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Rosenstock J, Juneja R, Beals JM, Moyers JS, Ilag L, McCrimmon RJ. The Basis for Weekly Insulin Therapy: Evolving Evidence With Insulin Icodec and Insulin Efsitora Alfa. Endocr Rev 2024; 45:379-413. [PMID: 38224978 DOI: 10.1210/endrev/bnad037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Indexed: 01/17/2024]
Abstract
Basal insulin continues to be a vital part of therapy for many people with diabetes. First attempts to prolong the duration of insulin formulations were through the development of suspensions that required homogenization prior to injection. These insulins, which required once- or twice-daily injections, introduced wide variations in insulin exposure contributing to unpredictable effects on glycemia. Advances over the last 2 decades have resulted in long-acting, soluble basal insulin analogues with prolonged and less variable pharmacokinetic exposure, improving their efficacy and safety, notably by reducing nocturnal hypoglycemia. However, adherence and persistence with once-daily basal insulin treatment remains low for many reasons including hypoglycemia concerns and treatment burden. A soluble basal insulin with a longer and flatter exposure profile could reduce pharmacodynamic variability, potentially reducing hypoglycemia, have similar efficacy to once-daily basal insulins, simplify dosing regimens, and improve treatment adherence. Insulin icodec (Novo Nordisk) and insulin efsitora alfa (basal insulin Fc [BIF], Eli Lilly and Company) are 2 such insulins designed for once-weekly administration, which have the potential to provide a further advance in basal insulin replacement. Icodec and efsitora phase 2 clinical trials, as well as data from the phase 3 icodec program indicate that once-weekly insulins provide comparable glycemic control to once-daily analogues, with a similar risk of hypoglycemia. This manuscript details the technology used in the development of once-weekly basal insulins. It highlights the clinical rationale and potential benefits of these weekly insulins while also discussing the limitations and challenges these molecules could pose in clinical practice.
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Affiliation(s)
- Julio Rosenstock
- Velocity Clinical Research at Medical City, Dallas, TX 75230, USA
| | - Rattan Juneja
- Lilly Diabetes and Obesity, Eli Lilly and Company, Indianapolis, IN 46225, USA
| | - John M Beals
- Lilly Diabetes and Obesity, Eli Lilly and Company, Indianapolis, IN 46225, USA
| | - Julie S Moyers
- Lilly Diabetes and Obesity, Eli Lilly and Company, Indianapolis, IN 46225, USA
| | - Liza Ilag
- Lilly Diabetes and Obesity, Eli Lilly and Company, Indianapolis, IN 46225, USA
| | - Rory J McCrimmon
- School of Medicine, University of Dundee, Dundee DD1 9SY, Scotland, UK
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2
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Ye L, Liu X, Jin K, Niu Y, Zuo Q, Song J, Han W, Chen G, Li B. Effects of Insulin on Proliferation, Apoptosis, and Ferroptosis in Primordial Germ Cells via PI3K-AKT-mTOR Signaling Pathway. Genes (Basel) 2023; 14:1975. [PMID: 37895324 PMCID: PMC10606282 DOI: 10.3390/genes14101975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/18/2023] [Accepted: 10/20/2023] [Indexed: 10/29/2023] Open
Abstract
Primordial germ cells (PGCs) are essential for the genetic modification, resource conservation, and recovery of endangered breeds in chickens and need to remain viable and proliferative in vitro. Therefore, there is an urgent need to elucidate the functions of the influencing factors and their regulatory mechanisms. In this study, PGCs collected from Rugao yellow chicken embryonic eggs at Day 5.5 were cultured in media containing 0, 5, 10, 20, 50, and 100 μg/mL insulin. The results showed that insulin regulates cell proliferation in PGCs in a dose-dependent way, with an optimal dose of 10 μg/mL. Insulin mediates the mRNA expression of cell cycle-, apoptosis-, and ferroptosis-related genes. Insulin at 50 μg/mL and 100 μg/mL slowed down the proliferation with elevated ion content and GSH/oxidized glutathione (GSSG) in PGCs compared to 10 μg/mL. In addition, insulin activates the PI3K/AKT/mTOR pathway dose dependently. Collectively, this study demonstrates that insulin reduces apoptosis and ferroptosis and enhances cell proliferation in a dose-dependent manner via the PI3K-AKT-mTOR signaling pathway in PGCs, providing a new addition to the theory of the regulatory role of the growth and proliferation of PGC in vitro cultures.
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Affiliation(s)
- Liu Ye
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Xin Liu
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Kai Jin
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Yingjie Niu
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Qisheng Zuo
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Jiuzhou Song
- Animal & Avian Sciences, University of Maryland, College Park, MA 20742, USA;
| | - Wei Han
- Poultry Institute, Chinese Academy of Agricultural Sciences/Poultry Institute of Jiangsu, Yangzhou 225003, China;
| | - Guohong Chen
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
| | - Bichun Li
- Key Laboratory of Animal Breeding Reproduction and Molecular Design for Jiangsu Province, College of Animal Science and Technology, Yangzhou University, Yangzhou 225009, China; (L.Y.); (X.L.); (K.J.); (Y.N.); (Q.Z.)
- Institutes of Agricultural Science and Technology Development, Yangzhou University, Yangzhou 225009, China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China, Yangzhou University, Yangzhou 225009, China
- College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang 212100, China
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Le TKC, Dao XD, Nguyen DV, Luu DH, Bui TMH, Le TH, Nguyen HT, Le TN, Hosaka T, Nguyen TTT. Insulin signaling and its application. Front Endocrinol (Lausanne) 2023; 14:1226655. [PMID: 37664840 PMCID: PMC10469844 DOI: 10.3389/fendo.2023.1226655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/19/2023] [Indexed: 09/05/2023] Open
Abstract
The discovery of insulin in 1921 introduced a new branch of research into insulin activity and insulin resistance. Many discoveries in this field have been applied to diagnosing and treating diseases related to insulin resistance. In this mini-review, the authors attempt to synthesize the updated discoveries to unravel the related mechanisms and inform the development of novel applications. Firstly, we depict the insulin signaling pathway to explain the physiology of insulin action starting at the receptor sites of insulin and downstream the signaling of the insulin signaling pathway. Based on this, the next part will analyze the mechanisms of insulin resistance with two major provenances: the defects caused by receptors and the defects due to extra-receptor causes, but in this study, we focus on post-receptor causes. Finally, we discuss the recent applications including the diseases related to insulin resistance (obesity, cardiovascular disease, Alzheimer's disease, and cancer) and the potential treatment of those based on insulin resistance mechanisms.
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Affiliation(s)
- Thi Kim Chung Le
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Xuan Dat Dao
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Dang Vung Nguyen
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Duc Huy Luu
- Department of Biopharmaceuticals, Institute of Chemistry, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Thi Minh Hanh Bui
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Thi Huong Le
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Huu Thang Nguyen
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Tran Ngoan Le
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
| | - Toshio Hosaka
- Department of Food and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan
| | - Thi Thu Thao Nguyen
- School of Preventive Medicine and Public Health, Hanoi Medical University, Hanoi, Vietnam
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Liu H, Li T, Yu H, Chen X, Li J, Tan H, Jia D, Yu Y. A phase-I randomized euglycemic clamp study to demonstrate the pharmacokinetic and pharmacodynamic equivalence of an insulin degludec biosimilar (B01411) with the reference product in healthy Chinese volunteers. Expert Opin Investig Drugs 2023; 32:773-781. [PMID: 37665683 DOI: 10.1080/13543784.2023.2254690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 08/30/2023] [Indexed: 09/06/2023]
Abstract
BACKGROUND B01411 is a biosimilar candidate manufactured by Jilin Huisheng Biopharmaceutical Co. Ltd for the reference insulin degludec (Tresiba) (IDeg). This study aimed to evaluate the pharmacokinetics (PK), pharmacodynamics (PD), and safety of the two IDeg products and to assess the PK/PD similarity of B01411 compared with the reference IDeg product. RESEARCH DESIGN & METHODS A single-center, single-dose, randomized, crossover, open-labeled, phase I, euglycemic clamp study in healthy Chinese subjects to examine the bioequivalence of B01411 (0.4 U/kg) compared with the reference IDeg product. Blood samples were collected at a predefined time for the analysis of blood glucose (BG), IDeg, and C-peptide concentrations. The glucose infusion rate (GIR) was adjusted to maintain the BG at approximately 0.28 mmol/L below baseline throughout the clamp. RESULTS Thirty-two subjects (20 males and 12 females) were enrolled, 31 of whom received both treatments. The 90% confidence intervals for the ratio of the least-squares geometric means for AUCIDeg,0-24 h, AUCGIR,0-24 h, IDegmax, and GIRmax were all in the range of 0.80-1.25. Only one adverse event of puncture site bruising occurred once in a subject in the B01411 group. CONCLUSION B01411 exhibited a pharmacokinetic and pharmacodynamic similarity to the reference product. Both IDeg products were well tolerated. CLINICAL TRIAL REGISTRATION http://www.chinadrugtrials.org.cn/index.html#. Identifier is CTR20192122.
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Affiliation(s)
- Hui Liu
- General Practice Ward/International Medical Center Ward, General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Ting Li
- Health Management Center, General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Hongling Yu
- Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China
| | - Xinlei Chen
- Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China
| | - Jiaqi Li
- Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China
| | - Huiwen Tan
- Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China
| | - Dejia Jia
- Department of Research and Development, Jilin Huisheng Biopharmaceutical Co. Ltd, Jilin, China
| | - Yerong Yu
- Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, China
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5
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Abstract
Insulin is a peptide hormone essential for maintaining normal blood glucose levels. Individuals unable to secrete sufficient insulin or not able to respond properly to insulin develop diabetes. Since the discovery of insulin its structure and function has been intensively studied with the aim to develop effective diabetes treatments. The three-dimensional crystal structure of this 51 amino acid peptide paved the way for discoveries, outlined in this review, of determinants important for receptor binding and hormone stability that have been instrumental in development of insulin analogs used in the clinic today. Important for the future development of effective diabetes treatments will be a detailed understanding of the insulin receptor structure and function. Determination of the three-dimensional structure of the insulin receptor, a receptor tyrosine kinase, proved challenging but with the recent advent of high-resolution cryo-electron microscopy significant progress has been made. There are now >40 structures of the insulin:insulin receptor complex deposited in the Protein Data Bank. From these structures we have a detailed picture of how insulin binds and activates the receptor. Still lacking are details of the initial binding events and the exact sequence of structural changes within the receptor and insulin. In this review, the focus will be on the most recent structural studies of insulin:insulin receptor complexes and how they have contributed to the current understanding of insulin receptor activation and signaling outcome. Molecular mechanisms underlying insulin receptor signaling bias emerging from the latest structures are described.
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Affiliation(s)
- Briony E Forbes
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia.
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Moyers JS, Hansen RJ, Day JW, Dickinson CD, Zhang C, Ruan X, Ding L, Brown RM, Baker HE, Beals JM. Preclinical Characterization of LY3209590, a Novel Weekly Basal Insulin Fc-fusion Protein. J Pharmacol Exp Ther 2022; 382:346-355. [PMID: 35840338 DOI: 10.1124/jpet.122.001105] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 06/17/2022] [Indexed: 11/22/2022] Open
Abstract
The benefit of once-weekly basal insulin is less frequent dosing, which has the potential to reduce the barrier to injection therapy and impact patient activation, adherence/compliance, quality of life, and outcomes. Basal Insulin Fc (BIF, LY3209590, or insulin efsitora alfa) is a once-weekly basal insulin in clinical testing for type 1 and type 2 diabetes mellitus. BIF is comprised of a novel single-chain variant of insulin fused to a human IgG2 Fc domain using a peptide linker. The in vitro binding affinity of BIF for the human insulin receptor (IR) was two orders of magnitude weaker relative to human insulin. BIF stimulated IR phosphorylation in cells with reduced potency, yet full agonism, and exhibited a significantly faster dephosphorylation kinetic profile than human insulin or AspB10 insulin. BIF stimulated de novo lipogenesis in 3T3-L1 adipocytes and cell proliferation in SAOS-2 and H4IIE cells with {greater than or equal to}70-fold reduction in in vitro potency compared to human insulin. BIF possessed markedly reduced binding to hIGF-1R making definitive measurements unattainable. In vivo pharmacology studies using streptozotocin-treated diabetic rats demonstrated a significant decrease in blood glucose compared to vehicle-treated animals 24h post-injection, persisting through 336h following subcutaneous administration. In streptozotocin-treated rats, BIF reached Tmax at 48h and possessed a clearance rate of ~0.85 mL/hr/kg, with a t1/2 of ~120h following subcutaneous administration. These results demonstrate BIF has an in vitro pharmacological profile similar to native insulin, with significantly reduced potency and an extended time-action profile in vivo that supports QW dosing in humans. Significance Statement BIF is a novel basal insulin Fc-fusion protein designed for once-weekly dosing. In this study we demonstrate that BIF has an in vitro pharmacological profile similar to human insulin, but with weaker potency across assays for IR binding and activity. BIF has a PD and PK profile in STZ-treated rats supportive of weekly dosing in humans.
