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Determinants of IGF-II influencing stability, receptor binding and activation. Sci Rep 2022; 12:4695. [PMID: 35304516 PMCID: PMC8933565 DOI: 10.1038/s41598-022-08467-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/28/2022] [Indexed: 11/28/2022] Open
Abstract
Insulin like growth factor II (IGF-II) is involved in metabolic and mitogenic signalling in mammalian cells and plays important roles in normal fetal development and postnatal growth. It is structurally similar to insulin and binds not only with high affinity to the type 1 insulin-like growth factor receptor (IGF-1R) but also to the insulin receptor isoform A (IR-A). As IGF-II expression is commonly upregulated in cancer and its signalling promotes cancer cell survival, an antagonist that blocks IGF-II action without perturbing insulin signalling would be invaluable. The high degree of structural homology between the IR and IGF-1R makes selectively targeting either receptor in the treatment of IGF-II-dependent cancers very challenging. However, there are sequence differences between insulin and IGF-II that convey receptor selectivity and influence binding affinity and signalling outcome. Insulin residue YB16 is a key residue involved in maintaining insulin stability, dimer formation and IR binding. Mutation of this residue to glutamine (as found in IGF-II) results in reduced binding affinity. In this study we sought to determine if the equivalent residue Q18 in IGF-II plays a similar role. We show through site-directed mutagenesis of Q18 that this residue contributes to IGF-II structural integrity, selectivity of IGF-1R/IR binding, but surprisingly does not influence IR-A signalling activation. These findings provide insights into a unique IGF-II residue that can influence receptor binding specificity whilst having little influence on signalling outcome.
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2
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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] [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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3
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Ong SC, Belgi A, van Lierop B, Delaine C, Andrikopoulos S, MacRaild CA, Norton RS, Haworth NL, Robinson AJ, Forbes BE. Probing the correlation between insulin activity and structural stability through introduction of the rigid A6-A11 bond. J Biol Chem 2018; 293:11928-11943. [PMID: 29899115 DOI: 10.1074/jbc.ra118.002486] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 06/10/2018] [Indexed: 11/06/2022] Open
Abstract
The development of fast-acting and highly stable insulin analogues is challenging. Insulin undergoes structural transitions essential for binding and activation of the insulin receptor (IR), but these conformational changes can also affect insulin stability. Previously, we substituted the insulin A6-A11 cystine with a rigid, non-reducible C=C linkage ("dicarba" linkage). A cis-alkene permitted the conformational flexibility of the A-chain N-terminal helix necessary for high-affinity IR binding, resulting in surprisingly rapid activity in vivo Here, we show that, unlike the rapidly acting LysB28ProB29 insulin analogue (KP insulin), cis-dicarba insulin is not inherently monomeric. We also show that cis-dicarba KP insulin lowers blood glucose levels even more rapidly than KP insulin, suggesting that an inability to oligomerize is not responsible for the observed rapid activity onset of cis-dicarba analogues. Although rapid-acting, neither dicarba species is stable, as assessed by fibrillation and thermodynamics assays. MALDI analyses and molecular dynamics simulations of cis-dicarba insulin revealed a previously unidentified role of the A6-A11 linkage in insulin conformational dynamics. By controlling the conformational flexibility of the insulin B-chain helix, this linkage affects overall insulin structural stability. This effect is independent of its regulation of the A-chain N-terminal helix flexibility necessary for IR engagement. We conclude that high-affinity IR binding, rapid in vivo activity, and insulin stability can be regulated by the specific conformational arrangement of the A6-A11 linkage. This detailed understanding of insulin's structural dynamics may aid in the future design of rapid-acting insulin analogues with improved stability.
