1
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Franklin ZJ, Lafferty RA, Flatt PR, McShane LM, O'Harte FP, Irwin N. Metabolic effects of combined glucagon receptor antagonism and glucagon-like peptide-1 receptor agonism in high fat fed mice. Biochimie 2022; 199:60-67. [DOI: 10.1016/j.biochi.2022.04.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/05/2022] [Accepted: 04/13/2022] [Indexed: 01/19/2023]
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2
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Conlon JM, O'Harte FPM, Flatt PR. Dual-agonist incretin peptides from fish with potential for obesity-related Type 2 diabetes therapy - A review. Peptides 2022; 147:170706. [PMID: 34861327 DOI: 10.1016/j.peptides.2021.170706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 12/25/2022]
Abstract
The long-acting glucagon-like peptide-1 receptor (GLP1R) agonist, semaglutide and the unimolecular glucose-dependent insulinotropic polypeptide receptor (GIPR)/GLP1R dual-agonist, tirzepatide have been successfully introduced as therapeutic options for patients with Type-2 diabetes (T2DM) and obesity. Proglucagon-derived peptides from phylogenetically ancient fish act as naturally occurring dual agonists at the GLP1R and the glucagon receptor (GCGR) with lamprey GLP-1 and paddlefish glucagon being the most potent and effective in stimulating insulin release from BRIN-BD11 clonal β-cells. These peptides were also the most effective in lowering blood glucose and elevating plasma insulin concentrations when administered intraperitoneally to overnight-fasted mice together with a glucose load. Zebrafish GIP acts as a dual agonist at the GIPR and GLP1R receptors. Studies with the high fat-fed mouse, an animal model with obesity, impaired glucose-tolerance and insulin-resistance, have shown that twice-daily administration of the long-acting analogs [D-Ala2]palmitoyl-lamprey GLP-1 and [D-Ser2]palmitoyl-paddlefish glucagon over 21 days improves glucose tolerance and insulin sensitivity. This was associated with β-cell proliferation, protection of β-cells against apoptosis, decreased pancreatic glucagon content, improved lipid profile, reduced food intake and selective alteration in the expression of genes involved in β-cell stimulus-secretion coupling. In insulin-deficient GluCreERT2;ROSA26-eYFP transgenic mice, the peptides promoted an increase in β-cell mass with positive effects on transdifferentiation of glucagon-producing to insulin-producing cells. Naturally occurring fish dual agonist peptides, particularly lamprey GLP-1 and paddlefish glucagon, provide templates for development into therapeutic agents for obesity-related T2DM.
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Affiliation(s)
- J Michael Conlon
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK.
| | - Finbarr P M O'Harte
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
| | - Peter R Flatt
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
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3
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Lafferty RA, O’Harte FPM, Irwin N, Gault VA, Flatt PR. Proglucagon-Derived Peptides as Therapeutics. Front Endocrinol (Lausanne) 2021; 12:689678. [PMID: 34093449 PMCID: PMC8171296 DOI: 10.3389/fendo.2021.689678] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 05/05/2021] [Indexed: 12/12/2022] Open
Abstract
Initially discovered as an impurity in insulin preparations, our understanding of the hyperglycaemic hormone glucagon has evolved markedly over subsequent decades. With description of the precursor proglucagon, we now appreciate that glucagon was just the first proglucagon-derived peptide (PGDP) to be characterised. Other bioactive members of the PGDP family include glucagon-like peptides -1 and -2 (GLP-1 and GLP-2), oxyntomodulin (OXM), glicentin and glicentin-related pancreatic peptide (GRPP), with these being produced via tissue-specific processing of proglucagon by the prohormone convertase (PC) enzymes, PC1/3 and PC2. PGDP peptides exert unique physiological effects that influence metabolism and energy regulation, which has witnessed several of them exploited in the form of long-acting, enzymatically resistant analogues for treatment of various pathologies. As such, intramuscular glucagon is well established in rescue of hypoglycaemia, while GLP-2 analogues are indicated in the management of short bowel syndrome. Furthermore, since approval of the first GLP-1 mimetic for the management of Type 2 diabetes mellitus (T2DM) in 2005, GLP-1 therapeutics have become a mainstay of T2DM management due to multifaceted and sustainable improvements in glycaemia, appetite control and weight loss. More recently, longer-acting PGDP therapeutics have been developed, while newfound benefits on cardioprotection, bone health, renal and liver function and cognition have been uncovered. In the present article, we discuss the physiology of PGDP peptides and their therapeutic applications, with a focus on successful design of analogues including dual and triple PGDP receptor agonists currently in clinical development.
