1
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Wu H, Praveen P, Handley TNG, Chandrashekar C, Cummins SF, Bathgate RAD, Hossain MA. Total Chemical Synthesis of Aggregation-Prone Disulfide-Rich Starfish Peptides. Chemistry 2024; 30:e202400933. [PMID: 38609334 DOI: 10.1002/chem.202400933] [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: 03/06/2024] [Revised: 04/11/2024] [Accepted: 04/12/2024] [Indexed: 04/14/2024]
Abstract
A relaxin-like gonad-stimulating peptide (RGP), Aso-RGP, featuring six cysteine residues, was identified in the Crown-of-Thorns Starfish (COTS, Acanthaster cf. solaris) and initially produced through recombinant yeast expression. This method yielded a single-chain peptide with an uncleaved C-peptide (His Tag) and suboptimal purity. Our objective was to chemically synthesize Aso-RGP in its mature form, comprising two chains (A and B) and three disulfide bridges, omitting the C-peptide. Furthermore, we aimed to synthesize a newly identified relaxin-like peptide, Aso-RLP2, from COTS, which had not been previously synthesized. This paper reports the first total chemical synthesis of Aso-RGP and Aso-RLP2. Aso-RGP synthesis proceeded without major issues, whereas the A-chain of Aso-RLP2, in its reduced and unfolded state with two free thiols, presented considerable challenges. These were initially marked by "messy" RP-HPLC profiles, typically indicative of synthesis failure. Surprisingly, oxidizing the A-chain significantly improved the RP-HPLC profile, revealing the main issue was not synthesis failure but the peptide's aggregation tendency, which initially obscured analysis. This discovery highlights the critical need to account for aggregation in peptide synthesis and analysis. Ultimately, our efforts led to the successful synthesis of both peptides with purities exceeding 95 %.
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Affiliation(s)
- Hongkang Wu
- The Florey, The University of Melbourne, Victoria, Australia
| | - Praveen Praveen
- The Florey, The University of Melbourne, Victoria, Australia
| | | | | | - Scott F Cummins
- Centre for Bioinnovation, University of the Sunshine Coast, Queensland, Australia
- School of Science, Technology and Engineering, University of the Sunshine Coast, Queensland, Australia
| | - Ross A D Bathgate
- The Florey, The University of Melbourne, Victoria, Australia
- Department of Biochemistry and Pharmacology, The University of Melbourne, Victoria, Australia
| | - Mohammed Akhter Hossain
- The Florey, The University of Melbourne, Victoria, Australia
- School of Chemistry, The University of Melbourne, Victoria, Australia
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2
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Wu H, Handley TNG, Hoare BL, Hartono HA, Scott DJ, Chalmers DK, Bathgate RAD, Hossain MA. Developing insulin-like peptide 5-based antagonists for the G protein-coupled receptor, RXFP4. Biochem Pharmacol 2024; 224:116239. [PMID: 38679208 DOI: 10.1016/j.bcp.2024.116239] [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: 01/16/2024] [Revised: 04/05/2024] [Accepted: 04/25/2024] [Indexed: 05/01/2024]
Abstract
Human insulin-like peptide 5 (INSL5) is a gut hormone produced by colonic L-cells, and its biological functions are mediated by Relaxin Family Peptide Receptor 4 (RXFP4). Our preliminary data indicated that RXFP4 agonists are potential drug leads for the treatment of constipation. More recently, we designed and developed a novel RXFP4 antagonist, A13-nR that was shown to block agonist-induced activity in cells and animal models. We showed that A13-nR was able to block agonist-induced increases in colon motility in mice of both genders that express the receptor, RXFP4. Our data also showed that colorectal propulsion induced by intracolonic administration of short-chain fatty acids was antagonized by A13-nR. Therefore, A13-nR is an important research tool and potential drug lead for the treatment of colon motility disorders, such as bacterial diarrhea. However, A13-nR acted as a partial agonist at high concentrations in vitro and demonstrated modest antagonist potency (∼35 nM). Consequently, the primary objective of this study is to pinpoint novel modifications to A13-nR that eliminate partial agonist effects while preserving or augmenting antagonist potency. In this work, we detail the creation of a series of A13-nR-modified analogues, among which analogues 3, 4, and 6 demonstrated significantly improved RXFP4 affinity (∼3 nM) with reduced partial agonist activity, enhanced antagonist potency (∼10 nM) and maximum agonist inhibition (∼80 %) when compared with A13-nR. These compounds have potential as candidates for further preclinical evaluations, marking a significant stride toward innovative therapeutics for colon motility disorders.
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Affiliation(s)
- Hongkang Wu
- The Florey, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Thomas N G Handley
- The Florey, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Bradley L Hoare
- The Florey, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Herodion A Hartono
- Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Victoria 3052, Australia
| | - Daniel J Scott
- The Florey, The University of Melbourne, Parkville, Victoria 3052, Australia; Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - David K Chalmers
- Faculty of Pharmacy and Pharmaceutical Sciences, Monash Institute of Pharmaceutical Sciences, Victoria 3052, Australia
| | - Ross A D Bathgate
- The Florey, The University of Melbourne, Parkville, Victoria 3052, Australia; Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Mohammed Akhter Hossain
- The Florey, The University of Melbourne, Parkville, Victoria 3052, Australia; School of Chemistry, The University of Melbourne, Parkville, Victoria 3052, Australia.
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3
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Wu H, Hoare BL, Handley TNG, Akhter Hossain M, Bathgate RAD. Development of a synthetic relaxin-3/INSL5 chimeric peptide ligand for NanoBiT complementation binding assays. Biochem Pharmacol 2024; 224:116238. [PMID: 38677442 DOI: 10.1016/j.bcp.2024.116238] [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: 01/16/2024] [Revised: 04/09/2024] [Accepted: 04/25/2024] [Indexed: 04/29/2024]
Abstract
INSL5 and relaxin-3 are relaxin family peptides with important roles in gut and brain function, respectively. They mediate their actions through the class A GPCRs RXFP4 and RXFP3. RXFP4 has been proposed to be a therapeutic target for colon motility disorders whereas RXFP3 targeting could be effective for neurological conditions such as anxiety. Validation of these targets has been limited by the lack of specific ligands and the availability of robust ligand-binding assays for their development. In this study, we have utilized NanoBiT complementation to develop a SmBiT-conjugated tracer for use with LgBiT-fused RXFP3 and RXFP4. The low affinity between LgBiT:SmBiT should result in a low non-specific luminescence signal and enable the quantification of binding without the tedious separation of non-bound ligands. We used solid-phase peptide synthesis to produce a SmBiT-labelled RXFP3/4 agonist, R3/I5, where SmBiT was conjugated to the B-chain N-terminus via a PEG12 linker. Both SmBiT-R3/I5 and R3/I5 were synthesized and purified in high purity and yield. Stable HEK293T cell lines expressing LgBiT-RXFP3 and LgBiT-RXFP4 were produced and demonstrated normal signaling in response to the synthetic R3/I5 peptide. Binding was first characterized in whole-cell binding kinetic assays validating that the SmBiT-R3/I5 bound to both cell lines with nanomolar affinity with minimal non-specific binding without bound and free SmBiT-R3/I5 separation. We then optimized membrane binding assays, demonstrating easy and robust analysis of both saturation and competition binding from frozen membranes. These assays therefore provide an appropriate rigorous binding assay for the high-throughput analysis of RXFP3 and RXFP4 ligands.
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Affiliation(s)
- Hongkang Wu
- The Florey, University of Melbourne, Victoria, Australia
| | | | | | - Mohammed Akhter Hossain
- The Florey, University of Melbourne, Victoria, Australia; School of Chemistry, University of Melbourne, Victoria, Australia; Department of Biochemistry and Pharmacology, University of Melbourne, Victoria, Australia.
| | - Ross A D Bathgate
- The Florey, University of Melbourne, Victoria, Australia; Department of Biochemistry and Pharmacology, University of Melbourne, Victoria, Australia.
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4
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Hossain MA, Praveen P, Noorzi NA, Wu H, Harrison IP, Handley T, Selemidis S, Samuel CS, Bathgate RAD. Development of Novel High-Affinity Antagonists for the Relaxin Family Peptide Receptor 1. ACS Pharmacol Transl Sci 2023; 6:842-853. [PMID: 37200817 PMCID: PMC10186362 DOI: 10.1021/acsptsci.3c00053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Indexed: 05/20/2023]
Abstract
H2 relaxin is a peptide hormone that exerts its biological actions through the G protein-coupled receptor, RXFP1. The numerous important biological functions of H2 relaxin, including potent renal, vasodilatory, cardioprotective, and anti-fibrotic actions, have resulted in considerable interest in its use as a therapeutic for various cardiovascular diseases and other fibrotic indications. Interestingly though, H2 relaxin and RXFP1 have been shown to be overexpressed in prostate cancer, allowing for the downregulation or blocking of relaxin/RXFP1 to decrease prostate tumor growth. These findings suggest the application of an RXFP1 antagonist for the treatment of prostate cancer. However, these therapeutically relevant actions are still poorly understood and have been hindered by the lack of a high-affinity antagonist. In this study, we chemically synthesized three novel H2 relaxin analogues that have complex insulin-like structures with two chains (A and B) and three disulfide bridges. We report here the structure-activity relationship studies on H2 relaxin that resulted in the development of a novel high-affinity RXFP1 antagonist, H2 B-R13HR (∼40 nM), that has only one extra methylene group in the side chain of arginine 13 in the B-chain (ArgB13) of H2 relaxin. Most notably, the synthetic peptide was shown to be active in a mouse model of prostate tumor growth in vivo where it inhibited relaxin-mediated tumor growth. Our compound H2 B-R13HR will be an important research tool to understand relaxin actions through RXFP1 and may be a potential lead compound for the treatment of prostate cancer.
