1
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Samuel CS, Li Y, Wang Y, Widdop RE. Functional crosstalk between angiotensin receptors (types 1 and 2) and relaxin family peptide receptor 1 (RXFP1): Implications for the therapeutic targeting of fibrosis. Br J Pharmacol 2024; 181:2302-2318. [PMID: 36560925 DOI: 10.1111/bph.16019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 12/15/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
Class A, rhodopsin-like, G-protein-coupled receptors (GPCRs) are by far the largest class of GPCRs and are integral membrane proteins used by various cells to convert extracellular signals into intracellular responses. Initially, class A GPCRs were believed to function as monomers, but a growing body of evidence has emerged to suggest that these receptors can function as homodimers and heterodimers and can undergo functional crosstalk to influence the actions of agonists or antagonists acting at each receptor. This review will focus on the angiotensin type 1 (AT1) and type 2 (AT2) receptors, as well as the relaxin family peptide receptor 1 (RXFP1), each of which have their unique characteristics but have been demonstrated to undergo some level of interaction when appropriately co-expressed, which influences the function of each receptor. In particular, this receptor functional crosstalk will be discussed in the context of fibrosis, the tissue scarring that results from a failed wound-healing response to injury, and which is a hallmark of chronic disease and related organ dysfunction. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein-Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc.
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Affiliation(s)
- Chrishan S Samuel
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute and Department of Pharmacology, Monash University, Clayton, Victoria, Australia
- Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Yifang Li
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute and Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Yan Wang
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute and Department of Pharmacology, Monash University, Clayton, Victoria, Australia
| | - Robert E Widdop
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute and Department of Pharmacology, Monash University, Clayton, Victoria, Australia
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2
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Speck D, Kleinau G, Meininghaus M, Erbe A, Einfeldt A, Szczepek M, Scheerer P, Pütter V. Expression and Characterization of Relaxin Family Peptide Receptor 1 Variants. Front Pharmacol 2022; 12:826112. [PMID: 35153771 PMCID: PMC8832513 DOI: 10.3389/fphar.2021.826112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 12/31/2021] [Indexed: 12/31/2022] Open
Abstract
G-protein coupled receptors (GPCR) transduce extracellular stimuli into the cell interior and are thus centrally involved in almost all physiological-neuronal processes. This essential function and association with many diseases or pathological conditions explain why GPCRs are one of the priority targets in medical and pharmacological research, including structure determination. Despite enormous experimental efforts over the last decade, both the expression and purification of these membrane proteins remain elusive. This is attributable to specificities of each GPCR subtype and the finding of necessary experimental in vitro conditions, such as expression in heterologous cell systems or with accessory proteins. One of these specific GPCRs is the leucine-rich repeat domain (LRRD) containing GPCR 7 (LGR7), also termed relaxin family peptide receptor 1 (RXFP1). This receptor is characterized by a large extracellular region of around 400 amino acids constituted by several domains, a rare feature among rhodopsin-like (class A) GPCRs. In the present study, we describe the expression and purification of RXFP1, including the design of various constructs suitable for functional/biophysical studies and structure determination. Based on available sequence information, homology models, and modern biochemical and genetic tools, several receptor variations with different purification tags and fusion proteins were prepared and expressed in Sf9 cells (small-scale), followed by an analytic fluorescence-detection size-exclusion chromatography (F-SEC) to evaluate the constructs. The most promising candidates were expressed and purified on a large-scale, accompanied by ligand binding studies using surface plasmon resonance spectroscopy (SPR) and by determination of signaling capacities. The results may support extended studies on RXFP1 receptor constructs serving as targets for small molecule ligand screening or structural elucidation by protein X-ray crystallography or cryo-electron microscopy.