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Affiliation(s)
- Shee Chee Ong
- From the College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
| | - Alessia Belgi
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Bianca van Lierop
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Carlie Delaine
- From the College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
| | - Sofianos Andrikopoulos
- the Department of Medicine, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Christopher A MacRaild
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Raymond S Norton
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Naomi L Haworth
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia.,the Research School of Chemistry, Australian National University, Acton, Australian Capital Territory 2601, Australia, and.,the School of Life and Environmental Sciences, Deakin University, Waurn Ponds, Victoria 3216, Australia
| | - Andrea J Robinson
- the School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Briony E Forbes
- From the College of Medicine and Public Health, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia,
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Belfiore A, Malaguarnera R, Vella V, Lawrence MC, Sciacca L, Frasca F, Morrione A, Vigneri R. Insulin Receptor Isoforms in Physiology and Disease: An Updated View. Endocr Rev 2017; 38:379-431. [PMID: 28973479 PMCID: PMC5629070 DOI: 10.1210/er.2017-00073] [Citation(s) in RCA: 234] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/13/2017] [Indexed: 02/08/2023]
Abstract
The insulin receptor (IR) gene undergoes differential splicing that generates two IR isoforms, IR-A and IR-B. The physiological roles of IR isoforms are incompletely understood and appear to be determined by their different binding affinities for insulin-like growth factors (IGFs), particularly for IGF-2. Predominant roles of IR-A in prenatal growth and development and of IR-B in metabolic regulation are well established. However, emerging evidence indicates that the differential expression of IR isoforms may also help explain the diversification of insulin and IGF signaling and actions in various organs and tissues by involving not only different ligand-binding affinities but also different membrane partitioning and trafficking and possibly different abilities to interact with a variety of molecular partners. Of note, dysregulation of the IR-A/IR-B ratio is associated with insulin resistance, aging, and increased proliferative activity of normal and neoplastic tissues and appears to sustain detrimental effects. This review discusses novel information that has generated remarkable progress in our understanding of the physiology of IR isoforms and their role in disease. We also focus on novel IR ligands and modulators that should now be considered as an important strategy for better and safer treatment of diabetes and cancer and possibly other IR-related diseases.
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Affiliation(s)
- Antonino Belfiore
- Endocrinology, Department of Health Sciences, University Magna Graecia of Catanzaro, 88100 Catanzaro, Italy
| | - Roberta Malaguarnera
- Endocrinology, Department of Health Sciences, University Magna Graecia of Catanzaro, 88100 Catanzaro, Italy
| | - Veronica Vella
- School of Human and Social Sciences, University Kore of Enna, via della Cooperazione, 94100 Enna, Italy
| | - Michael C. Lawrence
- Structural Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Laura Sciacca
- Endocrinology, Department of Clinical and Experimental Medicine, University of Catania, Garibaldi-Nesima Hospital, 95122 Catania, Italy
| | - Francesco Frasca
- Endocrinology, Department of Clinical and Experimental Medicine, University of Catania, Garibaldi-Nesima Hospital, 95122 Catania, Italy
| | - Andrea Morrione
- Department of Urology and Biology of Prostate Cancer Program, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Riccardo Vigneri
- Endocrinology, Department of Clinical and Experimental Medicine, University of Catania, Garibaldi-Nesima Hospital, 95122 Catania, Italy
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Halicka D, Zhao H, Li J, Garcia J, Podhorecka M, Darzynkiewicz Z. DNA Damage Response Resulting from Replication Stress Induced by Synchronization of Cells by Inhibitors of DNA Replication: Analysis by Flow Cytometry. Methods Mol Biol 2017; 1524:107-119. [PMID: 27815899 DOI: 10.1007/978-1-4939-6603-5_7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cell synchronization is often achieved by transient inhibition of DNA replication. When cultured in the presence of such inhibitors as hydroxyurea, aphidicolin or excess of thymidine the cells that become arrested at the entrance to S-phase upon release from the block initiate progression through S then G2 and M. However, exposure to these inhibitors at concentrations commonly used to synchronize cells leads to activation of ATR and ATM protein kinases as well as phosphorylation of Ser139 of histone H2AX. This observation of DNA damage signaling implies that synchronization of cells by these inhibitors is inducing replication stress. Thus, a caution should be exercised while interpreting data obtained with use of cells synchronized this way since they do not represent unperturbed cell populations in a natural metabolic state. This chapter critically outlines virtues and vices of most cell synchronization methods. It also presents the protocol describing an assessment of phosphorylation of Ser139 on H2AX and activation of ATM in cells treated with aphidicolin, as a demonstrative of one of several DNA replication inhibitors that are being used for cell synchronization. Phosphorylation of Ser139H2AX and Ser1981ATM in individual cells is detected immunocytochemically with phospho-specific Abs and intensity of immunofluorescence is measured by flow cytometry. Concurrent measurement of cellular DNA content followed by multiparameter analysis allows one to correlate the extent of phosphorylation of these proteins in response to aphidicolin with the cell cycle phase.
