other peptide systems, including the opioid system, as potential mediators of pain-alcohol interactions. Therapeutic strategies that target the melanocortin system may mitigate the negative consequences of alcohol misuse during adolescence and/or adulthood, including effects on pain-related outcomes.
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Affiliation(s)
- Nathan Sharfman
- Department of Physiology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, United States
| | - Nicholas W Gilpin
- Department of Physiology, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, United States.,Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA, United States.,Alcohol and Drug Abuse Center of Excellence, School of Medicine, Louisiana State University Health Sciences Center, New Orleans, LA, United States.,Southeast Louisiana VA Healthcare System (SLVHCS), New Orleans, LA, United States
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32
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Martin C, Gimenez LE, Williams SY, Jing Y, Wu Y, Hollanders C, Van der Poorten O, Gonzalez S, Van Holsbeeck K, Previti S, Lamouroux A, Zhao S, Tourwé D, Stevens RC, Cone RD, Ballet S. Structure-Based Design of Melanocortin 4 Receptor Ligands Based on the SHU-9119-hMC4R Cocrystal Structure†. J Med Chem 2020; 64:357-369. [PMID: 33190475 DOI: 10.1021/acs.jmedchem.0c01620] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The melanocortin receptors (MC1R-MC5R) belong to class A G-protein-coupled receptors (GPCRs) and are known to have receptor-specific roles in normal and diseased states. Selectivity for MC4R is of particular interest due to its involvement in various metabolic disorders, including obesity, feeding regulation, and sexual dysfunctions. To further improve the potency and selectivity of MC4R (ant)agonist peptide ligands, we designed and synthesized a series of cyclic peptides based on the recent crystal structure of MC4R in complex with the well-characterized antagonist SHU-9119 (Ac-Nle4-c[Asp5-His6-DNal(2')7-Arg8-Trp9-Lys10]-NH2). These analogues were pharmacologically characterized in vitro, giving key insights into exploiting binding site subpockets to deliver more selective ligands. More specifically, the side chains of the Nle4, DNal(2')7, and Trp9 residues in SHU-9119, as well as the amide linkage between the Asp5 and Lys10 side chains, were found to represent structural features engaging a hMC4R/hMC3R selectivity switch.
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Affiliation(s)
- Charlotte Martin
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Luis E Gimenez
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Savannah Y Williams
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Yu Jing
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Yiran Wu
- 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, B-1050 Brussels, Belgium
| | - Olivier Van der Poorten
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Simon Gonzalez
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Kevin Van Holsbeeck
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Santo Previti
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Arthur Lamouroux
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Suwen Zhao
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China
| | - Dirk Tourwé
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Raymond C Stevens
- iHuman Institute, ShanghaiTech University, Ren Building, 393 Middle Huaxia Road, Pudong, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, 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, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Steven Ballet
- Research Group of Organic Chemistry, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
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33
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Structural Complexity and Plasticity of Signaling Regulation at the Melanocortin-4 Receptor. Int J Mol Sci 2020; 21:ijms21165728. [PMID: 32785054 PMCID: PMC7460885 DOI: 10.3390/ijms21165728] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 08/03/2020] [Accepted: 08/06/2020] [Indexed: 02/06/2023] Open
Abstract
The melanocortin-4 receptor (MC4R) is a class A G protein-coupled receptor (GPCR), essential for regulation of appetite and metabolism. Pathogenic inactivating MC4R mutations are the most frequent cause of monogenic obesity, a growing medical and socioeconomic problem worldwide. The MC4R mediates either ligand-independent or ligand-dependent signaling. Agonists such as α-melanocyte-stimulating hormone (α-MSH) induce anorexigenic effects, in contrast to the endogenous inverse agonist agouti-related peptide (AgRP), which causes orexigenic effects by suppressing high basal signaling activity. Agonist action triggers the binding of different subtypes of G proteins and arrestins, leading to concomitant induction of diverse intracellular signaling cascades. An increasing number of experimental studies have unraveled molecular properties and mechanisms of MC4R signal transduction related to physiological and pathophysiological aspects. In addition, the MC4R crystal structure was recently determined at 2.75 Å resolution in an inactive state bound with a peptide antagonist. Underpinned by structural homology models of MC4R complexes simulating a presumably active-state conformation compared to the structure of the inactive state, we here briefly summarize the current understanding and key players involved in the MC4R switching process between different activity states. Finally, these perspectives highlight the complexity and plasticity in MC4R signaling regulation and identify gaps in our current knowledge.
