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D'Aloisio V, Schofield A, Kendall DA, Hutcheon GA, Coxon CR. The development and optimisation of an HPLC-based in vitro serum stability assay for a calcitonin gene-related peptide receptor antagonist peptide. J Pept Sci 2024; 30:e3539. [PMID: 37605343 DOI: 10.1002/psc.3539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/23/2023]
Abstract
Evaluation of the stability of peptide drug candidates in biological fluids, such as blood serum, is of high importance during the lead optimisation phase. Here, we describe the optimisation and validation of a method for the evaluation of the stability of a lead calcitonin gene-related peptide antagonist peptide (P006) in blood serum. After initially determining appropriate peptide and human serum concentrations and selection of the quenching reagent, the HPLC method optimisation used two experimental designs, Plackett-Burman design and Taguchi design. The analytical method was validated as complying with the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. The optimised method allowed the successful resolution of the parent peptide from its metabolites using RP-HPLC and identification of the major metabolites of P006 by mass spectrometry. This paradigm may be widely adopted as a robust early-stage platform for screening peptide stability to rule out candidates with low in vitro stability, which would likely translate into poor in vivo pharmacokinetics.
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Affiliation(s)
- Vera D'Aloisio
- School of Pharmacy and Biomolecular Sciences, Faculty of Science, Liverpool John Moores University, Liverpool, UK
- EaStChem School of Chemistry, The University of Edinburgh, Joseph Black Building, Edinburgh, UK
| | - Adam Schofield
- EaStChem School of Chemistry, The University of Edinburgh, Joseph Black Building, Edinburgh, UK
| | | | - Gillian A Hutcheon
- School of Pharmacy and Biomolecular Sciences, Faculty of Science, Liverpool John Moores University, Liverpool, UK
| | - Christopher R Coxon
- EaStChem School of Chemistry, The University of Edinburgh, Joseph Black Building, Edinburgh, UK
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2
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Killoran PM, Capel V, D'Aloisio V, Schofield A, Aczél T, Bölcskei K, Helyes Z, von Mentzer B, Kendall DA, Coxon CR, Hutcheon GA. Novel peptide calcitonin gene-related peptide antagonists for migraine therapy. J Pharm Pharmacol 2023; 75:1581-1589. [PMID: 37742055 DOI: 10.1093/jpp/rgad081] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 08/22/2023] [Indexed: 09/25/2023]
Abstract
OBJECTIVES It has previously been shown that the peptide (34Pro,35Phe)CGRP27-37 is a potent calcitonin gene-related peptide, CGRP receptor antagonist, and in this project we aimed to improve the antagonist potency through the structural modification of truncated C-terminal CGRP peptides. METHODS Six peptide analogues were synthesized and the anti-CGRP activity confirmed using both in vitro and in vivo studies. KEY FINDINGS A 10 amino acid-containing peptide VPTDVGPFAF-NH2 (P006) was identified as a key candidate to take forward for in vivo evaluation, where it was shown to be an effective antagonist after intraperitoneal injection into mice. P006 was formulated as a preparation suitable for nasal administration by spray drying with chitosan to form mucoadhesive microcarriers (9.55 ± 0.91 mm diameter) and a loading of 0.2 mg peptide per 20 mg dose. CONCLUSIONS The project has demonstrated the potential of these novel small peptide CGRP antagonists, to undergo future preclinical evaluation as anti-migraine therapeutics.