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Affiliation(s)
- Julie S Moyers
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | - Ryan J Hansen
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | - Jonathan W Day
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | | | - Chen Zhang
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | - Xiaoping Ruan
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | - Liyun Ding
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | - Robin M Brown
- Lilly Research Laboratories, Eli Lilly and Company, United States
| | - Hana E Baker
- Lilly Research Laboratories, Eli Lilly and Company, United States
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7
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Xiong X, Blakely A, Kim JH, Menting JG, Schäfer IB, Schubert HL, Agrawal R, Gutmann T, Delaine C, Zhang YW, Artik GO, Merriman A, Eckert D, Lawrence MC, Coskun Ü, Fisher SJ, Forbes BE, Safavi-Hemami H, Hill CP, Chou DHC. Symmetric and asymmetric receptor conformation continuum induced by a new insulin. Nat Chem Biol 2022; 18:511-519. [PMID: 35289328 PMCID: PMC9248236 DOI: 10.1038/s41589-022-00981-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 01/24/2022] [Indexed: 02/02/2023]
Abstract
Cone snail venoms contain a wide variety of bioactive peptides, including insulin-like molecules with distinct structural features, binding modes and biochemical properties. Here, we report an active humanized cone snail venom insulin with an elongated A chain and a truncated B chain, and use cryo-electron microscopy (cryo-EM) and protein engineering to elucidate its interactions with the human insulin receptor (IR) ectodomain. We reveal how an extended A chain can compensate for deletion of B-chain residues, which are essential for activity of human insulin but also compromise therapeutic utility by delaying dissolution from the site of subcutaneous injection. This finding suggests approaches to developing improved therapeutic insulins. Curiously, the receptor displays a continuum of conformations from the symmetric state to a highly asymmetric low-abundance structure that displays coordination of a single humanized venom insulin using elements from both of the previously characterized site 1 and site 2 interactions.
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Affiliation(s)
- Xiaochun Xiong
- Department of Pediatrics, Division of Endocrinology and Diabetes, Stanford University, Stanford, CA, USA.,Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Alan Blakely
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Jin Hwan Kim
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - John G Menting
- WEHI, Parkville, Victoria, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Ingmar B Schäfer
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Munich, Germany
| | - Heidi L Schubert
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Rahul Agrawal
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Theresia Gutmann
- Paul Langerhans Institute Dresden, Helmholtz Zentrum München, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany.,Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Carlie Delaine
- Discipline of Medical Biochemistry and Cell Biology, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
| | - Yi Wolf Zhang
- Department of Pediatrics, Division of Endocrinology and Diabetes, Stanford University, Stanford, CA, USA.,Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Gizem Olay Artik
- Paul Langerhans Institute Dresden, Helmholtz Zentrum München, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany.,Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,Department of Membrane Biochemistry and Lipid Research, University Clinic Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Allanah Merriman
- Discipline of Medical Biochemistry and Cell Biology, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
| | - Debbie Eckert
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA
| | - Michael C Lawrence
- WEHI, Parkville, Victoria, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Ünal Coskun
- Paul Langerhans Institute Dresden, Helmholtz Zentrum München, University Hospital and Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany.,Faculty of Medicine Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,Department of Membrane Biochemistry and Lipid Research, University Clinic Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Simon J Fisher
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Kentucky, Lexington, KY, USA
| | - Briony E Forbes
- Discipline of Medical Biochemistry and Cell Biology, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
| | - Helena Safavi-Hemami
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA. .,Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Christopher P Hill
- Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
| | - Danny Hung-Chieh Chou
- Department of Pediatrics, Division of Endocrinology and Diabetes, Stanford University, Stanford, CA, USA. .,Department of Biochemistry, University of Utah, Salt Lake City, UT, USA.
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Ding J, Li X, Ge J, Gong Y, Zhou Y, Xiao J, Yang Q, Chen J, Mao M. Survival Risk Analysis of Small Cell Lung Cancer Patients with Pre-Existing Type 2 Diabetes Mellitus: A Single-Center Retrospective Cohort Study. Cancer Manag Res 2022; 14:1313-1322. [PMID: 35386185 PMCID: PMC8979423 DOI: 10.2147/cmar.s340334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 03/10/2022] [Indexed: 11/26/2022] Open
Abstract
Purpose We aimed to investigate the clinicopathological characteristics and survival risk factors in small cell lung cancer (SCLC) patients with preexisting type 2 diabetes mellitus (preDM). Patients and Methods All patients with SCLC admitted to our hospital between January 2013 and August 2018 were followed up until August 2020 and retrospectively analyzed. Clinical characteristics of SCLC patients with and without preDM were extracted. Cox proportional hazards models were conducted to identify potential independent prognostic factors. Results Of 628 eligible individuals, 88 individuals had preDM. preDM was independently significantly associated with distant metastasis in all SCLC patients (p =0.016, OR=1.80, 95% CI 1.11–2.91), while preDM did not affect the outcome of SCLC patients (p=0.803, HR=1.04, 95% CI 0.79–1.36) by multivariate analysis. In the preDM group, the median overall survival (OS) was shorter in the insulin group than in the non insulin group (13.93 months versus 21.77 months, p=0.024). Multivariate analysis identified that insulin treatment was an independent unfavorable factor associated with OS (p =0.009, HR=2.10, 95% CI 1.19–3.64). In addition, poorer performance status (PS) and liver metastasis were also independent unfavorable prognostic factors (all p<0.01), while thoracic therapy significantly improved OS and decreased mortality risk in diabetic patients with SCLC (p<0.05). Conclusion preDM may promote distant metastasis of SCLC while it is insulin therapy and not preDM which adversely affects the prognosis of SCLC patients. These findings indicate that enhancing blood glucose control and reducing insulin analog use may be essential to the improvement of the long-term survival of the diabetic population with SCLC.
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Affiliation(s)
- Jing Ding
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Xudong Li
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Jun Ge
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Yuanqian Gong
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Ya Zhou
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Juan Xiao
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Qin Yang
- Department of Oncology, Bazhong Central Hospital, Bazhong, Sichuan, People’s Republic of China
| | - Jing Chen
- Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
| | - Mian Mao
- Department of Pharmacy, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, Sichuan, People’s Republic of China
- Correspondence: Mian Mao, Tel/Fax +86-28-85420311, Email
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9
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Ong SC, Belgi A, Merriman AL, Delaine CA, van Lierop B, Andrikopoulos S, Robinson AJ, Forbes BE. Minimizing Mitogenic Potency of Insulin Analogues Through Modification of a Disulfide Bond. Front Endocrinol (Lausanne) 2022; 13:907864. [PMID: 35832429 PMCID: PMC9271792 DOI: 10.3389/fendo.2022.907864] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/09/2022] [Indexed: 11/13/2022] Open
Abstract
The mechanisms by which insulin activates the insulin receptor to promote metabolic processes and cellular growth are still not clear. Significant advances have been gained from recent structural studies in understanding how insulin binds to its receptor. However, the way in which specific interactions lead to either metabolic or mitogenic signalling remains unknown. Currently there are only a few examples of insulin receptor agonists that have biased signalling properties. Here we use novel insulin analogues that differ only in the chemical composition at the A6-A11 bond, as it has been changed to a rigid, non-reducible C=C linkage (dicarba bond), to reveal mechanisms underlying signaling bias. We show that introduction of an A6-A11 cis-dicarba bond into either native insulin or the basal/long acting insulin glargine results in biased signalling analogues with low mitogenic potency. This can be attributed to reduced insulin receptor activation that prevents effective receptor internalization and mitogenic signalling. Insight gained into the receptor interactions affected by insertion of an A6-A11 cis-dicarba bond will ultimately assist in the development of new insulin analogues for the treatment of diabetes that confer low mitogenic activity and therefore pose minimal risk of promoting cancer with long term use.
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Affiliation(s)
- Shee Chee Ong
- Discipline of Medical Biochemistry, Flinders Health and Medical Research Institute, Flinders University of South Australia, Bedford Park, SA, Australia
| | - Alessia Belgi
- School of Chemistry, Monash University, Clayton, VIC, Australia
| | - Allanah L. Merriman
- Discipline of Medical Biochemistry, Flinders Health and Medical Research Institute, Flinders University of South Australia, Bedford Park, SA, Australia
| | - Carlie A. Delaine
- Discipline of Medical Biochemistry, Flinders Health and Medical Research Institute, Flinders University of South Australia, Bedford Park, SA, Australia
| | | | | | | | - Briony E. Forbes
- Discipline of Medical Biochemistry, Flinders Health and Medical Research Institute, Flinders University of South Australia, Bedford Park, SA, Australia
- *Correspondence: Briony E. Forbes,
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10
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Owens DR, Monnier L, Ceriello A, Bolli GB. Insulin Centennial: Milestones influencing the development of insulin preparations since 1922. Diabetes Obes Metab 2022; 24 Suppl 1:27-42. [PMID: 34708913 DOI: 10.1111/dom.14587] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 10/22/2021] [Accepted: 10/24/2021] [Indexed: 11/27/2022]
Abstract
During 1921 to 1922, a team effort by Banting, Macleod, Collip and Best isolated and purified insulin and demonstrated its life-giving properties, giving rise to the birth of insulin therapy. In the early years (1922-1950), priorities revolved around the manufacture of insulin to meet demand, improving purity to avoid allergic reactions, establishing insulin standards and increasing its duration of action to avoid multiple daily injections. Shortly after the emergence of insulin, Joslin and Allen advocated the need to achieve and maintain good glycaemic control to realize its full potential. Although this view was opposed by some during a dark period in the history of insulin, it was subsequently endorsed some 60 years later endorsed by the Diabetes Control and Complications Trial and United Kingdom Prospective Diabetes Study. Major scientific advances by the Nobel Laureates Sanger, Hodgkin, Yalow and Gilbert and also by Steiner have revolutionized the understanding of diabetes and facilitated major advances in insulin therapy. The more recent advent of recombinant technology over the last 40 years has provided the potential for unlimited source of insulin, and the ability to generate various insulin 'analogues', in an attempt to better replicate normal insulin secretory patterns. The emerging biosimilars now provide the opportunity to improve availability at a lower cost.