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Affiliation(s)
- David Speck
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Group Protein X-ray Crystallography & Signal Transduction, Berlin, Germany
| | - Gunnar Kleinau
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Group Protein X-ray Crystallography & Signal Transduction, Berlin, Germany
| | - Mark Meininghaus
- Bayer AG, Research and Development, Pharmaceuticals, Wuppertal, Germany
| | - Antje Erbe
- Bayer AG, Research and Development, Pharmaceuticals, Berlin, Germany
- NUVISAN ICB GmbH, Berlin, Germany
| | - Alexandra Einfeldt
- Bayer AG, Research and Development, Pharmaceuticals, Berlin, Germany
- NUVISAN ICB GmbH, Berlin, Germany
| | - Michal Szczepek
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Group Protein X-ray Crystallography & Signal Transduction, Berlin, Germany
| | - Patrick Scheerer
- Charité – Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Medical Physics and Biophysics, Group Protein X-ray Crystallography & Signal Transduction, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany
- *Correspondence: Patrick Scheerer, ; Vera Pütter,
| | - Vera Pütter
- Bayer AG, Research and Development, Pharmaceuticals, Berlin, Germany
- NUVISAN ICB GmbH, Berlin, Germany
- *Correspondence: Patrick Scheerer, ; Vera Pütter,
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3
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Wang JH, Nie WH, Shao XX, Li HZ, Hu MJ, Liu YL, Xu ZG, Guo ZY. Exploring electrostatic interactions of relaxin family peptide receptor 3 and 4 with ligands using a NanoBiT-based binding assay. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:776-786. [DOI: 10.1016/j.bbamem.2019.01.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2018] [Revised: 01/16/2019] [Accepted: 01/21/2019] [Indexed: 12/15/2022]
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4
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Hossain MA, Bathgate RAD. Challenges in the design of insulin and relaxin/insulin-like peptide mimetics. Bioorg Med Chem 2017; 26:2827-2841. [PMID: 28988628 DOI: 10.1016/j.bmc.2017.09.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/19/2017] [Accepted: 09/19/2017] [Indexed: 12/20/2022]
Abstract
Peptidomimetics are designed to overcome the poor pharmacokinetics and pharmacodynamics associated with the native peptide or protein on which they are based. The design of peptidomimetics starts from developing structure-activity relationships of the native ligand-target pair that identify the key residues that are responsible for the biological effect of the native peptide or protein. Then minimization of the structure and introduction of constraints are applied to create the core active site that can interact with the target with high affinity and selectivity. Developing peptidomimetics is not trivial and often challenging, particularly when peptides' interaction mechanism with their target is complex. This review will discuss the challenges of developing peptidomimetics of therapeutically important insulin superfamily peptides, particularly those which have two chains (A and B) and three disulfide bonds and whose receptors are known, namely insulin, H2 relaxin, H3 relaxin, INSL3 and INSL5.
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Affiliation(s)
- Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC 3010, Australia; School of Chemistry, University of Melbourne, Parkville, VIC 3010, Australia.
| | - Ross A D Bathgate
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC 3010, Australia; Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC 3010, Australia.
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5
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Sanchez-Mas J, Lax A, Asensio-Lopez MC, Lencina M, Fernandez-Del Palacio MJ, Soriano-Filiu A, de Boer RA, Pascual-Figal DA. Early Anti-inflammatory and Pro-angiogenic Myocardial Effects of Intravenous Serelaxin Infusion for 72 H in an Experimental Rat Model of Acute Myocardial Infarction. J Cardiovasc Transl Res 2017; 10:460-469. [PMID: 28718055 DOI: 10.1007/s12265-017-9761-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 06/26/2017] [Indexed: 01/24/2023]
Abstract
Sprague Dawley rats were subjected to acute myocardial infarction (AMI) by permanent ligation of the left anterior descending coronary artery. At the time of AMI, a subcutaneous mini-osmotic pump was implanted and animals were randomized into three groups, according to the intravenous therapy received during the first 72 h: placebo-treated (saline), serelaxin10-treated (SRLX10 = 10 μg/kg/day), or serelaxin30-treated (SRLX30 = 30 μg/kg/day). Treatment with SRLX30 reduced the expression of inflammatory cytokines and chemokines, as well as the infiltration of macrophages, and increased the expression of pro-angiogenic markers and vessel density in the infarcted myocardium after 7 days. SRLX30 did not reduce early myocardial fibrosis but reduced myocardial levels of sST2 and galectin-3. No significant effects were observed with SRLX10 treatment. A significant correlation was observed between plasma levels of serelaxin and effect measures. The results suggest serelaxin has a protective effect in early processes of cardiac remodeling after AMI.
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Affiliation(s)
- Jesus Sanchez-Mas
- Instituto Murciano de Investigación Biomédica (IMIB), Facultad de Medicina, University of Murcia, Murcia, Spain.,Departamento de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad CEU Cardenal Herrera, Moncada, Spain
| | - Antonio Lax
- Instituto Murciano de Investigación Biomédica (IMIB), Facultad de Medicina, University of Murcia, Murcia, Spain
| | - Mari C Asensio-Lopez
- Instituto Murciano de Investigación Biomédica (IMIB), Facultad de Medicina, University of Murcia, Murcia, Spain
| | - Miriam Lencina
- Pathological Anatomy Department, Hospital Universitario Virgen de la Arrixaca, Murcia, Spain
| | | | - Angela Soriano-Filiu
- Instituto Murciano de Investigación Biomédica (IMIB), Facultad de Medicina, University of Murcia, Murcia, Spain
| | - Rudolf A de Boer
- Department of Cardiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Domingo A Pascual-Figal
- Instituto Murciano de Investigación Biomédica (IMIB), Facultad de Medicina, University of Murcia, Murcia, Spain. .,Cardiology Department, Hospital Universitario Virgen de la Arrixaca, LAIB, Room 2.52, Av. Buenavista s/n, 30120, Murcia, Spain. .,CIBER in Cardiovascular Diseases (CIBERCV), Madrid, Spain.
