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Tanday N, Zhu W, Tarasov AI, Flatt PR, Irwin N. [P 3]PP, a stable, long-acting pancreatic polypeptide analogue, evokes weight lowering and pancreatic beta-cell-protective effects in obesity-associated diabetes. Diabetes Obes Metab 2024; 26:4945-4957. [PMID: 39192525 DOI: 10.1111/dom.15897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Revised: 08/07/2024] [Accepted: 08/07/2024] [Indexed: 08/29/2024]
Abstract
AIM To thoroughly investigate the impact of sustained neuropeptide Y4 receptor (NPY4R) activation in obesity-associated diabetes. METHODS Initially, the prolonged pharmacodynamic profile of the enzymatically stable pancreatic polypeptide (PP) analogue, [P3]PP, was confirmed in normal mice up to 24 h after injection. Subsequent to this, [P3]PP was administered twice daily (25 nmol/kg) for 28 days to high-fat-fed mice with streptozotocin-induced insulin deficiency, known as HFF/STZ mice. RESULTS Treatment with [P3]PP for 28 days reduced energy intake and was associated with notable weight loss. In addition, circulating glucose was returned to values of approximately 8 mmol/L in [P3]PP-treated mice, with significantly increased plasma insulin and decreased glucagon concentrations. Glucose tolerance and glucose-stimulated insulin secretion were improved in [P3]PP-treated HFF/STZ mice, with no obvious effect on peripheral insulin sensitivity. Benefits on insulin secretion were associated with elevated pancreatic insulin content as well as islet and beta-cell areas. Positive effects on islet architecture were linked to increased beta-cell proliferation and decreased apoptosis. Treatment intervention also decreased islet alpha-cell area, but pancreatic glucagon content remained unaffected. In addition, [P3]PP-treated HFF/STZ mice presented with reduced plasma alanine transaminase and aspartate transaminase levels, with no change in circulating amylase concentrations. In terms of plasma lipid profile, triglyceride and cholesterol levels were significantly decreased by [P3]PP treatment, when compared to saline controls. CONCLUSION Collectively, these data highlight for the first time the potential of enzymatically stable PP analogues for the treatment of obesity and related diabetes.
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Affiliation(s)
- Neil Tanday
- Diabetes Research Centre, Ulster University, Coleraine, UK
| | - Wuyun Zhu
- Diabetes Research Centre, Ulster University, Coleraine, UK
| | | | - Peter R Flatt
- Diabetes Research Centre, Ulster University, Coleraine, UK
| | - Nigel Irwin
- Diabetes Research Centre, Ulster University, Coleraine, UK
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2
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Das S, Ravi H, Babu A, Banerjee M, Kanagavalli R, Dhanasekaran S, Devi Rajeswari V, Venkatraman G, Ramanathan G. Therapeutic potentials of glucose-dependent insulinotropic polypeptide (GIP) in T2DM: Past, present, and future. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2024; 142:293-328. [PMID: 39059989 DOI: 10.1016/bs.apcsb.2023.12.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Type 2 diabetes mellitus (T2DM) is a worldwide health problem that has raised major concerns to the public health community. This chronic condition typically results from the cell's inability to respond to normal insulin levels. Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) are the primary incretin hormones secreted from the intestinal tract. While clinical research has extensively explored the therapeutic potential of GLP-1R in addressing various T2DM-related abnormalities, the possibility of GIPR playing an important role in T2DM treatment is still under investigation. Evidence suggests that GIP is involved in the pathophysiology of T2DM. This chapter focuses on examining the role of GIP as a therapeutic molecule in combating T2DM, comparing the past, present, and future scenarios. Our goal is to delve into how GIP may impact pancreatic β-cell function, adipose tissue uptake, and lipid metabolism. Furthermore, we will elucidate the mechanistic functions of GIP and its receptors in relation to other clinical conditions like cardiovascular diseases, non-alcoholic fatty liver diseases, neurodegenerative diseases, and renal disorders. Additionally, this chapter will shed light on the latest advancements in pharmacological management for T2DM, highlighting potential structural modifications of GIP and the repurposing of drugs, while also addressing the challenges involved in bringing GIP-based treatments into clinical practice.
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Affiliation(s)
- Soumik Das
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Harini Ravi
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Achsha Babu
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Manosi Banerjee
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - R Kanagavalli
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Sivaraman Dhanasekaran
- School of Energy Technology, Pandit Deendayal Energy University, Knowledge Corridor, Gandhinagar, Gujarat, India
| | - V Devi Rajeswari
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Ganesh Venkatraman
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India
| | - Gnanasambandan Ramanathan
- Department of Bio-Medical Sciences, School of Bio Sciences and Technology, Vellore Institute of Technology (VIT), Vellore, Tamil Nadu, India.
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Zhu W, Tanday N, Lafferty RA, Flatt PR, Irwin N. Novel enzyme-resistant pancreatic polypeptide analogs evoke pancreatic beta-cell rest, enhance islet cell turnover, and inhibit food intake in mice. Biofactors 2024. [PMID: 38635341 DOI: 10.1002/biof.2059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 04/02/2024] [Indexed: 04/20/2024]
Abstract
Pancreatic polypeptide (PP) is a postprandial hormone secreted from pancreatic islets that activates neuropeptide Y4 receptors (NPY4Rs). PP is known to induce satiety but effects at the level of the endocrine pancreas are less well characterized. In addition, rapid metabolism of PP by dipeptidyl peptidase-4 (DPP-4) limits the investigation of the effects of the native peptide. Therefore, in the present study, five novel amino acid substituted and/or fatty acid derivatized PP analogs were synthesized, namely [P3]PP, [K13Pal]PP, [P3,K13Pal]PP, [N-Pal]PP, and [N-Pal,P3]PP, and their impact on pancreatic beta-cell function, as well as appetite regulation and glucose homeostasis investigated. All PP analogs displayed increased resistance to DPP-4 degradation. In addition, all peptides inhibited alanine-induced insulin secretion from BRIN-BD11 beta cells. Native PP and related analogs (10-8 and 10-6 M), and especially [P3]PP and [K13Pal]PP, significantly protected against cytokine-induced beta-cell apoptosis and promoted cellular proliferation, with effects dependent on the NPY4R for all peptides barring [N-Pal,P3]PP. In mice, all peptides, except [N-Pal]PP and [N-Pal,P3]PP, evoked a dose-dependent (25, 75, and 200 nmol/kg) suppression of appetite, with native PP and [P3]PP further augmenting glucagon-like peptide-1 (GLP-1) and cholecystokinin (CCK) induced reductions of food intake. The PP peptides had no obvious detrimental effect on glucose tolerance and they did not noticeably impair the glucose-regulatory actions of GLP-1 or CCK. In conclusion, Pro3 amino acid substitution of PP, either alone or together with mid-chain acylation, creates PP analogs with benefits on beta-cell rest, islet cell turnover, and energy regulation that may be applicable to the treatment of diabetes and obesity.