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Affiliation(s)
- Patrick M Killoran
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, L3 3AF, United Kingdom
| | - Vicky Capel
- NHS Health Education England, Victoria House, Fulbourn, Cambridge, CB21 5XB, United Kingdom
| | - Vera D'Aloisio
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, L3 3AF, United Kingdom
- AmbioPharm, Inc., 1024 Dittman Court, North Augusta, SC 29842, United States
| | - Adam Schofield
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David, Brewster Road, Edinburgh, EH14 4AS, United Kingdom
| | - Tímea Aczél
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, Szigeti út 12, Pécs, Hungary
- Eötvös Lorand Research Network, Chronic Pain Research Group, University of Pécs, Szigeti út 12, Pécs, Hungary
| | - Kata Bölcskei
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, Szigeti út 12, Pécs, Hungary
- Eötvös Lorand Research Network, Chronic Pain Research Group, University of Pécs, Szigeti út 12, Pécs, Hungary
| | - Zsuzsanna Helyes
- Department of Pharmacology and Pharmacotherapy, University of Pécs Medical School, Szigeti út 12, Pécs, Hungary
- Eötvös Lorand Research Network, Chronic Pain Research Group, University of Pécs, Szigeti út 12, Pécs, Hungary
- PharmInVivo Ltd., Szondi Gy. u. 10. H-7629, Pécs, Hungary
- National Laboratory for Drug Research and Development, Magyar tudósok krt. 2, H-1117 Budapest, Hungary
| | - Bengt von Mentzer
- Innovipharm Limited, 2 Woodlands Lane, West Kirby, Wirral, CH48 8D, United Kingdom
| | - David A Kendall
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, L3 3AF, United Kingdom
- Innovipharm Limited, 2 Woodlands Lane, West Kirby, Wirral, CH48 8D, United Kingdom
| | - Chris R Coxon
- EaStCHEM School of Chemistry, The University of Edinburgh, Joseph Black Building, David, Brewster Road, Edinburgh, EH14 4AS, United Kingdom
| | - Gillian A Hutcheon
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, L3 3AF, United Kingdom
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Jamaluddin A, Chuang CL, Williams ET, Siow A, Yang SH, Harris PWR, Petersen JSSM, Bower RL, Chand S, Brimble MA, Walker CS, Hay DL, Loomes KM. Lipidated Calcitonin Gene-Related Peptide (CGRP) Peptide Antagonists Retain CGRP Receptor Activity and Attenuate CGRP Action In Vivo. Front Pharmacol 2022; 13:832589. [PMID: 35341216 PMCID: PMC8942775 DOI: 10.3389/fphar.2022.832589] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 02/09/2022] [Indexed: 11/13/2022] Open
Abstract
Signaling through calcitonin gene-related peptide (CGRP) receptors is associated with pain, migraine, and energy expenditure. Small molecule and monoclonal antibody CGRP receptor antagonists that block endogenous CGRP action are in clinical use as anti-migraine therapies. By comparison, the potential utility of peptide antagonists has received less attention due to suboptimal pharmacokinetic properties. Lipidation is an established strategy to increase peptide half-life in vivo. This study aimed to explore the feasibility of developing lipidated CGRP peptide antagonists that retain receptor antagonist activity in vitro and attenuate endogenous CGRP action in vivo. CGRP peptide analogues based on the archetypal CGRP receptor antagonist, CGRP8-37, were palmitoylated at the N-terminus, position 24, and near the C-terminus at position 35. The antagonist activities of the lipidated peptide analogues were tested in vitro using transfected Cos-7 cells expressing either the human or mouse CGRP receptor, amylin subtype 1 (AMY1) receptor, adrenomedullin (AM) receptors, or calcitonin receptor. Antagonist activities were also evaluated in SK-N-MC cells that endogenously express the human CGRP receptor. Lipidated peptides were then tested for their ability to antagonize endogenous CGRP action in vivo using a capsaicin-induced dermal vasodilation (CIDV) model in C57/BL6J mice. All lipidated peptides except for the C-terminally modified analogue retained potent antagonist activity compared to CGRP8-37 towards the CGRP receptor. The lipidated peptides also retained, and sometimes gained, antagonist activities at AMY1, AM1 and AM2 receptors. Several lipidated peptides produced robust inhibition of CIDV in mice. This study demonstrates that selected lipidated peptide antagonists based on αCGRP8-37 retain potent antagonist activity at the CGRP receptor and are capable of inhibition of endogenous CGRP action in vivo. These findings suggest that lipidation can be applied to peptide antagonists, such as αCGRP8-37 and are a potential strategy for antagonizing CGRP action.