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6
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Wei D, Hu MJ, Shao XX, Wang JH, Nie WH, Liu YL, Xu ZG, Guo ZY. Development of a selective agonist for relaxin family peptide receptor 3. Sci Rep 2017; 7:3230. [PMID: 28607363 PMCID: PMC5468247 DOI: 10.1038/s41598-017-03465-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 04/27/2017] [Indexed: 12/01/2022] Open
Abstract
Relaxin family peptides perform a variety of biological functions by activating four G protein-coupled receptors, namely RXFP1–4. Among these receptors, RXFP3 lacks a specific natural or synthetic agonist at present. A previously designed chimeric R3/I5 peptide, consisting of the B-chain of relaxin-3 and the A-chain of INSL5, displays equal activity towards the homologous RXFP3 and RXFP4. To increase its selectivity towards RXFP3, in the present study we conducted extensive mutagenesis around the B-chain C-terminal region of R3/I5. Decreasing or increasing the peptide length around the B23–B25 position dramatically lowered the activation potency of R3/I5 towards both RXFP3 and RXFP4. Substitution of B23Gly with Ala or Ser converted R3/I5 from an efficient agonist to a strong antagonist for RXFP3, but the mutants retained considerable activation potency towards RXFP4. Substitution of B24Gly increased the selectivity of R3/I5 towards RXFP3 over the homologous RXFP4. The best mutant, [G(B24)S]R3/I5, displayed 20-fold higher activation potency towards RXFP3 than towards RXFP4, meanwhile retained full activation potency at RXFP3. Thus, [G(B24)S]R3/I5 is the best RXFP3-selective agonist known to date. It is a valuable tool for investigating the physiological functions of RXFP3, and also a suitable template for developing RXFP3-specific agonists in future.
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Affiliation(s)
- Dian Wei
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Meng-Jun Hu
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xiao-Xia Shao
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jia-Hui Wang
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Wei-Han Nie
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Ya-Li Liu
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Zeng-Guang Xu
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Zhan-Yun Guo
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China.
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7
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Samuel CS, Royce SG, Hewitson TD, Denton KM, Cooney TE, Bennett RG. Anti-fibrotic actions of relaxin. Br J Pharmacol 2017; 174:962-976. [PMID: 27250825 PMCID: PMC5406285 DOI: 10.1111/bph.13529] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 05/19/2016] [Accepted: 05/23/2016] [Indexed: 12/19/2022] Open
Abstract
Fibrosis refers to the hardening or scarring of tissues that usually results from aberrant wound healing in response to organ injury, and its manifestations in various organs have collectively been estimated to contribute to around 45-50% of deaths in the Western world. Despite this, there is currently no effective cure for the tissue structural and functional damage induced by fibrosis-related disorders. Relaxin meets several criteria of an effective anti-fibrotic based on its specific ability to inhibit pro-fibrotic cytokine and/or growth factor-mediated, but not normal/unstimulated, fibroblast proliferation, differentiation and matrix production. Furthermore, relaxin augments matrix degradation through its ability to up-regulate the release and activation of various matrix-degrading matrix metalloproteinases and/or being able to down-regulate tissue inhibitor of metalloproteinase activity. Relaxin can also indirectly suppress fibrosis through its other well-known (anti-inflammatory, antioxidant, anti-hypertrophic, anti-apoptotic, angiogenic, wound healing and vasodilator) properties. This review will outline the organ-specific and general anti-fibrotic significance of exogenously administered relaxin and its mechanisms of action that have been documented in various non-reproductive organs such as the cardiovascular system, kidney, lung, liver, skin and tendons. In addition, it will outline the influence of sex on relaxin's anti-fibrotic actions, highlighting its potential as an emerging anti-fibrotic therapeutic. LINKED ARTICLES This article is part of a themed section on Recent Progress in the Understanding of Relaxin Family Peptides and their Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.10/issuetoc.
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Affiliation(s)
- C S Samuel
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of PharmacologyMonash UniversityMelbourneVic.Australia
| | - S G Royce
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of PharmacologyMonash UniversityMelbourneVic.Australia
| | - T D Hewitson
- Department of NephrologyRoyal Melbourne HospitalMelbourneVic.Australia
| | - K M Denton
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of PhysiologyMonash UniversityMelbourneVic.Australia
| | - T E Cooney
- University of Pittsburgh Medical Centre (UPMC) HamotEriePAUSA
| | - R G Bennett
- Research Service 151VA Nebraska‐Western Iowa Health Care SystemOmahaNEUSA
- Department of Internal MedicineUniversity of Nebraska Medical CenterOmahaNEUSA
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8
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Patil NA, Rosengren KJ, Separovic F, Wade JD, Bathgate RAD, Hossain MA. Relaxin family peptides: structure-activity relationship studies. Br J Pharmacol 2017; 174:950-961. [PMID: 27922185 DOI: 10.1111/bph.13684] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/25/2016] [Accepted: 11/28/2016] [Indexed: 12/21/2022] Open
Abstract
The human relaxin peptide family consists of seven cystine-rich peptides, four of which are known to signal through relaxin family peptide receptors, RXFP1-4. As these peptides play a vital role physiologically and in various diseases, they are of considerable importance for drug discovery and development. Detailed structure-activity relationship (SAR) studies towards understanding the role of important residues in each of these peptides have been reported over the years and utilized for the design of antagonists and minimized agonist variants. This review summarizes the current knowledge of the SAR of human relaxin 2 (H2 relaxin), human relaxin 3 (H3 relaxin), human insulin-like peptide 3 (INSL3) and human insulin-like peptide 5 (INSL5). LINKED ARTICLES This article is part of a themed section on Recent Progress in the Understanding of Relaxin Family Peptides and their Receptors. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.10/issuetoc.