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Affiliation(s)
- David R Owens
- Diabetes Research Unit, University of Swansea Medical School, Wales, UK
| | - Louis Monnier
- Institute of Clinical Research, University of Montpellier, Montpellier, France
| | | | - Geremia B Bolli
- Department of Medicine, University of Perugia, Perugia, Italy
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11
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Bolli GB, Porcellati F, Lucidi P, Fanelli CG, Owens DR. One-hundred year evolution of prandial insulin preparations: From animal pancreas extracts to rapid-acting analogs. Metabolism 2022; 126:154935. [PMID: 34762931 DOI: 10.1016/j.metabol.2021.154935] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 10/26/2021] [Accepted: 11/04/2021] [Indexed: 11/23/2022]
Abstract
The first insulin preparation injected in humans in 1922 was short-acting, extracted from animal pancreas, contaminated by impurities. Ever since the insulin extracted from animal pancreas has been continuously purified, until an unlimited synthesis of regular human insulin (RHI) became possible in the '80s using the recombinant-DNA (rDNA) technique. The rDNA technique then led to the designer insulins (analogs) in the early '90s. Rapid-acting insulin analogs were developed to accelerate the slow subcutaneous (sc) absorption of RHI, thus lowering the 2-h post-prandial plasma glucose (PP-PG) and risk for late hypoglycemia as comparing with RHI. The first rapid-acting analog was lispro (in 1996), soon followed by aspart and glulisine. Rapid-acting analogs are more convenient than RHI: they improve early PP-PG, and 24-h PG and A1C as long as basal insulin is also optimized; they lower the risk of late PP hypoglycemia and they allow a shorter time-interval between injection and meal. Today rapid-acting analogs are the gold standard prandial insulins. Recently, even faster analogs have become available (faster aspart, ultra-rapid lispro) or are being studied (Biochaperone lispro), making additional gains in lowering PP-PG. Rapid-acting analogs are recommended in all those with type 1 and type 2 diabetes who need prandial insulin replacement.
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Affiliation(s)
- Geremia B Bolli
- Section of Endocrinology and Metabolism, Department of Medicine and Surgery, Perugia University School of Medicine, Perugia, Italy.
| | - Francesca Porcellati
- Section of Endocrinology and Metabolism, Department of Medicine and Surgery, Perugia University School of Medicine, Perugia, Italy
| | - Paola Lucidi
- Section of Endocrinology and Metabolism, Department of Medicine and Surgery, Perugia University School of Medicine, Perugia, Italy
| | - Carmine G Fanelli
- Section of Endocrinology and Metabolism, Department of Medicine and Surgery, Perugia University School of Medicine, Perugia, Italy
| | - David R Owens
- Diabetes Research Unit Cymru, University of Swansea Medical School, Singleton Park, Swansea SA2 8PP, Wales, United Kingdom
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12
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Jarosinski MA, Dhayalan B, Chen YS, Chatterjee D, Varas N, Weiss MA. Structural principles of insulin formulation and analog design: A century of innovation. Mol Metab 2021; 52:101325. [PMID: 34428558 PMCID: PMC8513154 DOI: 10.1016/j.molmet.2021.101325] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 08/12/2021] [Accepted: 08/17/2021] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND The discovery of insulin in 1921 and its near-immediate clinical use initiated a century of innovation. Advances extended across a broad front, from the stabilization of animal insulin formulations to the frontiers of synthetic peptide chemistry, and in turn, from the advent of recombinant DNA manufacturing to structure-based protein analog design. In each case, a creative interplay was observed between pharmaceutical applications and then-emerging principles of protein science; indeed, translational objectives contributed to a growing molecular understanding of protein structure, aggregation and misfolding. SCOPE OF REVIEW Pioneering crystallographic analyses-beginning with Hodgkin's solving of the 2-Zn insulin hexamer-elucidated general features of protein self-assembly, including zinc coordination and the allosteric transmission of conformational change. Crystallization of insulin was exploited both as a step in manufacturing and as a means of obtaining protracted action. Forty years ago, the confluence of recombinant human insulin with techniques for site-directed mutagenesis initiated the present era of insulin analogs. Variant or modified insulins were developed that exhibit improved prandial or basal pharmacokinetic (PK) properties. Encouraged by clinical trials demonstrating the long-term importance of glycemic control, regimens based on such analogs sought to resemble daily patterns of endogenous β-cell secretion more closely, ideally with reduced risk of hypoglycemia. MAJOR CONCLUSIONS Next-generation insulin analog design seeks to explore new frontiers, including glucose-responsive insulins, organ-selective analogs and biased agonists tailored to address yet-unmet clinical needs. In the coming decade, we envision ever more powerful scientific synergies at the interface of structural biology, molecular physiology and therapeutics.
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Affiliation(s)
- Mark A Jarosinski
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202, IN, USA
| | - Balamurugan Dhayalan
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202, IN, USA
| | - Yen-Shan Chen
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202, IN, USA
| | - Deepak Chatterjee
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202, IN, USA
| | - Nicolás Varas
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202, IN, USA
| | - Michael A Weiss
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, 46202, IN, USA; Department of Chemistry, Indiana University, Bloomington, 47405, IN, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, 47907, IN, USA.
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13
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Abstract
Insight into folding mechanisms of proinsulin has been provided by analysis of dominant diabetes-associated mutations in the human insulin gene (INS). Such mutations cause pancreatic β-cell dysfunction due to toxic misfolding of a mutant proinsulin and impairment in trans of wild-type insulin secretion. Anticipated by the "Akita" mouse (a classical model of monogenic diabetes mellitus; DM), this syndrome illustrates the paradigm endoreticulum (ER) stress leading to intracellular proteotoxicity. Diverse clinical mutations directly or indirectly perturb native disulfide pairing leading to protein misfolding and aberrant aggregation. Although most introduce or remove a cysteine (Cys; leading in either case to an unpaired thiol group), non-Cys-related mutations identify key determinants of folding efficiency. Studies of such mutations suggest that the hormone's evolution has been constrained not only by structure-function relationships, but also by the susceptibility of its single-chain precursor to impaired foldability. An intriguing hypothesis posits that INS overexpression in response to peripheral insulin resistance likewise leads to chronic ER stress and β-cell dysfunction in the natural history of non-syndromic Type 2 DM. Cryptic contributions of conserved residues to folding efficiency, as uncovered by rare genetic variants, define molecular links between biophysical principles and the emerging paradigm of Darwinian medicine: Biosynthesis of proinsulin at the edge of non-foldability provides a key determinant of "diabesity" as a pandemic disease of civilization.
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Affiliation(s)
| | | | | | - Michael A. Weiss
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
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14
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Dhayalan B, Chatterjee D, Chen YS, Weiss MA. Diabetes mellitus due to toxic misfolding of proinsulin variants. Mol Metab 2021:101229. [PMID: 33823319 DOI: 10.1016/j.molmet.2021.101229] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 03/10/2021] [Accepted: 03/29/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Dominant mutations in the human insulin gene (INS) lead to pancreatic β-cell dysfunction and diabetes mellitus (DM) due to toxic misfolding of a mutant proinsulin. Analogous to a classical mouse model of monogenic DM ("Akita"), this syndrome highlights the susceptibility of β-cells to endoreticulum (ER) stress due to protein misfolding and aberrant aggregation. SCOPE OF REVIEW Diverse clinical mutations directly or indirectly perturb native disulfide pairing. Whereas most introduce or remove a cysteine (Cys; leading in either case to an unpaired thiol group), non-Cys-related mutations identify key determinants of folding efficiency. Studies of such mutations suggest that the hormone's evolution has been constrained not only by structure-function relationships but also by the susceptibility of its single-chain precursor to impaired foldability. An intriguing hypothesis posits that INS overexpression in response to peripheral insulin resistance likewise leads to chronic ER stress and β-cell dysfunction in the natural history of nonsyndromic Type 2 DM. MAJOR CONCLUSIONS Cryptic contributions of conserved residues to folding efficiency, as uncovered by rare genetic variants, define molecular links between biophysical principles and the emerging paradigm of Darwinian medicine: Biosynthesis of proinsulin at the edge of nonfoldability provides a key determinant of "diabesity" as a pandemic disease of civilization.
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Affiliation(s)
- Balamurugan Dhayalan
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Deepak Chatterjee
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Yen-Shan Chen
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Michael A Weiss
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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15
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Abstract
Ligand bias is the ability of ligands to differentially activate certain receptor signaling responses compared with others. It reflects differences in the responses of a receptor to specific ligands and has implications for the development of highly specific therapeutics. Whereas ligand bias has been studied primarily for G protein-coupled receptors (GPCRs), there are also reports of ligand bias for receptor tyrosine kinases (RTKs). However, the understanding of RTK ligand bias is lagging behind the knowledge of GPCR ligand bias. In this review, we highlight how protocols that were developed to study GPCR signaling can be used to identify and quantify RTK ligand bias. We also introduce an operational model that can provide insights into the biophysical basis of RTK activation and ligand bias. Finally, we discuss possible mechanisms underpinning RTK ligand bias. Thus, this review serves as a primer for researchers interested in investigating ligand bias in RTK signaling.
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Affiliation(s)
- Kelly Karl
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, and Program in Molecular Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Michael D Paul
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, and Program in Molecular Biophysics, Johns Hopkins University, Baltimore, Maryland, USA
| | - Elena B Pasquale
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA.
| | - Kalina Hristova
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, and Program in Molecular Biophysics, Johns Hopkins University, Baltimore, Maryland, USA.
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16
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Affiliation(s)
- Anne Kilvert
- Consultant Physician, Northampton Community Diabetes Team UK
| | - Charles Fox
- Honorary Lecturer, Leicester Diabetes Centre Leicester UK
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17
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Liu Y, Wang HY, Shao J, Zaro JL, Shen WC. Enhanced insulin receptor interaction by a bifunctional insulin-transferrin fusion protein: an approach to overcome insulin resistance. Sci Rep 2020; 10:7724. [PMID: 32382087 DOI: 10.1038/s41598-020-64731-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 01/03/2020] [Indexed: 01/01/2023] Open
Abstract
Bifunctional fusion protein design has been widely utilized as a strategy to increase the efficacy of protein therapeutics. Previously, we proposed a novel application of the bifunctional fusion protein design through the introduction of proinsulin-transferrin (ProINS-Tf) fusion protein as a liver-specific protein prodrug to achieve a glucose-lowering effect in type 1 diabetic mice. In this report, we studied the binding characteristics of this activated fusion protein to the insulin receptor to elucidate its mechanism in eliciting insulin receptor-mediated signaling. We found that, with the assistance of the transferrin moiety binding to the transferrin receptor, the activated ProINS-Tf exhibited significantly higher binding affinity to the insulin receptor compared with the native insulin, resulting in a prolonged and stronger Akt phosphorylation. This enhanced induction by activated ProINS-Tf overcame insulin resistance in palmitate-treated HepG2 cells. ProINS-Tf also demonstrated a better glucose-lowering effect than native insulin, even with a much lower dose and less frequent injections, in non-obese diabetic mice with insulin resistance symptoms. The activated ProINS-Tf, serving as a bivalent protein molecule, could be a new insulin analog to overcome insulin resistance, which is associated with several diseases, including type 2 diabetes and non-alcoholic fatty liver disease.
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18
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Rege NK, Liu M, Dhayalan B, Chen YS, Smith NA, Rahimi L, Sun J, Guo H, Yang Y, Haataja L, Phillips NFB, Whittaker J, Smith BJ, Arvan P, Ismail-Beigi F, Weiss MA. "Register-shift" insulin analogs uncover constraints of proteotoxicity in protein evolution. J Biol Chem 2020; 295:3080-3098. [PMID: 32005662 DOI: 10.1074/jbc.ra119.011389] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 01/27/2020] [Indexed: 12/16/2022] Open
Abstract
Globular protein sequences encode not only functional structures (the native state) but also protein foldability, i.e. a conformational search that is both efficient and robustly minimizes misfolding. Studies of mutations associated with toxic misfolding have yielded insights into molecular determinants of protein foldability. Of particular interest are residues that are conserved yet dispensable in the native state. Here, we exploited the mutant proinsulin syndrome (a major cause of permanent neonatal-onset diabetes mellitus) to investigate whether toxic misfolding poses an evolutionary constraint. Our experiments focused on an invariant aromatic motif (PheB24-PheB25-TyrB26) with complementary roles in native self-assembly and receptor binding. A novel class of mutations provided evidence that insulin can bind to the insulin receptor (IR) in two different modes, distinguished by a "register shift" in this motif, as visualized by molecular dynamics (MD) simulations. Register-shift variants are active but defective in cellular foldability and exquisitely susceptible to fibrillation in vitro Indeed, expression of the corresponding proinsulin variant induced endoplasmic reticulum stress, a general feature of the mutant proinsulin syndrome. Although not present among vertebrate insulin and insulin-like sequences, a prototypical variant ([GlyB24]insulin) was as potent as WT insulin in a rat model of diabetes. Although in MD simulations the shifted register of receptor engagement is compatible with the structure and allosteric reorganization of the IR-signaling complex, our results suggest that this binding mode is associated with toxic misfolding and so is disallowed in evolution. The implicit threat of proteotoxicity limits sequence variation among vertebrate insulins and insulin-like growth factors.