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Affiliation(s)
| | | | | | - Victor A. Gault
- School of Biomedical Sciences, Ulster University, Coleraine, United Kingdom
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4
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Graham GV, Conlon JM, Moffett RC, Abdel-Wahab YH, Flatt PR. Effects of long-acting analogues of lamprey GLP-1 and paddlefish glucagon on alpha- to beta-cell transdifferentiation in an insulin-deficient transgenic mouse model. J Pept Sci 2021; 27:e3328. [PMID: 33843129 DOI: 10.1002/psc.3328] [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: 02/13/2021] [Revised: 03/21/2021] [Accepted: 03/23/2021] [Indexed: 12/20/2022]
Abstract
The abilities of the long-acting, dual-agonist anti-diabetic peptides [D-Ala2 ]palmitoyl-lamprey GLP-1 and [D-Ser2 ]palmitoyl-paddlefish glucagon to induce α-cell to β-cell transdifferentiation were investigated in GluCreERT2 ;ROSA26-eYFP mice. These animals have been genetically engineered so that yellow fluorescent protein is specifically expressed in glucagon-producing α-cells, thereby allowing cell lineage tracing. Insulin deficiency was produced by treatment of the mice with multiple low doses of streptozotocin. Administration of the peptides (twice daily intraperitoneal injections of 25 nmol/kg body weight over 10 days) to streptozotocin-treated mice produced significant (P < 0.05) increases in pancreatic insulin content and plasma insulin concentrations compared with control mice. Immunohistochemical studies demonstrated a significant (P < 0.05) increase in the % of cells staining for both insulin and fluorescent protein in islets located in the head region of the pancreas (from 10.0 ± 1.3% of total cells in untreated mice to 20.0 ± 3.85% in mice treated with D-Ala2 ]palmitoyl-lamprey GLP-1 and to 17.3 ± 1.1% in mice treated with [D-Ser2 ]palmitoyl-paddlefish glucagon). Corresponding effects upon islets in the tail region were not significant. The data indicate an improvement in β-cell mass and positive effects on transdifferentiation of glucagon-producing to insulin-producing cells. The study provides further evidence that proglucagon-derived peptides from phylogenetical ancient fish show therapeutic potential for treatment of diabetes.
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Affiliation(s)
- Galyna V Graham
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK
| | - J Michael Conlon
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK
| | - R Charlotte Moffett
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK
| | - Yasser H Abdel-Wahab
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK
| | - Peter R Flatt
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, UK
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Graham GV, Conlon JM, Abdel-Wahab YH, Flatt PR. Glucagon from the phylogenetically ancient paddlefish provides a template for the design of a long-acting peptide with effective anti-diabetic and anti-obesity activities. Eur J Pharmacol 2020; 878:173101. [PMID: 32320703 DOI: 10.1016/j.ejphar.2020.173101] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 03/26/2020] [Accepted: 04/06/2020] [Indexed: 12/13/2022]
Abstract
This study has examined the in vitro and in vivo anti-diabetic properties of the peptidase-resistant analogues [D-Ser2]palmitoyl-paddlefish glucagon and [D-Ser2]palmitoyl-lamprey glucagon. The peptides stimulated insulin release from BRIN-BD11 clonal β-cells and isolated mouse pancreatic islets and also enhanced cAMP production in cells transfected with the human GLP-1 receptor and with the human glucagon receptor. The insulinotropic actions of the peptides were attenuated in INS-1 cells lacking GLP-1 and glucagon receptors. [D-Ser2]palmitoyl-paddlefish glucagon stimulated proliferation of BRIN-BD11 cells and protected against cytokine-mediated apoptosis as effectively as GLP-1. The analogue was more effective than the native peptide or the lamprey glucagon analogue in acutely lowering blood glucose and elevating plasma insulin in lean mice even when administered up to 4 h before a glucose load. Twice daily administration of [D-Ser2]palmitoyl-paddlefish glucagon to high-fat fed mice over 21 days reduced food intake, body weight, non-fasting blood glucose and plasma insulin concentrations, as well as significantly improving glucose tolerance and insulin resistance and decreasing α-cell area and pancreatic insulin content. Islet expression of the Gcgr, Glp1r, Gipr and Slc2a2 (GLUT-2) genes significantly increased. These data demonstrate that long-acting peptide [D-Ser2]palmitoyl-paddlefish glucagon exerts beneficial metabolic properties in diabetic mice via Ggcr- and Glp1r-activated pathways and so shows potential as a template for further development into an agent for treatment of patients with obesity-related Type 2 diabetes.