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Affiliation(s)
- Nitin A Patil
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.,School of Chemistry, University of Melbourne, Parkville, VIC, Australia
| | - K Johan Rosengren
- Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia
| | - Frances Separovic
- School of Chemistry, University of Melbourne, Parkville, VIC, Australia
| | - John D Wade
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.,School of Chemistry, University of Melbourne, Parkville, VIC, Australia
| | - Ross A D Bathgate
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, VIC, Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia.,School of Chemistry, University of Melbourne, Parkville, VIC, Australia
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9
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Hu MJ, Shao XX, Wang JH, Wei D, Guo YQ, Liu YL, Xu ZG, Guo ZY. Mechanism for insulin-like peptide 5 distinguishing the homologous relaxin family peptide receptor 3 and 4. Sci Rep 2016; 6:29648. [PMID: 27404393 PMCID: PMC4939597 DOI: 10.1038/srep29648] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Accepted: 06/07/2016] [Indexed: 12/11/2022] Open
Abstract
The relaxin family peptides play a variety of biological functions by activating four G protein-coupled receptors, RXFP1-4. Among them, insulin-like peptide 5 (INSL5) and relaxin-3 share the highest sequence homology, but they have distinct receptor preference: INSL5 can activate RXFP4 only, while relaxin-3 can activate RXFP3, RXFP4, and RXFP1. Previous studies suggest that the A-chain is responsible for their different selectivity for RXFP1. However, the mechanism by which INSL5 distinguishes the homologous RXFP4 and RXFP3 remains unknown. In the present work, we chemically evolved INSL5 in vitro to a strong agonist of both RXFP4 and RXFP3 through replacement of its five B-chain residues with the corresponding residues of relaxin-3. We identified four determinants (B2Glu, B9Leu, B17Tyr, and a rigid B-chain C-terminus) on INSL5 that are responsible for its inactivity at RXFP3. In reverse experiments, we grafted these determinants onto a chimeric R3/I5 peptide, which contains the B-chain of relaxin-3 and the A-chain of INSL5, and retains full activation potency at RXFP3 and RXFP4. All resultant R3/I5 mutants retained high activation potency towards RXFP4, but most displayed significantly decreased or even abolished activation potency towards RXFP3, confirming the role of these four INSL5 determinants in distinguishing RXFP4 from RXFP3.
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Affiliation(s)
- Meng-Jun Hu
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Xiao-Xia Shao
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Jia-Hui Wang
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Dian Wei
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Yu-Qi Guo
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Ya-Li Liu
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Zeng-Guang Xu
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
| | - Zhan-Yun Guo
- Research Centre for Translational Medicine at East Hospital, College of Life Sciences and Technology, Tongji University, Shanghai, China
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10
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Sethi A, Bruell S, Patil N, Hossain MA, Scott DJ, Petrie EJ, Bathgate RAD, Gooley PR. The complex binding mode of the peptide hormone H2 relaxin to its receptor RXFP1. Nat Commun 2016; 7:11344. [PMID: 27088579 PMCID: PMC4837482 DOI: 10.1038/ncomms11344] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/16/2016] [Indexed: 11/20/2022] Open
Abstract
H2 relaxin activates the relaxin family peptide receptor-1 (RXFP1), a class A G-protein coupled receptor, by a poorly understood mechanism. The ectodomain of RXFP1 comprises an N-terminal LDLa module, essential for activation, tethered to a leucine-rich repeat (LRR) domain by a 32-residue linker. H2 relaxin is hypothesized to bind with high affinity to the LRR domain enabling the LDLa module to bind and activate the transmembrane domain of RXFP1. Here we define a relaxin-binding site on the LDLa-LRR linker, essential for the high affinity of H2 relaxin for the ectodomain of RXFP1, and show that residues within the LDLa-LRR linker are critical for receptor activation. We propose H2 relaxin binds and stabilizes a helical conformation of the LDLa-LRR linker that positions residues of both the linker and the LDLa module to bind the transmembrane domain and activate RXFP1. The mechanism by which relaxin activates the relaxin family peptide receptor-1 is poorly understood. Here, Sethi et al. identify a relaxin binding site in an extracellular linker between the LDLa and LRR domains and propose that relaxin binding stabilizes a helical conformation that leads to receptor activation.
