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Davis JC, Ryaboshapkina M, Kenty JH, Eser PÖ, Menon S, Tyrberg B, Melton DA. IAPP Marks Mono-hormonal Stem-cell Derived β Cells that Maintain Stable Insulin Production in vitro and in vivo. bioRxiv 2024:2024.04.10.587726. [PMID: 38645166 PMCID: PMC11030367 DOI: 10.1101/2024.04.10.587726] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Islet transplantation for treatment of diabetes is limited by availability of donor islets and requirements for immunosuppression. Stem cell-derived islets might circumvent these issues. SC-islets effectively control glucose metabolism post transplantation, but do not yet achieve full function in vitro with current published differentiation protocols. We aimed to identify markers of mature subpopulations of SC-β cells by studying transcriptional changes associated with in vivo maturation of SC-β cells using RNA-seq and co-expression network analysis. The β cell-specific hormone islet amyloid polypeptide (IAPP) emerged as the top candidate to be such a marker. IAPP+ cells had more mature β cell gene expression and higher cellular insulin content than IAPP- cells in vitro. IAPP+ INS+ cells were more stable in long-term culture than IAPP- INS+ cells and retained insulin expression after transplantation into mice. Finally, we conducted a small molecule screen to identify compounds that enhance IAPP expression. Aconitine up-regulated IAPP and could help to optimize differentiation protocols.
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Affiliation(s)
- Jeffrey C. Davis
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Boston MA 02138, United States of America
| | - Maria Ryaboshapkina
- Translational Science and Experimental Medicine, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Jennifer H. Kenty
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Boston MA 02138, United States of America
| | | | - Suraj Menon
- RDI Operations, Granta Park, AstraZeneca, Cambridge CB21 6GP, UK
| | - Björn Tyrberg
- Global Insights, Analytics & Commercial Excellence, BioPharmaceuticals Business Unit, AstraZeneca, Gothenburg, Sweden
| | - Douglas A. Melton
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Boston MA 02138, United States of America
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2
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Grunddal KV, Trammell SAJ, Bæch-Laursen C, Andersen DB, Xu SFS, Andersen H, Gillum MP, Ghiasi SM, Novak I, Tyrberg B, Li C, Rosenkilde MM, Hartmann B, Holst JJ, Kuhre RE. Opposing roles of the entero-pancreatic hormone urocortin-3 in glucose metabolism in rats. Diabetologia 2022; 65:1018-1031. [PMID: 35325259 PMCID: PMC9076751 DOI: 10.1007/s00125-022-05675-9] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 12/20/2021] [Indexed: 11/03/2022]
Abstract
AIM/HYPOTHESIS Urocortin-3 (UCN3) is a glucoregulatory peptide produced in the gut and pancreatic islets. The aim of this study was to clarify the acute effects of UCN3 on glucose regulation following an oral glucose challenge and to investigate the mechanisms involved. METHODS We studied the effect of UCN3 on blood glucose, gastric emptying, glucose absorption and secretion of gut and pancreatic hormones in male rats. To supplement these physiological studies, we mapped the expression of UCN3 and the UCN3-sensitive receptor, type 2 corticotropin-releasing factor receptor (CRHR2), by means of fluorescence in situ hybridisation and by gene expression analysis. RESULTS In rats, s.c. administration of UCN3 strongly inhibited gastric emptying and glucose absorption after oral administration of glucose. Direct inhibition of gastrointestinal motility may be responsible because UCN3's cognate receptor, CRHR2, was detected in gastric submucosal plexus and in interstitial cells of Cajal. Despite inhibited glucose absorption, post-challenge blood glucose levels matched those of rats given vehicle in the low-dose UCN3 group, because UCN3 concomitantly inhibited insulin secretion. Higher UCN3 doses did not further inhibit gastric emptying, but the insulin inhibition progressed resulting in elevated post-challenge glucose and lipolysis. Incretin hormones and somatostatin (SST) secretion from isolated perfused rat small intestine was unaffected by UCN3 infusion; however, UCN3 infusion stimulated secretion of somatostatin from delta cells in the isolated perfused rat pancreas which, unlike alpha cells and beta cells, expressed Crhr2. Conversely, acute antagonism of CRHR2 signalling increased insulin secretion by reducing SST signalling. Consistent with these observations, acute drug-induced inhibition of CRHR2 signalling improved glucose tolerance in rats to a similar degree as administration of glucagon-like peptide-1. UCN3 also powerfully inhibited glucagon secretion from isolated perfused rat pancreas (perfused with 3.5 mmol/l glucose) in a SST-dependent manner, suggesting that UCN3 may be involved in glucose-induced inhibition of glucagon secretion. CONCLUSIONS/INTERPRETATION Our combined data indicate that UCN3 is an important glucoregulatory hormone that acts through regulation of gastrointestinal and pancreatic functions.