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34
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Adrenocorticotropic hormone: an effective "natural" biologic therapy for acute gout? Rheumatol Int 2020; 40:1941-1947. [PMID: 32715340 DOI: 10.1007/s00296-020-04659-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 07/20/2020] [Indexed: 12/16/2022]
Abstract
Treatment of acute gout consists of non-steroidal anti-inflammatory drugs (NSAIDs), colchicine and steroids. However, the typical patient with gout has multiple comorbidities such as cardiovascular disease, hypertension, renal dysfunction or diabetes/metabolic syndrome that represent contraindications to these therapeutic options. The aim of this study is to review the available evidence regarding the use of ACTH as an alternative therapeutic option for acute gout and explore potential mechanisms of action. We performed an electronic search (MEDLINE, Scopus and Web of Science) using the keywords ACTH or adrenocorticotropic hormone combined with gout or crystal-induced arthritis. ACTH appears suitable for patients with many comorbidities due to its good safety profile. Clinical evidence shows that ACTH is at least as effective as classic agents. The mechanism of action of ACTH in gout is not entirely known. Robust experimental evidence points to the direction that ACTH does not act solely by triggering the release of endogenous steroids but also appears to downregulate inflammatory responses by activating melanocortin receptors on innate immune cells, such as macrophages. Moreover, indirect evidence indicates that ACTH may have an IL-1 antagonistic effect. We propose that ACTH may be an alternative therapeutic option for gout in patients with multiple comorbidities. Large-scale studies assessing the efficacy and safety of ACTH compared to classic therapeutic options are needed.
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35
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A compendium of G-protein-coupled receptors and cyclic nucleotide regulation of adipose tissue metabolism and energy expenditure. Clin Sci (Lond) 2020; 134:473-512. [PMID: 32149342 DOI: 10.1042/cs20190579] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/17/2020] [Accepted: 02/24/2020] [Indexed: 12/15/2022]
Abstract
With the ever-increasing burden of obesity and Type 2 diabetes, it is generally acknowledged that there remains a need for developing new therapeutics. One potential mechanism to combat obesity is to raise energy expenditure via increasing the amount of uncoupled respiration from the mitochondria-rich brown and beige adipocytes. With the recent appreciation of thermogenic adipocytes in humans, much effort is being made to elucidate the signaling pathways that regulate the browning of adipose tissue. In this review, we focus on the ligand-receptor signaling pathways that influence the cyclic nucleotides, cAMP and cGMP, in adipocytes. We chose to focus on G-protein-coupled receptor (GPCR), guanylyl cyclase and phosphodiesterase regulation of adipocytes because they are the targets of a large proportion of all currently available therapeutics. Furthermore, there is a large overlap in their signaling pathways, as signaling events that raise cAMP or cGMP generally increase adipocyte lipolysis and cause changes that are commonly referred to as browning: increasing mitochondrial biogenesis, uncoupling protein 1 (UCP1) expression and respiration.
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36
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Yu J, Gimenez LE, Hernandez CC, Wu Y, Wein AH, Han GW, McClary K, Mittal SR, Burdsall K, Stauch B, Wu L, Stevens SN, Peisley A, Williams SY, Chen V, Millhauser GL, Zhao S, Cone RD, Stevens RC. Determination of the melanocortin-4 receptor structure identifies Ca 2+ as a cofactor for ligand binding. Science 2020; 368:428-433. [PMID: 32327598 DOI: 10.1126/science.aaz8995] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 03/09/2020] [Indexed: 12/27/2022]
Abstract
The melanocortin-4 receptor (MC4R) is involved in energy homeostasis and is an important drug target for syndromic obesity. We report the structure of the antagonist SHU9119-bound human MC4R at 2.8-angstrom resolution. Ca2+ is identified as a cofactor that is complexed with residues from both the receptor and peptide ligand. Extracellular Ca2+ increases the affinity and potency of the endogenous agonist α-melanocyte-stimulating hormone at the MC4R by 37- and 600-fold, respectively. The ability of the MC4R crystallized construct to couple to ion channel Kir7.1, while lacking cyclic adenosine monophosphate stimulation, highlights a heterotrimeric GTP-binding protein (G protein)-independent mechanism for this signaling modality. MC4R is revealed as a structurally divergent G protein-coupled receptor (GPCR), with more similarity to lipidic GPCRs than to the homologous peptidic GPCRs.