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Affiliation(s)
- Wuyun Zhu
- Diabetes Research Centre, Schools of Biomedical Sciences and Pharmacy & Pharmaceutical Sciences, Ulster University, Coleraine, UK
| | - Neil Tanday
- Diabetes Research Centre, Schools of Biomedical Sciences and Pharmacy & Pharmaceutical Sciences, Ulster University, Coleraine, UK
| | - Ryan A Lafferty
- Diabetes Research Centre, Schools of Biomedical Sciences and Pharmacy & Pharmaceutical Sciences, Ulster University, Coleraine, UK
| | - Peter R Flatt
- Diabetes Research Centre, Schools of Biomedical Sciences and Pharmacy & Pharmaceutical Sciences, Ulster University, Coleraine, UK
| | - Nigel Irwin
- Diabetes Research Centre, Schools of Biomedical Sciences and Pharmacy & Pharmaceutical Sciences, Ulster University, Coleraine, UK
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4
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Coulter-Parkhill A, Gault VA, McClean S, Irwin N. Peptides originally derived from Chilobrachys jingzhao tarantula venom possess beneficial effects on pancreatic beta cell health and function. Eur J Pharmacol 2023:175855. [PMID: 37391009 DOI: 10.1016/j.ejphar.2023.175855] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/12/2023] [Accepted: 06/12/2023] [Indexed: 07/02/2023]
Abstract
Clinical approval of the glucagon-like peptide-1 (GLP-1) mimetic exenatide for the treatment of type 2 diabetes highlights the therapeutic effectiveness of venom-derived peptides. In the present study, we examined and characterised the glucose-lowering potential of synthetic Jingzhaotoxin IX and Jingzhaotoxin XI peptides, which were originally isolated from the venom of the Chinese earth tarantula Chilobrachys jingzhao. Following confirmation of lack of beta-cell toxicity of synthetic peptides, assessment of enzymatic stability and effects on in vitro beta-cell function were studied, alongside putative mechanisms. Glucose homeostatic and appetite suppressive actions of Jingzhaotoxin IX and Jingzhaotoxin XI alone, or in combination with exenatide, were then assessed in normal overnight fasted C57BL/6 mice. Synthetic Jingzhaotoxin peptides were non-toxic and exhibited a decrease in mass of 6 Da in Krebs-Ringer bicarbonate buffer suggesting inhibitor cysteine knot (ICK)-like formation, but interestingly were liable to plasma enzyme degradation. The Jingzhaotoxin peptides evoked prominent insulin secretion from BRIN BD11 beta-cells, with activity somewhat characteristic of Kv2.1 channel binding. In addition, Jingzhaotoxin peptides enhanced beta-cell proliferation and provided significant protection against cytokine-induced apoptosis. When injected co-jointly with glucose, the Jingzhaotoxin peptides slightly decreased blood-glucose levels but had no effect on appetite in overnight fasted mice. Whilst the Jingzhaotoxin peptides did not enhance exenatide-induced benefits on glucose homeostasis, they augmented exenatide-mediated suppression of appetite. Taken together, these data highlight the therapeutic potential of tarantula venom-derived peptides, such as Jingzhaotoxin IX and Jingzhaotoxin XI either alone or in combination with exenatide, for diabetes and related obesity.
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Affiliation(s)
- A Coulter-Parkhill
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, UK
| | - V A Gault
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, UK
| | - S McClean
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, UK
| | - N Irwin
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, UK.
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5
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Lafferty RA, Flatt PR, Irwin N. GLP-1/GIP analogues: potential impact in the landscape of obesity pharmacotherapy. Expert Opin Pharmacother 2023; 24:587-597. [PMID: 36927378 DOI: 10.1080/14656566.2023.2192865] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
INTRODUCTION : Obesity is recognised as a major healthcare challenge. Following years of slow progress in discovery of safe, effective therapies for weight management, recent approval of the glucagon-like peptide 1 receptor (GLP-1R) mimetics, liraglutide and semaglutide, for obesity has generated considerable excitement. It is anticipated these agents will pave the way for application of tirzepatide, a highly effective glucose-dependent insulinotropic polypeptide receptor (GIPR), GLP-1R co-agonist recently approved for management of type 2 diabetes mellitus. AREAS COVERED : Following promising weight loss in obese individuals in Phase III clinical trials, liraglutide and semaglutide were approved for weight management without diabetes. Tirzepatide has attained Fast Track designation for obesity management by the US Food and Drug Association. This narrative review summarises experimental, preclinical and clinical data for these agents and related GLP-1R/GIPR co-agonists, prioritising clinical research published within the last 10 years where possible. EXPERT OPINION : GLP-1R mimetics are often discontinued within 24-months, owing to gastrointestinal side-effects, meaning long-term application of these agents in obesity is questioned. Combined GIPR/GLP-1R agonism appears to induce fewer side-effects, indicating GLP-1R/GIPR co-agonists may be more suitable for enduring obesity management. After years of debate, this GIPR-biased GLP-1R/GIPR co-agonist highlights the therapeutic promise of including GIPR modulation for diabetes and obesity therapy.
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Affiliation(s)
- Ryan A Lafferty
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, BT52 1SA, UK
| | - Peter R Flatt
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, BT52 1SA, UK
| | - Nigel Irwin
- Diabetes Research Centre, Ulster University, Coleraine, Northern Ireland, BT52 1SA, UK
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6
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Malviya R, Verma S, Sundram S. Advancement and Strategies for the Development of Peptide-Drug Conjugates: Pharmacokinetic Modulation, Role and Clinical Evidence Against Cancer Management. Curr Cancer Drug Targets 2021; 22:286-311. [PMID: 34792003 DOI: 10.2174/1568009621666211118111506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/29/2021] [Accepted: 09/09/2021] [Indexed: 12/24/2022]
Abstract
Currently, many new treatment strategies are being used for the management of cancer. Among them, chemotherapy based on peptides has been of great interest due to the unique features of peptides. This review discusses the role of peptide and peptides analogues in the treatment of cancer, with special emphasis on their pharmacokinetic modulation and research progress. Low molecular weight, targeted drug delivery, enhanced permeability, etc., of the peptide-linked drug conjugates, lead to an increase in the effectiveness of cancer therapy. Various peptides have recently been developed as drugs and vaccines with an altered pharmacokinetic parameter which has subsequently been assessed in different phases of the clinical study. Peptides have made a great impact in the area of cancer therapy and diagnosis. Targeted chemotherapy and drug delivery techniques using peptides are emerging as excellent tools in minimizing problems with conventional chemotherapy. It can be concluded that new advances in using peptides to treat different types of cancer have been shown by different clinical studies indicating that peptides could be used as an ideal therapeutic method in treating cancer due to the novel advantages of peptides. The development of identifying and synthesizing novel peptides could provide a promising choice to patients with cancer.
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Affiliation(s)
- Rishabha Malviya
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida. India
| | - Swati Verma
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida. India
| | - Sonali Sundram
- Department of Pharmacy, School of Medical and Allied Sciences, Galgotias University, Greater Noida. India
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7
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Dodt K, Lamer S, Drießen M, Bölch S, Schlosser A, Lühmann T, Meinel L. Mass-Encoded Reporters Reporting Proteolytic Activity from within the Extracellular Matrix. ACS Biomater Sci Eng 2020; 6:5240-5253. [PMID: 33455273 DOI: 10.1021/acsbiomaterials.0c00691] [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] [Indexed: 12/12/2022]
Abstract
Reporting matrix metalloproteinase (MMP) activity directly from the extracellular matrix (ECM) may provide critical insights to better characterize 2D and 3D cell culture model systems of inflammatory diseases and potentially leverage in vivo diagnosis. In this proof-of-concept study, we designed MMP-sensors, which were covalently linked onto the ECM by co-administration of the activated transglutaminase factor XIIIa (FXIIIa). Elements of the featured MMP-sensors are the D-domain of insulin-like growth factor I (IGF-I) through which co-administered FXIIIa covalently links the sensor to the ECM followed by an MMP sensitive peptide sequence and locally reporting on MMP activity, an isotopically labeled mass tag encoding for protease activity, and an affinity tag facilitating purification from fluids. All sensors come in identical pairs, other than the MMP sensitive peptide sequence, which is synthesized with l-amino acids or d-amino acids, the latter serving as internal standard. As a proof of concept for multiplexing, we successfully profiled two MMP-sensors with different MMP sensitive peptide sequences reporting MMP activity directly from an engineered 3D ECM. Future use may include covalently ECM bound diagnostic depots reporting MMP activity from inflamed tissues.
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Affiliation(s)
- Katharina Dodt
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Stephanie Lamer
- Rudolf-Virchow-Center for Experimental Biomedicine, University of Wuerzburg, Josef-Schneider-Str. 2, 97080 Wuerzburg, Germany
| | - Marc Drießen
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Sebastian Bölch
- Department for Orthopedic Surgery, Koenig-Ludwig-Haus, University of Wuerzburg, Brettreichstrasse 11, 97074 Wuerzburg, Germany
| | - Andreas Schlosser
- Rudolf-Virchow-Center for Experimental Biomedicine, University of Wuerzburg, Josef-Schneider-Str. 2, 97080 Wuerzburg, Germany
| | - Tessa Lühmann
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Lorenz Meinel
- Institute of Pharmacy and Food Chemistry, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
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8
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Lafferty RA, Gault VA, Flatt PR, Irwin N. Effects of 2 Novel PYY(1-36) Analogues, (P 3L 31P 34)PYY(1-36) and PYY(1-36)(Lys 12PAL), on Pancreatic Beta-Cell Function, Growth, and Survival. CLINICAL MEDICINE INSIGHTS-ENDOCRINOLOGY AND DIABETES 2019; 12:1179551419855626. [PMID: 31244528 PMCID: PMC6580715 DOI: 10.1177/1179551419855626] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 05/15/2019] [Indexed: 12/14/2022]
Abstract
Recent studies have identified a beneficial role for peptide tyrosine tyrosine
(PYY) on pancreatic beta-cell function and survival. These effects are linked to
the activation of neuropeptide Y1 receptors (NPYR1s) by PYY(1-36). However,
PYY(1-36) is subject to rapid degradation by dipeptidyl peptidase-4 (DPP-4),
resulting is the loss of NPYR1 activity. Therefore, the aim of this study was to
develop 2 enzymatically stable PYY(1-36) analogues, namely,
(P3L31P34)PYY(1-36) and
PYY(1-36)(Lys12PAL), with further structural modifications to
enhance NPYR1 specificity. As expected,
(P3L31P34)PYY(1-36) was fully resistant to
DPP-4-mediated degradation in vitro, whereas PYY(1-36) and
PYY(1-36)(Lys12PAL) were both liable to DPP-4 breakdown.