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Affiliation(s)
- Dorota Halicka
- Department of Pathology, Brander Cancer Research Institute, New York Medical College, 40 Sunshine Cottage Road, Valhalla, NY, 10595, USA
| | - Hong Zhao
- Department of Pathology, Brander Cancer Research Institute, New York Medical College, 40 Sunshine Cottage Road, Valhalla, NY, 10595, USA
| | - Jiangwei Li
- Department of Pathology, Brander Cancer Research Institute, New York Medical College, 40 Sunshine Cottage Road, Valhalla, NY, 10595, USA
| | - Jorge Garcia
- Department of Pathology, Brander Cancer Research Institute, New York Medical College, 40 Sunshine Cottage Road, Valhalla, NY, 10595, USA
| | - Monika Podhorecka
- Department of Hemato-Oncology and Bone Marrow Transplantation, Medical University, Lublin, Poland
| | - Zbigniew Darzynkiewicz
- Department of Pathology, Brander Cancer Research Institute, New York Medical College, 40 Sunshine Cottage Road, Valhalla, NY, 10595, USA.
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Flannery CA, Saleh FL, Choe GH, Selen DJ, Kodaman PH, Kliman HJ, Wood TL, Taylor HS. Differential Expression of IR-A, IR-B and IGF-1R in Endometrial Physiology and Distinct Signature in Adenocarcinoma. J Clin Endocrinol Metab 2016; 101:2883-91. [PMID: 27088794 PMCID: PMC4929835 DOI: 10.1210/jc.2016-1795] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 04/13/2016] [Indexed: 01/07/2023]
Abstract
CONTEXT Type 2 diabetes and obesity are risk factors for endometrial hyperplasia and cancer, suggesting that hyperinsulinemia contributes to pathogenesis. Insulin action through insulin receptor (IR) splice variants IR-A and IR-B regulates cellular mitogenesis and metabolism, respectively. OBJECTIVE We hypothesized that IR-A and IR-B are differentially regulated in normal endometrium, according to mitogenic and metabolic requirements through the menstrual cycle, as well as in endometrial hyperplasia and cancer. DESIGN IR-A, IR-B, and IGF-1 receptor (IGF-1R) mRNA was quantified in endometrium, endometrial epithelial and stromal cells, and in vitro after hormone stimulation. SETTING Academic center. PATIENTS Endometrium was collected from women with regular cycles (n = 71), complex hyperplasia (n = 5), or endometrioid adenocarcinoma (n = 11). INTERVENTION(S) In vitro sex-steroid treatment. MAIN OUTCOME MEASURE(S) IR-A and IR-B expression Results: IR-A increased dramatically during the early proliferative phase, 20-fold more than IR-B. In early secretory phase, IR-B and IGF-1R expression increased, reaching maximal expression, whereas IR-A decreased. In adenocarcinoma, IR-B and IGF-1R expression was 5- to 6-fold higher than normal endometrium, whereas IR-A expression was similar to IR-B. Receptor expression was unrelated to body mass index. CONCLUSION IR-A was elevated during the normal proliferative phase, and in endometrial hyperplasia and adenocarcinoma. The dramatic early rise of IR-A in normal endometrium indicates IR-A is the predominant isoform responsible for initial estrogen-independent endometrial proliferation as well as that of cancer. IR-B is elevated during the normal secretory phase when glucose uptake and glycogen synthesis support embryo development. Differing from other cancers, IR-B expression equals mitogenic IR-A in endometrial adenocarcinoma. Differential IR isoform expression suggests a distinct role for each in endometrial physiology and cancer.