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Affiliation(s)
- Jing Yu
- iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.,CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Luis E Gimenez
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ciria C Hernandez
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | - Yiran Wu
- iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China
| | - Ariel H Wein
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Gye Won Han
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Kyle McClary
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Sanraj R Mittal
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Kylie Burdsall
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Benjamin Stauch
- Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Lijie Wu
- iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China
| | - Sophia N Stevens
- iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China
| | - Alys Peisley
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA
| | | | - Valerie Chen
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Glenn L Millhauser
- Department of Chemistry and Biochemistry, University of California Santa Cruz, Santa Cruz, CA 95064, USA
| | - Suwen Zhao
- iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Roger D Cone
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA. .,Department of Molecular and Integrative Physiology, School of Medicine, University of Michigan, Ann Arbor, MI 48109, USA
| | - Raymond C Stevens
- iHuman Institute, ShanghaiTech University, Pudong, Shanghai 201210, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.,Departments of Biological Sciences and Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
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37
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Koerperich ZM, Ericson MD, Freeman KT, Speth RC, Pogozheva ID, Mosberg HI, Haskell-Luevano C. Incorporation of Agouti-Related Protein (AgRP) Human Single Nucleotide Polymorphisms (SNPs) in the AgRP-Derived Macrocyclic Scaffold c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-dPro] Decreases Melanocortin-4 Receptor Antagonist Potency and Results in the Discovery of Melanocortin-5 Receptor Antagonists. J Med Chem 2020; 63:2194-2208. [PMID: 31845801 DOI: 10.1021/acs.jmedchem.9b00860] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
While the melanocortin receptors (MCRs) are known to be involved in numerous biological pathways, the potential roles of the MC5R have not been clearly elucidated in humans. Agouti-related protein (AgRP), an MC3R/MC4R antagonist and MC4R inverse agonist, contains an exposed β-hairpin loop composed of six residues (Arg-Phe-Phe-Asn-Ala-Phe) that is imperative for binding and function. Within this active loop of AgRP, four human missense polymorphisms were deposited into the NIH Variation Viewer database. These polymorphisms, Arg111Cys, Arg111His, Phe112Tyr, and Ala115Val (AgRP full-length numbering), were incorporated into the peptide macrocycles c[Pro1-Arg2-Phe3-Phe4-Xaa5-Ala6-Phe7-dPro8], where Xaa was Dap5 or Asn5, to explore the functional effects of these naturally occurring substitutions in a simplified AgRP scaffold. All peptides lowered potency at least 10-fold in a cAMP accumulation assay compared to the parent sequences at the MC4Rs. Compounds MDE 6-82-3c, ZMK 2-82, MDE 6-82-1c, ZMK 2-85, and ZMK 2-112 are also the first AgRP-based chemotypes that antagonize the MC5R.
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Affiliation(s)
- Zoe M Koerperich
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Mark D Ericson
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katie T Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Robert C Speth
- College of Pharmacy, Nova Southeastern University, Fort Lauderdale, Florida 33328-2018, United States.,College of Medicine, Georgetown University, Washington, D.C. 20057, United States
| | - Irina D Pogozheva
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Henry I Mosberg
- Department of Medicinal Chemistry, University of Michigan, Ann Arbor, Michigan 48109, 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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38
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Lonati C, Gatti S, Catania A. Activation of Melanocortin Receptors as a Potential Strategy to Reduce Local and Systemic Reactions Induced by Respiratory Viruses. Front Endocrinol (Lausanne) 2020; 11:569241. [PMID: 33362713 PMCID: PMC7758465 DOI: 10.3389/fendo.2020.569241] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 11/10/2020] [Indexed: 12/17/2022] Open
Abstract
The clinical hallmarks of infections caused by critical respiratory viruses consist of pneumonia, which can progress to acute lung injury (ALI), and systemic manifestations including hypercoagulopathy, vascular dysfunction, and endotheliitis. The disease outcome largely depends on the immune response produced by the host. The bio-molecular mechanisms underlying certain dire consequences of the infection partly arise from an aberrant production of inflammatory molecules, an event denoted as "cytokine storm". Therefore, in addition to antiviral therapies, molecules able to prevent the injury caused by cytokine excess are under investigation. In this perspective, taking advantage of melanocortin peptides and their receptors, components of an endogenous modulatory system that exerts marked anti-inflammatory and immunomodulatory influences, could be an effective therapeutic strategy to control disease evolution. Exploiting the melanocortin system using natural or synthetic ligands can form a realistic basis to counteract certain deleterious effects of respiratory virus infections. The central and peripheral protective actions exerted following melanocortin receptor activation could allow dampening the harmful events that trigger the cytokine storm and endothelial dysfunction while sustaining the beneficial signals required to elicit repair mechanisms. The long standing evidence for melanocortin safety encourages this approach.