PYY(1-36) and (P3L31P34)PYY(1-36) induced
significant reductions in glucose-stimulated insulin secretion (GSIS) from BRIN
BD11 cells, but only PYY(1-36) diminished alanine-stimulated insulin secretion.
In contrast, PYY(1-36)(Lys12PAL) had no impact on GSIS or
alanine-induced insulin release. All 3 PYY peptides significantly enhanced
proliferation in BRIN BD11 and 1.1B4 beta-cell lines, albeit only at the highest
concentration examined, 10-6 M, for
(P3L31P34)PYY(1-36) and
PYY(1-36)(Lys12PAL) in BRIN BD11 cells. Regarding the protection
of beta-cells against cytokine-induced apoptosis, PYY(1-36) induced clear
protective effects. Both (P3L31P34)PYY(1-36)
and PYY(1-36)(Lys12PAL) offered some protection against apoptosis in
BRIN BD11 cells, but were significantly less efficacious than PYY(1-36).
Similarly, in 1.1B4 cells, both PYY analogues (10-6 M) protected
against cytokine-induced apoptosis, but
(P3L31P34)PYY(1-36) was significantly less
effective than PYY(1-36). All 3 PYY peptides had no impact on refeeding in
overnight fasted mice. These data underline the beta-cell benefits of PYY(1-36)
and highlight the challenges of synthesising stable, bioactive, NPYR1-specific,
PYY(1-36) analogues.
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Affiliation(s)
- Ryan A Lafferty
- SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK.,Diabetes Research Group, University of Ulster, Coleraine, UK
| | - Victor A Gault
- SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
| | - Peter R Flatt
- SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
| | - Nigel Irwin
- SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, UK
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Hutchinson JA, Hamley IW, Torras J, Alemán C, Seitsonen J, Ruokolainen J. Self-Assembly of Lipopeptides Containing Short Peptide Fragments Derived from the Gastrointestinal Hormone PYY 3-36: From Micelles to Amyloid Fibrils. J Phys Chem B 2019; 123:614-621. [PMID: 30609361 PMCID: PMC7005981 DOI: 10.1021/acs.jpcb.8b11097] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
We
investigate the impact of lipidation on the self-assembly of
two peptide fragments from the gastrointestinal peptide hormone PYY3–36. The lipopeptides C16IKPEAP and C16IKPEAPGE contain the first 6 and 8 amino acid residues, respectively,
from the PYY3–36 peptide sequence, with a palmitoyl
C16 tail attached at the N-terminus. These lipopeptides
form spherical micelles in aqueous solution, above a critical micelle
concentration (cmc), which is pH-dependent. Modeling of small-angle
X-ray scattering data along with molecular dynamics simulations shows
the formation of micelles with a hydrophobic interior and a well-hydrated
exterior. The lipopeptides have a disordered conformation over the
pH and temperature ranges studied. The cmc is found to be independent
of temperature, pointing to athermal micellization. In contrast to
the presence of hydrated micelles in solution, β-sheet amyloid
fibrils form in dried samples. Thus, the nanostructure of lipidated
PYY3–36 fragment peptides can be tuned by control
of pH or concentration, for future applications.
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Affiliation(s)
- Jessica A Hutchinson
- Department of Chemistry , University of Reading , Whiteknights , Reading RG6 6AD , United Kingdom
| | - Ian W Hamley
- Department of Chemistry , University of Reading , Whiteknights , Reading RG6 6AD , United Kingdom
| | - Juan Torras
- Department of Chemical Engineering and Barcelona Research Center for Multiscale Science and Engineering , Universitat Politècnica de Catalunya, Escola d'Enginyeria de Barcelona Est (EEBE) Campus Diagonal Besòs , C/Eduard Maristany 10-14 , 08019 Barcelona , Spain
| | - Carlos Alemán
- Department of Chemical Engineering and Barcelona Research Center for Multiscale Science and Engineering , Universitat Politècnica de Catalunya, Escola d'Enginyeria de Barcelona Est (EEBE) Campus Diagonal Besòs , C/Eduard Maristany 10-14 , 08019 Barcelona , Spain
| | - Jani Seitsonen
- Nanomicroscopy Center , Aalto University , Puumiehenkuja 2 , FIN-02150 Espoo , Finland
| | - Janne Ruokolainen
- Nanomicroscopy Center , Aalto University , Puumiehenkuja 2 , FIN-02150 Espoo , Finland
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Verma MK, Goel R, Krishnadas N, Nemmani KVS. Targeting glucose-dependent insulinotropic polypeptide receptor for neurodegenerative disorders. Expert Opin Ther Targets 2018; 22:615-628. [PMID: 29911915 DOI: 10.1080/14728222.2018.1487952] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
INTRODUCTION Incretin hormones, glucose-dependent insulinotropic polypeptide (GIP), and glucagon-like peptide-1 (GLP-1) exert pleiotropic effects on endocrine pancreas and nervous system. Expression of GIP and GIP receptor (GIPR) in neurons, their roles in neurogenesis, synaptic plasticity, neurotransmission, and neuromodulation uniquely position GIPR for therapeutic applications in neurodegenerative disorders. GIP analogs acting as GIPR agonists attenuate neurobehavioral and neuropathological sequelae of neurodegenerative disorders in preclinical models, e.g. Alzheimer's disease (AD), Parkinson's disease (PD), and cerebrovascular disorders. Modulation of GIPR signaling offers an unprecedented approach for disease modification by arresting neuronal viability decline, enabling neuronal regeneration, and reducing neuroinflammation. Growth-promoting effects of GIP signaling and broad-based neuroprotection highlight the therapeutic potential of GIPR agonists. Areas covered: This review focuses on the role of GIPR-mediated signaling in the central nervous system in neurophysiological and neuropathological conditions. In context of neurodegeneration, the article summarizes potential of targeting GIPR signaling for neurodegenerative conditions such as AD, PD, traumatic brain injury, and cerebrovascular disorders. Expert opinion: GIPR represents a validated therapeutic target for neurodegenerative disorders. GIPR agonists impart symptomatic improvements, slowed neurodegeneration, and enhanced neuronal regenerative capacity in preclinical models. Modulation of GIPR signaling is potentially a viable therapeutic approach for disease modification in neurodegenerative disorders.