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MESH Headings
- Adenocarcinoma/genetics
- Adenocarcinoma/metabolism
- Adenocarcinoma/pathology
- Adult
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Carcinoma, Endometrioid/genetics
- Carcinoma, Endometrioid/metabolism
- Carcinoma, Endometrioid/pathology
- Cells, Cultured
- Endometrial Hyperplasia/genetics
- Endometrial Hyperplasia/metabolism
- Endometrial Hyperplasia/pathology
- Endometrial Neoplasms/genetics
- Endometrial Neoplasms/metabolism
- Endometrial Neoplasms/pathology
- Endometrium/metabolism
- Endometrium/physiology
- Female
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic
- Humans
- Menstrual Cycle/genetics
- Menstrual Cycle/metabolism
- Middle Aged
- Protein Subunits/genetics
- Protein Subunits/metabolism
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Receptor, Insulin/genetics
- Receptor, Insulin/metabolism
- Transcriptome
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Affiliation(s)
- Clare A Flannery
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Farrah L Saleh
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Gina H Choe
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Daryl J Selen
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Pinar H Kodaman
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Harvey J Kliman
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Teresa L Wood
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
| | - Hugh S Taylor
- Obstetrics, Gynecology, and Reproductive Sciences (C.A.F., F.L.S., G.H.C., D.J.S., P.H.K., H.J.K., H.S.T.), Yale School of Medicine, New Haven, Connecticut 06520; Internal Medicine (C.A.F.), Yale School of Medicine, New Haven, Connecticut 06520; and Pharmacology, Physiology and Neuroscience and Cancer Center (T.L.W.), NJ Medical School, Rutgers University, Newark, New Jersey 07101
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7
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Westermeier F, Sáez T, Arroyo P, Toledo F, Gutiérrez J, Sanhueza C, Pardo F, Leiva A, Sobrevia L. Insulin receptor isoforms: an integrated view focused on gestational diabetes mellitus. Diabetes Metab Res Rev 2016; 32:350-65. [PMID: 26431063 DOI: 10.1002/dmrr.2729] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/14/2015] [Accepted: 09/27/2015] [Indexed: 12/17/2022]
Abstract
The human insulin receptor (IR) exists in two isoforms that differ by the absence (IR-A) or the presence (IR-B) of a 12-amino acid segment encoded by exon 11. Both isoforms are functionally distinct regarding their binding affinities and intracellular signalling. However, the underlying mechanisms related to their cellular functions in several tissues are only partially understood. In this review, we summarize the current knowledge in this field regarding the alternative splicing of IR isoform, tissue-specific distribution and signalling both in physiology and disease, with an emphasis on the human placenta in gestational diabetes mellitus (GDM). Furthermore, we discuss the clinical relevance of IR isoforms highlighted by findings that show altered insulin signalling due to differential IR-A and IR-B expression in human placental endothelium in GDM pregnancies. Future research and clinical studies focused on the role of IR isoform signalling might provide novel therapeutic targets for treating GDM to improve the adverse maternal and neonatal outcomes.
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Affiliation(s)
- F Westermeier
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- Advanced Centre for Chronic Diseases (ACCDiS), Faculty of Chemical & Pharmaceutical Sciences and Faculty of Medicine, Universidad de Chile, Santiago, Chile
- Faculty of Science, Universidad San Sebastián, Santiago, Chile
| | - T Sáez
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- University Medical Centre Groningen (UMCG), Faculty of Medicine, University of Groningen, Groningen, The Netherlands
| | - P Arroyo
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - F Toledo
- Department of Basic Sciences, Faculty of Sciences, Universidad del Bío-Bío, Chillán, Chile
| | - J Gutiérrez
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- Cellular Signalling and Differentiation Laboratory (CSDL), School of Medical Technology, Health Sciences Faculty, Universidad San Sebastian, Santiago, Chile
| | - C Sanhueza
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - F Pardo
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - A Leiva
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - L Sobrevia
- Cellular and Molecular Physiology Laboratory (CMPL), Division of Obstetrics and Gynaecology, School of Medicine, Faculty of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
- Department of Physiology, Faculty of Pharmacy, Universidad de Sevilla, Seville, Spain
- University of Queensland Centre for Clinical Research (UQCCR), Faculty of Medicine and Biomedical Sciences, University of Queensland, Queensland, Australia
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8
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Wei W, Zhang WY, Bai JB, Zhang HX, Zhao YY, Li XY, Zhao SH. The NF-ҡB modulated miR-195/497 inhibit myoblast proliferation by targeting Igf1r/Insr and cyclin genes. J Cell Sci 2015; 129:39-50. [DOI: 10.1242/jcs.174235] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 11/09/2015] [Indexed: 12/26/2022] Open
Abstract
MicroRNAs (miRNAs) play important roles in the development of skeletal muscle. In our previous study, expression of miR-195 and miR-497 were shown to be up-regulated during muscle development in pigs. In this study, we investigated the roles of these two miRNAs in myogenesis and analyzed their transcriptional regulation. Our results showed that miR-195 and miR-497 were up-regulated during muscle development and myoblast differentiation. Moreover, miR-195/497 inhibited proliferation but not differentiation in C2C12 cells. Further investigation revealed that Igf1r, Insr, Ccnd2, and Ccne1 were directly targeted by miR-195/497 in myoblasts. In addition, we confirmed that similarly expressed miR-195 and miR-497 were negatively regulated by nuclear factor-kappaB (NF-ҡB) in both myoblasts and skeletal muscle tissue. Our data illustrated that the NF-ҡB-miR-195/497-Igf1r/Insr-Ccnd2/Ccne1 signaling pathway played important roles in the myogenesis. Our study provides novel evidence for the roles of miR-195/497 in muscle development.