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Affiliation(s)
- Mohammed Akhter Hossain
- Florey
Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3010, Victoria, Australia
- School
of Chemistry, University of Melbourne, Parkville 3010, Victoria, Australia
- Department
of Biochemistry and Pharmacology, University
of Melbourne, Parkville 3010, Victoria, Australia
| | - Praveen Praveen
- Florey
Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3010, Victoria, Australia
| | - Nurhayati Ahmad Noorzi
- Cardiovascular
Disease Program, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
- Department
of Pharmacology, Monash University, Clayton 3800, Victoria, Australia
| | - Hongkang Wu
- Florey
Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3010, Victoria, Australia
- Department
of Biochemistry and Pharmacology, University
of Melbourne, Parkville 3010, Victoria, Australia
| | - Ian P. Harrison
- Cardiovascular
Disease Program, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
- Department
of Pharmacology, Monash University, Clayton 3800, Victoria, Australia
| | - Thomas Handley
- Florey
Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3010, Victoria, Australia
| | - Stavros Selemidis
- School
of
Health and Biomedical Sciences, RMIT University, Bundoora 3083, Victoria, Australia
| | - Chrishan S. Samuel
- Cardiovascular
Disease Program, Monash Biomedicine Discovery Institute, Monash University, Clayton 3800, Victoria, Australia
- Department
of Pharmacology, Monash University, Clayton 3800, Victoria, Australia
| | - Ross A. D. Bathgate
- Florey
Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3010, Victoria, Australia
- Department
of Biochemistry and Pharmacology, University
of Melbourne, Parkville 3010, Victoria, Australia
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5
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Liu M, Li Q, Delaine C, Wu H, Arsenakis Y, White BF, Forbes BE, Chandrashekar C, Hossain MA. Total Chemical Synthesis of Palmitoyl-Conjugated Insulin. ACS OMEGA 2023; 8:13715-13720. [PMID: 37091377 PMCID: PMC10116525 DOI: 10.1021/acsomega.2c07918] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 03/27/2023] [Indexed: 05/03/2023]
Abstract
Commercially available insulins are manufactured by recombinant methods for the treatment of diabetes. Long-acting insulin drugs (e.g., detemir and degludec) are obtained by fatty acid conjugation at LysB29 ε-amine of insulin via acid-amide coupling. There are three amine groups in insulin, and they all react with fatty acids in alkaline conditions. Due to the lack of selectivity, such conjugation reactions produce non-desired byproducts. We designed and chemically synthesized a novel thiol-insulin scaffold (CysB29-insulin II), by replacing the LysB29 residue in insulin with the CysB29 residue. Then, we conjugated a fatty acid moiety (palmitic acid, C16) to CysB29-insulin II by a highly efficient and selective thiol-maleimide conjugation reaction. We obtained the target peptide (palmitoyl-insulin) rapidly within 5 min without significant byproducts. The palmitoyl-insulin is shown to be structurally similar to insulin and biologically active both in vitro and in vivo. Importantly, unlike native insulin, palmitoyl-insulin is slow and long-acting.
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Affiliation(s)
- Mengjie Liu
- Monash
Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia
- The
Florey Institute of Neuroscience and Mental Health, Parkville 3052, Australia
| | - Qingyang Li
- The
Florey Institute of Neuroscience and Mental Health, Parkville 3052, Australia
- Sinochem
Pharmaceutical Co., Ltd, 21 Floor Jincheng building, Longpanzhong road, 216, Nanjing 210002, China
| | - Carlie Delaine
- Discipline
of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Adelaide, South Australia 5042, Australia
| | - Hongkang Wu
- The
Florey Institute of Neuroscience and Mental Health, Parkville 3052, Australia
| | - Yanni Arsenakis
- Department
of Medicine (Austin Health), The University
of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Barbara F. White
- Department
of Medicine (Austin Health), The University
of Melbourne, Heidelberg, Victoria 3084, Australia
| | - Briony E. Forbes
- Discipline
of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Adelaide, South Australia 5042, Australia
| | | | - Mohammed Akhter Hossain
- The
Florey Institute of Neuroscience and Mental Health, Parkville 3052, Australia
- School of
Chemistry, and Department of Biochemistry and Pharmacology, The University of Melbourne, Victoria 3010, Australia
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6
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Woodward ORM, Gribble FM, Reimann F, Lewis JE. Gut peptide regulation of food intake - evidence for the modulation of hedonic feeding. J Physiol 2022; 600:1053-1078. [PMID: 34152020 DOI: 10.1113/jp280581] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 05/17/2021] [Indexed: 12/13/2022] Open
Abstract
The number of people living with obesity has tripled worldwide since 1975 with serious implications for public health, as obesity is linked to a significantly higher chance of early death from associated comorbidities (metabolic syndrome, type 2 diabetes, cardiovascular disease and cancer). As obesity is a consequence of food intake exceeding the demands of energy expenditure, efforts are being made to better understand the homeostatic and hedonic mechanisms governing food intake. Gastrointestinal peptides are secreted from enteroendocrine cells in response to nutrient and energy intake, and modulate food intake either via afferent nerves, including the vagus nerve, or directly within the central nervous system, predominantly gaining access at circumventricular organs. Enteroendocrine hormones modulate homeostatic control centres at hypothalamic nuclei and the dorso-vagal complex. Additional roles of these peptides in modulating hedonic food intake and/or preference via the neural systems of reward are starting to be elucidated, with both peripheral and central peptide sources potentially contributing to central receptor activation. Pharmacological interventions and gastric bypass surgery for the treatment of type 2 diabetes and obesity elevate enteroendocrine hormone levels and also alter food preference. Hence, understanding of the hedonic mechanisms mediated by gut peptide action could advance development of potential therapeutic strategies for the treatment of obesity and its comorbidities.
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Affiliation(s)
- Orla R M Woodward
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - Fiona M Gribble
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - Frank Reimann
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
| | - Jo E Lewis
- Wellcome Trust - MRC Institute of Metabolic Science Metabolic Research Laboratories, Addenbrooke's Hospital, Hills Road, Cambridge, CB2 0QQ, UK
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7
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Liu M, White BF, Praveen P, Li W, Lin F, Wu H, Li R, Delaine C, Forbes BE, Wade JD, Hossain MA. Engineering of a Biologically Active Insulin Dimer. J Med Chem 2021; 64:17448-17454. [PMID: 34797669 DOI: 10.1021/acs.jmedchem.1c01594] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The growing epidemic of diabetes means that there is a need for therapies that are more efficacious, safe, and convenient. Here, we report the efficient synthesis of a novel disulfide dimer of human insulin tethered at the N-terminus of its B-chain through placement of a cysteine residue. The resulting peptide was shown to bind to both the insulin receptor isoform B and insulin-like growth factor-1 receptor with comparable affinity to native insulin. In in vivo insulin tolerance tests, the dimer was equipotent to Actrapid insulin and possessed a sustained duration of action greater than that of Actrapid and Glargine. While the secondary structure of our dimeric insulin was similar to that of insulin, it was more resistant to proteolysis. More importantly, our analogue was produced in quantitative yield from a monomeric thiol insulin scaffold. Our results suggest that this dimer has significant potential to address the clinical needs in the treatment of diabetes.
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Affiliation(s)
- Mengjie Liu
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Barbara F White
- Department of Medicine (Austin Health), The University of Melbourne, Victoria 3010, Australia
| | - Praveen Praveen
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Wenyi Li
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Feng Lin
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Hongkang Wu
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Rong Li
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia
| | - Carlie Delaine
- Discipline of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Bedford Park, South Australia 5042, Australia
| | - Briony E Forbes
- Discipline of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Bedford Park, South Australia 5042, Australia
| | - John D Wade
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.,The Florey Department of Neuroscience and Mental Health, The University Melbourne, Victoria 3010, Australia.,School of Chemistry, The University of Melbourne, Victoria 3010, Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Victoria 3010, Australia.,The Florey Department of Neuroscience and Mental Health, The University Melbourne, Victoria 3010, Australia.,School of Chemistry, The University of Melbourne, Victoria 3010, Australia
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8
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Structural Insights into the Unique Modes of Relaxin-Binding and Tethered-Agonist Mediated Activation of RXFP1 and RXFP2. J Mol Biol 2021; 433:167217. [PMID: 34454945 DOI: 10.1016/j.jmb.2021.167217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/09/2021] [Accepted: 08/19/2021] [Indexed: 01/01/2023]
Abstract
Our poor understanding of the mechanism by which the peptide-hormone H2 relaxin activates its G protein coupled receptor, RXFP1 and the related receptor RXFP2, has hindered progress in its therapeutic development. Both receptors possess large ectodomains, which bind H2 relaxin, and contain an N-terminal LDLa module that is essential for receptor signaling and postulated to be a tethered agonist. Here, we show that a conserved motif (GDxxGWxxxF), C-terminal to the LDLa module, is critical for receptor activity. Importantly, this motif adopts different structures in RXFP1 and RXFP2, suggesting distinct activation mechanisms. For RXFP1, the motif is flexible, weakly associates with the LDLa module, and requires H2 relaxin binding to stabilize an active conformation. Conversely, the GDxxGWxxxF motif in RXFP2 is more closely associated with the LDLa module, forming an essential binding interface for H2 relaxin. These differences in the activation mechanism will aid drug development targeting these receptors.
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9
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Pustovit RV, Zhang X, Liew JJ, Praveen P, Liu M, Koo A, Oparija-Rogenmozere L, Ou Q, Kocan M, Nie S, Bathgate RA, Furness JB, Hossain MA. A Novel Antagonist Peptide Reveals a Physiological Role of Insulin-Like Peptide 5 in Control of Colorectal Function. ACS Pharmacol Transl Sci 2021; 4:1665-1674. [PMID: 34661082 DOI: 10.1021/acsptsci.1c00171] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Indexed: 12/23/2022]
Abstract
Insulin-like peptide 5 (INSL5), the natural ligand for the relaxin family peptide receptor 4 (RXFP4), is a gut hormone that is exclusively produced by colonic L-cells. We have recently developed an analogue of INSL5, INSL5-A13, that acts as an RXFP4 agonist in vitro and stimulates colorectal propulsion in wild-type mice but not in RXFP4-knockout mice. These results suggest that INSL5 may have a physiological role in the control of colorectal motility. To investigate this possibility, in this study we designed and developed a novel INSL5 analogue, INSL5-A13NR. This compound is a potent antagonist, without significant agonist activity, in two in vitro assays. We report here for the first time that this novel antagonist peptide blocks agonist-induced increase in colon motility in mice that express RXFP4. Our data also show that colorectal propulsion induced by intracolonic administration of bacterial products (short-chain fatty acids, SCFAs) is antagonized by INSL5-A13NR. Therefore, INSL5-A13NR is an important research tool and potential drug lead for the treatment of colon motility disorders, such as bacterial diarrheas.