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Affiliation(s)
- Mahip K Verma
- a Department of Pharmacology, Novel Drug Discovery and Development , Lupin Limited , Pune , India
| | - Rajan Goel
- a Department of Pharmacology, Novel Drug Discovery and Development , Lupin Limited , Pune , India
| | - Nandakumar Krishnadas
- b Department of Pharmacology , Manipal College of Pharmaceutical Sciences, Manipal Academy of Higher Education (MAHE) , Manipal , India
| | - Kumar V S Nemmani
- a Department of Pharmacology, Novel Drug Discovery and Development , Lupin Limited , Pune , India
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Parthsarathy V, Hogg C, Flatt PR, O'Harte FPM. Beneficial long-term antidiabetic actions of N- and C-terminally modified analogues of apelin-13 in diet-induced obese diabetic mice. Diabetes Obes Metab 2018; 20:319-327. [PMID: 28730728 DOI: 10.1111/dom.13068] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 07/14/2017] [Accepted: 07/17/2017] [Indexed: 12/12/2022]
Abstract
AIMS To investigate the chronic effects of twice-daily administration of stable apelin analogues, apelin-13 amide and pyroglutamyl (pGlu) apelin-13 amide, on metabolic variables in glucose-intolerant and insulin-resistant diet-induced obese mice fed a high-fat diet for 150 days. METHODS Groups of mice received twice-daily (9 am and 5 pm) injections of saline vehicle, apelin-13 amide, (pGlu)apelin-13 amide or exendin-4(1-39) for 28 days (all at 25 nmol/kg). Energy intake, body weight, non-fasting blood glucose, plasma insulin, glucose tolerance, metabolic response to feeding and insulin sensitivity, together with pancreatic hormone content and biochemical variables such as lipids and total GLP-1 were monitored. Dual-energy X-ray absorptiometry analysis and indirect calorimetry were also performed. RESULTS Administration of apelin-13 amide, (pGlu)apelin-13 amide or exendin-4 significantly decreased body weight, food intake and blood glucose and increased plasma insulin compared with high-fat-fed saline-treated controls (P < .05 and P < .001), Additionally, all peptide-treated groups exhibited improved glucose tolerance (oral and intraperitoneal), metabolic responses to feeding and associated insulin secretion. (pGlu)apelin-13 amide also significantly improved glycated haemoglobin and insulin sensitivity after 28 days. Both (pGlu)apelin-13 amide and exendin-4 increased bone mineral content and decreased respiratory exchange ratio, whereas only (pGlu)apelin-13 amide increased energy expenditure. All treatment groups displayed reduced circulating triglycerides and increased glucagon-like peptide-1 concentrations, although only (pGlu)apelin-13 amide significantly reduced LDL cholesterol and total body fat, and increased pancreatic insulin content. CONCLUSION These data indicate the therapeutic potential of stable apelin-13 analogues, with effects equivalent to or better than those of exendin-4.
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Affiliation(s)
- Vadivel Parthsarathy
- School of Biomedical Sciences, SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, Northern Ireland, UK
| | - Christopher Hogg
- School of Biomedical Sciences, SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, Northern Ireland, UK
| | - Peter R Flatt
- School of Biomedical Sciences, SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, Northern Ireland, UK
| | - Finbarr P M O'Harte
- School of Biomedical Sciences, SAAD Centre for Pharmacy and Diabetes, University of Ulster, Coleraine, Northern Ireland, UK
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Brandt SJ, Götz A, Tschöp MH, Müller TD. Gut hormone polyagonists for the treatment of type 2 diabetes. Peptides 2018; 100:190-201. [PMID: 29412819 PMCID: PMC5805859 DOI: 10.1016/j.peptides.2017.12.021] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/21/2017] [Accepted: 12/21/2017] [Indexed: 12/20/2022]
Abstract
Chemical derivatives of the gut-derived peptide hormone glucagon-like peptide 1 (GLP-1) are among the best-in-class pharmacotherapies to treat obesity and type 2 diabetes. However, GLP-1 analogs have modest weight lowering capacity, in the range of 5-10%, and the therapeutic window is hampered by dose-dependent side effects. Over the last few years, a new concept has emerged: combining the beneficial effects of several key metabolic hormones into a single molecular entity. Several unimolecular GLP-1-based polyagonists have shown superior metabolic action compared to GLP-1 monotherapies. In this review article, we highlight the history of polyagonists targeting the receptors for GLP-1, GIP and glucagon, and discuss recent progress in expanding of this concept to now allow targeted delivery of nuclear hormones via GLP-1 and other gut hormones, as a novel approach towards more personalized pharmacotherapies.
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Affiliation(s)
- Sara J Brandt
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany
| | - Anna Götz
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany; Department of Internal Medicine I, University Hospital RWTH Aachen, Aachen, Germany; Institute for Diabetes und Regeneration, Helmholtz Diabetes Center, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748, Garching, Germany
| | - Matthias H Tschöp
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Division of Metabolic Diseases, Department of Medicine, Technische Universität München, Munich, Germany
| | - Timo D Müller
- Institute for Diabetes and Obesity, Helmholtz Diabetes Center at Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Business Campus Garching, Parkring 13, 85748 Garching, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany.
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Li Y, Li L, Hölscher C. Incretin-based therapy for type 2 diabetes mellitus is promising for treating neurodegenerative diseases. Rev Neurosci 2018; 27:689-711. [PMID: 27276528 DOI: 10.1515/revneuro-2016-0018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 05/02/2016] [Indexed: 12/13/2022]
Abstract
Incretin hormones include glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Due to their promising action on insulinotropic secretion and improving insulin resistance (IR), incretin-based therapies have become a new class of antidiabetic agents for the treatment of type 2 diabetes mellitus (T2DM). Recently, the links between neurodegenerative diseases and T2DM have been identified in a number of studies, which suggested that shared mechanisms, such as insulin dysregulation or IR, may underlie these conditions. Therefore, the effects of incretins in neurodegenerative diseases have been extensively investigated. Protease-resistant long-lasting GLP-1 mimetics such as lixisenatide, liraglutide, and exenatide not only have demonstrated promising effects for treating neurodegenerative diseases in preclinical studies but also have shown first positive results in Alzheimer's disease (AD) and Parkinson's disease (PD) patients in clinical trials. Furthermore, the effects of other related incretin-based therapies such as GIP agonists, dipeptidyl peptidase-IV (DPP-IV) inhibitors, oxyntomodulin (OXM), dual GLP-1/GIP, and triple GLP-1/GIP/glucagon receptor agonists on neurodegenerative diseases have been tested in preclinical studies. Incretin-based therapies are a promising approach for treating neurodegenerative diseases.
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Yu YW, Hsieh TH, Chen KY, Wu JCC, Hoffer BJ, Greig NH, Li Y, Lai JH, Chang CF, Lin JW, Chen YH, Yang LY, Chiang YH. Glucose-Dependent Insulinotropic Polypeptide Ameliorates Mild Traumatic Brain Injury-Induced Cognitive and Sensorimotor Deficits and Neuroinflammation in Rats. J Neurotrauma 2016; 33:2044-2054. [PMID: 26972789 PMCID: PMC5116684 DOI: 10.1089/neu.2015.4229] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Mild traumatic brain injury (mTBI) is a major public health issue, representing 75-90% of all cases of TBI. In clinical settings, mTBI, which is defined as a Glascow Coma Scale (GCS) score of 13-15, can lead to various physical, cognitive, emotional, and psychological-related symptoms. To date, there are no pharmaceutical-based therapies to manage the development of the pathological deficits associated with mTBI. In this study, the neurotrophic and neuroprotective properties of glucose-dependent insulinotropic polypeptide (GIP), an incretin similar to glucagon-like peptide-1 (GLP-1), was investigated after its steady-state subcutaneous administration, focusing on behavior after mTBI in an in vivo animal model. The mTBI rat model was generated by a mild controlled cortical impact (mCCI) and used to evaluate the therapeutic potential of GIP. We used the Morris water maze and novel object recognition tests, which are tasks for spatial and recognition memory, respectively, to identify the putative therapeutic effects of GIP on cognitive function. Further, beam walking and the adhesive removal tests were used to evaluate locomotor activity and somatosensory functions in rats with and without GIP administration after mCCI lesion. Lastly, we used immunohistochemical (IHC) staining and Western blot analyses to evaluate the inflammatory markers, glial fibrillary acidic protein (GFAP), amyloid-β precursor protein (APP), and bone marrow tyrosine kinase gene in chromosome X (BMX) in animals with mTBI. GIP was well tolerated and ameliorated mTBI-induced memory impairments, poor balance, and sensorimotor deficits after initiation in the post-injury period. In addition, GIP mitigated mTBI-induced neuroinflammatory changes on GFAP, APP, and BMX protein levels. These findings suggest GIP has significant benefits in managing mTBI-related symptoms and represents a novel strategy for mTBI treatment.