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Affiliation(s)
- Nischay K Rege
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Ming Liu
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical Center, Ann Arbor, Michigan 48105, Australia; Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, Heping District, 300052 China
| | - Balamurugan Dhayalan
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Yen-Shan Chen
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Nicholas A Smith
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Leili Rahimi
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106
| | - Jinhong Sun
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical Center, Ann Arbor, Michigan 48105, Australia
| | - Huan Guo
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical Center, Ann Arbor, Michigan 48105, Australia
| | - Yanwu Yang
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202
| | - Leena Haataja
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical Center, Ann Arbor, Michigan 48105, Australia
| | - Nelson F B Phillips
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Jonathan Whittaker
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Brian J Smith
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Peter Arvan
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical Center, Ann Arbor, Michigan 48105, Australia
| | - Faramarz Ismail-Beigi
- Department of Biochemistry, Case Western Reserve University, Cleveland, Ohio 44106; Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106
| | - Michael A Weiss
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana 46202.
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19
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Ahorukomeye P, Disotuar MM, Gajewiak J, Karanth S, Watkins M, Robinson SD, Flórez Salcedo P, Smith NA, Smith BJ, Schlegel A, Forbes BE, Olivera B, Hung-Chieh Chou D, Safavi-Hemami H. Fish-hunting cone snail venoms are a rich source of minimized ligands of the vertebrate insulin receptor. eLife 2019; 8:41574. [PMID: 30747102 PMCID: PMC6372279 DOI: 10.7554/elife.41574] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 12/30/2018] [Indexed: 12/27/2022] Open
Abstract
The fish-hunting marine cone snail Conus geographus uses a specialized venom insulin to induce hypoglycemic shock in its prey. We recently showed that this venom insulin, Con-Ins G1, has unique characteristics relevant to the design of new insulin therapeutics. Here, we show that fish-hunting cone snails provide a rich source of minimized ligands of the vertebrate insulin receptor. Insulins from C. geographus, Conus tulipa and Conus kinoshitai exhibit diverse sequences, yet all bind to and activate the human insulin receptor. Molecular dynamics reveal unique modes of action that are distinct from any other insulins known in nature. When tested in zebrafish and mice, venom insulins significantly lower blood glucose in the streptozotocin-induced model of diabetes. Our findings suggest that cone snails have evolved diverse strategies to activate the vertebrate insulin receptor and provide unique insight into the design of novel drugs for the treatment of diabetes. Insulin is a hormone critical for maintaining healthy blood sugar levels in humans. When the insulin system becomes faulty, blood sugar levels become too high, which can lead to diabetes. At the moment, the only effective treatment for one of the major types of diabetes are daily insulin injections. However, designing fast-acting insulin drugs has remained a challenge. Insulin molecules form clusters (so-called hexamers) that first have to dissolve in the body to activate the insulin receptor, which plays a key role in regulating the blood sugar levels throughout the body. This can take time and can therefore delay the blood-sugar control. In 2015, researchers discovered that the fish-hunting cone snail Conus geographus uses a specific type of insulin to capture its prey – fish. The cone snail releases insulin into the surrounding water and then engulfs its victim with its mouth. This induces dangerously low blood sugar levels in the fish and so makes them an easy target. Unlike the human version, the snail insulin does not cluster, and despite structural differences, can bind to the human insulin receptor. Now, Ahorukomeye, Disotuar et al. – including some of the authors involved in the previous study – wanted to find out whether other fish-hunting cone snails also make insulins and if they differed from the one previously discovered in C. geographus. The insulin molecules were extracted and analyzed, and the results showed that the three cone snail species had different versions of insulin – but none of them formed clusters. Ahorukomeye, Disotuar et al. further revealed that the snail insulins could bind to the human insulin receptors and could also reverse high blood sugar levels in fish and mouse models of the disease. This research may help guide future studies looking into developing fast-acting insulin drugs for diabetic patients. A next step will be to fully understand how snail insulins can be active at the human receptor without forming clusters. Cone snails solved this problem millions of years ago and by understanding how they have done this, researchers are hoping to redesign current diabetic therapeutics. Since the snail insulins do not form clusters and should act faster than currently available insulin drugs, they may lead to better or new diabetes treatments.
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Affiliation(s)
- Peter Ahorukomeye
- Department of Biology, University of Utah School of Medicine, Salt Lake City, United States
| | - Maria M Disotuar
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
| | - Joanna Gajewiak
- Department of Biology, University of Utah School of Medicine, Salt Lake City, United States
| | - Santhosh Karanth
- Molecular Medicine Program, University of Utah, Salt Lake City, United States.,Department of Internal Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, United States.,Department of Nutrition and Integrative Physiology, College of Health, University of Utah, Salt Lake City, United States
| | - Maren Watkins
- Department of Biology, University of Utah School of Medicine, Salt Lake City, United States
| | - Samuel D Robinson
- Department of Biology, University of Utah School of Medicine, Salt Lake City, United States
| | - Paula Flórez Salcedo
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
| | - Nicholas A Smith
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Brian J Smith
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Amnon Schlegel
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States.,Molecular Medicine Program, University of Utah, Salt Lake City, United States.,Department of Internal Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Utah School of Medicine, Salt Lake City, United States.,Department of Nutrition and Integrative Physiology, College of Health, University of Utah, Salt Lake City, United States
| | - Briony E Forbes
- Department of Medical Biochemistry, Flinders University, Bedford Park, Australia
| | - Baldomero Olivera
- Department of Biology, University of Utah School of Medicine, Salt Lake City, United States
| | - Danny Hung-Chieh Chou
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
| | - Helena Safavi-Hemami
- Department of Biology, University of Utah School of Medicine, Salt Lake City, United States.,Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
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20
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Abstract
BACKGROUND Diabetes has recently been identified as a risk factor for a variety of cancers, possibly due to hyperinsulinemia or exogenous insulin use. Thyroid cancer is the most common endocrine malignancy, and its incidence has been exponentially increasing worldwide at an alarming rate. The aim of this study was to establish whether insulin use affects thyroid cancer development and progression, specifically cell proliferation and migration in vitro. METHODS In this study, we investigated the effects of the insulin agents most commonly used in the clinic, regular human insulin (HI) and insulin glargine (IG), on the proliferation and migration of thyroid cells. RESULTS Both HI and IG affected the thyroid cells in a dose-dependent manner and at high concentrations significantly promoted thyroid cell proliferation and tumor cell migration. The promoting effect might be elicited by activation of the insulin receptor and insulin-like growth factor-1 receptor and through the downstream Akt-signaling pathway, which inhibits the activity of the tumor-suppressor FoxO3a. In particular, MAPK-signaling cascades were activated in papillary thyroid carcinoma cell-1 cells but not in follicular rat thyroid-5 cells. CONCLUSION The in vitro evidence demonstrated that HI and IG can promote thyroid cell proliferation and tumor cell migration at supraphysiological concentrations, but the effect was not significant at low concentrations. Whether high-dose insulins could affect diabetic patients with thyroid cancer or undetected (pre)cancerous lesions needs further in vivo study. ABBREVIATIONS HI: human regular insulin; IG: insulin glargine; IR: insulin receptor; IGF-1R: insulin-like growth factor-1 receptor; Akt: protein kinase B (PKB); MAPK: mitogen-activated protein kinase; FoxO3a: the forkhead box-containing protein: class O 3a.
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Affiliation(s)
- Xinxia Zhang
- a Department of Geriatrics , The First Affiliated Hospital, College of Medicine, Zhejiang University , Hangzhou , Zhejiang , China
| | - Xiaoli Sheng
- b Department of Obstetrics , The First Affiliated Hospital, College of Medicine, Zhejiang University , Hangzhou , Zhejiang , China
| | - Tingru Miao
- c ECG Functional Department , Zhejiang Province People's Hospital , Hangzhou , Zhejiang , China
| | - Kannan Yao
- d The Second Central Laboratory , The First Affiliated Hospital of Zhejiang Chinese Medical University , Hangzhou , Zhejiang , China
| | - Dingguo Yao
- e Department of Endocrinology , The First Affiliated Hospital of Zhejiang Chinese Medical University , Hangzhou , Zhejiang , China
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Sheng X, Yao K, Shao A, Tu S, Zhang X, Chen T, Yao D. The Role of Insulin Glargine and Human Insulin in the Regulation of Thyroid Proliferation Through Mitogenic Signaling. Front Endocrinol (Lausanne) 2019; 10:594. [PMID: 31555212 PMCID: PMC6723759 DOI: 10.3389/fendo.2019.00594] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 08/13/2019] [Indexed: 12/29/2022] Open
Abstract
Our aim was to investigate whether human insulin (HI) or insulin glargine treatment could promote the proliferation of thyroid cells and determine the association between type 2 diabetes and thyroid disease. Rats were treated with different doses of HI and insulin glargine. Plasma glucose and the phosphorylation levels of the insulin receptor (IR), insulin-like growth factor 1 receptor (IGF-1R), protein kinase B (Akt), and extracellular signal-regulated kinase 1/2 (ERK1/2) were measured. A total of 105 rats were randomly assigned to three groups as follows: control group, HI group, and glargine group. Both drugs promoted the phosphorylation of IR, Akt, and ERK1/2 in a dose-dependent manner (p < 0.05), and the effect of glargine persisted for longer period. Treatment with ultra-therapeutic doses of HI or glargine (p < 0.05) increased the expression of Ki-67 in thyroid cells. The results demonstrated that therapeutic doses of glargine have a longer-lasting hypoglycemic control than HI. Based on the results, HI or glargine did not stimulate thyroid cell proliferation at therapeutic doses, but high doses did.
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Affiliation(s)
- Xiaoli Sheng
- Department of Obstetrics, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Kannan Yao
- The Second Central Laboratory, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Anwen Shao
- Department of Neurosurgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Sheng Tu
- Department of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- *Correspondence: Sheng Tu
| | - Xinxia Zhang
- Department of Geriatrics, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Ting Chen
- Department of Ultrasonography, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
| | - Dingguo Yao
- Department of Endocrinology, The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, China
- Dingguo Yao
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Abstract
There have been many advances in insulin with a realistic possibility of mimicking nature to improve insulin replacement, with a view to achieving improved metabolic control. Lessons can be learnt from the evolution of insulin, insulin development, and new advances in technology. This may lead to fewer side effects of therapy resulting in a lower risk of hypoglycaemia and less weight gain, which could in turn could reduce long-term complications for people with diabetes.
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Affiliation(s)
- R Herring
- Royal Surrey County NHS Foundation Hospital, Guildford, UK
- University of Surrey, Guildford, Surrey, UK
| | - D D L Russell-Jones
- Royal Surrey County NHS Foundation Hospital, Guildford, UK
- University of Surrey, Guildford, Surrey, UK
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Mori Y, Ko E, Furrer R, Qu LC, Wiber SC, Fantus IG, Thevis M, Medline A, Giacca A. Effects of insulin and analogues on carcinogen-induced mammary tumours in high-fat-fed rats. Endocr Connect 2018; 7:739-748. [PMID: 29692348 PMCID: PMC5958747 DOI: 10.1530/ec-17-0358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 04/24/2018] [Indexed: 12/29/2022]
Abstract
It is not fully clarified whether insulin glargine, an analogue with a high affinity for insulin-like growth factor-1 receptor (IGF-1R), increases the risk for cancers that abundantly express IGF-1R such as breast cancer or some types of breast cancer. To gain insight into this issue, female Sprague-Dawley rats fed a high-fat diet were given the carcinogen N-methyl-N-nitrosourea and randomly assigned to vehicle (control), NPH (unmodified human insulin), glargine or detemir (n = 30 per treatment). Insulins were given subcutaneously (15 U/kg/day) 5 days a week. Mammary tumours were counted twice weekly, and after 6 weeks of treatment, extracted for analysis. None of the insulin-treated groups had increased mammary tumour incidence at any time compared with control. At 6 weeks, tumour multiplicity was increased with NPH or glargine (P < 0.05) and tended to be increased with detemir (P = 0.2); however, there was no difference among insulins (number of tumours per rat: control = 0.8 ± 0.1, NPH = 1.8 ± 0.3, glargine = 1.5 ± 0.4, detemir = 1.4 ± 0.4; number of tumours per tumour-bearing rat: control = 1.3 ± 0.1, NPH = 2.2 ± 0.4, glargine = 2.7 ± 0.5, detemir = 2.3 ± 0.5). IGF-1R expression in tumours was lower than that in Michigan Cancer Foundation-7 (MCF-7) cells, a cell line that shows greater proliferation with glargine than unmodified insulin. In rats, glargine was rapidly metabolised to M1 that does not have greater affinity for IGF-1R. In conclusion, in this model of oestrogen-dependent breast cancer in insulin-resistant rats, insulin and insulin analogues increased tumour multiplicity with no difference between insulin types.