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Affiliation(s)
- Galyna V Graham
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
| | - J Michael Conlon
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK.
| | - Yasser H Abdel-Wahab
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
| | - Peter R Flatt
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
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6
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Lafferty RA, Tanday N, McCloskey A, Bompada P, De Marinis Y, Flatt PR, Irwin N. Peptide YY (1-36) peptides from phylogenetically ancient fish targeting mammalian neuropeptide Y1 receptors demonstrate potent effects on pancreatic β-cell function, growth and survival. Diabetes Obes Metab 2020; 22:404-416. [PMID: 31692207 DOI: 10.1111/dom.13908] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/31/2019] [Accepted: 10/31/2019] [Indexed: 02/06/2023]
Abstract
AIM To investigate the antidiabetic efficacy of enzymatically stable Peptide YY (PYY) peptides from phylogenetically ancient fish. MATERIALS AND METHODS N-terminally stabilized, PYY (1-36) sequences from Amia calva (bowfin), Oncorhynchus mykiss (trout), Petromyzon marinus (sea lamprey) and Scaphirhynchus albus (sturgeon), were synthesized, and both biological actions and antidiabetic therapeutic efficacy were assessed. RESULTS All fish PYY (1-36) peptides were resistant to dipeptidyl peptidase-4 (DPP-4) degradation and inhibited glucose- and alanine-induced (P < 0.05 to P < 0.001) insulin secretion. In addition, PYY (1-36) peptides imparted significant (P < 0.05 to P < 0.001) β-cell proliferative and anti-apoptotic benefits. Proliferative effects were almost entirely absent in β cells with CRISPR-Cas9-induced knockout of Npyr1. In contrast to human PYY (1-36), the piscine-derived peptides lacked appetite-suppressive actions. Twice-daily administration of sea lamprey PYY (1-36), the superior bioactive peptide, for 21 days significantly (P < 0.05 to P < 0.001) decreased fluid intake, non-fasting glucose and glucagon in streptozotocin (STZ)-induced diabetic mice. In addition, glucose tolerance, insulin sensitivity, pancreatic insulin and glucagon content were significantly improved. Metabolic benefits were linked to positive changes in pancreatic islet morphology as a result of augmented (P < 0.001) proliferation and decreased apoptosis of β cells. Sturgeon PYY (1-36) exerted similar but less impressive effects in STZ mice. CONCLUSION These observations reveal, for the first time, that PYY (1-36) peptide sequences from phylogenetically ancient fish replicate the pancreatic β-cell benefits of human PYY (1-36) and have clear potential for the treatment of type 2 diabetes.
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Affiliation(s)
- Ryan A Lafferty
- SAAD Centre for Pharmacy and Diabetes, Biomedical Sciences Research Institute, University of Ulster, Coleraine, UK
| | - Neil Tanday
- SAAD Centre for Pharmacy and Diabetes, Biomedical Sciences Research Institute, University of Ulster, Coleraine, UK
| | - Andrew McCloskey
- SAAD Centre for Pharmacy and Diabetes, Biomedical Sciences Research Institute, University of Ulster, Coleraine, UK
| | - Pradeep Bompada
- Genomics, Diabetes and Endocrinology, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Yang De Marinis
- Genomics, Diabetes and Endocrinology, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Peter R Flatt
- SAAD Centre for Pharmacy and Diabetes, Biomedical Sciences Research Institute, University of Ulster, Coleraine, UK
| | - Nigel Irwin
- SAAD Centre for Pharmacy and Diabetes, Biomedical Sciences Research Institute, University of Ulster, Coleraine, UK
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7
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Graham GV, McCloskey A, Abdel-Wahab YH, Conlon JM, Flatt PR. A long-acting, dual-agonist analogue of lamprey GLP-1 shows potent insulinotropic, β-cell protective, and anorexic activities and improves glucose homeostasis in high fat-fed mice. Mol Cell Endocrinol 2020; 499:110584. [PMID: 31539596 DOI: 10.1016/j.mce.2019.110584] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/05/2019] [Accepted: 09/16/2019] [Indexed: 12/12/2022]
Abstract
Peptidase-resistant analogues of GLP-1 peptides from sea lamprey and paddlefish ([D-Ala2]palmitoyl-lamprey GLP-1 and [D-Ala2]palmitoyl-paddlefish GLP-1) produced significant (P ≤ 0.05) and concentration-dependent increases in insulin release from BRIN-BD11 clonal β-cells and from isolated mouse islets. Both analogues retained the ability of the native peptides to activate both the GLP-1 receptor (GLP1R) and the glucagon receptor (GCGR). [D-Ala2]palmitoyl-lamprey GLP-1 significantly (P < 0.001) stimulated proliferation of BRIN-BD11 cells and protected against cytokine-induced apoptosis. Administration of the lamprey analogue (25 nmol/kg body weight) to lean mice up to 4 h before a glucose load improved glucose tolerance and increased plasma insulin concentrations. Twice daily administration of the lamprey GLP-1 analogue to high fat-fed mice for 21 days decreased body weight, food intake, and circulating glucose and insulin concentrations. The analogue significantly improved glucose tolerance and insulin sensitivity with beneficial effects on islet β-cell area and insulin secretory responsiveness. Islet gene expression of Glp1r, Gcgr and Gipr significantly increased. The lamprey GLP-1 analogue shows therapeutic promise for treatment of patients with obesity-related Type 2 diabetes.