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Affiliation(s)
- Kaare V Grunddal
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Samuel A J Trammell
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Cecilie Bæch-Laursen
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Stella F S Xu
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Helle Andersen
- Global Obesity and Liver Disease Research, Novo Nordisk, Måløv, Denmark
| | - Matthew P Gillum
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Seyed M Ghiasi
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Section of Cell Biology and Functional Genomics, Division of Diabetes, Endocrinology and Metabolism, Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College, London, UK
| | - Ivana Novak
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Björn Tyrberg
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Chien Li
- Global Obesity and Liver Disease Research, Novo Nordisk, Seattle, WA, USA
| | - Mette M Rosenkilde
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bolette Hartmann
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark.
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical, Sciences, University of Copenhagen, Copenhagen, Denmark.
- Global Obesity and Liver Disease Research, Novo Nordisk, Måløv, Denmark.
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Karlsson D, Ahnmark A, Sabirsh A, Andréasson AC, Gennemark P, Sandinge AS, Chen L, Tyrberg B, Lindén D, Sörhede Winzell M. Inhibition of SGLT2 Preserves Function and Promotes Proliferation of Human Islets Cells In Vivo in Diabetic Mice. Biomedicines 2022; 10:biomedicines10020203. [PMID: 35203411 PMCID: PMC8868601 DOI: 10.3390/biomedicines10020203] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 01/08/2022] [Accepted: 01/12/2022] [Indexed: 01/27/2023] Open
Abstract
Dapagliflozin is a sodium-glucose co-transporter 2 (SGLT2) inhibitor used for the treatment of diabetes. This study examines the effects of dapagliflozin on human islets, focusing on alpha and beta cell composition in relation to function in vivo, following treatment of xeno-transplanted diabetic mice. Mouse beta cells were ablated by alloxan, and dapagliflozin was provided in the drinking water while controls received tap water. Body weight, food and water intake, plasma glucose, and human C-peptide levels were monitored, and intravenous arginine/glucose tolerance tests (IVarg GTT) were performed to evaluate islet function. The grafted human islets were isolated at termination and stained for insulin, glucagon, Ki67, caspase 3, and PDX-1 immunoreactivity in dual and triple combinations. In addition, human islets were treated in vitro with dapagliflozin at different glucose concentrations, followed by insulin and glucagon secretion measurements. SGLT2 inhibition increased the animal survival rate and reduced plasma glucose, accompanied by sustained human C-peptide levels and improved islet response to glucose/arginine. SGLT2 inhibition increased both alpha and beta cell proliferation (Ki67+glucagon+ and Ki67+insulin+) while apoptosis was reduced (caspase3+glucagon+ and caspase3+insulin+). Alpha cells were fewer following inhibition of SGLT2 with increased glucagon/PDX-1 double-positive cells, a marker of alpha to beta cell transdifferentiation. In vitro treatment of human islets with dapagliflozin had no apparent impact on islet function. In summary, SGLT2 inhibition supported human islet function in vivo in the hyperglycemic milieu and potentially promoted alpha to beta cell transdifferentiation, most likely through an indirect mechanism.
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Affiliation(s)
- Daniel Karlsson
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (D.K.); (A.A.); (A.-C.A.); (L.C.); (D.L.)
| | - Andrea Ahnmark
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (D.K.); (A.A.); (A.-C.A.); (L.C.); (D.L.)
| | - Alan Sabirsh
- Advanced Drug Delivery, Pharmaceutical Sciences R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden;
| | - Anne-Christine Andréasson
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (D.K.); (A.A.); (A.-C.A.); (L.C.); (D.L.)
| | - Peter Gennemark
- Drug Metabolism and Pharmacokinetics, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), Biopharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (P.G.); (A.-S.S.)