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39
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Link R, Veiksina S, Tahk MJ, Laasfeld T, Paiste P, Kopanchuk S, Rinken A. The constitutive activity of melanocortin-4 receptors in cAMP pathway is allosterically modulated by zinc and copper ions. J Neurochem 2019; 153:346-361. [PMID: 31792980 DOI: 10.1111/jnc.14933] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 11/06/2019] [Accepted: 11/29/2019] [Indexed: 01/25/2023]
Abstract
Melanocortin-4 receptors (MC4 R) are unique among G-protein-coupled receptors (GPCRs) as they have endogenous ligands that can exhibit inverse agonistic properties in the case of elevated basal activity. It is known that the constitutive activity of GPCRs strongly affects the ligand-dependent physiological responses, but little is known about these regulatory mechanisms. Since several metal ions have been shown to be important modulators of the signal transduction of GPCRs, we hypothesized that metal ions regulate the basal activity of MC4 Rs. Implementation of a fluorescence anisotropy assay and novel redshifted fluorescent peptides enabled kinetic characterization of ligand binding to MC4 R expressed on budded baculoviruses. We show that Ca2+ is required for high-affinity ligand binding, but Zn2+ and Cu2+ in the presence of Ca2+ behave as negative allosteric modulators of ligand binding to MC4 R. FRET-based cAMP biosensor was used to measure the activation of MC4 R stably expressed in CHO-K1 cells. At low micromolar concentrations, Zn2+ caused MC4 R-dependent activation of the cAMP pathway, whereas Cu2+ reduced the activity of MC4 R even below the basal level. These findings indicate that at physiologically relevant concentrations can Zn2+ and Cu2+ function as MC4 R agonists or inverse agonists, respectively. This means that depending on the level of constitutive activity induced by Zn2+ ions, the pharmacological effect of orthosteric ligands of MC4 R can be switched from a partial to an inverse agonist. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. More information about the Open Science badges can be found at https://cos.io/our-services/open-science-badges/.
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Affiliation(s)
- Reet Link
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | - Santa Veiksina
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | | | - Tõnis Laasfeld
- Institute of Chemistry, University of Tartu, Tartu, Estonia
| | - Päärn Paiste
- Department of Geology, University of Tartu, Tartu, Estonia
| | | | - Ago Rinken
- Institute of Chemistry, University of Tartu, Tartu, Estonia
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40
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Sharma S, Garfield AS, Shah B, Kleyn P, Ichetovkin I, Moeller IH, Mowrey WR, Van der Ploeg LHT. Current Mechanistic and Pharmacodynamic Understanding of Melanocortin-4 Receptor Activation. Molecules 2019; 24:molecules24101892. [PMID: 31100979 PMCID: PMC6572030 DOI: 10.3390/molecules24101892] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 05/15/2019] [Accepted: 05/15/2019] [Indexed: 12/20/2022] Open
Abstract
In this work we summarize our understanding of melanocortin 4 receptor (MC4R) pathway activation, aiming to define a safe and effective therapeutic targeting strategy for the MC4R. Delineation of cellular MC4R pathways has provided evidence for distinct MC4R signaling events characterized by unique receptor activation kinetics. While these studies remain narrow in scope, and have largely been explored with peptidic agonists, the results provide a possible correlation between distinct ligand groups and differential MC4R activation kinetics. In addition, when a set of small-molecule and peptide MC4R agonists are compared, evidence of biased signaling has been reported. The results of such mechanistic studies are discussed.
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Affiliation(s)
| | | | - Bhavik Shah
- Rhythm Pharmaceuticals, Boston, MA 02116, USA.
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41
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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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42
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Spana C, Taylor AW, Yee DG, Makhlina M, Yang W, Dodd J. Probing the Role of Melanocortin Type 1 Receptor Agonists in Diverse Immunological Diseases. Front Pharmacol 2019; 9:1535. [PMID: 30692924 PMCID: PMC6339910 DOI: 10.3389/fphar.2018.01535] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 12/17/2018] [Indexed: 12/12/2022] Open
Abstract
Background: The melanocortin α-melanocyte stimulating hormone (α-MSH), an endogenous peptide with high affinity for the melanocortin 1 receptor (MC1r), has demonstrated prevention and reversal of intestinal and ocular inflammation in animal models. Preclinical studies were performed to determine whether two MC1r receptor agonists, PL-8177 and PL-8331, exhibit actions and efficacy similar to α-MSH in preventing and reversing intestinal and ocular inflammation. Methods: Both PL-8177 and PL-8331 were assessed in a Eurofins LeadProfilingScreen selectivity panel including 72 in vitro assays. PL-8177 and PL-8331 were evaluated in an in vitro assay using human whole blood stimulated by lipopolysaccharide to determine inhibition of tumor necrosis factor alpha (TNF-α); for comparison, adrenocorticotropic hormone (ACTH) and α-MSH were used as positive controls. PL-8177, dosed at 0.5, 1.5, and 5.0 μg, was assessed in a cannulated rat model of dinitrobenzene sulfonic acid (DNBS)-induced bowel inflammation versus vehicle and oral sulfasalazine. PL-8177 was also dosed at 0.3 mg/kg/mouse injected intraperitoneally versus untreated controls and α-MSH treatment in mice with experimental autoimmune uveitis (EAU). PL-8331 at 3 doses, 3 times daily, was evaluated in a murine model of scopolamine-induced dry eye disease (SiccaSystemTM model), versus twice-daily Restasis® and Xiidra®. Results: Both PL-8177 and PL-8331 demonstrated no significant activity at the 1 μm concentration in any of the 72 in vitro assays. PL-8177 and PL-8331 inhibited lipopolysaccharide-induced TNF-α to a similar degree as ACTH and α-MSH. In the DNBS rat model of bowel inflammation, PL-8177 was significantly superior to untreated controls at all 3 doses (P < 0.05) in reducing bowel inflammation parameters, with effects similar to sulfasalazine. In the murine EAU model, PL-8177 significantly reduced retinal inflammation scores versus untreated controls (P = 0.0001) over 3–5 weeks, and to a similar degree as α-MSH. In the murine scopolamine-induced model of dry eye disease, PL-8331 reduced corneal fluorescein staining scores at all doses, significantly (P = 0.02) for the highest dose (1 × 10-5 mg⋅mL-1), and similarly to Restasis®; Xiidra® demonstrated no effect. Conclusion: The MC1r receptor agonists PL-8177 and PL-8331 exhibited actions similar to those of α-MSH in preventing and reversing intestinal and ocular inflammation in preclinical disease models.