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Affiliation(s)
- Yusaku Mori
- Department of PhysiologyFaculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of DiabetesMetabolism, and Endocrinology, Showa University School of Medicine, Shinagawa, Tokyo, Japan
| | - Eunhyoung Ko
- Department of PhysiologyFaculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Rudolf Furrer
- Department of Nutritional SciencesFaculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Linda C Qu
- Department of PhysiologyFaculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Stuart C Wiber
- Department of PhysiologyFaculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - I George Fantus
- Departments of Medicine and PhysiologyFaculty of Medicine, University of Toronto, Toronto, Ontario, Canada
- Toronto General Research InstituteUniversity Health Network, Toronto, Ontario, Canada
- Division of Endocrinology and MetabolismLeadership Centre for Diabetes, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Mario Thevis
- Center for Preventive Doping Research and Institute of BiochemistryGerman Sport University Cologne, Cologne, Germany
| | - Alan Medline
- Department of Laboratory Medicine & PathobiologyUniversity of Toronto, Toronto, Ontario, Canada
- Department of PathologyHumber River Regional Hospital, Toronto, Ontario, Canada
| | - Adria Giacca
- Departments of Physiology and MedicineInstitute of Medical Science, Banting and Best Diabetes Centre, University of Toronto, Toronto, Ontario, Canada
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Takahashi H, Nishimura R, Onda Y, Ando K, Tsujino D, Utsunomiya K. Comparison of glycemic variability in Japanese patients with type 1 diabetes receiving insulin degludec versus insulin detemir using continuous glucose monitoring: a randomized, cross-over, pilot study. Expert Opin Pharmacother 2017; 18:335-342. [PMID: 28234565 DOI: 10.1080/14656566.2017.1293652] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To use continuous glucose monitoring (CGM) to compare glycemic variability in patients with type 1 diabetes (T1D) treated with insulin degludec (IDeg) versus insulin detemir (IDet). METHODS Ten patients with T1D were randomly assigned to receive once-daily IDeg, followed by twice-daily IDet, or vice versa. Glucose variability was evaluated by CGM after >4 weeks of the first insulin and again after crossover to the second insulin. RESULTS The total daily insulin dose (U/kg/day) and the total daily basal insulin dose (U/kg/day) were significantly lower during treatment with IDeg than with IDet [median (interquartile range): 0.55 (0.54-0.73) vs. 0.64 (0.54-0.83); P = 0.028, 0.24 (0.19-0.36) vs. 0.30 (0.19-0.39); P = 0.027]. The 24-hour mean glucose levels were not significantly different. However, their standard deviation (SD) was significantly smaller during treatments with IDeg than those with IDet [59.5 (39.5-71.0) vs. 72.8 (61.8-92.8); P = 0.008]. Their mean fasting glucose levels and the mean postprandial peak levels after breakfast and after dinner were significantly lower with IDeg. CONCLUSIONS A CGM-based comparison demonstrated that once-daily IDeg showed fewer glycemic fluctuations than twice-daily IDet. IDeg appears to stabilize blood glucose levels better during both daytime and nighttime (particularly, before and after breakfast) with a lower insulin dosage.
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Affiliation(s)
- Hiroshi Takahashi
- a Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine , Jikei University School of Medicine , Tokyo , Japan
| | - Rimei Nishimura
- a Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine , Jikei University School of Medicine , Tokyo , Japan.,b Graduate School of Public Health , University of Pittsburgh , Pittsburgh , PA , USA
| | - Yoshiko Onda
- a Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine , Jikei University School of Medicine , Tokyo , Japan
| | - Kiyotaka Ando
- a Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine , Jikei University School of Medicine , Tokyo , Japan
| | - Daisuke Tsujino
- a Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine , Jikei University School of Medicine , Tokyo , Japan
| | - Kazunori Utsunomiya
- a Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine , Jikei University School of Medicine , Tokyo , Japan
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Owens RA, Hansen RJ, Kahl SD, Zhang C, Ruan X, Koester A, Li S, Qian HR, Farmen MW, Michael MD, Moyers JS, Cutler GB, Vick A, Beals JM. In Vivo and In Vitro Characterization of Basal Insulin Peglispro: A Novel Insulin Analog. ACTA ACUST UNITED AC 2016; 357:459-65. [DOI: 10.1124/jpet.115.231035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 03/22/2016] [Indexed: 11/22/2022]
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Bedinger DH, Adams SH. Metabolic, anabolic, and mitogenic insulin responses: A tissue-specific perspective for insulin receptor activators. Mol Cell Endocrinol 2015; 415:143-56. [PMID: 26277398 DOI: 10.1016/j.mce.2015.08.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Revised: 08/05/2015] [Accepted: 08/09/2015] [Indexed: 12/17/2022]
Abstract
Insulin acts as the major regulator of the fasting-to-fed metabolic transition by altering substrate metabolism, promoting energy storage, and helping activate protein synthesis. In addition to its glucoregulatory and other metabolic properties, insulin can also act as a growth factor. The metabolic and mitogenic responses to insulin are regulated by divergent post-receptor signaling mechanisms downstream from the activated insulin receptor (IR). However, the anabolic and growth-promoting properties of insulin require tissue-specific inter-relationships between the two pathways, and the nature and scope of insulin-regulated processes vary greatly across tissues. Understanding the nuances of this interplay between metabolic and growth-regulating properties of insulin would have important implications for development of novel insulin and IR modulator therapies that stimulate insulin receptor activation in both pathway- and tissue-specific manners. This review will provide a unique perspective focusing on the roles of "metabolic" and "mitogenic" actions of insulin signaling in various tissues, and how these networks should be considered when evaluating selective pharmacologic approaches to prevent or treat metabolic disease.
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Affiliation(s)
| | - Sean H Adams
- Arkansas Children's Nutrition Center and University of Arkansas for Medical Sciences, Department of Pediatrics, Little Rock, AR, USA
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Kobuke K, Yoneda M, Nakanishi S, Ohno H, Maeda S, Egusa G. Efficacy and safety of insulin degludec in Japanese patients with type 1 and type 2 diabetes: 24-week results from the observational study in routine clinical practice. J Diabetes Investig 2015; 7:94-9. [PMID: 26816606 PMCID: PMC4718095 DOI: 10.1111/jdi.12373] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/17/2015] [Accepted: 05/07/2015] [Indexed: 02/03/2023] Open
Abstract
Aims/Introduction Insulin degludec, a new long‐acting insulin analog, showed its better glycemic control and reduced risk of hypoglycemia. This is the first prospective observational study that evaluated the efficacy and safety of insulin degludec in routine clinical practice. Materials and Methods Japanese patients with type 1 or type 2 diabetes mellitus receiving basal–bolus insulin therapy were switched their basal insulin to degludec, and prospectively observed over a 24‐week course. The Diabetes Therapy‐Related Quality of Life questionnaire was administered before and 12 weeks after switching. Results The participants were 80 diabetes patients = (type 1, 44; type 2, 36). In the type 1 group, there was no difference in glycated hemoglobin levels between the pre‐switching and 24‐week measurements (from 62 to 62 mmol/mol, P = 0.768), whereas the daily insulin dose (per kg of bodyweight) decreased significantly (basal, from 0.25 to 0.20 U/kg, P < 0.001; bolus, from 0.40 to 0.37 U/kg, P = 0.001). In the type 2 group, glycated hemoglobin levels decreased after switching (from 60 to 58 mmol/mol, P = 0.028). In the type 1 group, the frequency of hypoglycemia decreased significantly after switching, but not significantly in the type 2 group. Patient satisfaction with the control of hypoglycemia tended to improve in the type 1 group. Conclusions Compared with existing long‐acting insulin, degludec can maintain glycemic control at a lower insulin dose and frequency of hypoglycemia in type 1 diabetes, while it can improve glycemic control at an equal insulin dose in type 2 diabetes. This is first observational prospective study of insulin degludec in routine clinical practice that we evaluated the effect on glycemic control and risk of hypoglycemia in basal‐bolus insulin therapy. We found that insulin degludec can maintain glycemic control at a lower insulin dose and frequency of hypoglycemia in type 1 diabetes, while it can improve glycemic control at equally insulin dose in type 2 diabetes. These results mean that insulin degludec is of use in routine clinical practice.
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Affiliation(s)
- Kazuhiro Kobuke
- Department of Molecular and Internal Medicine Graduate School of Biomedical & Health Sciences Hiroshima University Hiroshima Japan
| | - Masayasu Yoneda
- Department of Molecular and Internal Medicine Graduate School of Biomedical & Health Sciences Hiroshima University Hiroshima Japan
| | - Shuhei Nakanishi
- Department of Metabolism and Endocrinology Hiroshima Red Cross Hospital & Atomic Bomb Survivors Hospital Hiroshima Japan
| | - Haruya Ohno
- Department of Molecular and Internal Medicine Graduate School of Biomedical & Health Sciences Hiroshima University Hiroshima Japan
| | - Shusaku Maeda
- Department of Molecular and Internal Medicine Graduate School of Biomedical & Health Sciences Hiroshima University Hiroshima Japan
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Baricevic I, Jones DR, Roberts DL, Lutzen A, Lundby A, Worm J, Hansen BF, Renehan AG. A framework for the in vitro evaluation of cancer-relevant molecular characteristics and mitogenic potency of insulin analogues. Carcinogenesis 2015; 36:1040-50. [PMID: 26026165 PMCID: PMC4552242 DOI: 10.1093/carcin/bgv071] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2014] [Accepted: 04/16/2015] [Indexed: 12/28/2022] Open
Abstract
Clinically prescribed insulin analogues are putatively linked with increased cancer risk. We developed a framework for the mandated regulatory in vitro evaluation of cancer-relevant bioassays for comparisons of insulin analogues, and showed that the cell-specific IGF-IR/IR ratio is crucial for interpretation. Epidemiological and laboratory studies raise the possibility of a link between clinically prescribed insulin analogues and increased cancer risk. Accordingly, there is a regulatory mandate for cancer-related pre-clinical safety evaluation during insulin analogue development, but currently, there is no standardized framework for such in vitro evaluation. We tested human insulin; the super-mitogenic insulin, X10 and insulin-like growth factor I, in four cancer cell lines with a range of insulin-like growth factor-I receptor (IGF-IR)/IR (insulin receptor) ratios (HCT 116, HT-29, COLO 205 and MCF7) and related these to IGF-IR and IR expression in 17 human adenocarcinomas. All cell types were IR-A isoform dominant. We determined IGF-IR/IR signalling pathway endpoints in dose- and time-varying experiments, and performed mitogenic dose–response equivalent assays to derive EC50 values, and correlated these with IGF-IR/IR ratios. We superimposed relative EC50 values onto data from the literature in a meta-analysis. The IGF-IR/IR ratios varied from <1 to 12 in the selected cell lines; similar pattern ranges were observed in human adenocarcinomas. The three ligands demonstrated differential IR/IGF-IR and Akt phosphorylation, which correlated with cell-specific IGF-IR/IR ratios. Mitogenic profiles of X10 mimicked those for insulin-like growth factor I (IGF-I) and correlated with IGF-IR/IR ratios. The meta-analysis, adding data from five additional studies, supported the hypothesis that ligand mitogenic potency, relative to human insulin, increases with increasing cell-specific IGF-IR/IR ratio. This study established a framework for the in vitro evaluation of cancer-relevant bioassays for comparisons of insulin analogues, and specifically consolidated earlier studies that determination of the cell-specific IGF-IR/IR ratio is crucial for the interpretation of ranking relative biological activities.