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Affiliation(s)
- Galyna V Graham
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland BT52 1SA, UK
| | - Andrew McCloskey
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland BT52 1SA, UK
| | - Yasser H Abdel-Wahab
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland BT52 1SA, UK
| | - J Michael Conlon
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland BT52 1SA, UK.
| | - Peter R Flatt
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Coleraine, Northern Ireland BT52 1SA, UK
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8
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Graham GV, Conlon JM, Abdel-Wahab YH, Flatt PR. Glucagon-like peptides-1 from phylogenetically ancient fish show potent anti-diabetic activities by acting as dual GLP1R and GCGR agonists. Mol Cell Endocrinol 2019; 480:54-64. [PMID: 30312651 DOI: 10.1016/j.mce.2018.10.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/08/2018] [Accepted: 10/08/2018] [Indexed: 12/24/2022]
Abstract
Glucagon-like peptides-1 (GLP-1)from phylogenetically ancient fish (lamprey, dogfish, ratfish, paddlefish and bowfin) and from a teleost, the rainbow trout produced concentration-dependent stimulations of insulin release from clonal β-cells and isolated mouse islets. Lamprey and paddlefish GLP-1 were the most potent and effective. Incubation of BRIN-BD11 cells with GLP-1 receptor (GLP1R) antagonist, exendin-4 (9-39) attenuated insulinotropic activity of all peptides whereas glucagon receptor (GCGR) antagonist [des-His1,Pro4,Glu9] glucagon amide significantly decreased the activities of lamprey and paddlefish GLP-1 only. The GIP receptor antagonist GIP (6-30) Cex-K40 [Pal] attenuated the activity of bowfin GLP-1. All peptides (1 μM) produced significant increases in cAMP concentration in CHL cells transfected with GLP1R but only lamprey and paddlefish GLP-1 stimulated cAMP production in HEK293 cells transfected with GCGR. Intraperitoneal administration of lamprey and paddlefish GLP-1 (25 nmol/kg body weight) in mice produced significant decreases in blood glucose and increased insulin concentrations comparable to the effects of human GLP-1. Lamprey and paddlefish GLP-1 display potent insulinotropic activity in vitro and glucose-lowering activity in vivo that is mediated through GLP1R and GCGR so that these peptides may constitute templates for design of new antidiabetic drugs.
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Affiliation(s)
- Galyna V Graham
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK
| | - J Michael Conlon
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK.
| | - Yasser H Abdel-Wahab
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK
| | - Peter R Flatt
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK
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9
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Graham GV, Conlon JM, Abdel-Wahab YH, Flatt PR. Glucagon-related peptides from phylogenetically ancient fish reveal new approaches to the development of dual GCGR and GLP1R agonists for type 2 diabetes therapy. Peptides 2018; 110:19-29. [PMID: 30391422 DOI: 10.1016/j.peptides.2018.10.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 10/29/2018] [Accepted: 10/30/2018] [Indexed: 12/11/2022]
Abstract
The insulinotropic and antihyperglycaemic properties of glucagons from the sea lamprey (Petromyzontiformes), paddlefish (Acipenseriformes) and trout (Teleostei) and oxyntomodulin from dogfish (Elasmobranchii) and ratfish (Holocephali) were compared with those of human glucagon and GLP-1 in mammalian test systems. All fish peptides produced concentration-dependent stimulation of insulin release from BRIN-BD11 rat and 1.1 B4 human clonal β-cells and isolated mouse islets. Paddlefish glucagon was the most potent and effective peptide. The insulinotropic activity of paddlefish glucagon was significantly (P < 0.01) decreased after incubating BRIN-BD11 cells with the GLP1R antagonist, exendin-4(9-39) and the GCGR antagonist [des-His1,Pro4, Glu9] glucagon amide but GIPR antagonist, GIP(6-30)Cex-K40[palmitate] was without effect. Paddlefish and lamprey glucagons and dogfish oxyntomodulin (10 nmol L-1) produced significant (P < 0.01) increases in cAMP concentration in Chinese hamster lung (CHL) cells transfected with GLP1R and human embryonic kidney (HEK293) cells transfected with GCGR. The insulinotropic activity of paddlefish glucagon was attenuated in CRISPR/Cas9-engineered GLP1R knock-out INS-1 cells but not in GIPR knock-out cells. Intraperitoneal administration of all fish peptides, except ratfish oxyntomodulin, to mice together with a glucose load produced significant (P < 0.05) decreases in plasma glucose concentrations and paddlefish glucagon produced a greater release of insulin compared with GLP-1. Paddlefish glucagon shares the sequences Glu15-Glu16 and Glu24-Trp25-Leu26-Lys27-Asn28-Gly29 with the potent GLP1R agonist, exendin-4 so may be regarded as a naturally occurring, dual-agonist hybrid peptide that may serve as a template design of new drugs for type 2 diabetes therapy.