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Affiliation(s)
- Carl Spana
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | - Andrew W Taylor
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, United States
| | - David G Yee
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, United States
| | | | - Wei Yang
- Palatin Technologies, Inc., Cranbury, NJ, United States
| | - John Dodd
- Palatin Technologies, Inc., Cranbury, NJ, United States
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43
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Heyder N, Kleinau G, Szczepek M, Kwiatkowski D, Speck D, Soletto L, Cerdá-Reverter JM, Krude H, Kühnen P, Biebermann H, Scheerer P. Signal Transduction and Pathogenic Modifications at the Melanocortin-4 Receptor: A Structural Perspective. Front Endocrinol (Lausanne) 2019; 10:515. [PMID: 31417496 PMCID: PMC6685040 DOI: 10.3389/fendo.2019.00515] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/15/2019] [Indexed: 12/19/2022] Open
Abstract
The melanocortin-4 receptor (MC4R) can be endogenously activated by binding of melanocyte-stimulating hormones (MSH), which mediates anorexigenic effects. In contrast, the agouti-related peptide (AgRP) acts as an endogenous inverse agonist and suppresses ligand-independent basal signaling activity (orexigenic effects). Binding of ligands to MC4R leads to the activation of different G-protein subtypes or arrestin and concomitant signaling pathways. This receptor is a key protein in the hypothalamic regulation of food intake and energy expenditure and naturally-occurring inactivating MC4R variants are the most frequent cause of monogenic obesity. In general, obesity is a growing problem on a global scale and is of social, medical, and economic relevance. A significant goal is to develop optimized pharmacological tools targeting MC4R without adverse effects. To date, this has not been achieved because of inter alia non-selective ligands across the five functionally different MCR subtypes (MC1-5R). This motivates further investigation of (i) the three-dimensional MC4R structure, (ii) binding mechanisms of various ligands, and (iii) the molecular transfer process of signal transduction, with the aim of understanding how structural features are linked with functional-physiological aspects. Unfortunately, experimentally elucidated structural information is not yet available for the MC receptors, a group of class A G-protein coupled receptors (GPCRs). We, therefore, generated MC4R homology models and complexes with interacting partners to describe approximate structural properties associated with signaling mechanisms. In addition, molecular insights from pathogenic mutations were incorporated to discriminate more precisely their individual malfunction of the signal transfer mechanism.