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Affiliation(s)
- Ivona Baricevic
- Faculty Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK, Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - David R Jones
- Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and
| | - Darren L Roberts
- Faculty Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK, Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Anne Lutzen
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Anders Lundby
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Jesper Worm
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Bo F Hansen
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
| | - Andrew G Renehan
- Faculty Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, University of Manchester, Wilmslow Road, Manchester M20 4BX, UK, Inositide Laboratory, Cancer Research UK Manchester Institute, Paterson Building, Manchester M20 4BX, UK and Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark
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Engholm E, Hansen TH, Johansson E, Strauss HM, Vinther TN, Jensen KJ, Hubálek F, Kjeldsen TB. Expression, Receptor Binding, and Biophysical Characterization of Guinea Pig Insulin desB30: A Monomeric Insulin Variant. Chembiochem 2015; 16:954-8. [DOI: 10.1002/cbic.201402688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Indexed: 11/06/2022]
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Bedinger DH, Goldfine ID, Corbin JA, Roell MK, Adams SH. Differential pathway coupling of the activated insulin receptor drives signaling selectivity by XMetA, an allosteric partial agonist antibody. J Pharmacol Exp Ther 2015; 353:35-43. [PMID: 25613982 DOI: 10.1124/jpet.114.221309] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The monoclonal antibody XMetA is an allosteric partial agonist of the insulin receptor (IR), which activates the metabolic Akt kinase signaling pathway while having little or no effect on the mitogenic extracellular signal-regulated kinase (ERK) signaling pathway. To investigate the nature of this selective signaling, we have conducted a detailed investigation of XMetA to evaluate specific phosphorylation and activation of IR, Akt, and ERK in Chinese hamster ovary cell lines expressing either the short or long isoform of the human IR. Insulin activated both pathways, but the phosphorylation of Akt was more sensitive to the hormone than the phosphorylation of ERK. Maximally effective concentrations of XMetA elicited phosphorylation patterns similar to 40-100 pM insulin, which were sufficient for robust Akt phosphorylation, but had little effect on ERK phosphorylation. These data indicate that the preferential signaling of XMetA is due to an innate difference in pathway sensitivity of Akt versus ERK responses to IR activation and partial agonism by XMetA, rather than a separate pathway-biased mechanism. The metabolic selectivity of partial IR agonists like XMetA, if recapitulated in vivo, may be a desirable feature of therapeutic agents designed to regulate blood glucose levels while minimizing undesirable outcomes of excessive IR mitogenic activation.
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Affiliation(s)
- Daniel H Bedinger
- XOMA Corporation, Berkeley, California (D.H.B., I.D.G., J.A.C., M.K.R.); Obesity & Metabolism Research Unit, United States Department of Agriculture-Agricultural Research Service Western Human Nutrition Research Center and Department of Nutrition, Davis, California (S.H.A.); and Molecular, Cellular and Integrative Physiology Graduate Group, University of California at Davis, Davis, California (D.H.B., S.H.A.)
| | - Ira D Goldfine
- XOMA Corporation, Berkeley, California (D.H.B., I.D.G., J.A.C., M.K.R.); Obesity & Metabolism Research Unit, United States Department of Agriculture-Agricultural Research Service Western Human Nutrition Research Center and Department of Nutrition, Davis, California (S.H.A.); and Molecular, Cellular and Integrative Physiology Graduate Group, University of California at Davis, Davis, California (D.H.B., S.H.A.)
| | - John A Corbin
- XOMA Corporation, Berkeley, California (D.H.B., I.D.G., J.A.C., M.K.R.); Obesity & Metabolism Research Unit, United States Department of Agriculture-Agricultural Research Service Western Human Nutrition Research Center and Department of Nutrition, Davis, California (S.H.A.); and Molecular, Cellular and Integrative Physiology Graduate Group, University of California at Davis, Davis, California (D.H.B., S.H.A.)
| | - Marina K Roell
- XOMA Corporation, Berkeley, California (D.H.B., I.D.G., J.A.C., M.K.R.); Obesity & Metabolism Research Unit, United States Department of Agriculture-Agricultural Research Service Western Human Nutrition Research Center and Department of Nutrition, Davis, California (S.H.A.); and Molecular, Cellular and Integrative Physiology Graduate Group, University of California at Davis, Davis, California (D.H.B., S.H.A.)
| | - Sean H Adams
- XOMA Corporation, Berkeley, California (D.H.B., I.D.G., J.A.C., M.K.R.); Obesity & Metabolism Research Unit, United States Department of Agriculture-Agricultural Research Service Western Human Nutrition Research Center and Department of Nutrition, Davis, California (S.H.A.); and Molecular, Cellular and Integrative Physiology Graduate Group, University of California at Davis, Davis, California (D.H.B., S.H.A.)
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Lundby A, Bolvig P, Hegelund AC, Hansen BF, Worm J, Lützen A, Billestrup N, Bonnesen C, Oleksiewicz MB. Surface-expressed insulin receptors as well as IGF-I receptors both contribute to the mitogenic effects of human insulin and its analogues. J Appl Toxicol 2014; 35:842-50. [DOI: 10.1002/jat.3082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 09/13/2014] [Accepted: 09/15/2014] [Indexed: 11/09/2022]
Affiliation(s)
- Anders Lundby
- Department of Biomedical Sciences; University of Copenhagen; Blegdamsvej 3 2200 Copenhagen N Denmark
| | - Pernille Bolvig
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | | | - Bo F. Hansen
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Jesper Worm
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Anne Lützen
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Nils Billestrup
- Department of Biomedical Sciences; University of Copenhagen; Blegdamsvej 3 2200 Copenhagen N Denmark
| | - Christine Bonnesen
- Diabetes Research Unit, Novo Nordisk A/S; Novo Nordisk Park 2760 Maaloev Denmark
| | - Martin B. Oleksiewicz
- Centre for Biosecurity and Biopreparedness; Statens Serum Institute; Artillerivej 5 2300 Copenhagen S Denmark
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Abstract
CONTEXT Insulin glargine (GLA) is rapidly metabolized in vivo to metabolite M1, which has in vitro metabolic and mitogenic profiles comparable with human insulin (HI). OBJECTIVE To investigate the pharmacologic and signalling profiles of a non-metabolizable analogue (A21Gly,DiD-Arg) insulin (D-GLA). METHODS Rats were injected s.c. with 1, 12.5 or 200 U/kg of GLA or D-GLA; blood glucose and phosphorylation status of the insulin receptor (IR), Akt and IGF-1 receptor (IGF1R) in tissue samples were investigated after 1 h. Plasma samples were analysed for insulin by LC-MS/MS. RESULTS Blood glucose lowering was prolonged with D-GLA. D-GLA comprised ≥98% of insulin after D-GLA injection; M1 comprised 76-92% after GLA injection. IR and Akt phosphorylation were comparable with GLA and D-GLA. Neither analogue stimulated IGF1R phosphorylation. CONCLUSIONS Suprapharmacological doses of D-GLA did not activate IGF1R in vivo. Mitogenic effects of insulin and insulin analogues might be solely based on IR growth-promoting activity.
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Svendsen AM, Winge SB, Zimmermann M, Lindvig AB, Warzecha CB, Sajid W, Horne MC, De Meyts P. Down-regulation of cyclin G2 by insulin, IGF-I (insulin-like growth factor 1) and X10 (AspB10 insulin): role in mitogenesis. Biochem J. 2014;457:69-77. [PMID: 24059861 DOI: 10.1042/BJ20130490] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The mechanisms whereby insulin analogues may cause enhanced mitogenicity through activation of either the IR (insulin receptor) or the IGF-IR (insulin-like growth factor 1 receptor) are incompletely understood. We demonstrate that in L6 myoblasts expressing only IGF-IRs as well as in the same cells overexpressing the IR, IGF-I (insulin-like growth factor 1), insulin and X10 (AspB10 insulin) down-regulate the mRNA expression level of the cell cycle inhibitor cyclin G2, as measured by qRT-PCR (quantitative reverse transcription-PCR), and induce cell growth measured by [6-(3)H]thymidine incorporation into DNA. Western blotting showed a marked down-regulation of cyclin G2 at the protein level in both cell lines. Overexpression of cyclin G2 in the two cell lines diminished the mitogenic effect of all three ligands. The use of specific inhibitors indicated that both the MAPK (mitogen-activated protein kinase) and the PI3K (phosphoinositide 3-kinase) pathways mediate the down-regulation of Ccng2. The down-regulation of CCNG2 by the three ligands was also observed in other cell lines: MCF-7, HMEC, Saos-2, R(-)/IR and INS-1. These results indicate that regulation of cyclin G2 is a key mechanism whereby insulin, insulin analogues and IGF-I stimulate cell proliferation.
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Hvid H, Blouin MJ, Birman E, Damgaard J, Poulsen F, Fels JJ, Fledelius C, Hansen BF, Pollak M. Treatment with insulin analog X10 and IGF-1 increases growth of colon cancer allografts. PLoS One 2013; 8:e79710. [PMID: 24260289 PMCID: PMC3832545 DOI: 10.1371/journal.pone.0079710] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Accepted: 09/24/2013] [Indexed: 12/28/2022] Open
Abstract
Obesity and type 2 diabetes are associated with an increased risk for development of certain forms of cancer, including colon cancer. The publication of highly controversial epidemiological studies in 2009 raised the possibility that use of the insulin analog glargine increases this risk further. However, it is not clear how mitogenic effects of insulin and insulin analogs measured in vitro correlate with tumor growth-promoting effects in vivo. The aim of this study was to examine possible growth-promoting effects of native human insulin, insulin X10 and IGF-1, which are considered positive controls in vitro, in a short-term animal model of an obesity- and diabetes-relevant cancer. We characterized insulin and IGF-1 receptor expression and the response to treatment with insulin, X10 and IGF-1 in the murine colon cancer cell line (MC38 cells) in vitro and in vivo. Furthermore, we examined pharmacokinetics and pharmacodynamics and monitored growth of MC38 cell allografts in mice with diet-induced obesity treated with human insulin, X10 and IGF-1. Treatment with X10 and IGF-1 significantly increased growth of MC38 cell allografts in mice with diet-induced obesity and we can therefore conclude that supra-pharmacological doses of the insulin analog X10, which is super-mitogenic in vitro and increased the incidence of mammary tumors in female rats in a 12-month toxicity study, also increase growth of tumor allografts in a short-term animal model.