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Affiliation(s)
- Ruslan V Pustovit
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Xiaozhou Zhang
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Jamie Jm Liew
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Praveen Praveen
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Mengjie Liu
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Ada Koo
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Lalita Oparija-Rogenmozere
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Qinghao Ou
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Martina Kocan
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Shuai Nie
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Ross Ad Bathgate
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - John B Furness
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health; Department of Anatomy and Physiology; School of Biosciences, Melbourne Mass Spectrometry and Proteomics Facility, Bio21 Institute; Department of Biochemistry and Pharmacology; School of Chemistry; The University of Melbourne, Parkville, Victoria 3052, Australia
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10
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Abstract
The pancreatic peptide hormone insulin, first discovered exactly 100 years ago, is essential for glycemic control and is used as a therapeutic for the treatment of type 1 and, increasingly, type 2 diabetes. With a worsening global diabetes epidemic and its significant health budget imposition, there is a great demand for new analogues possessing improved physical and functional properties. However, the chemical synthesis of insulin's intricate 51-amino acid, two-chain, three-disulfide bond structure, together with the poor physicochemical properties of both the individual chains and the hormone itself, has long represented a major challenge to organic chemists. This review provides a timely overview of the past efforts to chemically assemble this fascinating hormone using an array of strategies to enable both correct folding of the two chains and selective formation of disulfide bonds. These methods not only have contributed to general peptide synthesis chemistry and enabled access to the greatly growing numbers of insulin-like and cystine-rich peptides but also, today, enable the production of insulin at the synthetic efficiency levels of recombinant DNA expression methods. They have led to the production of a myriad of novel analogues with optimized structural and functional features and of the feasibility for their industrial manufacture.
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11
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Zhang X, Bathgate RAD, Hossain MA. Human Insulin-like Peptide 5 (INSL5). Identification of a Simplified Version of Two-Chain Analog A13. ACS Med Chem Lett 2020; 11:2455-2460. [PMID: 33335667 DOI: 10.1021/acsmedchemlett.0c00435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Accepted: 10/08/2020] [Indexed: 01/14/2023] Open
Abstract
The receptor for insulin-like peptide 5 (INSL5), RXFP4, is a potential pharma target for treating human conditions such as constipation, anorexia, and obesity. However, since INSL5 has a complex structure of two chains and three disulfide bonds, its synthesis has proven to be extremely difficult via either chemical or recombinant approaches. Previous studies led to the engineering of a high yielding simplified INSL5 analog, named analog 13 (A13), which retains native INSL5-like activity. The focus of this study is to further simplify the structure of A13 by truncating the N-terminal residues of the B-chain. We have found that the first six residues at the N-terminus of A13 are not important for RXFP4 binding and cAMP potency. The most minimized active structure of INSL5 identified in this study is A13: B7-24 which will be an important research tool to study the physiological role of RXFP4 and a template for further modification to improve its pharmacokinetic properties.
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12
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Lin GY, Lin L, Cai XQ, Dai AT, Zhu Y, Li J, Liu Q, Yang DH, Bathgate RAD, Wang MW. High-throughput screening campaign identifies a small molecule agonist of the relaxin family peptide receptor 4. Acta Pharmacol Sin 2020; 41:1328-1336. [PMID: 32235863 PMCID: PMC7608467 DOI: 10.1038/s41401-020-0390-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 02/21/2020] [Indexed: 01/07/2023] Open
Abstract
Relaxin/insulin-like family peptide receptor 4 (RXFP4) is a class A G protein-coupled receptor (GPCR), and insulin-like peptide 5 (INSL5) is its endogenous ligand. Although the precise physiological role of INSL5/RXFP4 remains elusive, a number of studies have suggested it to be a potential therapeutic target for obesity and other metabolic disorders. Since selective agonists of RXFP4 are scarcely available and peptidic analogs of INSL5 are hard to make, we conducted a high-throughput screening campaign against 52,000 synthetic and natural compounds targeting RXFP4. Of the 109 initial hits discovered, only 3 compounds were confirmed in secondary screening, with JK0621-D008 displaying the best agonism at human RXFP4. Its S-configuration stereoisomer (JK1) was subsequently isolated and validated by a series of bioassays, demonstrating a consistent agonistic effect in cells overexpressing RXFP4. This scaffold may provide a valuable tool to further explore the biological functions of RXFP4.
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13
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Li SB, Liu YY, Yuan L, Ji MF, Zhang A, Li HY, Tang LQ, Fang SG, Zhang H, Xing S, Li MZ, Zhong Q, Lin SJ, Liu WL, Huang P, Zeng YX, Zheng YM, Ling ZQ, Sui JH, Zeng MS. Autocrine INSL5 promotes tumor progression and glycolysis via activation of STAT5 signaling. EMBO Mol Med 2020; 12:e12050. [PMID: 32657028 PMCID: PMC7507000 DOI: 10.15252/emmm.202012050] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 06/15/2020] [Accepted: 06/18/2020] [Indexed: 12/12/2022] Open
Abstract
Metabolic reprogramming plays important roles in development and progression of nasopharyngeal carcinoma (NPC), but the underlying mechanism has not been completely defined. In this work, we found INSL5 was elevated in NPC tumor tissue and the plasma of NPC patients. Plasma INSL5 could serve as a novel diagnostic marker for NPC, especially for serum VCA-IgA-negative patients. Moreover, higher plasma INSL5 level was associated with poor disease outcome. Functionally, INSL5 overexpression increased, whereas knockdown of its receptor GPCR142 or inhibition of INSL5 reduced cell proliferation, colony formation, and cell invasion in vitro and tumorigenicity in vivo. Mechanistically, INSL5 enhanced phosphorylation and nuclear translocation of STAT5 and promoted glycolytic gene expression, leading to induced glycolysis in cancer cells. Pharmaceutical inhibition of glycolysis by 2-DG or blockade of INSL5 by a neutralizing antibody reversed INSL5-induced proliferation and invasion, indicating that INSL5 can be a potential therapeutic target in NPC. In conclusion, INSL5 enhances NPC progression by regulating cancer cell metabolic reprogramming and is a potential diagnostic and prognostic marker as well as a therapeutic target for NPC.
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Affiliation(s)
- Shi-Bing Li
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Yan-Yan Liu
- Department of Nephrology, Division of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Li Yuan
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Ming-Fang Ji
- Cancer Research Institute of Zhongshan City, Zhongshan, China
| | - Ao Zhang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Hui-Yu Li
- National Institute of Biological Sciences, Beijing, China
| | - Lin-Quan Tang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Shuo-Gui Fang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China.,Department of Radiation Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Hua Zhang
- School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Shan Xing
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Man-Zhi Li
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Qian Zhong
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Shao-Jun Lin
- Department of Radiation Oncology, Fujian Provincial Cancer Hospital, Fuzhou, China
| | - Wan-Li Liu
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Peng Huang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Yi-Xin Zeng
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
| | - Yu-Ming Zheng
- Department of Clinical Laboratory, Wuzhou Red Cross Hospital, Wuzhou, China
| | | | - Jian-Hua Sui
- National Institute of Biological Sciences, Beijing, China
| | - Mu-Sheng Zeng
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, China
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14
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Diwakarla S, Bathgate RAD, Zhang X, Hossain MA, Furness JB. Colokinetic effect of an insulin-like peptide 5-related agonist of the RXFP4 receptor. Neurogastroenterol Motil 2020; 32:e13796. [PMID: 31989750 DOI: 10.1111/nmo.13796] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/04/2019] [Accepted: 12/20/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND Insulin-like peptide 5 (INSL5) is a hormone stored in colonic enteroendocrine cells that also contain the unrelated hormones, GLP-1 and PYY. It acts at the relaxin family peptide 4, RXFP4, receptor. RXFP4 is expressed by enteric neurons in the colon, and it has been speculated that INSL5, through its action on enteric neurons, might be involved in the control of colonic contractions. Similar to insulin and relaxin, INSL5 consists of A and B peptide chains linked by three disulfide bonds, two between the chains and one intrinsic to the A chain. Because of its complex structure, it is difficult to synthesize and to prepare peptide analogues to investigate its roles. We have recently developed a potent simplified peptide analogue, INSL5-A13 (INSL5 analogue 13). METHODS In the present work, we have investigated the actions of INSL5-A13 in mice. We investigated the ability of INSL5-A13 to increase the speed of emptying of a bead from the colon, after expulsion had been slowed by the peripherally restricted opioid agonist, loperamide (1 mg/kg). KEY RESULTS INSL5-A13 was a full agonist at the mouse RXFP4 expressed in HEK cells, with an EC50 of ~9 nmol/L. INSL5-A13 caused an acceleration of colorectal bead propulsion in mice constipated by loperamide in the dose range 0.2 to 60 µg/kg, with an EC50 of ~6 µg/kg in vivo. It also accelerated bead propulsion in untreated mice. Bead expulsion was not accelerated in RXFP4-/- mice. CONCLUSION AND INFERENCES Our data suggest that RXFP4 agonists could be useful in the treatment of constipation.