- Department of Biomedical Engineering, Linköping University, 58183 Linköping, Sweden
| | - Ann-Sofie Sandinge
- Drug Metabolism and Pharmacokinetics, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), Biopharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (P.G.); (A.-S.S.)
| | - Lihua Chen
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (D.K.); (A.A.); (A.-C.A.); (L.C.); (D.L.)
| | - Björn Tyrberg
- Translational Science and Experimental Medicine, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), Biopharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden;
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
| | - Daniel Lindén
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (D.K.); (A.A.); (A.-C.A.); (L.C.); (D.L.)
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, 41390 Gothenburg, Sweden
| | - Maria Sörhede Winzell
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Mölndal, 43150 Gothenburg, Sweden; (D.K.); (A.A.); (A.-C.A.); (L.C.); (D.L.)
- Correspondence:
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Serrano J, Meshram NN, Soundarapandian MM, Smith KR, Mason C, Brown IS, Tyrberg B, Kyriazis GA. Saccharin Stimulates Insulin Secretion Dependent on Sweet Taste Receptor-Induced Activation of PLC Signaling Axis. Biomedicines 2022; 10:biomedicines10010120. [PMID: 35052799 PMCID: PMC8773316 DOI: 10.3390/biomedicines10010120] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/27/2021] [Accepted: 01/04/2022] [Indexed: 02/05/2023] Open
Abstract
Background: Saccharin is a common artificial sweetener and a bona fide ligand for sweet taste receptors (STR). STR can regulate insulin secretion in beta cells, so we investigated whether saccharin can stimulate insulin secretion dependent on STR and the activation of phospholipase C (PLC) signaling. Methods: We performed in vivo and in vitro approaches in mice and cells with loss-of-function of STR signaling and specifically assessed the involvement of a PLC signaling cascade using real-time biosensors and calcium imaging. Results: We found that the ingestion of a physiological amount of saccharin can potentiate insulin secretion dependent on STR. Similar to natural sweeteners, saccharin triggers the activation of the PLC signaling cascade, leading to calcium influx and the vesicular exocytosis of insulin. The effects of saccharin also partially require transient receptor potential cation channel M5 (TRPM5) activity. Conclusions: Saccharin ingestion may transiently potentiate insulin secretion through the activation of the canonical STR signaling pathway. These physiological effects provide a framework for understanding the potential health impact of saccharin use and the contribution of STR in peripheral tissues.
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Affiliation(s)
- Joan Serrano
- Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA; (J.S.); (N.N.M.); (C.M.); (I.S.B.)
| | - Nishita N. Meshram
- Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA; (J.S.); (N.N.M.); (C.M.); (I.S.B.)
| | | | - Kathleen R. Smith
- Sanford Burnham Prebys Medical Discovery Institute, Lake Nona, FL 32827, USA; (M.M.S.); (K.R.S.)
| | - Carter Mason
- Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA; (J.S.); (N.N.M.); (C.M.); (I.S.B.)
| | - Ian S. Brown
- Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA; (J.S.); (N.N.M.); (C.M.); (I.S.B.)
| | - Björn Tyrberg
- Department of Physiology, Sahlgrenska Academy, University of Gothenburg, 405 30 Gothenburg, Sweden;
| | - George A. Kyriazis
- Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, OH 43210, USA; (J.S.); (N.N.M.); (C.M.); (I.S.B.)
- Correspondence: or
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5
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Zhou AX, Mondal T, Tabish AM, Abadpour S, Ericson E, Smith DM, Knöll R, Scholz H, Kanduri C, Tyrberg B, Althage M. The long noncoding RNA TUNAR modulates Wnt signaling and regulates human β-cell proliferation. Am J Physiol Endocrinol Metab 2021; 320:E846-E857. [PMID: 33682459 DOI: 10.1152/ajpendo.00335.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [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] [Indexed: 12/12/2022]
Abstract
Many long noncoding RNAs (lncRNAs) are enriched in pancreatic islets and several lncRNAs are linked to type 2 diabetes (T2D). Although they have emerged as potential players in β-cell biology and T2D, little is known about their functions and mechanisms in human β-cells. We identified an islet-enriched lncRNA, TUNAR (TCL1 upstream neural differentiation-associated RNA), which was upregulated in β-cells of patients with T2D and promoted human β-cell proliferation via fine-tuning of the Wnt pathway. TUNAR was upregulated following Wnt agonism by a glycogen synthase kinase-3 (GSK3) inhibitor in human β-cells. Reciprocally, TUNAR repressed a Wnt antagonist Dickkopf-related protein 3 (DKK3) and stimulated Wnt pathway signaling. DKK3 was aberrantly expressed in β-cells of patients with T2D and displayed a synchronized regulatory pattern with TUNAR at the single cell level. Mechanistically, DKK3 expression was suppressed by the repressive histone modifier enhancer of zeste homolog 2 (EZH2). TUNAR interacted with EZH2 in β-cells and facilitated EZH2-mediated suppression of DKK3. These findings reveal a novel cell-specific epigenetic mechanism via islet-enriched lncRNA that fine-tunes the Wnt pathway and subsequently human β-cell proliferation.NEW & NOTEWORTHY The discovery that long noncoding RNA TUNAR regulates β-cell proliferation may be important in designing new treatments for diabetes.