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Affiliation(s)
- Yu-Wen Yu
- 1 PhD Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes , Taipei, Taiwan
| | - Tsung-Hsun Hsieh
- 1 PhD Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes , Taipei, Taiwan .,2 Center for Neurotrauma and Neuroregeneration, Taipei Medical University , Taipei, Taiwan .,3 Department of Physical Therapy and Graduate Institute of Rehabilitation Science, College of Medicine, Chang Gung University , Taoyuan, Taiwan
| | - Kai-Yun Chen
- 1 PhD Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes , Taipei, Taiwan .,2 Center for Neurotrauma and Neuroregeneration, Taipei Medical University , Taipei, Taiwan
| | - John Chung-Che Wu
- 4 Department of Surgery, College of Medicine, Taipei Medical University , Taipei, Taiwan
| | - Barry J Hoffer
- 1 PhD Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes , Taipei, Taiwan .,5 Department of Neurosurgery, Case Western Reserve University , School of Medicine, Cleveland, Ohio
| | - Nigel H Greig
- 6 Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health , Baltimore, Maryland
| | - Yazhou Li
- 6 Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health , Baltimore, Maryland
| | - Jing-Huei Lai
- 2 Center for Neurotrauma and Neuroregeneration, Taipei Medical University , Taipei, Taiwan .,4 Department of Surgery, College of Medicine, Taipei Medical University , Taipei, Taiwan
| | - Cheng-Fu Chang
- 4 Department of Surgery, College of Medicine, Taipei Medical University , Taipei, Taiwan
| | - Jia-Wei Lin
- 4 Department of Surgery, College of Medicine, Taipei Medical University , Taipei, Taiwan
| | - Yu-Hsin Chen
- 7 Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University , Taipei, Taiwan .,8 Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University , Taipei, Taiwan
| | - Liang-Yo Yang
- 7 Department of Physiology, School of Medicine, College of Medicine, Taipei Medical University , Taipei, Taiwan .,9 Research Center for Biomedical Devices and Prototyping Production, Taipei Medical University , Taipei, Taiwan .,11 School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan
| | - Yung-Hsiao Chiang
- 1 PhD Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University and National Health Research Institutes , Taipei, Taiwan .,2 Center for Neurotrauma and Neuroregeneration, Taipei Medical University , Taipei, Taiwan .,4 Department of Surgery, College of Medicine, Taipei Medical University , Taipei, Taiwan .,10 Translational Laboratory, Department of Medical Research, Taipei Medical University Hospital, Taipei, Taiwan
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Finan B, Müller TD, Clemmensen C, Perez-Tilve D, DiMarchi RD, Tschöp MH. Reappraisal of GIP Pharmacology for Metabolic Diseases. Trends Mol Med 2016; 22:359-376. [DOI: 10.1016/j.molmed.2016.03.005] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 03/15/2016] [Accepted: 03/17/2016] [Indexed: 12/31/2022]
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Candeias EM, Sebastião IC, Cardoso SM, Correia SC, Carvalho CI, Plácido AI, Santos MS, Oliveira CR, Moreira PI, Duarte AI. Gut-brain connection: The neuroprotective effects of the anti-diabetic drug liraglutide. World J Diabetes 2015; 6:807-827. [PMID: 26131323 PMCID: PMC4478577 DOI: 10.4239/wjd.v6.i6.807] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 01/30/2015] [Accepted: 05/18/2015] [Indexed: 02/05/2023] Open
Abstract
Long-acting glucagon-like peptide-1 (GLP-1) analogues marketed for type 2 diabetes (T2D) treatment have been showing positive and protective effects in several different tissues, including pancreas, heart or even brain. This gut secreted hormone plays a potent insulinotropic activity and an important role in maintaining glucose homeostasis. Furthermore, growing evidences suggest the occurrence of several commonalities between T2D and neurodegenerative diseases, insulin resistance being pointed as a main cause for cognitive decline and increased risk to develop dementia. In this regard, it has also been suggested that stimulation of brain insulin signaling may have a protective role against cognitive deficits. As GLP-1 receptors (GLP-1R) are expressed throughout the central nervous system and GLP-1 may cross the blood-brain-barrier, an emerging hypothesis suggests that they may be promising therapeutic targets against brain dysfunctional insulin signaling-related pathologies. Importantly, GLP-1 actions depend not only on the direct effect mediated by its receptor activation, but also on the gut-brain axis involving an exchange of signals between both tissues via the vagal nerve, thereby regulating numerous physiological functions (e.g., energy homeostasis, glucose-dependent insulin secretion, as well as appetite and weight control). Amongst the incretin/GLP-1 mimetics class of anti-T2D drugs with an increasingly described neuroprotective potential, the already marketed liraglutide emerged as a GLP-1R agonist highly resistant to dipeptidyl peptidase-4 degradation (thereby having an increased half-life) and whose systemic GLP-1R activity is comparable to that of native GLP-1. Importantly, several preclinical studies showed anti-apoptotic, anti-inflammatory, anti-oxidant and neuroprotective effects of liraglutide against T2D, stroke and Alzheimer disease (AD), whereas several clinical trials, demonstrated some surprising benefits of liraglutide on weight loss, microglia inhibition, behavior and cognition, and in AD biomarkers. Herein, we discuss the GLP-1 action through the gut-brain axis, the hormone’s regulation of some autonomic functions and liraglutide’s neuroprotective potential.
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Martin CM, Irwin N, Flatt PR, Gault VA. A novel acylated form of (d-Ala2)GIP with improved antidiabetic potential, lacking effect on body fat stores. Biochim Biophys Acta Gen Subj 2013; 1830:3407-13. [DOI: 10.1016/j.bbagen.2013.03.011] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/08/2013] [Accepted: 03/08/2013] [Indexed: 10/27/2022]
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Bhat VK, Kerr BD, Vasu S, Flatt PR, Gault VA. A DPP-IV-resistant triple-acting agonist of GIP, GLP-1 and glucagon receptors with potent glucose-lowering and insulinotropic actions in high-fat-fed mice. Diabetologia 2013; 56:1417-24. [PMID: 23503814 DOI: 10.1007/s00125-013-2892-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 03/01/2013] [Indexed: 01/12/2023]
Abstract
AIMS/HYPOTHESIS We designed a chemically modified, enzyme-resistant peptide with triple-acting properties based on human glucagon with amino acid substitutions aligned to strategic positions in the sequence of glucose-dependent insulinotropic polypeptide (GIP). METHODS Y(1)-dA(2)-I(12)-N(17)-V(18)-I(27)-G(28,29)-glucagon (termed YAG-glucagon) was incubated with dipeptidylpeptidase IV (DPP-IV) to assess stability, BRIN-BD11 cells to evaluate insulin secretion, and receptor-transfected cells to examine cAMP production. Acute glucose-lowering and insulinotropic properties of YAG-glucagon were assessed in National Institutes of Health (NIH) Swiss mice, while longer-term actions on glucose homeostasis, insulin secretion, food intake and body weight were examined in high-fat-fed mice. RESULTS YAG-glucagon was resistant to DPP-IV, increased in vitro insulin secretion (1.5-3-fold; p < 0.001) and stimulated cAMP production in GIP receptor-, glucagon-like peptide-1 (GLP-1) receptor- and glucagon receptor-transfected cells. Plasma glucose levels were significantly reduced (by 51%; p < 0.01) and insulin concentrations increased (1.2-fold; p < 0.01) after acute injection of YAG-glucagon in NIH Swiss mice. Acute actions were countered by established GIP, GLP-1 and glucagon antagonists. In high-fat-fed mice, twice-daily administration of YAG-glucagon for 14 days reduced plasma glucose (40% reduction; p < 0.01) and increased plasma insulin concentrations (1.8-fold; p < 0.05). Glycaemic responses were markedly improved (19-48% reduction; p < 0.05) and insulin secretion enhanced (1.5-fold; p < 0.05) after a glucose load, which were independent of changes in insulin sensitivity, food intake and body weight. CONCLUSIONS/INTERPRETATION YAG-glucagon is a DPP-IV-resistant triple agonist of GIP, GLP-1 and glucagon receptors and exhibits beneficial biological properties suggesting that it may hold promise for treatment of type 2 diabetes.