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Affiliation(s)
- Shanti Diwakarla
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Vic., Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Vic., Australia
| | - Ross A D Bathgate
- 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
| | - Xiaozhou Zhang
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Vic., Australia
| | - Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Vic., Australia.,School of Chemistry, University of Melbourne, Parkville, Vic., Australia
| | - John B Furness
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, Vic., Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Vic., Australia
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15
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Hossain MA, Okamoto R, Karas JA, Praveen P, Liu M, Forbes BE, Wade JD, Kajihara Y. Total Chemical Synthesis of a Nonfibrillating Human Glycoinsulin. J Am Chem Soc 2019; 142:1164-1169. [DOI: 10.1021/jacs.9b11424] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
| | - Ryo Okamoto
- Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 Japan
| | | | | | | | - Briony E. Forbes
- Discipline of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Bedford Park, South Australia 5042, Australia
| | | | - Yasuhiro Kajihara
- Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 Japan
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16
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Engineering of chimeric peptides as antagonists for the G protein-coupled receptor, RXFP4. Sci Rep 2019; 9:17828. [PMID: 31780677 PMCID: PMC6882824 DOI: 10.1038/s41598-019-53707-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 11/05/2019] [Indexed: 11/20/2022] Open
Abstract
Insulin-like peptide 5 (INSL5) is a very important pharma target for treating human conditions such as anorexia and diabetes. However, INSL5 with two chains and three disulfide bridges is an extremely difficult peptide to assemble by chemical or recombinant means. In a recent study, we were able to engineer a simplified INSL5 analogue 13 which is a relaxin family peptide receptor 4 (RXFP4)-specific agonist. To date, however, no RXFP4-specific antagonist (peptide or small molecule) has been reported in the literature. The focus of this study was to utilize the non-specific RXFP3/RXFP4 antagonist ΔR3/I5 as a template to rationally design an RXFP4 specific antagonist. Unexpectedly, we demonstrated that ΔR3/I5 exhibited partial agonism at RXFP4 when expressed in CHO cells which is associated with only partial antagonism of INSL5 analogue activation. In an attempt to improve RXFP4 specificity and antagonist activity we designed and chemically synthesized a series of analogues of ΔR3/I5. While all the chimeric analogues still demonstrated partial agonism at RXFP4, one peptide (Analogue 17) exhibited significantly improved RXFP4 specificity. Importantly, analogue 17 has a simplified structure which is more amenable to chemical synthesis. Therefore, analogue 17 is an ideal template for further development into a specific high affinity RXFP4 antagonist which will be an important tool to probe the physiological role of RXFP4/INSL5 axis.
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17
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Zaykov AN, Gelfanov VM, Perez-Tilve D, Finan B, DiMarchi RD. Insulin-like peptide 5 fails to improve metabolism or body weight in obese mice. Peptides 2019; 120:170116. [PMID: 31348991 DOI: 10.1016/j.peptides.2019.170116] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 06/29/2019] [Indexed: 12/26/2022]
Abstract
Insulin-like peptide 5 (INSL5) is a member of the insulin-like family of peptides. It has been reported to be orexigenic in rodent models of obesity with impaired glucose metabolism. We attempted to confirm this property as a first step in establishing the ability of INSL5 to successfully integrate with other agents more proven in their ability to reverse obesity and improve metabolism. INSL5 was chemically synthesized by two alternative methods to a native form and one that was site-specifically conjugated to a 20 KDa polyethylene glycol (PEG) polymer. The pharmacology of each peptide was assessed by high-dose chronic administration in normal and obese mice. INSL5 failed to produce pharmacologically relevant effects on food intake, body weight or glucose control indicative of a negligible role of the peptide in the control of feeding and glucose metabolism.
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Affiliation(s)
| | | | - Diego Perez-Tilve
- Department of Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Brian Finan
- Novo Nordisk Research Center, Indianapolis, IN, 46241, USA
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18
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Patil NA, Karas JA, Wade JD, Hossain MA, Tailhades J. Rapid Photolysis‐Mediated Folding of Disulfide‐Rich Peptides. Chemistry 2019; 25:8599-8603. [DOI: 10.1002/chem.201901334] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Nitin A. Patil
- The Monash Biomedicine Discovery Institute 15 Innovation Walk Clayton VIC 3800 Australia
| | - John A. Karas
- Department of Pharmacology and TherapeuticsThe University of Melbourne Victoria 3010 Australia
| | - John D. Wade
- Department of Pharmacology and TherapeuticsThe University of Melbourne Victoria 3010 Australia
- The Florey Institute of Neuroscience and Mental HealthUniversity of Melbourne 30 Royal Parade, Parkville Victoria 3052 Australia
| | - Mohammed Akhter Hossain
- Department of Pharmacology and TherapeuticsThe University of Melbourne Victoria 3010 Australia
- The Florey Institute of Neuroscience and Mental HealthUniversity of Melbourne 30 Royal Parade, Parkville Victoria 3052 Australia
| | - Julien Tailhades
- The Monash Biomedicine Discovery Institute 15 Innovation Walk Clayton VIC 3800 Australia
- EMBL AustraliaMonash University Clayton Victoria 3800 Australia
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19
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DeChristopher B, Park SH, Vong L, Bamford D, Cho HH, Duvadie R, Fedolak A, Hogan C, Honda T, Pandey P, Rozhitskaya O, Su L, Tomlinson E, Wallace I. Discovery of a small molecule RXFP3/4 agonist that increases food intake in rats upon acute central administration. Bioorg Med Chem Lett 2019; 29:991-994. [PMID: 30824200 DOI: 10.1016/j.bmcl.2019.02.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 01/04/2019] [Accepted: 02/10/2019] [Indexed: 01/07/2023]
Abstract
The relaxin family peptide receptors have been implicated in numerous physiological processes including energy homeostasis, cardiac function, wound healing, and reproductive function. Two family members, RXFP3 and RXFP4, are class A GPCRs with endogenous peptide ligands (relaxin-3 and insulin-like peptide 5 (INSL5), respectively). Polymorphisms in relaxin-3 and RXFP3 have been associated with obesity, diabetes, and hypercholesterolemia. Moreover, central administration of relaxin-3 in rats has been shown to increase food intake, leading to body weight gain. Reported RXFP3 and RXFP4 ligands have been restricted to peptides (both endogenous and synthetic) as well as a low molecular weight positive allosteric modulator requiring a non-endogenous orthosteric ligand. Described here is the discovery of the first potent low molecular weight dual agonists of RXFP3/4. The scaffold identified is competitive with a chimeric relaxin-3/INSL5 peptide for RXFP3 binding, elicits similar downstream signaling as relaxin-3, and increases food intake in rats following acute central administration. This is the first report of small molecule RXFP3/4 agonism.
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Affiliation(s)
- Brian DeChristopher
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States.
| | - Soo-Hee Park
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Linh Vong
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Derek Bamford
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Hyun-Hee Cho
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Rohit Duvadie
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Allison Fedolak
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Christopher Hogan
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Toshiyuki Honda
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Pramod Pandey
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Olga Rozhitskaya
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Liansheng Su
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Elizabeth Tomlinson
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
| | - Iain Wallace
- Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, United States
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20
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Valkovic AL, Leckey MB, Whitehead AR, Hossain MA, Inoue A, Kocan M, Bathgate RAD. Real-time examination of cAMP activity at relaxin family peptide receptors using a BRET-based biosensor. Pharmacol Res Perspect 2018; 6:e00432. [PMID: 30263124 PMCID: PMC6153321 DOI: 10.1002/prp2.432] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 08/29/2018] [Indexed: 12/11/2022] Open
Abstract
Relaxin family peptide (RXFPs) 1-4 receptors modulate the activity of cyclic adenosine monophosphate (cAMP) to produce a range of physiological functions. RXFP1 and RXFP2 increase cAMP via Gαs, whereas RXFP3 and RXFP4 inhibit cAMP via Gαi/o. RXFP1 also shows a delayed increase in cAMP downstream of Gαi3. In this study we have assessed whether the bioluminescence resonance energy transfer (BRET)-based biosensor CAMYEL (cAMP sensor using YFP-Epac-Rluc), which allows real-time measurement of cAMP activity in live cells, will aid in understanding ligand- and cell-specific RXFP signaling. CAMYEL detected concentration-dependent changes in cAMP activity at RXFP1-4 in recombinant cell lines, using a variety of ligands with potencies comparable to those seen in conventional cAMP assays. We used RXFP2 and RXFP3 antagonists to demonstrate that CAMYEL detects dynamic changes in cAMP by reversing cAMP activation or inhibition respectively, with real-time addition of antagonist after agonist stimulation. To demonstrate the utility of CAMYEL to detect cAMP activation in native cells expressing low levels of RXFP receptor, we cloned CAMYEL into a lentiviral vector and transduced THP-1 cells, which express low levels of RXFP1. THP-1 CAMYEL cells demonstrated robust cAMP activation in response to relaxin. However, the CAMYEL assay was unable to detect the Gαi3-mediated phase of RXFP1 cAMP activation in PTX-treated THP-1 cells or HEK293A cells with knockout of Gαs. Our data demonstrate that cytoplasmically-expressed CAMYEL efficiently detects real-time cAMP activation by Gαs or inhibition by Gαi/o but may not detect cAMP generated in specific intracellular compartments such as that generated by Gαi3 upon RXFP1 activation.