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Affiliation(s)
- Henning Hvid
- Diabetes Research Unit, Novo Nordisk A/S, Maaloev, Denmark
- * E-mail:
| | - Marie-José Blouin
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
| | - Elena Birman
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
| | | | - Fritz Poulsen
- Diabetes Research Unit, Novo Nordisk A/S, Maaloev, Denmark
| | | | | | | | - Michael Pollak
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
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Gallagher EJ, Alikhani N, Tobin-Hess A, Blank J, Buffin NJ, Zelenko Z, Tennagels N, Werner U, LeRoith D. Insulin receptor phosphorylation by endogenous insulin or the insulin analog AspB10 promotes mammary tumor growth independent of the IGF-I receptor. Diabetes 2013; 62:3553-60. [PMID: 23835331 PMCID: PMC3781483 DOI: 10.2337/db13-0249] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Endogenous hyperinsulinemia and insulin receptor (IR)/IGF-I receptor (IGF-IR) phosphorylation in tumors are associated with a worse prognosis in women with breast cancer. In vitro, insulin stimulation of the IR increases proliferation of breast cancer cells. However, in vivo studies demonstrating that IR activation increases tumor growth, independently of IGF-IR activation, are lacking. We hypothesized that endogenous hyperinsulinemia increases mammary tumor growth by directly activating the IR rather than the IGF-IR or hybrid receptors. We aimed to determine whether stimulating the IR with the insulin analog AspB10 could increase tumor growth independently of IGF-IR signaling. We induced orthotopic mammary tumors in control FVB/n and hyperinsulinemic MKR mice, and treated them with the insulin analog AspB10, recombinant human IGF-I, or vehicle. Tumors from mice with endogenous hyperinsulinemia were larger and had greater IR phosphorylation, but not IGF-IR phosphorylation, than those from control mice. Chronic AspB10 administration also increased tumor growth and IR (but not IGF-IR) phosphorylation in tumors. IGF-I led to activation of both the IGF-IR and IR and probably hybrid receptors. Our results demonstrate that IR phosphorylation increases tumor growth, independently of IGF-IR/hybrid receptor phosphorylation, and warrant consideration when developing therapeutics targeting the IGF-IR, but not the IR.
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Affiliation(s)
- Emily Jane Gallagher
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Nyosha Alikhani
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Aviva Tobin-Hess
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jeffrey Blank
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Nicholas J. Buffin
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Zara Zelenko
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Norbert Tennagels
- R&D Diabetes Division, Sanofi-Aventis Deutschland, Frankfurt am Main, Germany
| | - Ulrich Werner
- R&D Diabetes Division, Sanofi-Aventis Deutschland, Frankfurt am Main, Germany
| | - Derek LeRoith
- Division of Endocrinology, Diabetes and Bone Diseases, Samuel Bronfman Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
- Corresponding author: Derek LeRoith,
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Abstract
OBJECTIVE The aim of this review article is to discuss the epidemiological links between diabetes and cancer; the potential biological mechanisms linking diabetes, obesity and cancer; the risk of cancer associated with antidiabetic medications. METHODS The data discussed in this review were obtained from the American Association of Clinical Endocrinologists Consensus Conference on Diabetes and Cancer, held in New York, NY, USA, September 2012. RESULTS The results of these studies demonstrate a significant association between diabetes and the risk of multiple cancers, including hepatocellular, pancreatic, endometrial, colorectal, breast, kidney, bladder, gastric, and ovarian cancer, non-Hodgkin lymphoma, T cell lymphoma and leukemia. There are multiple potential biological mechanisms that may link type 2 diabetes, obesity and cancer. Insulin resistance and hyperinsulinemia may lead to direct activation of the insulin receptors on tumor cells and promote tumor growth. Other potential mechanisms include increased circulating, local or bioavailable insulin-like growth factor 1, hyperglycemia, dyslipidemia, increased circulating or local estrogen, adipokines and direct and indirect effects of inflammatory cytokines. Epidemiological studies have had conflicting results regarding the associations between various classes of antidiabetic medication and cancer development. Animal studies have demonstrated increased tumor growth with certain medications, but their relevance to humans is uncertain. Metformin may, however, have protective effects on cancer development and may improve survival in patients with cancer. CONCLUSION We describe the current understanding of the links among diabetes, antidiabetic medication and cancer risk. We highlight some of the issues that should be addressed in the future to prevent cancer development and death in those with diabetes.
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Affiliation(s)
- Emily J Gallagher
- Department of Medicine, Division of Endocrinology, Mt Sinai School of Medicine, New York, New York 10029-6574, USA
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37
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Tennagels N, Welte S, Hofmann M, Brenk P, Schmidt R, Werner U. Differences in metabolic and mitogenic signallingof insulin glargine and AspB10 human insulin in rats [corrected]. Diabetologia 2013; 56:1826-34. [PMID: 23653049 PMCID: PMC3699703 DOI: 10.1007/s00125-013-2923-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 04/05/2013] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS In vitro, insulin glargine (A21Gly,B31Arg,B32Arg human insulin) has an insulin receptor (IR) profile similar to that of human insulin, but a slightly higher affinity for the IGF-1 receptor (IGF1R). AspB10 human insulin (AspB10), [corrected] the only insulin analogue with proven carcinogenic activity, has a greater affinity for IGF1R and IR, and a prolonged IR occupancy time. The pharmacological and signalling profile of therapeutic and suprapharmacological doses of glargine were analysed in different tissues of rats, and compared with human insulin and AspB10. METHODS Male Wistar rats were injected s.c. with human insulin or insulin analogue at doses of 1 to 200 U/kg, and the effects on blood glucose and the phosphorylation status of IR, IGF1R, Akt and extracellular signal-regulated protein kinase 1/2 in muscle, fat, liver and heart samples were investigated. RESULTS Glargine, AspB10 and human insulin lowered blood glucose, with the onset of action delayed with glargine. Glargine treatment resulted in phosphorylation levels of IR and Akt that were comparable with those achieved with human insulin, although delayed in time in some tissues. AspB10 treatment resulted in at least twofold higher phosphorylation levels and significantly longer duration of IR and Akt phosphorylation in most tissues. None of the insulin treatments resulted in detectable IGF1R phosphorylation in muscle or heart tissue, whereas intravenous injection of IGF-1 increased IGF1R phosphorylation. CONCLUSIONS/INTERPRETATION The IR signalling pattern of AspB10 in vivo is distinctly different from that of human insulin and insulin glargine, and might challenge the notion that activation of IGF1R plays a role in the observed carcinogenic effect of AspB10.
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Affiliation(s)
- N Tennagels
- Sanofi-Aventis Deutschland GmbH, Frankfurt am Main, Germany.
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38
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Gunter JH, Sarkar PL, Lubik AA, Nelson CC. New players for advanced prostate cancer and the rationalisation of insulin-sensitising medication. Int J Cell Biol. 2013;2013:834684. [PMID: 23573093 PMCID: PMC3614121 DOI: 10.1155/2013/834684] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 01/29/2013] [Indexed: 12/13/2022] Open
Abstract
Obesity and type 2 diabetes are recognised risk factors for the development of some cancers and, increasingly, predict more aggressive disease, treatment failure, and cancer-specific mortality. Many factors may contribute to this clinical observation. Hyperinsulinaemia, dyslipidaemia, hypoxia, ER stress, and inflammation associated with expanded adipose tissue are thought to be among the main culprits driving malignant growth and cancer advancement. This observation has led to the proposal of the potential utility of "old players" for the treatment of type 2 diabetes and metabolic syndrome as new cancer adjuvant therapeutics. Androgen-regulated pathways drive proliferation, differentiation, and survival of benign and malignant prostate tissue. Androgen deprivation therapy (ADT) exploits this dependence to systemically treat advanced prostate cancer resulting in anticancer response and improvement of cancer symptoms. However, the initial therapeutic response from ADT eventually progresses to castrate resistant prostate cancer (CRPC) which is currently incurable. ADT rapidly induces hyperinsulinaemia which is associated with more rapid treatment failure. We discuss current observations of cancer in the context of obesity, diabetes, and insulin-lowering medication. We provide an update on current treatments for advanced prostate cancer and discuss whether metabolic dysfunction, developed during ADT, provides a unique therapeutic window for rapid translation of insulin-sensitising medication as combination therapy with antiandrogen targeting agents for the management of advanced prostate cancer.
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Bolli GB, Hahn AD, Schmidt R, Eisenblaetter T, Dahmen R, Heise T, Becker RHA. Plasma exposure to insulin glargine and its metabolites M1 and M2 after subcutaneous injection of therapeutic and supratherapeutic doses of glargine in subjects with type 1 diabetes. Diabetes Care 2012; 35:2626-30. [PMID: 23093664 PMCID: PMC3507590 DOI: 10.2337/dc12-0270] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 07/10/2012] [Indexed: 02/03/2023]
Abstract
OBJECTIVE In vivo, after subcutaneous injection, insulin glargine (21(A)-Gly-31(B)-Arg-32(B)-Arg-human insulin) is enzymatically processed into 21(A)-Gly-human insulin (metabolite 1 [M1]). 21(A)-Gly-des-30(B)-Thr-human insulin (metabolite 2 [M2]) is also found. In vitro, glargine exhibits slightly higher affinity, whereas M1 and M2 exhibit lower affinity for IGF-1 receptor, as well as mitogenic properties, versus human insulin. The aim of the study was to quantitate plasma concentrations of glargine, M1, and M2 after subcutaneous injection of glargine in male type 1 diabetic subjects. RESEARCH DESIGN AND METHODS Glargine, M1, and M2 were determined in blood samples obtained from 12, 11, and 11 type 1 diabetic subjects who received single subcutaneous doses of 0.3, 0.6, or 1.2 units · kg(-1) glargine in a euglycemic clamp study. Glargine, M1, and M2 were extracted using immunoaffinity columns and quantified by a specific liquid chromatography-tandem mass spectrometry assay. Lower limit of quantification was 0.2 ng · mL(-1) (33 pmol · L(-1)) per analyte. RESULTS Plasma M1 concentration increased with increasing dose; geometric mean (percent coefficient of variation) M1-area under the curve between time of dosing and 30 h after dosing (AUC(0-30h)) was 1,261 (66), 2,867 (35), and 4,693 (22) pmol · h · L(-1) at doses of 0.3, 0.6, and 1.2 units · kg(-1), respectively, and correlated with metabolic effect assessed as pharmacodynamics-AUC(0-30h) of the glucose infusion rate following glargine administration (r = 0.74; P < 0.01). Glargine and M2 were detectable in only one-third of subjects and at a few time points. CONCLUSIONS After subcutaneous injection of glargine in male subjects with type 1 diabetes, exposure to glargine is marginal, if any, even at supratherapeutic doses. Glargine is rapidly and nearly completely processed to M1 (21(A)-Gly-human insulin), which mediates the metabolic effect of injected glargine.
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Affiliation(s)
- Geremia B Bolli
- Department of Internal Medicine, University of Perugia, Perugia, Italy.
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40
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Abstract
Despite the availability of many other agents, insulin is widely used as a treatment for type 2 diabetes. In vitro, insulin stimulates the growth of cancer cells, through the interaction with insulin-like growth factor-1 (IGF-1) receptors and its own receptors. In observational surveys on type 2 diabetes, insulin therapy is associated with an increased incidence of several forms of cancer, although it is difficult to discriminate the effect of confounders from that of insulin itself. Randomized trials do not confirm the increased risk associated with insulin therapy, although they do not allow to rule out some negative effects on specific forms of cancer, at least at higher doses. Among insulin analogues, glargine has a higher affinity for the IGF-1 receptor and a greater mitogenic potency in vitro than human insulin, but it is extensively metabolized in vitro to products with low IGF-1 receptor affinity. Overall, epidemiological studies suggest a possible increase of risk with glargine, with respect to human insulin, only at high doses and for some forms of cancer (i.e., breast). Data from clinical trials do not confirm, but are still insufficient to totally exclude, such increased risk. However, beneficial effects of insulin outweigh potential cancer risks.
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Affiliation(s)
- Edoardo Mannucci
- Agenzia Diabetologia, Ponte Nuovo, Ospedale di Careggi, Via delle Oblate, 4-50141 Firenze, Italy
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41
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Abstract
Insulin analogues have been developed in an attempt to achieve a more physiological replacement of insulin and thereby a better glycaemic control. However, structural modification of the insulin molecule may result in altered binding affinities and activities to the IGF1 receptor (IGF1R). As a consequence, insulin analogues may theoretically have an increased mitogenic action compared to human insulin. In view of the lifelong exposure and large patient populations involved, insulin analogues with an increased mitogenic effect in comparison to human insulin may potentially constitute a major health problem, since these analogues may possibly induce the growth of pre-existing neoplasms. This hypothesis has been evaluated extensively in vitro and also in vivo by using animal models. In vitro, all at present commercially available insulin analogues have lower affinities for the insulin receptor (IR). Although it has been suggested that especially insulin analogues with an increased affinity for the IGF1R (such as insulin glargine) are more mitogenic when tested in vitro in cells expressing a high proportion of IGF1R, the question remains whether this has any clinical consequences. At present, there are several uncertainties which make it very difficult to answer this question decisively. In addition, recent data suggest that insulin (or insulin analogues)-mediated stimulation of IRs may play a key role in the progression of human cancer. More detailed information is required to elucidate the exact mechanisms as to how insulin analogues may activate the IR and IGF1R and how this activation may be linked to mitogenesis.