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Affiliation(s)
- Galyna V Graham
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK
| | - J Michael Conlon
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK.
| | - Yasser H Abdel-Wahab
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK
| | - Peter R Flatt
- Diabetes Research Group, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland, BT52 1SA, UK
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10
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Elvert R, Herling AW, Bossart M, Weiss T, Zhang B, Wenski P, Wandschneider J, Kleutsch S, Butty U, Kannt A, Wagner M, Haack T, Evers A, Dudda A, Lorenz M, Keil S, Larsen PJ. Running on mixed fuel-dual agonistic approach of GLP-1 and GCG receptors leads to beneficial impact on body weight and blood glucose control: A comparative study between mice and non-human primates. Diabetes Obes Metab 2018; 20:1836-1851. [PMID: 29938884 PMCID: PMC6055720 DOI: 10.1111/dom.13212] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 12/11/2017] [Accepted: 12/25/2017] [Indexed: 12/17/2022]
Abstract
AIM We performed acute and chronic studies in healthy and diet-induced obese animals using mouse-specific or monkey-specific dual GLP-1R/GCGR agonists to investigate their effects on food intake, body weight, blood glucose control and insulin secretion. The selective GLP-1R agonist liraglutide was used as comparator. METHODS The mouse-specific dual agonist and liraglutide were tested in lean wild type, GLP-1R knockout and diet-induced obese mice at different doses. A chronic study was performed in DIO mice to investigate the effect on body weight, food consumption and total energy expenditure (TEE) in obese and diabetic monkeys with a focus on body weight and energy intake. RESULTS The mouse-specific dual agonist and liraglutide similarly affected glycaemic control. A higher loss in body weight was measured in dual agonist-treated obese mice. The dual agonist significantly enhanced plasma glucose excursion in overnight fed GLP-1R-/- mice, probably reflecting a potent GCGR agonist activity. It increased TEE and enhanced fat and carbohydrate oxidation, while liraglutide produced no effect on TEE. In obese and diabetic monkeys, treatment with the monkey-specific dual agonist reduced total energy intake to 60%-70% of baseline TEI during chronic treatment. A decrease in body weight and significant improvement in glucose tolerance was observed. CONCLUSIONS In DIO mice and non-human primates, dual agonists elicited robust glycaemic control, similar to the marketed GLP-1R agonist, while eliciting greater effects on body weight. Results from DIO mice suggest that the increase in TEE is caused not only by increased fat oxidation but also by an increase in carbohydrate oxidation.