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Affiliation(s)
- Adam L. Valkovic
- Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVictoriaAustralia
| | - Miranda B. Leckey
- Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVictoriaAustralia
| | - Alice R. Whitehead
- Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVictoriaAustralia
| | - Mohammed A. Hossain
- Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVictoriaAustralia
| | - Asuka Inoue
- Graduate School of Pharmaceutical SciencesTohoku UniversityAobaMiyagiJapan
| | - Martina Kocan
- Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVictoriaAustralia
| | - Ross A. D. Bathgate
- Florey Institute of Neuroscience and Mental HealthThe University of MelbourneParkvilleVictoriaAustralia
- Department of Biochemistry and Molecular BiologyThe University of MelbourneParkvilleVictoriaAustralia
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21
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Zaykov AN, Gelfanov VM, Liu F, DiMarchi RD. High-Yield Synthesis of Human Insulin-Like Peptide 5 Employing a Nonconventional Strategy. Org Lett 2018; 20:3695-3699. [DOI: 10.1021/acs.orglett.8b01501] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Alexander N. Zaykov
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Vasily M. Gelfanov
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Fa Liu
- Novo Nordisk Research Center, Seattle, Washington 98109, United States
| | - Richard D. DiMarchi
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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22
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Zaykov AN, Gelfanov VM, Liu F, DiMarchi RD. Synthesis and Characterization of the R27S Genetic Variant of Insulin-like Peptide 5. ChemMedChem 2018; 13:852-859. [DOI: 10.1002/cmdc.201800057] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 02/20/2018] [Indexed: 12/16/2022]
Affiliation(s)
- Alexander N. Zaykov
- Novo Nordisk Research Center Indianapolis; 5225 Exploration Drive Indianapolis IN 46241 USA
| | - Vasily M. Gelfanov
- Novo Nordisk Research Center Indianapolis; 5225 Exploration Drive Indianapolis IN 46241 USA
| | - Fa Liu
- Novo Nordisk Research Center Seattle; 530 Fairview Avenue N. #5000 Seattle WA 98109 USA
| | - Richard D. DiMarchi
- Novo Nordisk Research Center Indianapolis; 5225 Exploration Drive Indianapolis IN 46241 USA
- Department of Chemistry; Indiana University; 800 E. Kirkwood Avenue Bloomington IN 47405 USA
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23
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Kay R, Galvin S, Larraufie P, Reimann F, Gribble F. Liquid chromatography/mass spectrometry based detection and semi-quantitative analysis of INSL5 in human and murine tissues. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:1963-1973. [PMID: 28857318 PMCID: PMC5698736 DOI: 10.1002/rcm.7978] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/23/2017] [Accepted: 08/27/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Insulin-like peptide 5 (INSL5) is a hormone produced by enteroendocrine L-cells in the colon that has recently been implicated in the control of metabolic homeostasis. However, research into its physiology has been hindered by the reported unreliability of commercially available immunoassays and additional detection assays would benefit this emerging field. METHODS Peptides from purified murine L-cells and homogenates from both human and mouse colonic tissues were extracted by precipitating larger proteins with acetonitrile. Untargeted liquid chromatography/tandem mass spectrometry (LC/MS/MS) analyses, followed by database searching, were used to detect and identify various INSL5 gene derived peptides and characterise their precise sequence. A similar approach was developed to quantify INSL5 levels in primary intestinal culture supernatants after purification and concentration by solid-phase extraction. RESULTS Mass spectral analysis of purified enteroendocrine cells and tissue homogenates identified the exact sequence of A and B chains of INSL5 endogenously expressed in L-cells. Differences in the endogenously processed peptide and the Swissprot database entry were observed for murine INSL5, whereas the human sequence matched previous predictions from heterologous expression experiments. INSL5 was detected in the supernatant of human and mouse primary colonic cultures and concentrations increased after treatment with a known L-cell stimulus. CONCLUSIONS The first LC/MS/MS-based method capable of the detection and semi-quantitative analysis of endogenous INSL5 using MS-based techniques has been demonstrated. The methodology will enable the identification of stimulants for INSL5 secretion from murine and human primary colonic epithelial cultures.
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Affiliation(s)
- R.G. Kay
- Metabolic Research LaboratoriesInstitute of Metabolic Science, Addenbrooke's HospitalHills RoadCambridgeCB2 0QQUK
| | - S. Galvin
- Metabolic Research LaboratoriesInstitute of Metabolic Science, Addenbrooke's HospitalHills RoadCambridgeCB2 0QQUK
| | - P. Larraufie
- Metabolic Research LaboratoriesInstitute of Metabolic Science, Addenbrooke's HospitalHills RoadCambridgeCB2 0QQUK
| | - F. Reimann
- Metabolic Research LaboratoriesInstitute of Metabolic Science, Addenbrooke's HospitalHills RoadCambridgeCB2 0QQUK
| | - F.M. Gribble
- Metabolic Research LaboratoriesInstitute of Metabolic Science, Addenbrooke's HospitalHills RoadCambridgeCB2 0QQUK
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24
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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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25
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Liu F, Li P, Gelfanov V, Mayer J, DiMarchi R. Synthetic Advances in Insulin-like Peptides Enable Novel Bioactivity. Acc Chem Res 2017; 50:1855-1865. [PMID: 28771323 DOI: 10.1021/acs.accounts.7b00227] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Insulin is a miraculous hormone that has served a seminal role in the treatment of insulin-dependent diabetes for nearly a century. Insulin resides within in a superfamily of structurally related peptides that are distinguished by three invariant disulfide bonds that anchor the three-dimensional conformation of the hormone. The additional family members include the insulin-like growth factors (IGF) and the relaxin-related set of peptides that includes the so-called insulin-like peptides. Advances in peptide chemistry and rDNA-based synthesis have enabled the preparation of multiple insulin analogues. The translation of these methods from insulin to related peptides has presented unique challenges that pertain to differing biophysical properties and unique amino acid compositions. This Account presents a historical context for the advances in the chemical synthesis of insulin and the related peptides, with division into two general categories where disulfide bond formation is facilitated by native conformational folding or alternatively orthogonal chemical reactivity. The inherent differences in biophysical properties of insulin-like peptides, and in particular within synthetic intermediates, have constituted a central limitation to achieving high yield synthesis of properly folded peptides. Various synthetic approaches have been advanced in the past decade to successfully address this challenge. The use of chemical ligation and metastable amide bond surrogates are two of the more important synthetic advances in the preparation of high quality synthetic precursors to high potency peptides. The discovery and application of biomimetic connecting peptides simplifies proper disulfide formation and the subsequent traceless removal by chemical methods dramatically simplifies the total synthesis of virtually any two-chain insulin-like peptide. We report the application of these higher synthetic yield methodologies to the preparation of insulin-like peptides in support of exploratory in vivo studies requiring a large quantity of peptide. Tangentially, we demonstrate the use of these methods to study the relative importance of the IGF-1 connecting peptide to its biological activity. We report the translation of these finding in search of an insulin analog that might be comparably enhanced by a suitable connecting peptide for interaction with the insulin receptor, as occurs with IGF-1 and its receptor. The results identify a unique receptor site in the IGF-1 receptor from which this enhancement derives. The selective substitution of this specific IGF-1 receptor sequence into the homologous site in the insulin receptor generated a chimeric receptor that was equally capable of signaling with insulin or IGF-1. This novel receptor proved to enhance the potency of lower affinity insulin ligands when they were supplemented with the IGF-1 connecting peptide that similarly enhanced IGF-1 activity at its receptor. The chimeric insulin receptor demonstrated no further enhancement of potency for native insulin when it was similarly prepared as a single-chain analogue with a native IGF-1 connecting peptide. These results suggest a more highly evolved insulin receptor structure where the requirement for an additional structural element to achieve high potency interaction as demonstrated for IGF-1 is no longer required.
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Affiliation(s)
- Fa Liu
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Pengyun Li
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Vasily Gelfanov
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - John Mayer
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
| | - Richard DiMarchi
- Novo Nordisk Research Center Indianapolis, Indianapolis, Indiana 46241, United States
- Department
of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
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26
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Littler DR, Ang SY, Moriel DG, Kocan M, Kleifeld O, Johnson MD, Tran MT, Paton AW, Paton JC, Summers RJ, Schembri MA, Rossjohn J, Beddoe T. Structure-function analyses of a pertussis-like toxin from pathogenic Escherichia coli reveal a distinct mechanism of inhibition of trimeric G-proteins. J Biol Chem 2017; 292:15143-15158. [PMID: 28663369 DOI: 10.1074/jbc.m117.796094] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 06/14/2017] [Indexed: 11/06/2022] Open
Abstract
Pertussis-like toxins are secreted by several bacterial pathogens during infection. They belong to the AB5 virulence factors, which bind to glycans on host cell membranes for internalization. Host cell recognition and internalization are mediated by toxin B subunits sharing a unique pentameric ring-like assembly. Although the role of pertussis toxin in whooping cough is well-established, pertussis-like toxins produced by other bacteria are less studied, and their mechanisms of action are unclear. Here, we report that some extra-intestinal Escherichia coli pathogens (i.e. those that reside in the gut but can spread to other bodily locations) encode a pertussis-like toxin that inhibits mammalian cell growth in vitro We found that this protein, EcPlt, is related to toxins produced by both nontyphoidal and typhoidal Salmonella serovars. Pertussis-like toxins are secreted as disulfide-bonded heterohexamers in which the catalytic ADP-ribosyltransferase subunit is activated when exposed to the reducing environment in mammalian cells. We found here that the reduced EcPlt exhibits large structural rearrangements associated with its activation. We noted that inhibitory residues tethered within the NAD+-binding site by an intramolecular disulfide in the oxidized state dissociate upon the reduction and enable loop restructuring to form the nucleotide-binding site. Surprisingly, although pertussis toxin targets a cysteine residue within the α subunit of inhibitory trimeric G-proteins, we observed that activated EcPlt toxin modifies a proximal lysine/asparagine residue instead. In conclusion, our results reveal the molecular mechanism underpinning activation of pertussis-like toxins, and we also identified differences in host target specificity.