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Affiliation(s)
- Wei Wei
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
- College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Wei-Ya Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jian-Bo Bai
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Hai-Xin Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Yuan-Yuan Zhao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Xin-Yun Li
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
| | - Shu-Hong Zhao
- Key Laboratory of Animal Genetics, Breeding and Reproduction of Ministry of Education, Huazhong Agricultural University, Wuhan 430070, PR China
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9
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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] [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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10
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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] [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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11
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Li L, Pan S, Zhou X, Meng X, Han X, Ren Y, Yang K, Guan Y. Reduction of in-stent restenosis risk on nickel-free stainless steel by regulating cell apoptosis and cell cycle. PLoS One 2013; 8:e62193. [PMID: 23638002 PMCID: PMC3637440 DOI: 10.1371/journal.pone.0062193] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 03/14/2013] [Indexed: 01/29/2023] Open
Abstract
High nitrogen nickel-free austenitic stainless steel (HNNF SS) is one of the biomaterials developed recently for circumventing the in-stent restenosis (ISR) in coronary stent applications. To understand the ISR-resistance mechanism, we have conducted a comparative study of cellular and molecular responses of human umbilical vein endothelial cells (HUVECs) to HNNF SS and 316L SS (nickel-containing austenitic 316L stainless steel) which is the stent material used currently. CCK-8 analysis and flow cytometric analysis were used to assess the cellular responses (proliferation, apoptosis, and cell cycle), and quantitative real-time PCR (qRT-PCR) was used to analyze the gene expression profile of HUVECs exposed to HNNF SS and 316L SS, respectively. Flow cytometry analysis revealed that 316L SS could activate the cellular apoptosis more efficiently and initiate an earlier entry into the S-phase of cell cycle than HNNF SS. At the molecular level, qRT-PCR results showed that the genes regulating cell apoptosis and autophagy were overexpressed on 316L SS. Further examination indicated that nickel released from 316L SS triggered the cell apoptosis via Fas-Caspase8-Caspase3 exogenous pathway. These molecular mechanisms of HUVECs present a good model for elucidating the observed cellular responses. The findings in this study furnish valuable information for understanding the mechanism of ISR-resistance on the cellular and molecular basis as well as for developing new biomedical materials for stent applications.
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Affiliation(s)
- Liming Li
- Key Laboratory of Medical Cell Biology, Ministry of Education, Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
- Institute of Biotechnology, College of Sciences, Northeastern University, Shenyang, China
| | - Shuang Pan
- Key Laboratory of Medical Cell Biology, Ministry of Education, Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Xiaohang Zhou
- Key Laboratory of Medical Cell Biology, Ministry of Education, Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Xin Meng
- Key Laboratory of Medical Cell Biology, Ministry of Education, Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Xiaoxi Han
- Key Laboratory of Medical Cell Biology, Ministry of Education, Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Yibin Ren
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
| | - Ke Yang
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang, China
| | - Yifu Guan
- Key Laboratory of Medical Cell Biology, Ministry of Education, Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
- * E-mail:
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12
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Knudsen L, Hansen BF, Jensen P, Pedersen TÅ, Vestergaard K, Schäffer L, Blagoev B, Oleksiewicz MB, Kiselyov VV, De Meyts P. Agonism and antagonism at the insulin receptor. PLoS One 2012; 7:e51972. [PMID: 23300584 PMCID: PMC3531387 DOI: 10.1371/journal.pone.0051972] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 11/14/2012] [Indexed: 11/29/2022] Open
Abstract
Insulin can trigger metabolic as well as mitogenic effects, the latter being pharmaceutically undesirable. An understanding of the structure/function relationships between insulin receptor (IR) binding and mitogenic/metabolic signalling would greatly facilitate the preclinical development of new insulin analogues. The occurrence of ligand agonism and antagonism is well described for G protein-coupled receptors (GPCRs) and other receptors but in general, with the exception of antibodies, not for receptor tyrosine kinases (RTKs). In the case of the IR, no natural ligand or insulin analogue has been shown to exhibit antagonistic properties, with the exception of a crosslinked insulin dimer (B29-B’29). However, synthetic monomeric or dimeric peptides targeting sites 1 or 2 of the IR were shown to be either agonists or antagonists. We found here that the S961 peptide, previously described to be an IR antagonist, exhibited partial agonistic effects in the 1–10 nM range, showing altogether a bell-shaped dose-response curve. Intriguingly, the agonistic effects of S961 were seen only on mitogenic endpoints (3H-thymidine incorporation), and not on metabolic endpoints (14C-glucose incorporation in adipocytes and muscle cells). The agonistic effects of S961 were observed in 3 independent cell lines, with complete concordance between mitogenicity (3H-thymidine incorporation) and phosphorylation of the IR and Akt. Together with the B29-B’29 crosslinked dimer, S961 is a rare example of a mixed agonist/antagonist for the human IR. A plausible mechanistic explanation based on the bivalent crosslinking model of IR activation is proposed.