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Affiliation(s)
- Alex-Xianghua Zhou
- Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Tanmoy Mondal
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital Laboratory Medicine, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Ali Mustafa Tabish
- Integrated Cardio Metabolic Centre, Karolinska Institute, Stockholm, Sweden
| | - Shadab Abadpour
- Department of Transplant Medicine, Institute for Surgical Research, Oslo University Hospital, Oslo, Norway
- Hybrid Technology Hub, Centre of Excellence, University of Oslo, Oslo, Norway
| | - Elke Ericson
- Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - David M Smith
- Emerging Innovations Unit, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, United Kingdom
| | - Ralph Knöll
- Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
- Integrated Cardio Metabolic Centre, Karolinska Institute, Stockholm, Sweden
| | - Hanne Scholz
- Department of Transplant Medicine, Institute for Surgical Research, Oslo University Hospital, Oslo, Norway
| | - Chandrasekhar Kanduri
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Björn Tyrberg
- Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Magnus Althage
- Research and Early Development Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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6
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Abadpour S, Tyrberg B, Schive SW, Huldt CW, Gennemark P, Ryberg E, Rydén-Bergsten T, Smith DM, Korsgren O, Skrtic S, Scholz H, Winzell MS. Inhibition of the prostaglandin D 2-GPR44/DP2 axis improves human islet survival and function. Diabetologia 2020; 63:1355-1367. [PMID: 32350565 PMCID: PMC7286861 DOI: 10.1007/s00125-020-05138-z] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 02/28/2020] [Indexed: 12/12/2022]
Abstract
AIMS/HYPOTHESIS Inflammatory signals and increased prostaglandin synthesis play a role during the development of diabetes. The prostaglandin D2 (PGD2) receptor, GPR44/DP2, is highly expressed in human islets and activation of the pathway results in impaired insulin secretion. The role of GPR44 activation on islet function and survival rate during chronic hyperglycaemic conditions is not known. In this study, we investigate GPR44 inhibition by using a selective GPR44 antagonist (AZ8154) in human islets both in vitro and in vivo in diabetic mice transplanted with human islets. METHODS Human islets were exposed to PGD2 or proinflammatory cytokines in vitro to investigate the effect of GPR44 inhibition on islet survival rate. In addition, the molecular mechanisms of GPR44 inhibition were investigated in human islets exposed to high concentrations of glucose (HG) and to IL-1β. For the in vivo part of the study, human islets were transplanted under the kidney capsule of immunodeficient diabetic mice and treated with 6, 60 or 100 mg/kg per day of a GPR44 antagonist starting from the transplantation day until day 4 (short-term study) or day 17 (long-term study) post transplantation. IVGTT was performed on mice at day 10 and day 15 post transplantation. After termination of the study, metabolic variables, circulating human proinflammatory cytokines, and hepatocyte growth factor (HGF) were analysed in the grafted human islets. RESULTS PGD2 or proinflammatory cytokines induced apoptosis in human islets whereas GPR44 inhibition reversed this effect. GPR44 inhibition antagonised the reduction in glucose-stimulated insulin secretion induced by HG and IL-1β in human islets. This was accompanied by activation of the Akt-glycogen synthase kinase 3β signalling pathway together with phosphorylation and inactivation of forkhead box O-1and upregulation of pancreatic and duodenal homeobox-1 and HGF. Administration of the GPR44 antagonist for up to 17 days to diabetic mice transplanted with a marginal number of human islets resulted in reduced fasting blood glucose and lower glucose excursions during IVGTT. Improved glucose regulation was supported by increased human C-peptide levels compared with the vehicle group at day 4 and throughout the treatment period. GPR44 inhibition reduced plasma levels of TNF-α and growth-regulated oncogene-α/chemokine (C-X-C motif) ligand 1 and increased the levels of HGF in human islets. CONCLUSIONS/INTERPRETATION Inhibition of GPR44 in human islets has the potential to improve islet function and survival rate under inflammatory and hyperglycaemic stress. This may have implications for better survival rate of islets following transplantation.