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Affiliation(s)
- V K Bhat
- The SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine, BT52 1SA, Northern Ireland, UK
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Lennox R, Porter DW, Flatt PR, Gault VA. (Val8)GLP-1-Glu-PAL: a GLP-1 Agonist That Improves Hippocampal Neurogenesis, Glucose Homeostasis, and β-Cell Function in High-Fat-Fed Mice. ChemMedChem 2012; 8:595-602. [DOI: 10.1002/cmdc.201200409] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 10/17/2012] [Indexed: 11/10/2022]
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Administration of an acylated GLP-1 and GIP preparation provides added beneficial glucose-lowering and insulinotropic actions over single incretins in mice with Type 2 diabetes and obesity. Clin Sci (Lond) 2011; 121:107-17. [PMID: 21332446 DOI: 10.1042/cs20110006] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The present study examined the glucose-lowering and insulinotropic properties of acylated GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) peptides in Type 2 diabetes and obesity. GLP-1, GIP, Liraglutide, N-AcGIP(Lys(37)Myr) (N-acetylGIP with myristic acid conjugated at Lys(37)), a simple combination of both peptides and a Lira-AcGIP preparation [overnight preparation of Liraglutide and N-AcGIP(Lys(37)Myr)] were incubated with DPP-IV (dipeptidyl peptidase-IV) to assess peptide stability, and BRIN-BD11 cells were used to evaluate cAMP production and insulin secretion. Acute glucose-lowering and insulinotropic actions were evaluated in Swiss TO mice. Subchronic studies on glucose homoeostasis, insulin secretion, food intake and bodyweight were evaluated in ob/ob mice. Liraglutide, N-AcGIP(Lys(37)Myr), a simple combination of both peptides and the Lira-AcGIP preparation demonstrated improved DPP-IV resistance (P<0.001), while stimulating cAMP production and insulin secretion (1.4-2-fold; P<0.001). The Lira-AcGIP preparation was more potent at lowering plasma glucose (20-51% reduction; P<0.05-P<0.001) and stimulating insulin secretion (1.5-1.8-fold; P<0.05-P<0.001) compared with Liraglutide and N-AcGIP(Lys(37)Myr) or a simple peptide combination. Daily administration of the Lira-AcGIP preparation to ob/ob mice lowered bodyweight (7-9%; P<0.05), food intake (23%; P<0.05) and plasma glucose (46% reduction; P<0.001), while increasing plasma insulin (1.5-1.6-fold; P<0.001). The Lira-AcGIP preparation enhanced glucose tolerance, insulin response to glucose and insulin content (P<0.05-P<0.001). These findings demonstrate that a combined preparation of the acylated GLP-1 and GIP peptides Liraglutide and N-AcGIP(Lys(37)Myr) markedly improved glucose-lowering and insulinotropic properties in diabetic obesity compared with either incretin mimetic given individually.
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Franklin ZJ, McDonnell B, Montgomery IA, Flatt PR, Irwin N. Dual modulation of GIP and glucagon action by the low molecular weight compound 4-hydroxybenzoic acid 2-bromobenzylidene hydrazide. Diabetes Obes Metab 2011; 13:742-9. [PMID: 21418501 DOI: 10.1111/j.1463-1326.2011.01401.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM The presence of functional gastric inhibitory polypeptide (GIP) receptors on adipocytes and knowledge that GIP plays a key role in fat deposition suggests a beneficial effect of GIP receptor antagonism in obesity and insulin resistance. GIP receptor antagonists studied to date are peptidic GIP analogues that must be administered by injection. METHODS The present study has examined in vitro and in vivo metabolic actions of a low molecular weight GIP receptor modulator 4-hydroxybenzoic acid 2-bromobenzylidene hydrazide (4H2BH), suitable for oral administration. RESULTS 4H2BH alone had no significant effect on cAMP production or insulin secretion from BRIN-BD11 cells. However, 4H2BH significantly inhibited GIP-mediated cAMP production and insulin secretion in vitro. 4H2BH also suppressed (p < 0.05 to p < 0.001) glucagon-induced elevations of cAMP generation and insulin secretion in BRIN-BD11 cells. However, 4H2BH had no effect on glucagon-like peptide-1 (GLP-1) mediated insulinotropic actions. Administration of 4H2BH to mice in combination with glucose and GIP significantly annulled the glucose-lowering actions of GIP. In agreement with this, 4H2BH completely annulled GIP-mediated insulin secretion. Combined injection of 4H2BH with glucagon also partially (p < 0.05 to p < 0.001) impaired glucagon-induced elevations in blood glucose and plasma insulin. 4H2BH had no effect on blood glucose or insulin levels when administered alone. CONCLUSION These results indicate that 4H2BH has a dual effect of inhibiting GIP and glucagon-mediated biological actions. Given that hyperglucagonaemia is also a cardinal feature of type 2 diabetes, 4H2BH and related low molecular weight compounds appear worthy of further evaluation for therapeutic potential in obesity diabetes.
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Affiliation(s)
- Z J Franklin
- SAAD Centre for Pharmacy and Diabetes, School of Biomedical Sciences, University of Ulster, Coleraine, UK
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Irwin N, Gault V, Flatt PR. Therapeutic potential of the original incretin hormone glucose-dependent insulinotropic polypeptide: diabetes, obesity, osteoporosis and Alzheimer's disease? Expert Opin Investig Drugs 2010; 19:1039-48. [DOI: 10.1517/13543784.2010.513381] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Nigel Irwin
- SAAD Centre for Diabetes and Pharmacy, School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine, Co. Londonderry, BT52 1SA, Northern Ireland, UK ;
| | - Victor Gault
- SAAD Centre for Diabetes and Pharmacy, School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine, Co. Londonderry, BT52 1SA, Northern Ireland, UK ;
| | - Peter R Flatt
- SAAD Centre for Diabetes and Pharmacy, School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine, Co. Londonderry, BT52 1SA, Northern Ireland, UK
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Abstract
Glucose-dependent insulinotropic polypeptide (GIP or gastric inhibitory polypeptide) is a 42-amino-acid hormone, secreted from the enteroendocrine K cells, which has insulin-releasing and extrapancreatic glucoregulatory actions. However, the unfavourable pharmacokinetic profile and the weak biological effects of native GIP limit its effectiveness for the treatment of type 2 diabetes. To overcome this, longer-acting GIP agonists exhibiting enzymatic stability and enhanced bioactivity have been generated and successfully tested in animal models of diabetes. Thus, GIP receptor agonists offer one of the newest classes of potential antidiabetic drug. GIP is also known to play a role in lipid metabolism and fat deposition. Accordingly, both genetic and chemical ablation of GIP signalling in mice with obesity-diabetes can protect against, or even reverse many of the obesity-associated metabolic disturbances. Strong parallels exist with the beneficial metabolic effects of Roux-en-Y gastric bypass in obese, insulin-resistant humans that surgically ablates GIP-secreting K cells. The purpose of this article is to highlight the therapeutic potential of GIP-based therapeutics in the treatment of type 2 diabetes and obesity.
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Affiliation(s)
- Nigel Irwin
- School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine, Co. Londonderry, BT52 1SA, Northern Ireland, UK.
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Fatty acid derivatised analogues of glucose-dependent insulinotropic polypeptide with improved antihyperglycaemic and insulinotropic properties. Biochem Pharmacol 2009; 78:1008-16. [PMID: 19523458 DOI: 10.1016/j.bcp.2009.05.037] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Revised: 05/28/2009] [Accepted: 05/29/2009] [Indexed: 11/24/2022]
Abstract
C-terminal acylation of Lys(37) with myristic (MYR; tetradecanoic acid), palmitic (PAL; hexadecanoic acid) and stearic (octadecanoic acid) fatty acids with or without N-terminal acetylation was employed to develop long-acting analogues of the glucoregulatory hormone, glucose-dependent insulinotropic polypeptide (GIP). All GIP analogues exhibited resistance to dipeptidylpeptidase-IV (DPP-IV) and significantly improved in vitro cAMP production and insulin secretion. Administration of GIP analogues to ob/ob mice significantly lowered plasma glucose-GIP(Lys(37)MYR), N-AcGIP(Lys(37)MYR) and GIP(Lys(37)PAL) increased plasma insulin concentrations. GIP(Lys(37)MYR) and N-AcGIP(Lys(37)MYR) elicited protracted glucose-lowering effects when administered 24h prior to an intraperitoneal glucose load. Daily administration of GIP(Lys(37)MYR) and N-AcGIP(Lys(37)MYR) to ob/ob mice for 24 days decreased glucose and significantly improved plasma insulin, glucose tolerance and beta-cell glucose responsiveness. Insulin sensitivity, pancreatic insulin content and triglyceride levels were not changed. These data demonstrate that C-terminal acylation particularly with myristic acid provides a class of stable, longer-acting forms of GIP for further evaluation in diabetes therapy.