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MESH Headings
- Animals
- Animals, Outbred Strains
- Appetite Depressants/administration & dosage
- Appetite Depressants/adverse effects
- Appetite Depressants/therapeutic use
- Body Weight/drug effects
- Diabetes Mellitus, Type 2/blood
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/metabolism
- Diet, High-Fat/adverse effects
- Dose-Response Relationship, Drug
- Drug Therapy, Combination/adverse effects
- Energy Intake/drug effects
- Energy Metabolism/drug effects
- Female
- Glucagon-Like Peptide-1 Receptor/agonists
- Glucagon-Like Peptide-1 Receptor/genetics
- Glucagon-Like Peptide-1 Receptor/metabolism
- Hyperglycemia/prevention & control
- Hypoglycemic Agents/administration & dosage
- Hypoglycemic Agents/adverse effects
- Hypoglycemic Agents/therapeutic use
- Insulin Secretion/drug effects
- Macaca fascicularis
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Obesity/blood
- Obesity/drug therapy
- Obesity/etiology
- Obesity/metabolism
- Random Allocation
- Receptors, Glucagon/agonists
- Receptors, Glucagon/metabolism
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Affiliation(s)
- Ralf Elvert
- Sanofi‐Aventis Deutschland GmbHFrankfurtGermany
| | | | | | - Tilo Weiss
- Sanofi‐Aventis Deutschland GmbHFrankfurtGermany
| | | | | | | | | | - Uwe Butty
- Sanofi‐Aventis Deutschland GmbHFrankfurtGermany
| | - Aimo Kannt
- Sanofi‐Aventis Deutschland GmbHFrankfurtGermany
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty MannheimHeidelberg UniversityMannheimGermany
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11
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Evers A, Bossart M, Pfeiffer-Marek S, Elvert R, Schreuder H, Kurz M, Stengelin S, Lorenz M, Herling A, Konkar A, Lukasczyk U, Pfenninger A, Lorenz K, Haack T, Kadereit D, Wagner M. Dual Glucagon-like Peptide 1 (GLP-1)/Glucagon Receptor Agonists Specifically Optimized for Multidose Formulations. J Med Chem 2018; 61:5580-5593. [DOI: 10.1021/acs.jmedchem.8b00292] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Andreas Evers
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Martin Bossart
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Stefania Pfeiffer-Marek
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Ralf Elvert
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Herman Schreuder
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Michael Kurz
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Siegfried Stengelin
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Martin Lorenz
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Andreas Herling
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Anish Konkar
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Ulrike Lukasczyk
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Anja Pfenninger
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Katrin Lorenz
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Torsten Haack
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Dieter Kadereit
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
| | - Michael Wagner
- Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, D-65926 Frankfurt am Main, Germany
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12
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Graham GV, Conlon JM, Abdel-Wahab YH, Gault VA, Flatt PR. Evaluation of the insulinotropic and glucose-lowering actions of zebrafish GIP in mammalian systems: Evidence for involvement of the GLP-1 receptor. Peptides 2018; 100:182-189. [PMID: 29157578 DOI: 10.1016/j.peptides.2017.11.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 11/10/2017] [Accepted: 11/15/2017] [Indexed: 12/31/2022]
Abstract
The insulinotropic properties of zebrafish GIP (zfGIP) were assessed in vitro using clonal pancreatic β-cell lines and isolated mouse islets and acute effects on glucose tolerance and insulin release in vivo were evaluated in mice. The peptide produced a dose-dependent increase in the rate of insulin release from BRIN-BD11 rat clonal β-cells at concentrations ≥30nM. Insulin release from 1.1 B4 human clonal β-cells and mouse islets was significantly increased by zfGIP (10nM and 1μM). The in vitro insulinotropic activity of zfGIP was decreased after incubating BRIN-BD11 cells with the GLP-1 receptor antagonist, exendin-4(9-39) (p<0.001) and the GIP receptor antagonist, GIP (6-30) Cex-K40[Pal] (p<0.05) but the glucagon receptor antagonist [des-His1,Pro4,Glu9]glucagon amide was without effect. zfGIP (10nM and 1μM) produced significant increases in cAMP concentration in CHL cells transfected with the human GLP-1 receptor but was without effect on HEK293 cells transfected with the human glucagon receptor. Conversely, zfGIP, but not human GIP, significantly stimulated insulin release from CRISPR/Cas9-engineered INS-1 clonal β-cells from which the GIP receptor had been deleted. Intraperitoneal administration of zfGIP (25 and 75nmol/kg body weight) to mice together with an intraperitoneal glucose load (18mmol/kg body weight) produced a significant decrease in plasma glucose concentrations concomitant with an increase in insulin concentrations. The study provides evidence that the insulinotropic action of zfGIP in mammalian systems involves activation of both the GLP-1 and the GIP receptors but not the glucagon receptor.