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Affiliation(s)
- Shadab Abadpour
- Department of Transplant Medicine and Institute for Surgical Research, Oslo University Hospital, Sognsvannsveien 20, 0027, Oslo, Norway
- Hybrid Technology Hub, Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Björn Tyrberg
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
| | - Simen W Schive
- Department of Transplant Medicine and Institute for Surgical Research, Oslo University Hospital, Sognsvannsveien 20, 0027, Oslo, Norway
| | - Charlotte Wennberg Huldt
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
| | - Peter Gennemark
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
- Department of Biomedical Engineering, University of Linköping, Linköping, Sweden
| | - Erik Ryberg
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
| | - Tina Rydén-Bergsten
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
| | - David M Smith
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
- Hit Discovery, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Olle Korsgren
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, University of Uppsala, Uppsala, Sweden
| | - Stanko Skrtic
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden
- Institute of Medicine at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Hanne Scholz
- Department of Transplant Medicine and Institute for Surgical Research, Oslo University Hospital, Sognsvannsveien 20, 0027, Oslo, Norway.
- Hybrid Technology Hub, Centre of Excellence, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
| | - Maria Sörhede Winzell
- Research and Early Development, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Peppredsleden 1, 431 83 Mölndal, Gothenburg, Sweden.
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7
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Khilji MS, Bresson SE, Verstappen D, Pihl C, Andersen PAK, Agergaard JB, Dahlby T, Bryde TH, Klindt K, Nielsen CK, Walentinsson A, Zivkovic D, Bousquet MP, Tyrberg B, Richardson SJ, Morgan NG, Mandrup-Poulsen T, Marzec MT. The inducible β5i proteasome subunit contributes to proinsulin degradation in GRP94-deficient β-cells and is overexpressed in type 2 diabetes pancreatic islets. Am J Physiol Endocrinol Metab 2020; 318:E892-E900. [PMID: 32255680 DOI: 10.1152/ajpendo.00372.2019] [Citation(s) in RCA: 6] [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] [Indexed: 12/26/2022]
Abstract
Proinsulin is a misfolding-prone protein, and its efficient breakdown is critical when β-cells are confronted with high-insulin biosynthetic demands, to prevent endoplasmic reticulum stress, a key trigger of secretory dysfunction and, if uncompensated, apoptosis. Proinsulin degradation is thought to be performed by the constitutively expressed standard proteasome, while the roles of other proteasomes are unknown. We recently demonstrated that deficiency of the proinsulin chaperone glucose-regulated protein 94 (GRP94) causes impaired proinsulin handling and defective insulin secretion associated with a compensated endoplasmic reticulum stress response. Taking advantage of this model of restricted folding capacity, we investigated the role of different proteasomes in proinsulin degradation, reasoning that insulin secretory dynamics require an inducible protein degradation system. We show that the expression of only one enzymatically active proteasome subunit, namely, the inducible β5i-subunit, was increased in GRP94 CRISPR/Cas9 knockout (KO) cells. Additionally, the level of β5i-containing intermediate proteasomes was significantly increased in these cells, as was β5i-related chymotrypsin-like activity. Moreover, proinsulin levels were restored in GRP94 KO upon β5i small interfering RNA-mediated knockdown. Finally, the fraction of β-cells expressing the β5i-subunit is increased in human islets from type 2 diabetes patients. We conclude that β5i is an inducible proteasome subunit dedicated to the degradation of mishandled proinsulin.