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Affiliation(s)
- Ashish Sethi
- Department of Biochemistry &Molecular Biology, The University of Melbourne, Victoria 3010, Australia.,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Shoni Bruell
- Department of Biochemistry &Molecular Biology, The University of Melbourne, Victoria 3010, Australia.,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia.,Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Nitin Patil
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.,School of Chemistry, The University of Melbourne, Victoria 3010, Australia
| | - Mohammed Akhter Hossain
- School of Chemistry, The University of Melbourne, Victoria 3010, Australia.,Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Daniel J Scott
- Department of Biochemistry &Molecular Biology, The University of Melbourne, Victoria 3010, Australia.,Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Emma J Petrie
- Department of Biochemistry &Molecular Biology, The University of Melbourne, Victoria 3010, Australia.,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
| | - Ross A D Bathgate
- Department of Biochemistry &Molecular Biology, The University of Melbourne, Victoria 3010, Australia.,Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Paul R Gooley
- Department of Biochemistry &Molecular Biology, The University of Melbourne, Victoria 3010, Australia.,Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Victoria 3010, Australia
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11
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Hossain MA, Kocan M, Yao ST, Royce SG, Nair VB, Siwek C, Patil NA, Harrison IP, Rosengren KJ, Selemidis S, Summers RJ, Wade JD, Bathgate RAD, Samuel CS. A single-chain derivative of the relaxin hormone is a functionally selective agonist of the G protein-coupled receptor, RXFP1. Chem Sci 2016; 7:3805-3819. [PMID: 30155023 PMCID: PMC6013806 DOI: 10.1039/c5sc04754d] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/24/2016] [Indexed: 11/24/2022] Open
Abstract
A single-chain derivative of the relaxin hormone ameliorates fibrosis without side-effects.
Human gene-2 relaxin (H2 relaxin) is a pleiotropic hormone with powerful vasodilatory and anti-fibrotic properties which has led to its clinical evaluation and provisional FDA approval as a treatment for acute heart failure. The diverse effects of H2 relaxin are mediated via its cognate G protein coupled-receptor (GPCR), Relaxin Family Peptide Receptor (RXFP1), leading to stimulation of a combination of cell signalling pathways that includes cyclic adenosine monophosphate (cAMP) and extracellular-signal-regulated kinases (ERK)1/2. However, its complex two-chain (A and B), disulfide-rich insulin-like structure is a limitation to its facile preparation, availability and affordability. Furthermore, its strong activation of cAMP signaling is likely responsible for reported detrimental tumor-promoting actions that may preclude long-term use of this drug for treating human disease. Here we report the design and synthesis of a H2 relaxin B-chain-only analogue, B7-33, which was shown to bind to RXFP1 and preferentially activate the pERK pathway over cAMP in cells that endogenously expressed RXFP1. Thus, B7-33 represents the first functionally selective agonist of the complex GPCR, RXFP1. Importantly, this small peptide agonist prevented or reversed organ fibrosis and dysfunction in three pre-clinical rodent models of heart or lung disease with similar potency to H2 relaxin. The molecular mechanism behind the strong anti-fibrotic actions of B7-33 involved its activation of RXFP1-angiotensin II type 2 receptor heterodimers that induced selective downstream signaling of pERK1/2 and the collagen-degrading enzyme, matrix metalloproteinase (MMP)-2. Furthermore, in contrast to H2 relaxin, B7-33 did not promote prostate tumor growth in vivo. Our results represent the first known example of the minimisation of a two-chain cyclic insulin-like peptide to a single-chain linear peptide that retains potent beneficial agonistic effects.
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Affiliation(s)
- Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Victoria 3010 , Australia . ; ; .,School of Chemistry , The University of Melbourne , Victoria 3010 , Australia
| | - Martina Kocan
- Monash Institute of Pharmaceutical Sciences , Monash University , Victoria , Australia
| | - Song T Yao
- Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Victoria 3010 , Australia . ; ;
| | - Simon G Royce
- Cardiovascular Disease Program , Biomedicine Discovery Institute and Department of Pharmacology , Monash University , Victoria , Australia .
| | - Vinojini B Nair
- Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Victoria 3010 , Australia . ; ; .,School of Chemistry , The University of Melbourne , Victoria 3010 , Australia
| | - Christopher Siwek
- Monash Institute of Pharmaceutical Sciences , Monash University , Victoria , Australia
| | - Nitin A Patil
- Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Victoria 3010 , Australia . ; ; .,School of Chemistry , The University of Melbourne , Victoria 3010 , Australia
| | - Ian P Harrison
- Cardiovascular Disease Program , Biomedicine Discovery Institute and Department of Pharmacology , Monash University , Victoria , Australia .
| | - K Johan Rosengren
- The University of Queensland , School of Biomedical Sciences , Brisbane , QLD 4072 , Australia
| | - Stavros Selemidis
- Cardiovascular Disease Program , Biomedicine Discovery Institute and Department of Pharmacology , Monash University , Victoria , Australia .
| | - Roger J Summers
- Monash Institute of Pharmaceutical Sciences , Monash University , Victoria , Australia
| | - John D Wade
- Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Victoria 3010 , Australia . ; ; .,School of Chemistry , The University of Melbourne , Victoria 3010 , Australia
| | - Ross A D Bathgate
- Florey Institute of Neuroscience and Mental Health , The University of Melbourne , Victoria 3010 , Australia . ; ; .,Department of Biochemistry , The University of Melbourne , Victoria 3010 , Australia
| | - Chrishan S Samuel
- Cardiovascular Disease Program , Biomedicine Discovery Institute and Department of Pharmacology , Monash University , Victoria , Australia .