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Affiliation(s)
- Galyna V Graham
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland BT52 1SA, UK
| | - J Michael Conlon
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland BT52 1SA, UK.
| | - Yasser H Abdel-Wahab
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland BT52 1SA, UK
| | - Victor A Gault
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland BT52 1SA, UK
| | - Peter R Flatt
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, Ulster University, Cromore Road, Coleraine, Northern Ireland BT52 1SA, UK
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13
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O'Harte FPM, Parthsarathy V, Hogg C, Flatt PR. Apelin-13 analogues show potent in vitro and in vivo insulinotropic and glucose lowering actions. Peptides 2018; 100:219-228. [PMID: 29412822 DOI: 10.1016/j.peptides.2017.12.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 12/01/2017] [Accepted: 12/04/2017] [Indexed: 01/08/2023]
Abstract
Nine structurally modified apelin-13 analogues were assessed for their in vitro and acute in vivo antidiabetic potential. Stability was assessed in mouse plasma and insulinotropic efficacy tested in cultured pancreatic BRIN-BD11 cells and isolated mouse pancreatic islets. Intracellular Ca2+ and cAMP production in BRIN-BD11 cells was determined, as was glucose uptake in 3T3-L1 adipocytes. Acute antihyperglycemic effects of apelin analogues were assessed following i.p. glucose tolerance tests (ipGGT, 18 mmol/kg) in normal and diet-induced-obese (DIO) mice and on food intake in normal mice. Apelin analogues all showed enhanced in vitro stability (up to 5.8-fold, t½ = 12.8 h) in mouse plasma compared to native apelin-13 (t½ = 2.1 h). Compared to glucose controls, stable analogues exhibited enhanced insulinotropic responses from BRIN-BD11 cells (up to 4.7-fold, p < 0.001) and isolated mouse islets (up to 5.3-fold) for 10-7 M apelin-13 amide (versus 7.6-fold for 10-7 M GLP-1). Activation of APJ receptors on BRIN-BD11 cells increased intracellular Ca2+ (up to 3.0-fold, p < 0.001) and cAMP (up to 1.7-fold, p < 0.01). Acute ipGTT showed improved insulinotropic and glucose disposal responses in normal and DIO mice (p < 0.05 and p < 0.01, respectively). Apelin-13 amide and (pGlu)apelin-13 amide were the most effective analogues exhibiting acute, dose-dependent and persistent biological actions. Both analogues stimulated insulin-independent glucose uptake by differentiated adipocytes (2.9-3.3-fold, p < 0.05) and inhibited food intake (26-33%, p < 0.001), up to 180 min in mice, versus saline. In contrast, (Ala13)apelin-13 and (Val13)apelin-13 inhibited insulin secretion, suppressed beta-cell signal transduction and stimulated food intake in mice. Thus, stable analogues of apelin-13 have potential for diabetes/obesity therapy.
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Affiliation(s)
- F P M O'Harte
- The SAAD Centre for Pharmacy & Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK.
| | - V Parthsarathy
- The SAAD Centre for Pharmacy & Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK
| | - C Hogg
- The SAAD Centre for Pharmacy & Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK
| | - P R Flatt
- The SAAD Centre for Pharmacy & Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine, BT52 1SA, Northern Ireland, UK
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14
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Pathak NM, Millar PJB, Pathak V, Flatt PR, Gault VA. Beneficial metabolic effects of dietary epigallocatechin gallate alone and in combination with exendin-4 in high fat diabetic mice. Mol Cell Endocrinol 2018; 460:200-208. [PMID: 28754350 DOI: 10.1016/j.mce.2017.07.024] [Citation(s) in RCA: 7] [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: 02/10/2017] [Revised: 07/24/2017] [Accepted: 07/24/2017] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Significant attempts are being made to generate multifunctional, hybrid or peptide combinations as novel therapeutic strategies for type 2 diabetes, however this presents key challenges including design and pharmaceutical development. In this study, we evaluated metabolic properties of oral nutritional supplement epigallocatechin gallate (EGCG) in combination with GLP-1 agonist exendin-4 in a mouse model of dietary-induced diabetes and obesity. METHODS EGCG, exendin-4 or combination of both were administered twice-daily over 28 days to high fat (HF) mice on background of low-dose streptozotocin. Energy intake, body weight, fat mass, glucose tolerance, insulin sensitivity, lipid profile, biochemical and hormone markers, and islet histology were examined. RESULTS All treatment groups exhibited significantly reduced body weight, fat mass, circulating glucose and insulin concentrations, and HbA1c levels which were independent of changes in energy intake. Similarly, there was marked improvement in glycaemic control, glucose-stimulated insulin release, insulin sensitivity, total cholesterol and triglycerides, with most prominent effects observed following combination therapy. Circulating corticosterone concentrations and 11beta-hydroxysteroid dehydrogenase type1 (11β-HSD1) staining (in pancreas) were beneficially decreased without changes in circulating interleukin 6 (IL-6), alanine transaminase (ALT) and glutathione reductase. Combination therapy resulted in increased islet area and number, beta cell area, and pancreatic insulin content. Generally, metabolic effects were much more pronounced in mice which received combination therapy. CONCLUSIONS EGCG alone and particularly in combination with exendin-4 exerts positive metabolic properties in HF mice. EGCG may be useful dietary adjunct alongside GLP-1 mimetics in treatment of diabetes and related disorders.