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Affiliation(s)
- Dene R Littler
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Sheng Y Ang
- the Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Danilo G Moriel
- the School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Martina Kocan
- the Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Oded Kleifeld
- the Faculty of Biology, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - Matthew D Johnson
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Mai T Tran
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Adrienne W Paton
- the Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, South Australia 5005, Australia
| | - James C Paton
- the Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, South Australia 5005, Australia
| | - Roger J Summers
- the Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Mark A Schembri
- the School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jamie Rossjohn
- From the Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia, .,the Institute of Infection and Immunity, School of Medicine, Cardiff University, Heath Park, Cardiff CF14 4XN, Wales, United Kingdom.,the ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia, and
| | - Travis Beddoe
- the Department of Animal, Plant and Soil Science and Centre for AgriBioscience, La Trobe University, Bundoora, Victoria 3086, Australia
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27
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Thalluri K, Kou B, Yang X, Zaykov AN, Mayer JP, Gelfanov VM, Liu F, DiMarchi RD. Synthesis of relaxin‐2 and insulin‐like peptide 5 enabled by novel tethering and traceless chemical excision. J Pept Sci 2017; 23:455-465. [DOI: 10.1002/psc.3010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Revised: 04/04/2017] [Accepted: 04/05/2017] [Indexed: 01/15/2023]
Affiliation(s)
- Kishore Thalluri
- Department of ChemistryIndiana University Bloomington IN 47405 USA
| | - Binbin Kou
- Novo Nordisk Research Center Indianapolis 5225 Exploration Drive Indianapolis IN 46241 USA
| | - Xu Yang
- Department of ChemistryIndiana University Bloomington IN 47405 USA
| | - Alexander N. Zaykov
- Novo Nordisk Research Center Indianapolis 5225 Exploration Drive Indianapolis IN 46241 USA
| | - John P. Mayer
- Novo Nordisk Research Center Indianapolis 5225 Exploration Drive Indianapolis IN 46241 USA
| | - Vasily M. Gelfanov
- Novo Nordisk Research Center Indianapolis 5225 Exploration Drive Indianapolis IN 46241 USA
| | - Fa Liu
- Novo Nordisk Research Center Indianapolis 5225 Exploration Drive Indianapolis IN 46241 USA
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28
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Goyal B, Srivastava KR, Durani S. N-terminal diproline and charge group effects on the stabilization of helical conformation in alanine-based short peptides: CD studies with water and methanol as solvent. J Pept Sci 2017; 23:431-437. [PMID: 28425159 DOI: 10.1002/psc.3005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 03/17/2017] [Accepted: 03/20/2017] [Indexed: 12/25/2022]
Abstract
Protein folding problem remains a formidable challenge as main chain, side chain and solvent interactions remain entangled and have been difficult to resolve. Alanine-based short peptides are promising models to dissect protein folding initiation and propagation structurally as well as energetically. The effect of N-terminal diproline and charged side chains is assessed on the stabilization of helical conformation in alanine-based short peptides using circular dichroism (CD) with water and methanol as solvent. A1 (Ac-Pro-Pro-Ala-Lys-Ala-Lys-Ala-Lys-Ala-NH2 ) is designed to assess the effect of N-terminal homochiral diproline and lysine side chains to induce helical conformation. A2 (Ac-Pro-Pro-Glu-Glu-Ala-Ala-Lys-Lys-Ala-NH2 ) and A3 (Ac-dPro-Pro-Glu-Glu-Ala-Ala-Lys-Lys-Ala-NH2 ) with N-terminal homochiral and heterochiral diproline, respectively, are designed to assess the effect of Glu...Lys (i, i + 4) salt bridge interactions on the stabilization of helical conformation. The CD spectra of A1, A2 and A3 in water manifest different amplitudes of the observed polyproline II (PPII) signals, which indicate different conformational distributions of the polypeptide structure. The strong effect of solvent substitution from water to methanol is observed for the peptides, and CD spectra in methanol evidence A2 and A3 as helical folds. Temperature-dependent CD spectra of A1 and A2 in water depict an isodichroic point reflecting coexistence of two conformations, PPII and β-strand conformation, which is consistent with the previous studies. The results illuminate the effect of N-terminal diproline and charged side chains in dictating the preferences for extended-β, semi-extended PPII and helical conformation in alanine-based short peptides. The results of the present study will enhance our understanding on stabilization of helical conformation in short peptides and hence aid in the design of novel peptides with helical structures. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.
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Affiliation(s)
- Bhupesh Goyal
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.,Department of Chemistry, School of Basic and Applied Sciences, Sri Guru Granth Sahib World University, Fatehgarh Sahib, 140406, Punjab, India
| | - Kinshuk Raj Srivastava
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.,Life Sciences Institute, University of Michigan, Ann Arbor, MI, 48105, USA
| | - Susheel Durani
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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29
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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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30
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Lin F, Hossain MA, Post S, Karashchuk G, Tatar M, De Meyts P, Wade JD. Total Solid-Phase Synthesis of Biologically Active Drosophila Insulin-Like Peptide 2 (DILP2). Aust J Chem 2016; 70:208-212. [PMID: 29491510 DOI: 10.1071/ch16626] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In the fruit fly Drosophila melanogaster, there are eight insulin-like peptides (DILPs) with DILPs 1-7 interacting with a sole insulin-like receptor tyrosine kinase (DInR) while DILP8 interacts with a single G protein-coupled receptor (GPCR), Lgr3. Loss-of-function dilp mutation studies show that the neuropeptide DILP2 has a key role in carbohydrate and lipid metabolism as well as longevity and reproduction. A better understanding of the processes whereby DILP2 mediates its specific actions is required. Consequently we undertook to prepare DILP2 as part of a larger, detailed structure-function relationship study. Use of our well-established insulin-like peptide synthesis protocol that entails separate solid phase assembly of each of the A- and B-chains with selective cysteine S-protection followed by sequential S-deprotection and simultaneous disulfide bond formation produced DILP2 in good overall yield and high purity. The synthetic DILP2 was shown to induce significant DInR phosphorylation and downstream signalling, with it being more potent than human insulin. This peptide will be a valuable tool to provide further insights into its binding to the insulin receptor, the subsequent cell signalling and role in insect metabolism.
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Affiliation(s)
- Feng Lin
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria 3010, Australia
| | - Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria 3010, Australia.,School of Chemistry University of Melbourne, Victoria 3010, Australia
| | - Stephanie Post
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
| | - Galina Karashchuk
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
| | - Marc Tatar
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02912, USA
| | - Pierre De Meyts
- de Duve Institute, 1200 Brussels, Belgium and Novo Nordisk A/S, Måløv, Denmark
| | - John D Wade
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Victoria 3010, Australia.,School of Chemistry University of Melbourne, Victoria 3010, Australia
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31
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Patil NA, Tailhades J, Karas JA, Separovic F, Wade JD, Hossain MA. A One-Pot Chemically Cleavable Bis-Linker Tether Strategy for the Synthesis of Heterodimeric Peptides. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604733] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Nitin A. Patil
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne VIC 3010 Australia
- School of Chemistry; University of Melbourne; Melbourne VIC 3010 Australia
- Bio21 Institute; University of Melbourne; Australia
| | - Julien Tailhades
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne VIC 3010 Australia
| | - John A. Karas
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne VIC 3010 Australia
- School of Chemistry; University of Melbourne; Melbourne VIC 3010 Australia
- Bio21 Institute; University of Melbourne; Australia
| | - Frances Separovic
- School of Chemistry; University of Melbourne; Melbourne VIC 3010 Australia
- Bio21 Institute; University of Melbourne; Australia
| | - John D. Wade
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne VIC 3010 Australia
- School of Chemistry; University of Melbourne; Melbourne VIC 3010 Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health; The University of Melbourne; Melbourne VIC 3010 Australia
- School of Chemistry; University of Melbourne; Melbourne VIC 3010 Australia
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32
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Patil NA, Tailhades J, Karas JA, Separovic F, Wade JD, Hossain MA. A One-Pot Chemically Cleavable Bis-Linker Tether Strategy for the Synthesis of Heterodimeric Peptides. Angew Chem Int Ed Engl 2016; 55:14552-14556. [PMID: 27529162 DOI: 10.1002/anie.201604733] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2016] [Revised: 07/14/2016] [Indexed: 12/21/2022]
Abstract
Heterodimeric peptides linked by disulfide bonds are attractive drug targets. However, their chemical assembly can be tedious, time-consuming, and low yielding. Inspired by the cellular synthesis of pro-insulin in which the two constituent peptide chains are expressed as a single-chain precursor separated by a connecting C-peptide, we have developed a novel chemically cleavable bis-linker tether which allows the convenient assembly of two peptide chains as a single "pro"-peptide on the same solid support. Following the peptide cleavage and post-synthetic modifications, this bis-linker tether can be removed in one-step by chemical means. This method was used to synthesize a drug delivery-cargo conjugate, TAT-PKCi peptide, and a two-disulfide bridged heterodimeric peptide, thionin (7-19)-(24-32R), a thionin analogue. To our knowledge, this is the first report of a one-pot chemically cleavable bis-linker strategy for the facile synthesis of cross-bridged two-chain peptides.
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Affiliation(s)
- Nitin A Patil
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, 3010, Australia.,School of Chemistry, University of Melbourne, Melbourne, VIC, 3010, Australia.,Bio21 Institute, University of Melbourne, Australia
| | - Julien Tailhades
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - John A Karas
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, 3010, Australia.,School of Chemistry, University of Melbourne, Melbourne, VIC, 3010, Australia.,Bio21 Institute, University of Melbourne, Australia
| | - Frances Separovic
- School of Chemistry, University of Melbourne, Melbourne, VIC, 3010, Australia.,Bio21 Institute, University of Melbourne, Australia
| | - John D Wade
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, 3010, Australia.,School of Chemistry, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, 3010, Australia.,School of Chemistry, University of Melbourne, Melbourne, VIC, 3010, Australia
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33
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Hojo K, Hossain MA, Tailhades J, Shabanpoor F, Wong LLL, Ong-Pålsson EEK, Kastman HE, Ma S, Gundlach AL, Rosengren KJ, Wade JD, Bathgate RAD. Development of a Single-Chain Peptide Agonist of the Relaxin-3 Receptor Using Hydrocarbon Stapling. J Med Chem 2016; 59:7445-56. [PMID: 27464307 DOI: 10.1021/acs.jmedchem.6b00265] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Structure-activity studies of the insulin superfamily member, relaxin-3, have shown that its G protein-coupled receptor (RXFP3) binding site is contained within its central B-chain α-helix and this helical structure is essential for receptor activation. We sought to develop a single B-chain mimetic that retained agonist activity. This was achieved by use of solid phase peptide synthesis together with on-resin ruthenium-catalyzed ring closure metathesis of a pair of judiciously placed i,i+4 α-methyl, α-alkenyl amino acids. The resulting hydrocarbon stapled peptide was shown by solution NMR spectroscopy to mimic the native helical conformation of relaxin-3 and to possess potent RXFP3 receptor binding and activation. Alternative stapling procedures were unsuccessful, highlighting the critical need to carefully consider both the peptide sequence and stapling methodology for optimal outcomes. Our result is the first successful minimization of an insulin-like peptide to a single-chain α-helical peptide agonist which will facilitate study of the function of relaxin-3.