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12
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Dschietzig TB, Krause-Relle K, Hennequin M, von Websky K, Rahnenführer J, Ruppert J, Grön HJ, Armbruster FP, Bathgate RAD, Aschenbach JR, Forssmann WG, Hocher B. Relaxin-2 does not ameliorate nephropathy in an experimental model of type-1 diabetes. Kidney Blood Press Res 2016; 40:77-88. [PMID: 25791819 DOI: 10.1159/000368484] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS In diabetic nephropathy (DN), the current angiotensin-II-blocking pharmacotherapy is frequently failing. For diabetic cardiomyopathy (DC), there is no specific remedy available. Relaxin-2 (Rlx) - an anti-fibrotic, anti-inflammatory, and vasoprotecting peptide – is a candidate drug for both. METHODS Low-dose (32 μg/kg/day) and high-dose (320 μg/kg/day) Rlx were tested against vehicle (n = 20 each) and non-diabetic controls (n = 14) for 12 weeks in a model of type-1 diabetes induced in endothelial nitric oxide synthase knock-out (eNOS-KO) mice by intraperitoneal injection of streptozotocin. RESULTS Diabetic animals showed normal plasma creatinine, markedly increased albuminuria and urinary malonyldialdehyde, elevated relative kidney weight, glomerulosclerosis, and increased glomerular size, but no relevant interstitial fibrosis. Neither dose of Rlx affected these changes although the drug was active and targeted plasma levels were achieved. Of note, we found no activation of the renal TGF-β pathway in this model. In the hearts of diabetic animals, no fibrotic alterations indicative of DC could be determined which precluded testing of the initial hypothesis. CONCLUSIONS We investigated a model showing early DN without overt tubulointerstitial fibrosis and activation of the TGF-β-Smad-2/3 pathway. In this model, Rlx proved ineffective; however, the same may not apply to other models and types of diabetes.
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13
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Halls ML, Bathgate RAD, Sutton SW, Dschietzig TB, Summers RJ. International Union of Basic and Clinical Pharmacology. XCV. Recent advances in the understanding of the pharmacology and biological roles of relaxin family peptide receptors 1-4, the receptors for relaxin family peptides. Pharmacol Rev 2015; 67:389-440. [PMID: 25761609 DOI: 10.1124/pr.114.009472] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Relaxin, insulin-like peptide 3 (INSL3), relaxin-3, and INSL5 are the cognate ligands for the relaxin family peptide (RXFP) receptors 1-4, respectively. RXFP1 activates pleiotropic signaling pathways including the signalosome protein complex that facilitates high-sensitivity signaling; coupling to Gα(s), Gα(i), and Gα(o) proteins; interaction with glucocorticoid receptors; and the formation of hetero-oligomers with distinctive pharmacological properties. In addition to relaxin-related ligands, RXFP1 is activated by Clq-tumor necrosis factor-related protein 8 and by small-molecular-weight agonists, such as ML290 [2-isopropoxy-N-(2-(3-(trifluoromethylsulfonyl)phenylcarbamoyl)phenyl)benzamide], that act allosterically. RXFP2 activates only the Gα(s)- and Gα(o)-coupled pathways. Relaxin-3 is primarily a neuropeptide, and its cognate receptor RXFP3 is a target for the treatment of depression, anxiety, and autism. A variety of peptide agonists, antagonists, biased agonists, and an allosteric modulator target RXFP3. Both RXFP3 and the related RXFP4 couple to Gα(i)/Gα(o) proteins. INSL5 has the properties of an incretin; it is secreted from the gut and is orexigenic. The expression of RXFP4 in gut, adipose tissue, and β-islets together with compromised glucose tolerance in INSL5 or RXFP4 knockout mice suggests a metabolic role. This review focuses on the many advances in our understanding of RXFP receptors in the last 5 years, their signal transduction mechanisms, the development of novel compounds that target RXFP1-4, the challenges facing the field, and current prospects for new therapeutics.
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Affiliation(s)
- Michelle L Halls
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia (M.L.H., R.J.S.); Neuropeptides Division, Florey Institute of Neuroscience and Mental Health and Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia (R.A.D.B.); Neuroscience Drug Discovery, Janssen Research & Development, LLC, San Diego, California (S.W.S.); Immundiagnostik AG, Bensheim, Germany (T.B.D.); and Charité-University Medicine Berlin, Campus Mitte, Medical Clinic for Cardiology and Angiology, Berlin, Germany (T.B.D.)
| | - Ross A D Bathgate
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia (M.L.H., R.J.S.); Neuropeptides Division, Florey Institute of Neuroscience and Mental Health and Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia (R.A.D.B.); Neuroscience Drug Discovery, Janssen Research & Development, LLC, San Diego, California (S.W.S.); Immundiagnostik AG, Bensheim, Germany (T.B.D.); and Charité-University Medicine Berlin, Campus Mitte, Medical Clinic for Cardiology and Angiology, Berlin, Germany (T.B.D.)