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Affiliation(s)
- Muhammad Saad Khilji
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sophie Emilie Bresson
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Danielle Verstappen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Radboud Universiteit, Nijmegen, The Netherlands
| | - Celina Pihl
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Phillip Alexander Keller Andersen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jette Bach Agergaard
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Dahlby
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tenna Holgersen Bryde
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristian Klindt
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christian Kronborg Nielsen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anna Walentinsson
- Translational Science and Experimental Medicine, Early Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Dusan Zivkovic
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Université de Toulouse, Toulouse, France
| | - Marie-Pierre Bousquet
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Université de Toulouse, Toulouse, France
| | - Björn Tyrberg
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Sarah J Richardson
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom
| | - Noel G Morgan
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Exeter, United Kingdom
| | - Thomas Mandrup-Poulsen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michal Tomasz Marzec
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism, and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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8
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Khilji MS, Verstappen D, Dahlby T, Burstein Prause MC, Pihl C, Bresson SE, Bryde TH, Keller Andersen PA, Klindt K, Zivkovic D, Bousquet-Dubouch MP, Tyrberg B, Mandrup-Poulsen T, Marzec MT. The intermediate proteasome is constitutively expressed in pancreatic beta cells and upregulated by stimulatory, low concentrations of interleukin 1 β. PLoS One 2020; 15:e0222432. [PMID: 32053590 PMCID: PMC7018053 DOI: 10.1371/journal.pone.0222432] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 01/21/2020] [Indexed: 12/11/2022] Open
Abstract
A central and still open question regarding the pathogenesis of autoimmune diseases, such as type 1 diabetes, concerns the processes that underlie the generation of MHC-presented autoantigenic epitopes that become targets of autoimmune attack. Proteasomal degradation is a key step in processing of proteins for MHC class I presentation. Different types of proteasomes can be expressed in cells dictating the repertoire of peptides presented by the MHC class I complex. Of particular interest for type 1 diabetes is the proteasomal configuration of pancreatic β cells, as this might facilitate autoantigen presentation by β cells and thereby their T-cell mediated destruction. Here we investigated whether so-called inducible subunits of the proteasome are constitutively expressed in β cells, regulated by inflammatory signals and participate in the formation of active intermediate or immuno-proteasomes. We show that inducible proteasomal subunits are constitutively expressed in human and rodent islets and an insulin-secreting cell-line. Moreover, the β5i subunit is incorporated into active intermediate proteasomes that are bound to 19S or 11S regulatory particles. Finally, inducible subunit expression along with increase in total proteasome activities are further upregulated by low concentrations of IL-1β stimulating proinsulin biosynthesis. These findings suggest that the β cell proteasomal repertoire is more diverse than assumed previously and may be highly responsive to a local inflammatory islet environment.
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Affiliation(s)
- Muhammad Saad Khilji
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Physiology, University of Veterinary and Animal Sciences, Lahore, Punjab, Pakistan
| | - Danielle Verstappen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Radboud Universiteit, Nijmegen, Netherlands
| | - Tina Dahlby
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Celina Pihl
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sophie Emilie Bresson
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tenna Holgersen Bryde
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Phillip Alexander Keller Andersen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristian Klindt
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Dusan Zivkovic
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Université de Toulouse, Toulouse, France
| | - Marie-Pierre Bousquet-Dubouch
- Institut de Pharmacologie et de Biologie Structurale, Centre National de la Recherche Scientifique, Université de Toulouse, Toulouse, France
| | - Björn Tyrberg
- Department of Physiology, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Thomas Mandrup-Poulsen
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Michal Tomasz Marzec
- Laboratory of Immuno-endocrinology, Inflammation, Metabolism and Oxidation Section, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- * E-mail:
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9
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Kuhre RE, Ghiasi SM, Adriaenssens AE, Wewer Albrechtsen NJ, Andersen DB, Aivazidis A, Chen L, Mandrup-Poulsen T, Ørskov C, Gribble FM, Reimann F, Wierup N, Tyrberg B, Holst JJ. No direct effect of SGLT2 activity on glucagon secretion. Diabetologia 2019; 62:1011-1023. [PMID: 30903205 PMCID: PMC7212061 DOI: 10.1007/s00125-019-4849-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [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: 11/17/2018] [Accepted: 02/12/2019] [Indexed: 02/03/2023]