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Affiliation(s)
- Louise Knudsen
- Receptor Systems Biology Laboratory, Hagedorn Research Institute, Gentofte, Denmark.
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13
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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] [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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14
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Kang B, Austin LA, El-Sayed MA. Real-time molecular imaging throughout the entire cell cycle by targeted plasmonic-enhanced Rayleigh/Raman spectroscopy. NANO LETTERS 2012; 12:5369-5375. [PMID: 22978570 DOI: 10.1021/nl3027586] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Due to their strong enhancement of scattered light, plasmonic nanoparticles have been utilized for various biological and medical applications. Here, we describe a new technique, Targeted Plasmonic-Enhanced Single-Cell Rayleigh/Raman Spectroscopy, to monitor the molecular changes of any cell-component, such as the nucleus, during the different phases of its full cell cycle by simultaneously recording its Rayleigh images and Raman vibration spectra in real-time. The analysis of the observed Raman DNA and protein peaks allowed the different phases of the cell cycle to be identified. This technique could be used for disease diagnostics and potentially improve our understanding of the molecular mechanisms of cellular functions such as division, death, signaling, and drug action.
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Affiliation(s)
- Bin Kang
- Laser Dynamics Laboratory, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-040, USA
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15
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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] [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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Hansen BF, Kurtzhals P, Jensen AB, Dejgaard A, Russell-Jones D. Insulin X10 revisited: a super-mitogenic insulin analogue. Diabetologia 2011; 54:2226-31. [PMID: 21633908 DOI: 10.1007/s00125-011-2203-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Accepted: 04/06/2011] [Indexed: 12/13/2022]
Abstract
The molecular safety of insulin analogues has received a great deal of attention over the last year. In particular, attention has been directed to the mitogenic properties of insulin analogues as compared with human insulin. Understanding the mechanisms implicated in mediating mitogenic effects of insulin is therefore of particular interest. In this review we detail the story of the rapid-acting insulin analogue known as X10, which was the first insulin analogue in clinical development, but ended up being discontinued at an early clinical development stage following findings of mammary tumours in female Sprague-Dawley rats. The molecular characteristics of insulin X10, along with its interaction at both the IGF-1 receptor and the insulin receptor, have provided us with important insights into mechanisms implicated in metabolic and mitogenic signalling of insulin analogues.