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Affiliation(s)
- Nupur M Pathak
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Paul J B Millar
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Varun Pathak
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Peter R Flatt
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, United Kingdom
| | - Victor A Gault
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, United Kingdom.
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15
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Evers A, Haack T, Lorenz M, Bossart M, Elvert R, Henkel B, Stengelin S, Kurz M, Glien M, Dudda A, Lorenz K, Kadereit D, Wagner M. Design of Novel Exendin-Based Dual Glucagon-like Peptide 1 (GLP-1)/Glucagon Receptor Agonists. J Med Chem 2017; 60:4293-4303. [DOI: 10.1021/acs.jmedchem.7b00174] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Andreas Evers
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Torsten Haack
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Martin Lorenz
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Martin Bossart
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Ralf Elvert
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Bernd Henkel
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Siegfried Stengelin
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Michael Kurz
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Maike Glien
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Angela Dudda
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Katrin Lorenz
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Dieter Kadereit
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
| | - Michael Wagner
- R&D, Sanofi-Aventis Deutschland GmbH, Industriepark Höchst Building G838, D-65926 Frankfurt am Main, Germany
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16
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Development of novel ligands for peptide GPCRs. Curr Opin Pharmacol 2016; 31:57-62. [DOI: 10.1016/j.coph.2016.08.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 08/02/2016] [Accepted: 08/12/2016] [Indexed: 12/11/2022]
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17
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O'Harte FPM, Ng MT, Lynch AM, Conlon JM, Flatt PR. Dogfish glucagon analogues counter hyperglycaemia and enhance both insulin secretion and action in diet-induced obese diabetic mice. Diabetes Obes Metab 2016; 18:1013-24. [PMID: 27357054 DOI: 10.1111/dom.12713] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 06/16/2016] [Accepted: 06/23/2016] [Indexed: 12/11/2022]
Abstract
AIMS To investigate the antidiabetic actions of three dogfish glucagon peptide analogues [known glucagon-like peptide-1 and glucagon receptor co-agonists] after chronic administration in diet-induced high-fat-diet-fed diabetic mice. MATERIALS AND METHODS National Institutes of Health Swiss mice were pre-conditioned to a high-fat diet (45% fat) for 100 days, and control mice were fed a normal diet (10% fat). Normal diet control and high-fat-fed control mice received twice-daily intraperitoneal (i.p.) saline injections, while the high-fat-fed treatment groups (n = 8) received twice-daily injections of exendin-4(1-39), [S2a]dogfish glucagon, [S2a]dogfish glucagon exendin-4(31-39) or [S2a]dogfish glucagon-Lys(30) -γ-glutamyl-PAL (25 nmol/kg body weight) for 51 days. RESULTS After dogfish glucagon analogue treatment, there was a rapid and sustained decrease in non-fasting blood glucose and an associated insulinotropic effect (analysis of variance, p < .05 to <.001) compared with saline-treated high-fat-fed controls. All peptide treatments significantly improved i.p. and oral glucose tolerance with concomitant increased insulin secretion compared with saline-treated high-fat-fed controls (p <.05 to <.001). After chronic treatment, no receptor desensitization was observed but insulin sensitivity was enhanced for all peptide-treated groups (p < .01 to <.001) except [S2a]dogfish glucagon. Both exendin-4 and [S2a]dogfish glucagon exendin-4(31-39) significantly reduced plasma triglyceride concentrations compared with those found in lean controls (p = .0105 and p = .0048, respectively). Pancreatic insulin content was not affected by peptide treatments but [S2a]dogfish glucagon and [S2a]dogfish glucagon exendin-4(31-39) decreased pancreatic glucagon by 28%-34% (p = .0221 and p = .0075, respectively). The percentage of β-cell area within islets was increased by exendin-4 and peptide analogue treatment groups compared with high-fat-fed controls and the β-cell area decreased (p < .05 to <.01). CONCLUSIONS Overall, dogfish glucagon co-agonist analogues had several beneficial metabolic effects, showing therapeutic potential for type 2 diabetes.
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Affiliation(s)
- F P M O'Harte
- School of Biomedical Sciences, Saad Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK.
| | - M T Ng
- School of Biomedical Sciences, Saad Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
| | - A M Lynch
- School of Biomedical Sciences, Saad Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
| | - J M Conlon
- School of Biomedical Sciences, Saad Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
| | - P R Flatt
- School of Biomedical Sciences, Saad Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
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