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Affiliation(s)
- Nicolas Heyder
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Gunnar Kleinau
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
- *Correspondence: Gunnar Kleinau
| | - Michal Szczepek
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Dennis Kwiatkowski
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - David Speck
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Lucia Soletto
- Departamento de Fisiología de Peces y Biotecnología, Consejo Superior de Investigaciones Científicas, Instituto de Acuicultura Torre de la Sal, Ribera de Cabanes, Spain
| | - José Miguel Cerdá-Reverter
- Departamento de Fisiología de Peces y Biotecnología, Consejo Superior de Investigaciones Científicas, Instituto de Acuicultura Torre de la Sal, Ribera de Cabanes, Spain
| | - Heiko Krude
- Institute of Experimental Pediatric Endocrinology, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Peter Kühnen
- Institute of Experimental Pediatric Endocrinology, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Heike Biebermann
- Institute of Experimental Pediatric Endocrinology, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Patrick Scheerer
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Berlin Institute of Health, Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
- Patrick Scheerer
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44
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Ericson MD, Koerperich ZM, Freeman KT, Fleming KA, Haskell-Luevano C. Arg-Phe-Phe d-Amino Acid Stereochemistry Scan in the Macrocyclic Agouti-Related Protein Antagonist Scaffold c[Pro-Arg-Phe-Phe-Xxx-Ala-Phe-DPro] Results in Unanticipated Melanocortin-1 Receptor Agonist Profiles. ACS Chem Neurosci 2018; 9:3015-3023. [PMID: 29924583 DOI: 10.1021/acschemneuro.8b00218] [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: 12/21/2022] Open
Abstract
The melanocortin-3 and melanocortin-4 receptors (MC3R and MC4R), endogenous agonists derived from the proopiomelanocortin gene transcript, and naturally occurring antagonists agouti and agouti-related protein (AGRP) have been linked to biological pathways associated with energy homeostasis. The active tripeptide sequence of AGRP, Arg111-Phe112-Phe113, is located on a hypothesized β-hairpin loop. Herein, stereochemical modifications of the Arg-Phe-Phe sequence were examined in the octapeptide AGRP-derived macrocyclic scaffold c[Pro-Arg-Phe-Phe-Xxx-Ala-Phe-DPro], where Xxx was Asn or diaminopropionic acid (Dap). Macrocyclic peptides were synthesized with one, two, or three residues of the Arg-Phe-Phe sequence substituted with the corresponding d-isomer(s), generating a 14 compound library. While l-to-d inversions of the Arg-Phe-Phe sequence in a 20-residue AGRP-derived ligand previously resulted in agonist activity at the MC1R, MC3R, MC4R, and MC5R, only the MC1R was consistently stimulated by the macrocyclic ligands in the present study, with varying ligand potencies and efficacies observed at the MC1R. A general trend of increased MC4R antagonist potency was observed for Dap-containing compounds, while MC5R inverse agonist activity was observed for select ligands. It was observed that stereochemical modification of the Arg-Phe-Phe active tripeptide sequence was insufficient to convert melanocortin antagonist into agonists. Overall, these observations are important in the design of melanocortin ligands possessing potent and selective agonist and antagonist activities.
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Affiliation(s)
- Mark D. Ericson
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455 United States
| | - Zoe M. Koerperich
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455 United States
| | - Katie T. Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455 United States
| | - Katlyn A. Fleming
- 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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45
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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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46
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Fleming KA, Freeman KT, Ericson MD, Haskell-Luevano C. Synergistic Multiresidue Substitutions of a Macrocyclic c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-dPro] Agouti-Related Protein (AGRP) Scaffold Yield Potent and >600-Fold MC4R versus MC3R Selective Melanocortin Receptor Antagonists. J Med Chem 2018; 61:7729-7740. [PMID: 30035543 PMCID: PMC6174881 DOI: 10.1021/acs.jmedchem.8b00684] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Antagonist ligands of the melanocortin-3 and -4 receptors (MC3R, MC4R), including agouti-related protein (AGRP), are postulated to be targets for the treatment of diseases of negative energy balance. Previous studies reported the macrocyclic MC3R/MC4R antagonist c[Pro1-Arg2-Phe3-Phe4-Asn5-Ala6-Phe7-dPro8], which is 250-fold less potent at the mouse (m) mMC3R and 3-fold less potent at the mMC4R than AGRP. Previous studies explored the structure-activity relationships around individual positions in this template. Herein, a multiresidue substitution strategy is utilized, combining the lead sequence with hPhe4, Dap5, Arg5, Ser6, and Nle7 substitutions previously reported. Two compounds from this study (16, 20) contain an hPhe4/Ser6/Nle7 substitution pattern, are 3-6-fold more potent than AGRP at the mMC4R and are 600-800-fold selective for the mMC4R over the mMC3R. Another lead compound (21), possessing the hPhe4/Arg5 substitutions, is only 5-fold less potent than AGRP at the mMC3R and is equipotent to AGRP at the mMC4R.