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van Duyvenvoorde HA, van Doorn J, Koenig J, Gauguin L, Oostdijk W, Wade JD, Karperien M, Ruivenkamp CAL, Losekoot M, van Setten PA, Walenkamp MJE, Noordam C, De Meyts P, Wit JM. The severe short stature in two siblings with a heterozygous IGF1 mutation is not caused by a dominant negative effect of the putative truncated protein. Growth Horm IGF Res 2011; 21:44-50. [PMID: 21237682 DOI: 10.1016/j.ghir.2010.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 12/14/2010] [Accepted: 12/16/2010] [Indexed: 11/24/2022]
Abstract
OBJECTIVE While in previous studies heterozygosity for an Insulin-Like Growth Factor 1 (IGF1) defect only modestly decreased height and head circumference, we recently reported on two siblings with severe short stature with a maternally transmitted heterozygous duplication of 4 nucleotides, resulting in a frame shift and a premature termination codon in the IGF1 gene. In this paper we describe the structural and functional characteristics of the putative truncated IGF-I protein. DESIGN Two children, their mother and maternal grandfather carried the mutation. In addition, two family members who were not affected were included in the study. Mutant (MT) IGF-I was synthesized in oxidized and reduced form using two methods. Neutral gel filtration studies were carried out with wild-type (WT) and synthetic MT IGF-I. Binding analysis of synthetic MT IGF-I to the IGF1R and insulin receptors were performed with EBNA-293 cells, stably transfected with the IGF-I receptor, and IM9 cells. L6 cells were used to examine the mitogenic potency and the potential antagonizing effect of synthetic MT IGF-I by [(3)H]-thymidine incorporation assays. RESULTS In the sera of both the carriers and non-carriers the proportion of (125)I-IGF-I that was associated with the 150 kDa complex was somewhat less (varying between ~37 and ~52%) than in normal pooled serum (~53-~63%) and, instead, slightly increased amounts of radioactivity were eluted in the 40-50 kDa fraction (consisting of binary IGF-IGFBP complexes) or remained unbound. Synthetic MT IGF-I did not bind to the IGF-I receptor, nor antagonize the growth-promoting effect of IGF-I. It did bind to IGFBPs, but was barely incorporated into 150 kDa complexes. Because in all cases WT IGF-I immunoreactivity was recovered in one peak, corresponding to the MW of WT IGF-I, i.e. ~7.6 kDa, an interaction of circulating truncated mutant peptide with WT IGF-I is very unlikely. CONCLUSIONS There is no evidence that the severe short stature associated with heterozygosity for this novel IGF1 mutation in children born from a mother with the same mutation is caused by a dominant negative effect of the truncated protein. We speculate that the growth failure is caused by a combination of partial IGF-I deficiency, placental IGF-I insufficiency, and other genetic factors.
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Affiliation(s)
- H A van Duyvenvoorde
- Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands.
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Sajid W, Kulahin N, Schluckebier G, Ribel U, Henderson HR, Tatar M, Hansen BF, Svendsen AM, Kiselyov VV, Nørgaard P, Wahlund PO, Brandt J, Kohanski RA, Andersen AS, De Meyts P. Structural and biological properties of the Drosophila insulin-like peptide 5 show evolutionary conservation. J Biol Chem 2010; 286:661-73. [PMID: 20974844 DOI: 10.1074/jbc.m110.156018] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the crystal structure of two variants of Drosophila melanogaster insulin-like peptide 5 (DILP5) at a resolution of 1.85 Å. DILP5 shares the basic fold of the insulin peptide family (T conformation) but with a disordered B-chain C terminus. DILP5 dimerizes in the crystal and in solution. The dimer interface is not similar to that observed in vertebrates, i.e. through an anti-parallel β-sheet involving the B-chain C termini but, in contrast, is formed through an anti-parallel β-sheet involving the B-chain N termini. DILP5 binds to and activates the human insulin receptor and lowers blood glucose in rats. It also lowers trehalose levels in Drosophila. Reciprocally, human insulin binds to the Drosophila insulin receptor and induces negative cooperativity as in the human receptor. DILP5 also binds to insect insulin-binding proteins. These results show high evolutionary conservation of the insulin receptor binding properties despite divergent insulin dimerization mechanisms.
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Affiliation(s)
- Waseem Sajid
- Receptor Systems Biology Laboratory, Insulin and Incretin Biology, Hagedorn Research Institute, 2820 Gentofte, Denmark
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Hvid H, Klopfleisch R, Vienberg S, Hansen BF, Thorup I, Jensen HE, Oleksiewicz MB. Unique expression pattern of the three insulin receptor family members in the rat mammary gland: dominance of IGF-1R and IRR over the IR, and cyclical IGF-1R expression. J Appl Toxicol 2010; 31:312-28. [DOI: 10.1002/jat.1627] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Henning Hvid
- Department of Veterinary Disease Biology; Faculty of Life Sciences; University of Copenhagen; Denmark
- Pathology; Novo Nordisk A/S; Copenhagen Denmark
| | | | - Sara Vienberg
- Insulin Biology; Novo Nordisk A/S; Copenhagen Denmark
| | - Bo F. Hansen
- Insulin Biology; Novo Nordisk A/S; Copenhagen Denmark
| | | | - Henrik E. Jensen
- Department of Veterinary Disease Biology; Faculty of Life Sciences; University of Copenhagen; Denmark
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