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Chapter 15 Glucose‐Dependent Insulinotropic Polypeptide (Gastric Inhibitory Polypeptide; GIP). VITAMINS AND HORMONES 2009; 80:409-71. [DOI: 10.1016/s0083-6729(08)00615-8] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Gault VA, Kerr BD, Irwin N, Flatt PR. C-terminal mini-PEGylation of glucose-dependent insulinotropic polypeptide exhibits metabolic stability and improved glucose homeostasis in dietary-induced diabetes. Biochem Pharmacol 2008; 75:2325-33. [PMID: 18455149 DOI: 10.1016/j.bcp.2008.03.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 03/18/2008] [Accepted: 03/18/2008] [Indexed: 12/25/2022]
Abstract
Glucose-dependent insulinotropic polypeptide has been proposed as a potential therapeutic for type 2 diabetes, however, efforts to bring forward this drug have been hindered due to its short circulating half-life. We have adopted a novel strategy to increase potency and prolong GIP action through C-terminal mini-PEGylation (GIP[mPEG]). In contrast to GIP, GIP[mPEG] was resistant to dipeptidylpeptidase-IV (DPP-IV) up to and including 24h. Both GIP[mPEG] and GIP concentration-dependently stimulated cAMP production (EC50 6.6 and 0.7 nM, respectively) and insulin secretion (p < 0.01 to p < 0.001) in pancreatic BRIN-BD11 cells. Acute injection of GIP[mPEG] together with glucose to high fat fed mice significantly lowered plasma glucose (p < 0.05) and increased plasma insulin responses (p < 0.05). Furthermore, GIP[mPEG] markedly lowered plasma glucose when administered 4-24h prior to a glucose load (p < 0.05). Daily administration of GIP[mPEG] for 20 days in high fat mice did not alter body weight, food intake or non-fasting plasma insulin, however, non-fasting plasma glucose concentrations were significantly lowered (p < 0.05). Moreover, glucose tolerance was significantly improved (p < 0.05) together with glucose-mediated plasma insulin responses (p < 0.05). Insulin sensitivity, pancreatic insulin content, triglyceride and adiponectin levels were not changed. In summary, these data demonstrate that C-terminal mini-PEGylation of GIP is a useful strategy to prolong metabolic stability and improve biological action thus representing a novel therapeutic option for type 2 diabetes.
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Affiliation(s)
- Victor A Gault
- School of Biomedical Sciences, University of Ulster, Cromore Road, Coleraine BT52 1SA, Northern Ireland, United Kingdom.
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27
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Abstract
The incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are physiological gut peptides with insulin-releasing and extrapancreatic glucoregulatory actions. Incretin analogues/mimetics activate GLP-1 or GIP receptors whilst avoiding physiological inactivation by dipeptidyl peptidase 4 (DPP-4), and they represent one of the newest classes of antidiabetic drug. The first clinically approved GLP-1 mimetic for the treatment of type-2 diabetes is exenatide (Byetta/exendin) which is administered subcutaneously twice daily. Clinical trials of liraglutide, a GLP-1 analogue suitable for once-daily administration, are ongoing. A number of other incretin molecules are at earlier stages of development. This review discusses the various attributes of GLP-1 and GIP for diabetes treatment and summarises current clinical data. Additionally, it explores the therapeutic possibilities offered by preclinical agents, such as non-peptide GLP-1 mimetics, GLP-1/glucagon hybrid peptides, and specific GIP receptor antagonists.
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Affiliation(s)
- Brian D Green
- School of Biological Sciences, Queens University Belfast, David Keir Building, Stranmillis Road, Belfast BT6 0NJ, Northern Ireland, UK.
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28
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Gault VA, McClean PL, Irwin N, Power GJ, McCluskey JT, Flatt PR. Effects of subchronic treatment with the long-acting glucose-dependent insulinotropic polypeptide receptor agonist, N-AcGIP, on glucose homeostasis in streptozotocin-induced diabetes. Pancreas 2007; 35:73-9. [PMID: 17575548 DOI: 10.1097/mpa.0b013e31804fa19a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVES N-AcGIP is a potent and dipeptidylpeptidase IV-resistant analogue of glucose-dependent insulinotropic polypeptide with significantly improved antidiabetic actions in type 2 diabetes. The present study investigated the effects of subchronic treatment with N-AcGIP on glucose homeostasis in a type 1 model, namely, streptozotocin (STZ)-induced diabetic mice. METHODS Swiss TO mice given a single intraperitoneal injection of STZ (150 mg/kg body weight) received once-daily injection of N-AcGIP (25 nmol/kg body weight) or saline for 20 days and effects on metabolic parameters and islet architecture assessed. RESULTS Daily injection of N-AcGIP for 20 days did not significantly alter the characteristic STZ-induced changes of pancreatic insulin content, body weight, food intake, glucose, and glycated hemoglobin levels. Glucose tolerance and insulin sensitivity were also unchanged by N-AcGIP treatment. Circulating insulin was undetectable, and the number of intact islets and insulin expression was greatly reduced in both groups. Some proliferative activity was identified by 5-bromo-2-deoxyuridine staining in the pancreas, but this and expression of glucagon and somatostatin were similar in the 2 groups. CONCLUSIONS These data indicate that subchronic treatment with the long-acting glucose-dependent insulinotropic polypeptide receptor agonist, N-AcGIP, does not have beneficial effects in insulin-deficient STZ-diabetic mice. This supports the primary antidiabetic action of this analogue in type 2 diabetes as stimulation of beta-cell function and insulin secretion.
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Affiliation(s)
- Victor A Gault
- Diabetes Research Group, School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK.
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29
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Malde AK, Srivastava SS, Coutinho EC. Understanding interactions of gastric inhibitory polypeptide (GIP) with its G-protein coupled receptor through NMR and molecular modeling. J Pept Sci 2007; 13:287-300. [PMID: 17437246 DOI: 10.1002/psc.839] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Gastric inhibitory polypeptide (GIP, or glucose-dependent insulinotropic polypeptide) is a 42-amino acid incretin hormone moderating glucose-induced insulin secretion. Antidiabetic therapy based on GIP holds great promise because of the fact that its insulinotropic action is highly dependent on the level of glucose, overcoming the sideeffects of hypoglycemia associated with the current therapy of Type 2 diabetes. The truncated peptide, GIP(1-30)NH2, has the same activity as the full length native peptide. We have studied the structure of GIP(1-30)NH2 and built a model of its G-protein coupled receptor (GPCR). The structure of GIP(1-30)NH2 in DMSO-d6 and H2O has been studied using 2D NMR (total correlation spectroscopy (TOCSY), nuclear overhauser effect spectroscopy (NOESY), double quantum filtered-COSY (DQF-COSY), 13C-heteronuclear single quantum correlation (HSQC) experiments, and its conformation built by MD simulations with the NMR data as constraints. The peptide in DMSO-d6 exhibits an alpha-helix between residues Ile12 and Lys30 with a discontinuity at residues Gln19 and Gln20. In H2O, the alpha-helix starts at Ile7, breaks off at Gln19, and then continues right through to Lys30. GIP(1-30)NH2 has all the structural features of peptides belonging to family B1 GPCRs, which are characterized by a coil at the N-terminal and a long C-terminal alpha-helix with or without a break. A model of the seven transmembrane (TM) helices of the GIP receptor (GIPR) has been built on the principles of comparative protein modeling, using the crystal structure of bovine rhodopsin as a template. The N-terminal domain of GIPR has been constructed from the NMR structure of the N-terminal of corticoptropin releasing factor receptor (CRFR), a family B1 GCPR. The intra and extra cellular loops and the C-terminal have been modeled from fragments retrieved from the PDB. On the basis of the experimental data available for some members of family B1 GPCRs, four pairs of constraints between GIP(1-30)NH2 and its receptor were used in the FTDOCK program, to build the complete model of the GIP(1-30)NH2:GIPR complex. The model can rationalize the various experimental observations including the potency of the truncated GIP peptide. This work is the first complete model at the atomic level of GIP(1-30)NH2 and of the complex with its GPCR.