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Affiliation(s)
- Katlyn A. Fleming
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
| | - Mark D. Ericson
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
| | - Carrie Haskell-Luevano
- University of Minnesota, Department of Medicinal Chemistry and Institute for Translation Neuroscience, Minneapolis, Minnesota 55455, United States
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47
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Saleh N, Kleinau G, Heyder N, Clark T, Hildebrand PW, Scheerer P. Binding, Thermodynamics, and Selectivity of a Non-peptide Antagonist to the Melanocortin-4 Receptor. Front Pharmacol 2018; 9:560. [PMID: 29910730 PMCID: PMC5992272 DOI: 10.3389/fphar.2018.00560] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 05/10/2018] [Indexed: 11/22/2022] Open
Abstract
The melanocortin-4 receptor (MC4R) is a potential drug target for treatment of obesity, anxiety, depression, and sexual dysfunction. Crystal structures for MC4R are not yet available, which has hindered successful structure-based drug design. Using microsecond-scale molecular-dynamics simulations, we have investigated selective binding of the non-peptide antagonist MCL0129 to a homology model of human MC4R (hMC4R). This approach revealed that, at the end of a multi-step binding process, MCL0129 spontaneously adopts a binding mode in which it blocks the agonistic-binding site. This binding mode was confirmed in subsequent metadynamics simulations, which gave an affinity for human hMC4R that matches the experimentally determined value. Extending our simulations of MCL0129 binding to hMC1R and hMC3R, we find that receptor subtype selectivity for hMC4R depends on few amino acids located in various structural elements of the receptor. These insights may support rational drug design targeting the melanocortin systems.
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Affiliation(s)
- Noureldin Saleh
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Computational Modelling and Dynamics of Molecular Complexes, Berlin, Germany
| | - Gunnar Kleinau
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Group Protein X-ray Crystallography and Signal Transduction, Berlin, Germany
| | - Nicolas Heyder
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Group Protein X-ray Crystallography and Signal Transduction, Berlin, Germany
| | - Timothy Clark
- Computer-Chemie-Centrum, Department of Chemistry and Pharmacy, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Peter W Hildebrand
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Computational Modelling and Dynamics of Molecular Complexes, Berlin, Germany.,Institute of Medical Physics and Biophysics, Leipzig University, Leipzig, Germany
| | - Patrick Scheerer
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Institute of Medical Physics and Biophysics, Berlin, Germany.,Group Protein X-ray Crystallography and Signal Transduction, Berlin, Germany
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48
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Tala SR, Singh A, Lensing CJ, Schnell SM, Freeman KT, Rocca JR, Haskell-Luevano C. 1,2,3-Triazole Rings as a Disulfide Bond Mimetic in Chimeric AGRP-Melanocortin Peptides: Design, Synthesis, and Functional Characterization. ACS Chem Neurosci 2018; 9:1001-1013. [PMID: 29257879 DOI: 10.1021/acschemneuro.7b00422] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The melanocortin system is involved in the regulation of complex physiological functions, including energy and weight homeostasis, feeding behavior, inflammation, sexual function, pigmentation, and exocrine gland function. The five melanocortin receptors that belong to the superfamily of G protein-coupled receptors (GPCRs) are regulated by endogenously expressed agonists and antagonists. The aim of this study was to explore the potential of replacing the disulfide bridge in chimeric AGRP-melanocortin peptide Tyr-c[Cys-His-d-Phe-Arg-Trp-Asn-Ala-Phe-Cys]-Tyr-NH2 (1) with 1,2,3-triazole moieties. A series of 1,2,3-triazole-bridged peptidomimetics were designed, synthesized, and pharmacologically evaluated at the mouse melanocortin receptors. The ligands possessed nanomolar to micromolar agonist cAMP signaling potency. A key finding was that the disulfide bond in peptide 1 can be replaced with the monotriazole ring with minimal effect on the functional activity at the melanocortin receptors. The 1,5-disubstituted triazole-bridged peptide 6 showed equipotent functional activity at the mMC3R and modest 5-fold decreased agonist potency at the mMC4R compared to those of 1. Interestingly, the 1,4- and 1,5-disubstituted isomers of the triazole ring resulted in different selectivities at the receptor subtypes, indicating subtle structural features that may be exploited in the generation of selective melanocortin ligands. Introducing cyclic and acyclic bis-triazole moieties into chimeric AGRP template 1 generally decreased agonist activity. These results will be useful for the further design of neuronal chemical probes for the melanocortin receptors as well as in other receptor systems.