| | - Steve W Sutton
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia (M.L.H., R.J.S.); Neuropeptides Division, Florey Institute of Neuroscience and Mental Health and Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia (R.A.D.B.); Neuroscience Drug Discovery, Janssen Research & Development, LLC, San Diego, California (S.W.S.); Immundiagnostik AG, Bensheim, Germany (T.B.D.); and Charité-University Medicine Berlin, Campus Mitte, Medical Clinic for Cardiology and Angiology, Berlin, Germany (T.B.D.)
| | - Thomas B Dschietzig
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia (M.L.H., R.J.S.); Neuropeptides Division, Florey Institute of Neuroscience and Mental Health and Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia (R.A.D.B.); Neuroscience Drug Discovery, Janssen Research & Development, LLC, San Diego, California (S.W.S.); Immundiagnostik AG, Bensheim, Germany (T.B.D.); and Charité-University Medicine Berlin, Campus Mitte, Medical Clinic for Cardiology and Angiology, Berlin, Germany (T.B.D.)
| | - Roger J Summers
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Parkville, Victoria, Australia (M.L.H., R.J.S.); Neuropeptides Division, Florey Institute of Neuroscience and Mental Health and Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria, Australia (R.A.D.B.); Neuroscience Drug Discovery, Janssen Research & Development, LLC, San Diego, California (S.W.S.); Immundiagnostik AG, Bensheim, Germany (T.B.D.); and Charité-University Medicine Berlin, Campus Mitte, Medical Clinic for Cardiology and Angiology, Berlin, Germany (T.B.D.)
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14
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Hossain MA, Haugaard-Kedström LM, Rosengren KJ, Bathgate RAD, Wade JD. Chemically synthesized dicarba H2 relaxin analogues retain strong RXFP1 receptor activity but show an unexpected loss of in vitro serum stability. Org Biomol Chem 2015; 13:10895-903. [PMID: 26368576 DOI: 10.1039/c5ob01539a] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Peptides and proteins are now acknowledged as viable alternatives to small molecules as potential therapeutic agents. A primary limitation to their more widespread acceptance is their generally short in vivo half-lives due to serum enzyme susceptibility and rapid renal clearance. Numerous chemical approaches to address this concern have been undertaken in recent years. The replacement of disulfide bonds with non-reducible elements has been demonstrated to be one effective means by eliminating the deleterious effect of serum reductases. In particular, substitution with dicarba bonds via ring closure metathesis has been increasingly applied to many bioactive cystine-rich peptides. We used this approach for the replacement of the A-chain intramolecular disulfide bond of human relaxin 2 (H2 relaxin), an insulin-like peptide that has important regulatory roles in cardiovascular and connective tissue homeostasis that has led to successful Phase IIIa clinical trials for the treatment of acute heart failure. Use of efficient solid phase synthesis of the two peptide chains was followed by on-resin ring closure metathesis and formation of the dicarba bond within the A-chain and then by off-resin combination with the B-chain via sequential directed inter-chain disulfide bond formation. After purification and comprehensive chemical characterization, the two isomeric synthetic H2 relaxin analogues were shown to retain near-equipotent RXFP1 receptor binding and activation propensity. Unexpectedly, the in vitro serum stability of the analogues was greatly reduced compared with the native peptide. Circular dichroism spectroscopy studies showed subtle differences in the secondary structures between dicarba analogues and H2 relaxin suggesting that, although the overall fold is retained, it may be destabilized which could account for rapid degradation of dicarba analogues in serum. Caution is therefore recommended when using ring closure metathesis as a general approach to enhance peptide stability.
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Affiliation(s)
- Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.
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15
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Haugaard-Kedström LM, Hossain MA, Daly NL, Bathgate RAD, Rinderknecht E, Wade JD, Craik DJ, Rosengren KJ. Solution structure, aggregation behavior, and flexibility of human relaxin-2. ACS Chem Biol 2015; 10:891-900. [PMID: 25547165 DOI: 10.1021/cb500918v] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Relaxin is a member of the relaxin/insulin peptide hormone superfamily and is characterized by a two-chain structure constrained by three disulfide bonds. Relaxin is a pleiotropic hormone and involved in a number of physiological and pathogenic processes, including collagen and cardiovascular regulation and tissue remodelling during pregnancy and cancer. Crystallographic and ultracentrifugation experiments have revealed that the human form of relaxin, H2 relaxin, self-associates into dimers, but the significance of this is poorly understood. Here, we present the NMR structure of a monomeric, amidated form of H2 relaxin and compare its features and behavior in solution to those of native H2 relaxin. The overall structure of H2 relaxin is retained in the monomeric form. H2 relaxin amide is fully active at the relaxin receptor RXFP1 and thus dimerization is not required for biological activity. Analysis of NMR chemical shifts and relaxation parameters identified internal motion in H2 relaxin at the pico-nanosecond and milli-microsecond time scales, which is commonly seen in other relaxin and insulin peptides and might be related to function.