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Affiliation(s)
- Keiko Hojo
- Faculty of Pharmaceutical Sciences and Cooperative Research Center of Life Sciences, Kobe Gakuin University , Chuo-ku, Kobe 650-8586, Japan
| | - Mohammed Akhter Hossain
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.,School of Chemistry, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Julien Tailhades
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Fazel Shabanpoor
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.,School of Chemistry, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Lilian L L Wong
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Emma E K Ong-Pålsson
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Hanna E Kastman
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Sherie Ma
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Andrew L Gundlach
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.,Department of Anatomy and Neuroscience, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - K Johan Rosengren
- School of Biomedical Sciences, The University of Queensland , Brisbane, Queensland 4072, Australia
| | - John D Wade
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.,School of Chemistry, University of Melbourne , Melbourne, Victoria 3052, Australia
| | - Ross A D Bathgate
- Florey Institute of Neuroscience and Mental Health and Florey Department of Neuroscience and Mental Health, University of Melbourne , Melbourne, Victoria 3052, Australia.,Department of Biochemistry and Molecular Biology, University of Melbourne , Melbourne, Victoria 3052, Australia
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34
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Ang SY, Hutchinson DS, Patil N, Evans BA, Bathgate RAD, Halls ML, Hossain MA, Summers RJ, Kocan M. Signal transduction pathways activated by insulin-like peptide 5 at the relaxin family peptide RXFP4 receptor. Br J Pharmacol 2016; 174:1077-1089. [PMID: 27243554 DOI: 10.1111/bph.13522] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 05/06/2016] [Accepted: 05/11/2016] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND AND PURPOSE Insulin-like peptide 5 (INSL5) is a two-chain, three-disulfide-bonded peptide of the insulin/relaxin superfamily, uniquely expressed in enteroendocrine L-cells of the colon. It is the cognate ligand of relaxin family peptide RXFP4 receptor that is mainly expressed in the colorectum and enteric nervous system. This study identifies new signalling pathways activated by INSL5 acting on RXFP4 receptors. EXPERIMENTAL APPROACH INSL5/RXFP4 receptor signalling was investigated using AlphaScreen® proximity assays. Recruitment of Gαi/o proteins by RXFP4 receptors was determined by rescue of Pertussis toxin (PTX)-inhibited cAMP and ERK1/2 responses following transient transfection of PTX-insensitive Gαi/o C351I mutants. Cell proliferation was studied with bromodeoxyuridine. RXFP4 receptor interactions with β-arrestins, GPCR kinase 2 (GRK2), KRas and Rab5a was assessed with real-time BRET. Gene expression was investigated using real-time quantitative PCR. Insulin release was measured using HTRF and intracellular Ca2+ flux monitored in a Flexstation® using Fluo-4-AM. KEY RESULTS INSL5 inhibited forskolin-stimulated cAMP accumulation and increased phosphorylation of ERK1/2, p38MAPK, Akt Ser473 , Akt Thr308 and S6 ribosomal protein. cAMP and ERK1/2 responses were abolished by PTX and rescued by mGαoA , mGαoB and mGαi2 and to a lesser extent mGαi1 and mGαi3 . RXFP4 receptors interacted with GRK2 and β-arrestins, moved towards Rab5a and away from KRas, indicating internalisation following receptor activation. INSL5 inhibited glucose-stimulated insulin secretion and Ca2+ mobilisation in MIN6 insulinoma cells and forskolin-stimulated cAMP accumulation in NCI-H716 enteroendocrine cells. CONCLUSIONS AND IMPLICATIONS Knowledge of signalling pathways activated by INSL5 at RXFP4 receptors is essential for understanding the biological roles of this novel gut hormone. 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)
- Sheng Y Ang
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Dana S Hutchinson
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia.,Department of Pharmacology, Monash University, Clayton, VIC, Australia
| | - Nitin Patil
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Bronwyn A Evans
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, 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
| | - Michelle L Halls
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Mohammed A Hossain
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Roger J Summers
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Martina Kocan
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
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35
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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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36
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Wu F, Mayer JP, Zaykov AN, Zhang F, Liu F, DiMarchi RD. Chemical Synthesis of Human Insulin-Like Peptide-6. Chemistry 2016; 22:9777-83. [DOI: 10.1002/chem.201601410] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Indexed: 01/06/2023]
Affiliation(s)
- Fangzhou Wu
- Department of Chemistry; Indiana University Bloomington; 800 E. Kirkwood Avenue Bloomington Indiana 47405 USA
| | - John P. Mayer
- Department of Chemistry; Indiana University Bloomington; 800 E. Kirkwood Avenue Bloomington Indiana 47405 USA
| | - Alexander N. Zaykov
- Department of Chemistry; Indiana University Bloomington; 800 E. Kirkwood Avenue Bloomington Indiana 47405 USA
| | - Fa Zhang
- Department of Chemistry; Indiana University Bloomington; 800 E. Kirkwood Avenue Bloomington Indiana 47405 USA
| | - Fa Liu
- Novo Nordisk Research Center Indianapolis; 5225 Exploration Drive Indianapolis Indiana 46241 USA
| | - Richard D. DiMarchi
- Department of Chemistry; Indiana University Bloomington; 800 E. Kirkwood Avenue Bloomington Indiana 47405 USA
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37
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Liu F, Zaykov AN, Levy JJ, DiMarchi RD, Mayer JP. Chemical synthesis of peptides within the insulin superfamily. J Pept Sci 2016; 22:260-70. [PMID: 26910514 DOI: 10.1002/psc.2863] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 01/07/2016] [Accepted: 01/13/2016] [Indexed: 12/21/2022]
Abstract
The synthesis of insulin has inspired fundamental advances in the art of peptide science while simultaneously revealing the structure-function relationship of this centrally important metabolic hormone. This review highlights milestones in the chemical synthesis of insulin that can be divided into two separate approaches: (i) disulfide bond formation driven by protein folding and (ii) chemical reactivity-directed sequential disulfide bond formation. Common to the two approaches are the persistent challenges presented by the hydrophobic nature of the individual A-chain and B-chain and the need for selective disulfide formation under mildly oxidative conditions. The extension and elaboration of these synthetic approaches have been ongoing within the broader insulin superfamily. These structurally similar peptides include the insulin-like growth factors and also the related peptides such as relaxin that signal through G-protein-coupled receptors. After a half-century of advances in insulin chemistry, we have reached a point where synthesis is no longer limiting structural and biological investigation within this family of peptide hormones. The future will increasingly focus on the refinement of structure to meet medicinal purposes that have long been pursued, such as the development of a glucose-sensitive insulin. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.
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Affiliation(s)
- Fa Liu
- Calibrium LLC, 11711 N. Meridian Street, Carmel, IN, 46032, USA
| | - Alexander N Zaykov
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN, 47405, USA
| | - Jay J Levy
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN, 47405, USA
| | - Richard D DiMarchi
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN, 47405, USA
| | - John P Mayer
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN, 47405, USA
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38
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Patil NA, Hughes RA, Rosengren KJ, Kocan M, Ang SY, Tailhades J, Separovic F, Summers RJ, Grosse J, Wade JD, Bathgate RAD, Hossain MA. Engineering of a Novel Simplified Human Insulin-Like Peptide 5 Agonist. J Med Chem 2016; 59:2118-25. [PMID: 26824523 DOI: 10.1021/acs.jmedchem.5b01786] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Insulin-like peptide 5 (INSL5) has recently been discovered as only the second orexigenic gut hormone after ghrelin. As we have previously reported, INSL5 is extremely difficult to assemble and oxidize into its two-chain three-disulfide structure. The focus of this study was to generate structure-activity relationships (SARs) of INSL5 and use it to develop a potent and simpler INSL5 mimetic with RXFP4 agonist activity. A series of human and mouse INSL5 (hINSL5/mINSL5) analogues were designed and chemically synthesized, resulting in a chimeric INSL5 analogue exhibiting more than 10-fold higher potency (0.35 nM) at human RXFP4 compared with native hINSL5 (4.57 nM). The SAR study also identified a key residue (K(A15)) in the A-chain of mINSL5 that contributes to improved RXFP4 affinity and potency of mINSL5 compared with hINSL5. This knowledge ultimately led us to engineer a minimized hINSL5 mimetic agonist that retains native hINSL5-like RXFP4 affinity and potency at human RXFP4. This minimized analogue was synthesized in 17.5-fold higher yield and in less time compared with hINSL5.
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Affiliation(s)
| | | | - K Johan Rosengren
- School of Biomedical Sciences, The University of Queensland , Brisbane, QLD 4072, Australia
| | - Martina Kocan
- Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | - Sheng Yu Ang
- Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
| | | | | | - Roger J Summers
- Monash Institute of Pharmaceutical Sciences, Monash University , Parkville, VIC 3052, Australia
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39
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Zeng W, Horrocks KJ, Tan ACL, Jackson DC. Chemical Synthesis of Monomeric, Dimeric and Tetrameric Forms of the Ectodomain of Influenza Matrix 2 Protein. European J Org Chem 2016. [DOI: 10.1002/ejoc.201501569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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40
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Patil NA, Bathgate RAD, Kocan M, Ang SY, Tailhades J, Separovic F, Summers R, Grosse J, Hughes RA, Wade JD, Hossain MA. The C-terminus of the B-chain of human insulin-like peptide 5 is critical for cognate RXFP4 receptor activity. Amino Acids 2015; 48:987-992. [PMID: 26661035 DOI: 10.1007/s00726-015-2144-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 11/22/2015] [Indexed: 11/26/2022]
Abstract
Insulin-like peptide 5 (INSL5) is an orexigenic peptide hormone belonging to the relaxin family of peptides. It is expressed primarily in the L-cells of the colon and has a postulated key role in regulating food intake. Its G protein-coupled receptor, RXFP4, is a potential drug target for treating obesity and anorexia. We studied the effect of modification of the C-terminus of the A and B-chains of human INSL5 on RXFP4 binding and activation. Three variants of human INSL5 were prepared using solid phase peptide synthesis and subsequent sequential regioselective disulfide bond formation. The peptides were synthesized as C-terminal acids (both A- and B-chains with free C-termini, i.e., the native form), amides (both chains as the C-terminal amide) and one analog with the C-terminus of its A-chain as the amide and the C-terminus of the B-chain as the acid. The results showed that C-terminus of the B-chain is more important than that of the A-chain for RXFP4 binding and activity. Amidation of the A-chain C-terminus does not have any effect on the INSL5 activity. The difference in RXFP4 binding and activation between the three peptides is believed to be due to electrostatic interaction of the free carboxylate of INSL5 with a positively charged residue (s), either situated within the INSL5 molecule itself or in the receptor extracellular loops.