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Affiliation(s)
- Srinivasa R. Tala
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Anamika Singh
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Cody J. Lensing
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sathya M. Schnell
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - James R. Rocca
- Advanced Magnetic Resonance Imaging and Spectroscopy, McKnight Brain Institute, University of Florida, Gainesville, Florida 32610, United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
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49
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Fleming KA, Ericson MD, Freeman KT, Adank DN, Lunzer MM, Wilber SL, Haskell-Luevano C. Structure-Activity Relationship Studies of a Macrocyclic AGRP-Mimetic Scaffold c[Pro-Arg-Phe-Phe-Asn-Ala-Phe-DPro] Yield Potent and Selective Melanocortin-4 Receptor Antagonists and Melanocortin-5 Receptor Inverse Agonists That Increase Food Intake in Mice. ACS Chem Neurosci 2018; 9:1141-1151. [PMID: 29363944 PMCID: PMC5955836 DOI: 10.1021/acschemneuro.7b00495] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The melanocortin system has five receptors, and antagonists of the central melanocortin receptors (MC3R, MC4R) are postulated to be viable therapeutics for disorders of negative energy balance such as anorexia, cachexia, and failure to thrive. Agouti-related protein (AGRP) is an antagonist of the MC3R and an antagonist/inverse agonist of the MC4R. Biophysical NMR-based structural studies have demonstrated that the active sequence of this hormone, Arg-Phe-Phe, is located on an exposed β-hairpin loop. It has previously been demonstrated that the macrocyclic octapeptide scaffold c[Pro1-Arg2-Phe3-Phe4-Asn5-Ala6-Phe7-DPro8] is 16-fold less potent than AGRP at the mouse MC4R (mMC4R). Herein it was hypothesized that the Phe7 position may be substituted to produce more potent and/or selective melanocortin receptor antagonist ligands based on this template. A 10-membered library was synthesized that substituted small (Gly), polar (Ser), acidic (Asp), basic (Lys), aliphatic (Leu, Nle, and Cha), and aromatic (Trp, Tyr, hPhe) amino acids to explore potential modifications at the Phe7 position. The most potent mMC4R antagonist contained a Nle7 substitution, was equipotent to the lead ligand 200-fold selective for the mMC4R over the mMC3R, and caused a significant increase in food intake when injected intrathecally into male mice. Three compounds possessed sigmoidal dose-response inverse agonist curves at the mMC5R, while the remaining seven decreased cAMP production from basal levels at a concentration of 100 μM. These findings will add to the knowledge base toward the development of potent and selective probes to study the role of the melanocortin system in diseases of negative energy balance and can be useful in the design of molecular probes to examine the physiological functions of the mMC5R.
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Affiliation(s)
- Katlyn A. Fleming
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Mark D. Ericson
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Katie T. Freeman
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Danielle N. Adank
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Mary M. Lunzer
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Stacey L. Wilber
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
| | - Carrie Haskell-Luevano
- University of Minnesota, Department of Medicinal Chemistry, Minneapolis, Minnesota 55455, United States
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50
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Lensing CJ, Freeman KT, Schnell SM, Speth RC, Zarth AT, Haskell-Luevano C. Developing a Biased Unmatched Bivalent Ligand (BUmBL) Design Strategy to Target the GPCR Homodimer Allosteric Signaling (cAMP over β-Arrestin 2 Recruitment) Within the Melanocortin Receptors. J Med Chem 2018; 62:144-158. [PMID: 29669202 DOI: 10.1021/acs.jmedchem.8b00238] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Understanding the functional relevance of G protein-coupled receptor (GPCR) homodimerization has been limited by the insufficient tools to assess asymmetric signaling occurring within dimers comprised of the same receptor type. We present unmatched bivalent ligands (UmBLs) to study the asymmetric function of melanocortin homodimers. UmBLs contain one agonist and one antagonist pharmacophore designed to target a melanocortin homodimer such that one receptor is occupied by an agonist and the other receptor by an antagonist pharmacophore. First-in-class biased UmBLs (BUmBLs) targeting the human melanocortin-4 receptor (hMC4R) were discovered. The BUmBLs displayed biased agonism by potently stimulating cAMP signaling (EC50 ∼ 2-6 nM) but minimally activating the β-arrestin recruitment pathway (≤55% maximum signal at 10 μM). To our knowledge, we report the first single-compound strategy to pharmacologically target melanocortin receptor allosteric signaling that occurs between homodimers that can be applied straightforwardly in vitro and in vivo to other GPCR systems.
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Affiliation(s)
- Cody J Lensing
- Department of Medicinal Chemistry and Institute for Translational Neuroscience , University of Minnesota , 308 Harvard Street SE , Minneapolis , Minnesota 55455 , United States
| | - Katie T Freeman
- Department of Medicinal Chemistry and Institute for Translational Neuroscience , University of Minnesota , 308 Harvard Street SE , Minneapolis , Minnesota 55455 , United States
| | - Sathya M Schnell
- Department of Medicinal Chemistry and Institute for Translational Neuroscience , University of Minnesota , 308 Harvard Street SE , 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
| | - Adam T Zarth
- Department of Medicinal Chemistry and Institute for Translational Neuroscience , University of Minnesota , 308 Harvard Street SE , Minneapolis , Minnesota 55455 , United States.,Masonic Cancer Center , University of Minnesota , 2231 Sixth Street SE, 2-210 CCRB , Minneapolis , Minnesota 55455 , United States
| | - Carrie Haskell-Luevano
- Department of Medicinal Chemistry and Institute for Translational Neuroscience , University of Minnesota , 308 Harvard Street SE , Minneapolis , Minnesota 55455 , United States
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