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Affiliation(s)
- Aqfan Jamaluddin
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Chia-Lin Chuang
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Elyse T Williams
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Andrew Siow
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Sung Hyun Yang
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | - Paul W R Harris
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | | | - Rebekah L Bower
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Shanan Chand
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Margaret A Brimble
- School of Chemical Sciences, University of Auckland, Auckland, New Zealand
| | | | - Debbie L Hay
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.,Department of Pharmacology and Toxicology, University of Otago, Dunedin, New Zealand
| | - Kerry M Loomes
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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4
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Srinivasan K, Kozminski K, Zhang Y, Wisniewski K, Kohout T, Wisniewska H, Harris G, Lindstrom B, Hargrove D. Pharmacological, Pharmacokinetic, Pharmacodynamic and Physicochemical Characterization of FE 205030: A Potent, Fast Acting, Injectable CGRP Receptor Antagonist for the Treatment of Acute Episodic Migraine. J Pharm Sci 2021; 111:247-261. [PMID: 34217775 DOI: 10.1016/j.xphs.2021.06.034] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/27/2021] [Accepted: 06/29/2021] [Indexed: 12/11/2022]
Abstract
The neuropeptide calcitonin gene-related peptide (CGRP) is known to play a central role in the underlying pathophysiology of migraine. In comparison to the effective triptan class of antimigraine treatments, the CGRP antagonists possess a comparable efficacy but a superior cardiovascular safety profile in patients. This paper describes the development of selective and potent peptidic CGRP antagonist, FE 205030, that has a fast onset of action and an optimal half-life (subcutaneous Tmax ~ 60 min, and t1/2 ~ 4.4 h in 80 kg pigs, respectively), which is key to prevention of the progression of debilitating migraine symptoms. The in vivo efficacy of this agent has been established a translational pharmacodynamic model (inhibition of capsaicin-induced increase in skin blood flow) in cynomolgus monkeys and shows maximal inhibitory activity at circulating concentrations of 30-100 nM. Antagonist activity of FE 205030 was characterized on CGRP-induced vasodilation in isolated human mesenteric resistance arteries in an ex vivo isometric myograph study, and FE 205030 effectively blocked CGRP-induced vasodilation with a pA2 of 9.3 ± 0.1, mean ± standard error. Multispecies allometric scaling and modeling of subcutaneous (SC) effective concentrations indicates that a dose of 10-30 mg/day is sufficient to achieve a drug exposure/target coverage of 8h, which is useful to prevent migraine recurrence in patients. The molecule also possesses appropriate physicochemical properties that allows for a convenient dosing form factor of 1 ml injection volume with a sufficient solubility and acceptable short-term stability, optimal for treatment of acute migraine episodes in patients. Hence, FE 205030 may provide an important fast-acting injectable option for patients suffering from frequent acute migraine episodes, complementary to preventative monoclonal antibodies and oral small molecule CGRP-R antagonist therapies.
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Affiliation(s)
- Karthik Srinivasan
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States.
| | - Kirk Kozminski
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Ying Zhang
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Kazimierz Wisniewski
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Trudy Kohout
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Halina Wisniewska
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Geoffrey Harris
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Beatriz Lindstrom
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
| | - Diane Hargrove
- Ferring Research Institute, Ferring Pharmaceuticals, 4245 Sorrento Valley Blvd, San Diego, CA 92121, United States
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Henninot A, Collins JC, Nuss JM. The Current State of Peptide Drug Discovery: Back to the Future? J Med Chem 2017; 61:1382-1414. [PMID: 28737935 DOI: 10.1021/acs.jmedchem.7b00318] [Citation(s) in RCA: 638] [Impact Index Per Article: 91.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Over the past decade, peptide drug discovery has experienced a revival of interest and scientific momentum, as the pharmaceutical industry has come to appreciate the role that peptide therapeutics can play in addressing unmet medical needs and how this class of compounds can be an excellent complement or even preferable alternative to small molecule and biological therapeutics. In this Perspective, we give a concise description of the recent progress in peptide drug discovery in a holistic manner, highlighting enabling technological advances affecting nearly every aspect of this field: from lead discovery, to synthesis and optimization, to peptide drug delivery. An emphasis is placed on describing research efforts to overcome the inherent weaknesses of peptide drugs, in particular their poor pharmacokinetic properties, and how these efforts have been critical to the discovery, design, and subsequent development of novel therapeutics.
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Affiliation(s)
- Antoine Henninot
- Ferring Research Institute , 4245 Sorrento Valley Boulevard, San Diego, California 92121, United States
| | - James C Collins
- Ferring Research Institute , 4245 Sorrento Valley Boulevard, San Diego, California 92121, United States
| | - John M Nuss
- Ferring Research Institute , 4245 Sorrento Valley Boulevard, San Diego, California 92121, United States
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Mroz PA, Perez-Tilve D, Liu F, Gelfanov V, DiMarchi RD, Mayer JP. Pyridyl-alanine as a Hydrophilic, Aromatic Element in Peptide Structural Optimization. J Med Chem 2016; 59:8061-7. [PMID: 27509198 DOI: 10.1021/acs.jmedchem.6b00840] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Glucagon (Gcg) 1 serves a seminal physiological role in buffering against hypoglycemia, but its poor biophysical properties severely complicate its medicinal use. We report a series of novel glucagon analogues of enhanced aqueous solubility and stability at neutral pH, anchored by Gcg[Aib16]. Incorporation of 3- and 4-pyridyl-alanine (3-Pal and 4-Pal) enhanced aqueous solubility of glucagon while maintaining biological properties. Relative to native hormone, analogue 9 (Gcg[3-Pal6,10,13, Aib16]) demonstrated superior biophysical character, better suitability for medicinal purposes, and comparable pharmacology against insulin-induced hypoglycemia in rats and pigs. Our data indicate that Pal is a versatile surrogate to natural aromatic amino acids and can be employed as an alternative or supplement with isoelectric adjustment to refine the biophysical character of peptide drug candidates.