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Affiliation(s)
| | | | - Norelle L. Daly
- Centre for
Biodiscovery and Molecular Development of Therapeutics, AITHM, James Cook University, Cairns, Queensland 4878, Australia
| | | | - Ernst Rinderknecht
- Corthera, c/o
Novartis Corporation, San Carlos, California 94070, United States
| | | | | | - K. Johan Rosengren
- School
of Natural Sciences, Linnaeus University, SE-391 82 Kalmar, Sweden
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16
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Hossain MA, Wade JD. Synthetic relaxins. Curr Opin Chem Biol 2014; 22:47-55. [DOI: 10.1016/j.cbpa.2014.09.014] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/12/2014] [Accepted: 09/12/2014] [Indexed: 12/01/2022]
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17
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Abstract
Over the past few decades, research on the peptide hormone, relaxin, has significantly improved our understanding of its biological actions under physiological and diseased conditions. This has facilitated the conducting of clinical trials to explore the use of serelaxin (human recombinant relaxin). Acute heart failure (AHF) is a very difficult to treat clinical entity, with limited success so far in developing new drugs to combat it. A recent phase-III RELAX-AHF trial using serelaxin therapy given during hospitalization revealed acute (ameliorated dyspnea) and chronic (improved 180-day survival) effects. Although these findings support a substantial improvement by serelaxin therapy over currently available therapies for AHF, they also raise key questions and stimulate new hypotheses. To facilitate the development of serelaxin as a new drug for heart disease, joint efforts of clinicians, research scientists and pharmacological industries are necessary to study these questions and hypotheses. In this review, after providing a brief summary of clinical findings and the pathophysiology of AHF, we present a working hypothesis of the mechanisms responsible for the observed efficacy of serelaxin in AHF patients. The existing clinical and preclinical data supporting our hypotheses are summarized and discussed. The development of serelaxin as a drug provides an excellent example of the bilateral nature of translational research.
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Affiliation(s)
- Xiao-Jun Du
- Baker IDI Heart and Diabetes Institute, Monash University
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18
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Chan LJ, Smith CM, Chua BE, Lin F, Bathgate RAD, Separovic F, Gundlach AL, Hossain MA, Wade JD. Synthesis of fluorescent analogs of relaxin family peptides and their preliminary in vitro and in vivo characterization. Front Chem 2013; 1:30. [PMID: 24790958 PMCID: PMC3982560 DOI: 10.3389/fchem.2013.00030] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 11/18/2013] [Indexed: 12/13/2022] Open
Abstract
Relaxin, a heterodimeric polypeptide hormone, is a key regulator of collagen metabolism and multiple vascular control pathways in humans and rodents. Its actions are mediated via its cognate G-protein-coupled receptor, RXFP1 although it also "pharmacologically" activates RXFP2, the receptor for the related, insulin-like peptide 3 (INSL3), which has specific actions on reproduction and bone metabolism. Therefore, experimental tools to facilitate insights into the distinct biological actions of relaxin and INSL3 are required, particularly for studies of tissues containing both RXFP1 and RXFP2. Here, we chemically functionalized human (H2) relaxin, the RXFP1-selective relaxin analog H2:A(4-24)(F23A), and INSL3 to accommodate a fluorophore without marked reduction in binding or activation propensity. Chemical synthesis of the two chains for each peptide was followed by sequential regioselective formation of their three disulfide bonds. Click chemistry conjugation of Cy5.5 at the B-chain N-terminus, with conservation of the disulfide bonds, yielded analogs displaying appropriate selective binding affinity and ability to activate RXFP1 and/or RXFP2 in vitro. The in vivo biological activity of Cy5.5-H2 relaxin and Cy5.5-H2:A(4-24)(F23A) was confirmed in mice, as acute intracerebroventricular (icv) infusion of these peptides (but not Cy5.5-INSL3) stimulated water drinking, an established behavioral response elicited by central RXFP1 activation. The central distribution of Cy5.5-conjugated peptides was examined in mice killed 30 min after infusion, revealing higher fluorescence within brain tissue near-adjacent to the cerebral ventricle walls relative to deeper brain areas. Production of fluorophore-conjugated relaxin family peptides will facilitate future pharmacological studies to probe the function of H2 relaxin/RXFP1 and INSL3/RXFP2 signaling in vivo while tracking their distribution following central or peripheral administration.
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Affiliation(s)
- Linda J Chan
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; School of Chemistry, The University of Melbourne VIC, Australia
| | - Craig M Smith
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; Florey Department of Neuroscience and Mental Health, The University of Melbourne VIC, Australia
| | - Berenice E Chua
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia
| | - Feng Lin
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia
| | - Ross A D Bathgate
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; Florey Department of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; Department of Biochemistry and Molecular Biology, The University of Melbourne VIC, Australia
| | | | - Andrew L Gundlach
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; Florey Department of Neuroscience and Mental Health, The University of Melbourne VIC, Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; School of Chemistry, The University of Melbourne VIC, Australia ; Florey Department of Neuroscience and Mental Health, The University of Melbourne VIC, Australia
| | - John D Wade
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne VIC, Australia ; School of Chemistry, The University of Melbourne VIC, Australia ; Florey Department of Neuroscience and Mental Health, The University of Melbourne VIC, Australia
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