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Affiliation(s)
- Aimee J Varewijck
- Division of Endocrinology, Department of Internal Medicine, Erasmus Medical Center, CE Rotterdam, The Netherlands
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42
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Hansen BF, Glendorf T, Hegelund AC, Lundby A, Lützen A, Slaaby R, Stidsen CE. Molecular characterisation of long-acting insulin analogues in comparison with human insulin, IGF-1 and insulin X10. PLoS One 2012; 7:e34274. [PMID: 22590494 PMCID: PMC3348127 DOI: 10.1371/journal.pone.0034274] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 02/26/2012] [Indexed: 12/29/2022] Open
Abstract
AIMS/HYPOTHESIS There is controversy with respect to molecular characteristics of insulin analogues. We report a series of experiments forming a comprehensive characterisation of the long acting insulin analogues, glargine and detemir, in comparison with human insulin, IGF-1, and the super-mitogenic insulin, X10. METHODS We measured binding of ligands to membrane-bound and solubilised receptors, receptor activation and mitogenicity in a number of cell types. RESULTS Detemir and glargine each displayed a balanced affinity for insulin receptor (IR) isoforms A and B. This was also true for X10, whereas IGF-1 had a higher affinity for IR-A than IR-B. X10 and glargine both exhibited a higher relative IGF-1R than IR binding affinity, whereas detemir displayed an IGF-1R:IR binding ratio of ≤ 1. Ligands with high relative IGF-1R affinity also had high affinity for IR/IGF-1R hybrid receptors. In general, the relative binding affinities of the analogues were reflected in their ability to phosphorylate the IR and IGF-1R. Detailed analysis revealed that X10, in contrast to the other ligands, seemed to evoke a preferential phosphorylation of juxtamembrane and kinase domain phosphorylation sites of the IR. Sustained phosphorylation was only observed from the IR after stimulation with X10, and after stimulation with IGF-1 from the IGF-1R. Both X10 and glargine showed an increased mitogenic potency compared to human insulin in cells expressing many IGF-1Rs, whereas only X10 showed increased mitogenicity in cells expressing many IRs. CONCLUSIONS Detailed analysis of receptor binding, activation and in vitro mitogenicity indicated no molecular safety concern with detemir.
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Affiliation(s)
- Bo F Hansen
- Diabetes Research Unit, Novo Nordisk A/S, Måløv, Denmark.
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43
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Glendorf T, Knudsen L, Stidsen CE, Hansen BF, Hegelund AC, Sørensen AR, Nishimura E, Kjeldsen T. Systematic evaluation of the metabolic to mitogenic potency ratio for B10-substituted insulin analogues. PLoS One 2012; 7:e29198. [PMID: 22383948 PMCID: PMC3285154 DOI: 10.1371/journal.pone.0029198] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 11/22/2011] [Indexed: 12/14/2022] Open
Abstract
Background Insulin analogues comprising acidic amino acid substitutions at position B10 have previously been shown to display increased mitogenic potencies compared to human insulin and the underlying molecular mechanisms have been subject to much scrutiny and debate. However, B10 is still an attractive position for amino acid substitutions given its important role in hexamer formation. The aim of this study was to investigate the relationships between the receptor binding properties as well as the metabolic and mitogenic potencies of a series of insulin analogues with different amino acid substitutions at position B10 and to identify a B10-substituted insulin analogue without an increased mitogenic to metabolic potency ratio. Methodology/Principal Findings A panel of ten singly-substituted B10 insulin analogues with different amino acid side chain characteristics were prepared and insulin receptor (both isoforms) and IGF-I receptor binding affinities using purified receptors, insulin receptor dissociation rates using BHK cells over-expressing the human insulin receptor, metabolic potencies by lipogenesis in isolated rat adipocytes, and mitogenic potencies using two different cell types predominantly expressing either the insulin or the IGF-I receptor were systematically investigated. Only analogues B10D and B10E with significantly increased insulin and IGF-I receptor affinities as well as decreased insulin receptor dissociation rates displayed enhanced mitogenic potencies in both cell types employed. For the remaining analogues with less pronounced changes in receptor affinities and insulin receptor dissociation rates, no apparent correlation between insulin receptor occupancy time and mitogenicity was observed. Conclusions/Significance Several B10-substituted insulin analogues devoid of disproportionate increases in mitogenic compared to metabolic potencies were identified. In the present study, receptor binding affinity rather than insulin receptor off-rate appears to be the major determinant of both metabolic and mitogenic potency. Our results also suggest that the increased mitogenic potency is attributable to both insulin and IGF-I receptor activation.
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Affiliation(s)
- Tine Glendorf
- Diabetes Research Unit, Novo Nordisk A/S, Maaloev, Denmark.
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44
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Abstract
Although several early phase clinical trials raised enthusiasm for the use of insulin-like growth factor I receptor (IGF1R)-specific antibodies for cancer treatment, initial Phase III results in unselected patients have been disappointing. Further clinical studies may benefit from the use of predictive biomarkers to identify probable responders, the use of rational combination therapies and the consideration of alternative targeting strategies, such as ligand-specific antibodies and receptor-specific tyrosine kinase inhibitors. Targeting insulin and IGF signalling also needs to be considered in the broader context of the pathophysiology that relates obesity and diabetes to neoplasia, and the effects of anti-diabetic drugs, including metformin, on cancer risk and prognosis. The insulin and IGFI receptor family is also relevant to the development of PI3K-AKT pathway inhibitors.
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Affiliation(s)
- Michael Pollak
- Lady Davis Research Institute and McGill University, Montreal, Quebec H3T1E2, Canada.
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45
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Morcavallo A, Genua M, Palummo A, Kletvikova E, Jiracek J, Brzozowski AM, Iozzo RV, Belfiore A, Morrione A. Insulin and insulin-like growth factor II differentially regulate endocytic sorting and stability of insulin receptor isoform A. J Biol Chem 2012; 287:11422-36. [PMID: 22318726 DOI: 10.1074/jbc.m111.252478] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The insulin receptor isoform A (IR-A) binds both insulin and insulin-like growth factor (IGF)-II, although the affinity for IGF-II is 3-10-fold lower than insulin depending on a cell and tissue context. Notably, in mouse embryonic fibroblasts lacking the IGF-IR and expressing solely the IR-A (R-/IR-A), IGF-II is a more potent mitogen than insulin. As receptor endocytosis and degradation provide spatial and temporal regulation of signaling events, we hypothesized that insulin and IGF-II could affect IR-A biological responses by differentially regulating IR-A trafficking. Using R-/IR-A cells, we discovered that insulin evoked significant IR-A internalization, a process modestly affected by IGF-II. However, the differential internalization was not due to IR-A ubiquitination. Notably, prolonged stimulation of R-/IR-A cells with insulin, but not with IGF-II, targeted the receptor to a degradative pathway. Similarly, the docking protein insulin receptor substrate 1 (IRS-1) was down-regulated after prolonged insulin but not IGF-II exposure. Similar results were also obtained in experiments using [NMeTyr(B26)]-insulin, an insulin analog with IR-A binding affinity similar to IGF-II. Finally, we discovered that IR-A was internalized through clathrin-dependent and -independent pathways, which differentially regulated the activation of downstream effectors. Collectively, our results suggest that a lower affinity of IGF-II for the IR-A promotes lower IR-A phosphorylation and activation of early downstream effectors vis à vis insulin but may protect IR-A and IRS-1 from down-regulation thereby evoking sustained and robust mitogenic stimuli.
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Affiliation(s)
- Alaide Morcavallo
- Department of Urology and Endocrine Mechanisms and Hormone Action Program, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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46
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Kulahin N, Sanni SJ, Slaaby R, Nøhr J, Gammeltoft S, Hansen JL, Jorgensen R. A BRET assay for monitoring insulin receptor interactions and ligand pharmacology. J Recept Signal Transduct Res 2012; 32:57-64. [PMID: 22272819 DOI: 10.3109/10799893.2011.647351] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The insulin receptor (IR) belongs to the receptor tyrosine kinase super family and plays an important role in glucose homeostasis. The receptor interacts with several large docking proteins that mediate signaling from the receptor, including the insulin receptor substrate (IRS) family and Src homology-2-containing proteins (Src). Here, we applied the bioluminescence resonance energy transfer 2 (BRET2) technique to study the IR signaling pathways. The interaction between the IR and the substrates IRS1, IRS4 and Shc was examined in response to ligands with different signaling properties. The association between IR and the interacting partners could successfully be monitored when co-expressing green fluorescent protein 2 (GFP2) tagged substrates with Renilla reniformis luciferase 8 (Rluc8) tagged IR. Through additional optimization steps, we developed a stable and flexible BRET2 assay for monitoring the interactions between the IR and its substrates. Furthermore, the insulin analogue X10 was characterized in the BRET2 assay and was found to be 10 times more potent with respect to IRS1, IRS4 and Shc recruitment compared to human insulin. This study demonstrates that the BRET2 technique can be applied to study IR signaling pathways, and that this assay can be used as a platform for screening and characterization of IR ligands.
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Affiliation(s)
- Nikolaj Kulahin
- Incretin Biology, Hagedorn Research Institute, Gentofte, Denmark
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47
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Abstract
New therapeutic approaches to counter the increasing prevalence of obesity and type 2 diabetes mellitus are in high demand. Deregulation of the phosphoinositide-3-kinase (PI3K)/v-akt murine thymoma viral oncogene homologue (AKT), mitogen-activated protein kinase (MAPK) and AMP-activated protein kinase (AMPK) pathways, which are essential for glucose homeostasis, often results in obesity and diabetes. Thus, these pathways should be attractive therapeutic targets. However, with the exception of metformin, which is considered to function mainly by activating AMPK, no treatment for the metabolic syndrome based on targeting protein kinases has yet been developed. By contrast, therapies based on the inhibition of the PI3K/AKT and MAPK pathways are already successful in the treatment of diverse cancer types and inflammatory diseases. This contradiction prompted us to review the signal transduction mechanisms of PI3K/AKT, MAPK and AMPK and their roles in glucose homeostasis, and we also discuss current clinical implications.
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48
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Abstract
We have exploited a prandial insulin analog to elucidate the underlying structure and dynamics of insulin as a monomer in solution. A model was provided by insulin lispro (the active component of Humalog(®); Eli Lilly and Co.). Whereas NMR-based modeling recapitulated structural relationships of insulin crystals (T-state protomers), dynamic anomalies were revealed by amide-proton exchange kinetics in D(2)O. Surprisingly, the majority of hydrogen bonds observed in crystal structures are only transiently maintained in solution, including key T-state-specific inter-chain contacts. Long-lived hydrogen bonds (as defined by global exchange kinetics) exist only at a subset of four α-helical sites (two per chain) flanking an internal disulfide bridge (cystine A20-B19); these sites map within the proposed folding nucleus of proinsulin. The anomalous flexibility of insulin otherwise spans its active surface and may facilitate receptor binding. Because conformational fluctuations promote the degradation of pharmaceutical formulations, we envisage that "dynamic re-engineering" of insulin may enable design of ultra-stable formulations for humanitarian use in the developing world.
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Affiliation(s)
- Qing-Xin Hua
- Department of Biochemistry, School of Medicine, Case Western Reserve UniversityCleveland, OH, USA
| | - Wenhua Jia
- Department of Biochemistry, School of Medicine, Case Western Reserve UniversityCleveland, OH, USA
| | - Michael A. Weiss
- Department of Biochemistry, School of Medicine, Case Western Reserve UniversityCleveland, OH, USA
- *Correspondence: Michael A. Weiss, Department of Biochemistry, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue – Wood W436, Cleveland, OH 44106-4935, USA. e-mail:
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