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Affiliation(s)
- Nitin A Patil
- Howard Florey Research Laboratories, Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Ross A D Bathgate
- Howard Florey Research Laboratories, Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
- Department of Biochemistry and Molecular Biology, University of Melbourne, Melbourne, VIC, Australia
| | - Martina Kocan
- Monash Institute of Pharmaceutical Sciences, Parkville, VIC, Australia
| | - Sheng Yu Ang
- Monash Institute of Pharmaceutical Sciences, Parkville, VIC, Australia
| | - Julien Tailhades
- Howard Florey Research Laboratories, Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia
| | - Roger Summers
- Monash Institute of Pharmaceutical Sciences, Parkville, VIC, Australia
| | | | - Richard A Hughes
- Department of Pharmacology, University of Melbourne, Melbourne, VIC, Australia
| | - John D Wade
- Howard Florey Research Laboratories, Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia.
| | - Mohammed Akhter Hossain
- Howard Florey Research Laboratories, Florey Institute for Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia.
- School of Chemistry, Bio21 Institute, University of Melbourne, Melbourne, VIC, Australia.
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41
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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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42
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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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43
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Tailhades J, Patil NA, Hossain MA, Wade JD. Intramolecular acyl transfer in peptide and protein ligation and synthesis. J Pept Sci 2015; 21:139-47. [DOI: 10.1002/psc.2749] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/25/2014] [Accepted: 12/27/2014] [Indexed: 12/18/2022]
Affiliation(s)
- Julien Tailhades
- The Florey Institute of Neuroscience and Mental Health; University of Melbourne; Victoria 3010 Australia
| | - Nitin A. Patil
- The Florey Institute of Neuroscience and Mental Health; University of Melbourne; Victoria 3010 Australia
- School of Chemistry; University of Melbourne; Victoria 3010 Australia
| | - Mohammed Akhter Hossain
- The Florey Institute of Neuroscience and Mental Health; University of Melbourne; Victoria 3010 Australia
- School of Chemistry; University of Melbourne; Victoria 3010 Australia
| | - John D. Wade
- The Florey Institute of Neuroscience and Mental Health; University of Melbourne; Victoria 3010 Australia
- School of Chemistry; University of Melbourne; Victoria 3010 Australia
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44
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Synthetic covalently linked dimeric form of H2 relaxin retains native RXFP1 activity and has improved in vitro serum stability. BIOMED RESEARCH INTERNATIONAL 2015; 2015:731852. [PMID: 25685807 PMCID: PMC4317577 DOI: 10.1155/2015/731852] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 10/11/2014] [Indexed: 11/18/2022]
Abstract
Human (H2) relaxin is a two-chain peptide member of the insulin superfamily and possesses potent pleiotropic roles including regulation of connective tissue remodeling and systemic and renal vasodilation. These effects are mediated through interaction with its cognate G-protein-coupled receptor, RXFP1. H2 relaxin recently passed Phase III clinical trials for the treatment of congestive heart failure. However, its in vivo half-life is short due to its susceptibility to proteolytic degradation and renal clearance. To increase its residence time, a covalent dimer of H2 relaxin was designed and assembled through solid phase synthesis of the two chains, including a judiciously monoalkyne sited B-chain, followed by their combination through regioselective disulfide bond formation. Use of a bisazido PEG7 linker and "click" chemistry afforded a dimeric H2 relaxin with its active site structurally unhindered. The resulting peptide possessed a similar secondary structure to the native monomeric H2 relaxin and bound to and activated RXFP1 equally well. It had fewer propensities to activate RXFP2, the receptor for the related insulin-like peptide 3. In human serum, the dimer had a modestly increased half-life compared to the monomeric H2 relaxin suggesting that additional oligomerization may be a viable strategy for producing longer acting variants of H2 relaxin.
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45
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Diepenhorst NA, Petrie EJ, Chen CZ, Wang A, Hossain MA, Bathgate RAD, Gooley PR. Investigation of interactions at the extracellular loops of the relaxin family peptide receptor 1 (RXFP1). J Biol Chem 2014; 289:34938-52. [PMID: 25352603 DOI: 10.1074/jbc.m114.600882] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Relaxin, an emerging pharmaceutical treatment for acute heart failure, activates the relaxin family peptide receptor (RXFP1), which is a class A G-protein-coupled receptor. In addition to the classic transmembrane (TM) domain, RXFP1 possesses a large extracellular domain consisting of 10 leucine-rich repeats and an N-terminal low density lipoprotein class A (LDLa) module. Relaxin-mediated activation of RXFP1 requires multiple coordinated interactions between the ligand and various receptor domains including a high affinity interaction involving the leucine-rich repeats and a predicted lower affinity interaction involving the extracellular loops (ELs). The LDLa is essential for signal activation; therefore the ELs/TM may additionally present an interaction site to facilitate this LDLa-mediated signaling. To overcome the many challenges of investigating relaxin and the LDLa module interactions with the ELs, we engineered the EL1 and EL2 loops onto a soluble protein scaffold, mapping specific ligand and loop interactions using nuclear magnetic resonance spectroscopy. Key EL residues were subsequently mutated in RXFP1, and changes in function and relaxin binding were assessed alongside the RXFP1 agonist ML290 to monitor the functional integrity of the TM domain of these mutant receptors. The outcomes of this work make an important contribution to understanding the mechanism of RXFP1 activation and will aid future development of small molecule RXFP1 agonists/antagonists.
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Affiliation(s)
- Natalie A Diepenhorst
- From the Florey Institute of Neuroscience and Mental Health, the Department of Biochemistry and Molecular Biology, and
| | - Emma J Petrie
- the Department of Biochemistry and Molecular Biology, and
| | - Catherine Z Chen
- the National Center for Advancing Translational Sciences, Division of Preclinical Innovation, National Institutes of Health, Rockville, Maryland 20850
| | - Amy Wang
- the National Center for Advancing Translational Sciences, Division of Preclinical Innovation, National Institutes of Health, Rockville, Maryland 20850
| | - Mohammed Akhter Hossain
- From the Florey Institute of Neuroscience and Mental Health, the School of Chemistry, University of Melbourne, Parkville, Victoria 3010, Australia and
| | - Ross A D Bathgate
- From the Florey Institute of Neuroscience and Mental Health, the Department of Biochemistry and Molecular Biology, and
| | - Paul R Gooley
- the Department of Biochemistry and Molecular Biology, and
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46
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Abstract
The gut endocrine system is emerging as a central player in the control of appetite and glucose homeostasis, and as a rich source of peptides with therapeutic potential in the field of diabetes and obesity. In this study we have explored the physiology of insulin-like peptide 5 (Insl5), which we identified as a product of colonic enteroendocrine L-cells, better known for their secretion of glucagon-like peptide-1 and peptideYY. i.p. Insl5 increased food intake in wild-type mice but not mice lacking the cognate receptor Rxfp4. Plasma Insl5 levels were elevated by fasting or prolonged calorie restriction, and declined with feeding. We conclude that Insl5 is an orexigenic hormone released from colonic L-cells, which promotes appetite during conditions of energy deprivation.
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47
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Karas JA, Scanlon DB, Forbes BE, Vetter I, Lewis RJ, Gardiner J, Separovic F, Wade JD, Hossain MA. 2-Nitroveratryl as a Photocleavable Thiol-Protecting Group for Directed Disulfide Bond Formation in the Chemical Synthesis of Insulin. Chemistry 2014; 20:9549-52. [DOI: 10.1002/chem.201403574] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Indexed: 12/20/2022]
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48
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Liu F, Liu Q, Mezo AR. An Iodine-Free and Directed-Disulfide-Bond-Forming Route to Insulin Analogues. Org Lett 2014; 16:3126-9. [DOI: 10.1021/ol501252b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Fa Liu
- Lilly Research Laboratories, Indianapolis, Indiana 46285, United States
| | - Qingyuan Liu
- Lilly Research Laboratories, Indianapolis, Indiana 46285, United States
| | - Adam R. Mezo
- Lilly Research Laboratories, Indianapolis, Indiana 46285, United States
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49
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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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Belgi A, Bathgate RAD, Kocan M, Patil N, Zhang S, Tregear GW, Wade JD, Hossain MA. Minimum active structure of insulin-like peptide 5. J Med Chem 2013; 56:9509-16. [PMID: 24188028 DOI: 10.1021/jm400924p] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Insulin-like peptide 5 (INSL5) is a complex two-chain peptide hormone constrained by three disulfide bonds in a pattern identical to insulin. High expression of INSL5 in the colon suggests roles in activation of colon motility and appetite control. A more recent study indicates it may have significant roles in the regulation of insulin secretion and β-cell homeostasis. This peptide thus has considerable potential for the treatment of eating disorders, obesity, and/or diabetes. However, the synthesis of INSL5 is extremely challenging either by chemical or recombinant means. The A-chain is very poorly soluble and the B-chain is highly aggregating in nature which, together, makes their postsynthesis handling and purification very difficult. Given these difficulties, we have developed a highly active INSL5 analogue that has a much simpler structure with two disulfide bonds and is thus easier to assemble compared to native INSL5. This minimized peptide represents an attractive new mimetic for investigating the functional role of INSL5.
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Affiliation(s)
- Alessia Belgi
- Florey Institute of Neuroscience and Mental Health, ‡Department of Biochemistry and Molecular Biology, §Florey Department of Neuroscience and Mental Health, and ∥School of Chemistry, The University of Melbourne , Victoria 3010, Australia
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