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Affiliation(s)
- Piotr A Mroz
- Department of Chemistry, Indiana University , 800 East Kirkwood, Bloomington, Indiana 47405 United States
| | - Diego Perez-Tilve
- Department of Medicine, Metabolic Diseases Institute, University of Cincinnati , Cincinnati, Ohio 45267 United States
| | - Fa Liu
- Novo Nordisk Research Center , Indianapolis, Indiana 46241, United States
| | - Vasily Gelfanov
- Novo Nordisk Research Center , Indianapolis, Indiana 46241, United States
| | - Richard D DiMarchi
- Department of Chemistry, Indiana University , 800 East Kirkwood, Bloomington, Indiana 47405 United States.,Novo Nordisk Research Center , Indianapolis, Indiana 46241, United States
| | - John P Mayer
- Novo Nordisk Research Center , Indianapolis, Indiana 46241, United States
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7
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Miranda LP, Shi L, Holder JR, Wright M, Gegg CV, Johnson E, Wild K, Stenkilsson M, Doellgast G, Manning BH, Salyers K. Peptide antagonists of the calcitonin gene-related peptide (CGRP) receptor with improved pharmacokinetics and pharmacodynamics. Biopolymers 2016; 100:422-30. [PMID: 23868210 DOI: 10.1002/bip.22270] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 04/15/2013] [Accepted: 04/19/2013] [Indexed: 11/06/2022]
Abstract
Antagonism of the calcitonin gene-related peptide (CGRP) receptor may be a useful approach for migraine treatment. Selective PEGylated peptide antagonists to the CGRP receptor are described, derived from CGRP(8-37) with polymer derivatization at an engineered lysine-25 residue. Potent PEGylated peptides with improved pharmacokinetics were identified through peptide side-chain modification to mitigate metabolic liabilities. PEGylated Ac-Trp-[Cit(11,18),hArg(24),Lys(25),Asp(31),Pro(34),1-Nal(35)]CGRP(8-37)-NH2, 9, elicits a dose-dependent reduction of intradermal CGRP-induced local blood flow in rodents with an ED50 of 0.52 mg kg(-1) without any overt adverse effects.
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Affiliation(s)
- Les P Miranda
- Therapeutic Discovery, Amgen, Inc., One Amgen Center Drive, Thousand Oaks, CA, 91320
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Russell FA, King R, Smillie SJ, Kodji X, Brain SD. Calcitonin gene-related peptide: physiology and pathophysiology. Physiol Rev 2014; 94:1099-142. [PMID: 25287861 PMCID: PMC4187032 DOI: 10.1152/physrev.00034.2013] [Citation(s) in RCA: 747] [Impact Index Per Article: 74.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Calcitonin gene-related peptide (CGRP) is a 37-amino acid neuropeptide. Discovered 30 years ago, it is produced as a consequence of alternative RNA processing of the calcitonin gene. CGRP has two major forms (α and β). It belongs to a group of peptides that all act on an unusual receptor family. These receptors consist of calcitonin receptor-like receptor (CLR) linked to an essential receptor activity modifying protein (RAMP) that is necessary for full functionality. CGRP is a highly potent vasodilator and, partly as a consequence, possesses protective mechanisms that are important for physiological and pathological conditions involving the cardiovascular system and wound healing. CGRP is primarily released from sensory nerves and thus is implicated in pain pathways. The proven ability of CGRP antagonists to alleviate migraine has been of most interest in terms of drug development, and knowledge to date concerning this potential therapeutic area is discussed. Other areas covered, where there is less information known on CGRP, include arthritis, skin conditions, diabetes, and obesity. It is concluded that CGRP is an important peptide in mammalian biology, but it is too early at present to know if new medicines for disease treatment will emerge from our knowledge concerning this molecule.