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MESH Headings
- Diabetes Mellitus, Type 2/drug therapy
- Diabetes Mellitus, Type 2/metabolism
- Gastric Inhibitory Polypeptide/chemistry
- Gastric Inhibitory Polypeptide/metabolism
- Gastric Inhibitory Polypeptide/therapeutic use
- Gastrointestinal Agents/chemistry
- Gastrointestinal Agents/metabolism
- Gastrointestinal Agents/therapeutic use
- Glucose/metabolism
- Humans
- Insulin/metabolism
- Models, Molecular
- Nuclear Magnetic Resonance, Biomolecular
- Protein Structure, Quaternary
- Protein Structure, Secondary
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/metabolism
- Receptors, Gastrointestinal Hormone/chemistry
- Receptors, Gastrointestinal Hormone/metabolism
- Structure-Activity Relationship
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Affiliation(s)
- Alpeshkumar K Malde
- Department of Pharmaceutical Chemistry, Bombay College of Pharmacy, Kalina, Santacruz (E), Mumbai 400 098, India
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30
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Flatt PR, Green BD. Nutrient regulation of pancreatic β-cell function in diabetes: problems and potential solutions. Biochem Soc Trans 2006; 34:774-8. [PMID: 17052195 DOI: 10.1042/bst0340774] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Increasing prevalence of obesity combined with longevity will produce an epidemic of Type 2 (non-insulin-dependent) diabetes in the next 20 years. This disease is associated with defects in insulin secretion, specifically abnormalities of insulin secretory kinetics and pancreatic β-cell glucose responsiveness. Mechanisms underlying β-cell dysfunction include glucose toxicity, lipotoxicity and β-cell hyperactivity. Defects at various sites in β-cell signal transduction pathways contribute, but no single lesion can account for the common form of Type 2 diabetes. Recent studies highlight diverse β-cell actions of GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). These intestinal hormones target the β-cell to stimulate glucose-dependent insulin secretion through activation of protein kinase A and associated pathways. Both increase gene expression and proinsulin biosynthesis, protect against apoptosis and stimulate replication/neogenesis of β-cells. Incretin hormones therefore represent an exciting future multi-action solution to correct β-cell defect in Type 2 diabetes.
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Affiliation(s)
- P R Flatt
- School of Biomedical Sciences, University of Ulster, Coleraine BT52 1SA, UK.
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31
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Irwin N, Clarke GC, Green BD, Greer B, Harriott P, Gault VA, O'Harte FPM, Flatt PR. Evaluation of the antidiabetic activity of DPP IV resistant N-terminally modified versus mid-chain acylated analogues of glucose-dependent insulinotropic polypeptide. Biochem Pharmacol 2006; 72:719-28. [PMID: 16859646 DOI: 10.1016/j.bcp.2006.06.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 06/12/2006] [Accepted: 06/12/2006] [Indexed: 10/24/2022]
Abstract
Glucose dependent insulinotropic polypeptide (GIP) is a gastrointestinal hormone with therapeutic potential for type 2 diabetes due to its insulin-releasing and antihyperglycaemic actions. However, development of GIP-based therapies is limited by N-terminal degradation by DPP IV resulting in a very short circulating half-life. Numerous GIP analogues have now been generated exhibiting DPP IV resistance and extended bioactivity profiles. In this study, we report a direct comparison of the long-term antidiabetic actions of three such GIP molecules, N-AcGIP, GIP(Lys(37)PAL) and N-AcGIP(Lys(37)PAL) in obese diabetic (ob/ob) mice. An extended duration of action of each GIP analogue was demonstrated prior to examining the effects of once daily injections (25nmolkg(-1) body weight) over a 14-day period. Administration of either N-AcGIP, GIP(Lys(37)PAL) or N-AcGIP(Lys(37)PAL) significantly decreased non-fasting plasma glucose and improved glucose tolerance compared to saline treated controls. All three analogues significantly enhanced glucose and nutrient-induced insulin release, and improved insulin sensitivity. The metabolic and insulin secretory responses to native GIP were also enhanced in 14-day analogue treated mice, revealing no evidence of GIP-receptor desensitization. These effects were accompanied by significantly enhanced pancreatic insulin following N-AcGIP(Lys(37)PAL) and increased islet number and islet size in all three groups. Body weight, food intake and circulating glucagon were unchanged. These data demonstrate the therapeutic potential of once daily injection of enzyme resistant GIP analogues and indicate that N-AcGIP is equally as effective as related palmitate derivatised analogues of GIP.
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Affiliation(s)
- Nigel Irwin
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK.
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32
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Werle M, Bernkop-Schnürch A. Strategies to improve plasma half life time of peptide and protein drugs. Amino Acids 2006; 30:351-67. [PMID: 16622600 DOI: 10.1007/s00726-005-0289-3] [Citation(s) in RCA: 469] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Accepted: 12/16/2005] [Indexed: 10/24/2022]
Abstract
Due to the obvious advantages of long-acting peptide and protein drugs, strategies to prolong plasma half life time of such compounds are highly on demand. Short plasma half life times are commonly due to fast renal clearance as well as to enzymatic degradation occurring during systemic circulation. Modifications of the peptide/protein can lead to prolonged plasma half life times. By shortening the overall amino acid amount of somatostatin and replacing L: -analogue amino acids with D: -amino acids, plasma half life time of the derivate octreotide was 1.5 hours in comparison to only few minutes of somatostatin. A PEG(2,40 K) conjugate of INF-alpha-2b exhibited a 330-fold prolonged plasma half life time compared to the native protein. It was the aim of this review to provide an overview of possible strategies to prolong plasma half life time such as modification of N- and C-terminus or PEGylation as well as methods to evaluate the effectiveness of drug modifications. Furthermore, fundamental data about most important proteolytic enzymes of human blood, liver and kidney as well as their cleavage specificity and inhibitors for them are provided in order to predict enzymatic cleavage of peptide and protein drugs during systemic circulation.
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Affiliation(s)
- M Werle
- ThioMatrix GmbH, Research Center Innsbruck, Innsbruck, Austria
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33
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Irwin N, O'Harte FPM, Gault VA, Green BD, Greer B, Harriott P, Bailey CJ, Flatt PR. GIP(Lys16PAL) and GIP(Lys37PAL): novel long-acting acylated analogues of glucose-dependent insulinotropic polypeptide with improved antidiabetic potential. J Med Chem 2006; 49:1047-54. [PMID: 16451070 DOI: 10.1021/jm0509997] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Glucose-dependent insulinotropic polypeptide (GIP) is a physiological insulin releasing peptide. We have developed two novel fatty acid derivatized GIP analogues, which bind to serum albumin and demonstrate enhanced duration of action in vivo. GIP(Lys(16)PAL) and GIP(Lys(37)PAL) were resistant to dipeptidyl peptidase IV (DPP IV) degradation. In vitro studies demonstrated that GIP analogues retained their ability to activate the GIP receptor through production of cAMP and to stimulate insulin secretion. Intraperitoneal administration of GIP analogues to obese diabetic (ob/ob) mice significantly decreased the glycemic excursion and elicited increased and prolonged insulin responses compared to native GIP. A protracted glucose-lowering effect was observed 24 h following GIP(Lys(37)PAL) administration. Once a day injection for 14 days decreased nonfasting glucose, improved glucose tolerance, and enhanced the insulin response to glucose. These data demonstrate that fatty acid derivatized GIP peptides represent a novel class of long-acting stable GIP analogues for therapy of type 2 diabetes.
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Affiliation(s)
- Nigel Irwin
- School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, U.K.
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34
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Salhanick AI, Clairmont KB, Buckholz TM, Pellegrino CM, Ha S, Lumb KJ. Contribution of site-specific PEGylation to the dipeptidyl peptidase IV stability of glucose-dependent insulinotropic polypeptide. Bioorg Med Chem Lett 2005; 15:4114-7. [PMID: 15993590 DOI: 10.1016/j.bmcl.2005.06.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2005] [Revised: 05/27/2005] [Accepted: 06/02/2005] [Indexed: 01/12/2023]
Abstract
The effects of PEGylation of glucose-dependent insulinotropic polypeptide (GIP) on potency and dipeptidyl peptidase IV (DPPIV) stability are reported. N-terminal modification of GIP(1-30) with 40 kDa polyethylene glycol (PEG) abrogates functional activity. In contrast, C-terminal PEGylation of GIP(1-30) maintains full agonism and reasonable potency at the GIP receptor and confers a high level of DPPIV resistance. Moreover, the dual modification of N-terminal palmitoylation and C-terminal PEGylation results in a full agonist of comparable potency to native GIP that is stable to DPPIV cleavage. The results provide the basis for the development of long acting, PEGylated GIP, GIP variants, or GIP-based hybrid peptide therapeutics.
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Affiliation(s)
- Arthur I Salhanick
- Department of Metabolic Disorders Research, Bayer Pharmaceuticals Corporation, 400 Morgan Lane, West Haven, CT 06516, USA
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