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Affiliation(s)
- F A Russell
- Cardiovascular Division, BHF Centre of Research Excellence & Centre of Integrative Biomedicine, King's College London, Waterloo Campus, London SE1 9NH, United Kingdom
| | - R King
- Cardiovascular Division, BHF Centre of Research Excellence & Centre of Integrative Biomedicine, King's College London, Waterloo Campus, London SE1 9NH, United Kingdom
| | - S-J Smillie
- Cardiovascular Division, BHF Centre of Research Excellence & Centre of Integrative Biomedicine, King's College London, Waterloo Campus, London SE1 9NH, United Kingdom
| | - X Kodji
- Cardiovascular Division, BHF Centre of Research Excellence & Centre of Integrative Biomedicine, King's College London, Waterloo Campus, London SE1 9NH, United Kingdom
| | - S D Brain
- Cardiovascular Division, BHF Centre of Research Excellence & Centre of Integrative Biomedicine, King's College London, Waterloo Campus, London SE1 9NH, United Kingdom
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Watkins HA, Au M, Bobby R, Archbold JK, Abdul-Manan N, Moore JM, Middleditch MJ, Williams GM, Brimble MA, Dingley AJ, Hay DL. Identification of key residues involved in adrenomedullin binding to the AM1 receptor. Br J Pharmacol 2014; 169:143-55. [PMID: 23351143 DOI: 10.1111/bph.12118] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 12/11/2012] [Accepted: 01/07/2013] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Adrenomedullin (AM) is a peptide hormone whose receptors are members of the class B GPCR family. They comprise a heteromer between the GPCR, the calcitonin receptor-like receptor and one of the receptor activity-modifying proteins 1-3. AM plays a significant role in angiogenesis and its antagonist fragment AM22-52 can inhibit blood vessel and tumour growth. The mechanism by which AM interacts with its receptors is unknown. EXPERIMENTAL APPROACH We determined the AM22-52 binding epitope for the AM1 receptor extracellular domain using biophysical techniques, heteronuclear magnetic resonance spectroscopy and alanine scanning. KEY RESULTS Chemical shift perturbation experiments located the main binding epitope for AM22-52 at the AM1 receptor to the C-terminal 8 amino acids. Isothermal titration calorimetry of AM22-52 alanine-substituted peptides indicated that Y52, G51 and I47 are essential for AM1 receptor binding and that K46 and P49 and R44 have a smaller role to play. Characterization of these peptides at the full-length AM receptors was assessed in Cos7 cells by cAMP assay. This confirmed the essential role of Y52, G51 and I47 in binding to the AM1 receptor, with their substitution resulting in ≥100-fold reduction in antagonist potency compared with AM22-52 . R44A, K46A, S48A and P49A AM22-52 decreased antagonist potency by approximately 10-fold. CONCLUSIONS AND IMPLICATIONS This study localizes the main binding epitope of AM22-52 to its C-terminal amino acids and distinguishes essential residues involved in this binding. This will inform the development of improved AM receptor antagonists.
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Affiliation(s)
- H A Watkins
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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Watkins HA, Rathbone DL, Barwell J, Hay DL, Poyner DR. Structure-activity relationships for α-calcitonin gene-related peptide. Br J Pharmacol 2013; 170:1308-22. [PMID: 23186257 PMCID: PMC3838678 DOI: 10.1111/bph.12072] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 10/11/2012] [Accepted: 11/15/2012] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED Calcitonin gene-related peptide (CGRP) is a member of the calcitonin (CT) family of peptides. It is a widely distributed neuropeptide implicated in conditions such as neurogenic inflammation. With other members of the CT family, it shares an N-terminal disulphide-bonded ring which is essential for biological activity, an area of potential α-helix, and a C-terminal amide. CGRP binds to the calcitonin receptor-like receptor (CLR) in complex with receptor activity-modifying protein 1 (RAMP1), a member of the family B (or secretin-like) GPCRs. It can also activate other CLR or calcitonin-receptor/RAMP complexes. This 37 amino acid peptide comprises the N-terminal ring that is required for receptor activation (residues 1-7); an α-helix (residues 8-18), a region incorporating a β-bend (residues 19-26) and the C-terminal portion (residues 27-37), that is characterized by bends between residues 28-30 and 33-34. A few residues have been identified that seem to make major contributions to receptor binding and activation, with a larger number contributing either to minor interactions (which collectively may be significant), or to maintaining the conformation of the bound peptide. It is not clear if CGRP follows the pattern of other family B GPCRs in binding largely as an α-helix. LINKED ARTICLES This article is part of a themed section on Neuropeptides. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.170.issue-7.
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Affiliation(s)
- Harriet A Watkins
- School of Biological Sciences, University of AucklandAuckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of AucklandAuckland, New Zealand
| | - Dan L Rathbone
- School of Life and Health Sciences, Aston UniversityBirmingham, UK
| | - James Barwell
- School of Life and Health Sciences, Aston UniversityBirmingham, UK
| | - Debbie L Hay
- School of Biological Sciences, University of AucklandAuckland, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, University of AucklandAuckland, New Zealand
| | - David R Poyner
- School of Life and Health Sciences, Aston UniversityBirmingham, UK
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