Abstract
AIMS/HYPOTHESIS Sodium-glucose cotransporter (SGLT) 2 inhibitors constitute a new class of glucose-lowering drugs, but they increase glucagon secretion, which may counteract their glucose-lowering effect. Previous studies using static incubation of isolated human islets or the glucagon-secreting cell line α-TC1 suggested that this results from direct inhibition of alpha cell SGLT1/2-activity. The aim of this study was to test whether the effects of SGLT2 on glucagon secretion demonstrated in vitro could be reproduced in a more physiological setting. METHODS We explored the effect of SGLT2 activity on glucagon secretion using isolated perfused rat pancreas, a physiological model for glucagon secretion. Furthermore, we investigated Slc5a2 (the gene encoding SGLT2) expression in rat islets as well as in mouse and human islets and in mouse and human alpha, beta and delta cells to test for potential inter-species variations. SGLT2 protein content was also investigated in mouse, rat and human islets. RESULTS Glucagon output decreased three- to fivefold within minutes of shifting from low (3.5 mmol/l) to high (10 mmol/l) glucose (4.0 ± 0.5 pmol/15 min vs 1.3 ± 0.3 pmol/15 min, p < 0.05). The output was unaffected by inhibition of SGLT1/2 with dapagliflozin or phloridzin or by addition of the SGLT1/2 substrate α-methylglucopyranoside, whether at low or high glucose concentrations (p = 0.29-0.99). Insulin and somatostatin secretion (potential paracrine regulators) was also unaffected. Slc5a2 expression and SGLT2 protein were marginal or below detection limit in rat, mouse and human islets and in mouse and human alpha, beta and delta cells. CONCLUSIONS/INTERPRETATION Our combined data show that increased plasma glucagon during SGLT2 inhibitor treatment is unlikely to result from direct inhibition of SGLT2 in alpha cells, but instead may occur downstream of their blood glucose-lowering effects.
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Affiliation(s)
- Rune E Kuhre
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Seyed M Ghiasi
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Alice E Adriaenssens
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Nicolai J Wewer Albrechtsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark
| | - Daniel B Andersen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Alexander Aivazidis
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Lihua Chen
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Thomas Mandrup-Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
| | - Cathrine Ørskov
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark
| | - Fiona M Gribble
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Frank Reimann
- Metabolic Research Laboratories and Medical Research Council Metabolic Diseases Unit, Wellcome Trust-Medical Research Council, Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Nils Wierup
- Department of Experimental Medical Science, Faculty of Medicine, Lund University Diabetes Centre, Lund, Sweden
| | - Björn Tyrberg
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Jens J Holst
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Panum Institute, Blegdamsvej 3B, DK-2200, Copenhagen N, Denmark.
- Novo Nordisk Foundation Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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10
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Ghiasi SM, Dahlby T, Hede Andersen C, Haataja L, Petersen S, Omar-Hmeadi M, Yang M, Pihl C, Bresson SE, Khilji MS, Klindt K, Cheta O, Perone MJ, Tyrberg B, Prats C, Barg S, Tengholm A, Arvan P, Mandrup-Poulsen T, Marzec MT. Endoplasmic Reticulum Chaperone Glucose-Regulated Protein 94 Is Essential for Proinsulin Handling. Diabetes 2019; 68:747-760. [PMID: 30670477 PMCID: PMC6425875 DOI: 10.2337/db18-0671] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 12/26/2018] [Indexed: 12/18/2022]
Abstract
Although endoplasmic reticulum (ER) chaperone binding to mutant proinsulin has been reported, the role of protein chaperones in the handling of wild-type proinsulin is underinvestigated. Here, we have explored the importance of glucose-regulated protein 94 (GRP94), a prominent ER chaperone known to fold insulin-like growth factors, in proinsulin handling within β-cells. We found that GRP94 coimmunoprecipitated with proinsulin and that inhibition of GRP94 function and/or expression reduced glucose-dependent insulin secretion, shortened proinsulin half-life, and lowered intracellular proinsulin and insulin levels. This phenotype was accompanied by post-ER proinsulin misprocessing and higher numbers of enlarged insulin granules that contained amorphic material with reduced immunogold staining for mature insulin. Insulin granule exocytosis was accelerated twofold, but the secreted insulin had diminished bioactivity. Moreover, GRP94 knockdown or knockout in β-cells selectively activated protein kinase R-like endoplasmic reticulum kinase (PERK), without increasing apoptosis levels. Finally, GRP94 mRNA was overexpressed in islets from patients with type 2 diabetes. We conclude that GRP94 is a chaperone crucial for proinsulin handling and insulin secretion.
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Affiliation(s)
- Seyed Mojtaba Ghiasi
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tina Dahlby
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Leena Haataja
- Division of Metabolism, Endocrinology, & Diabetes, University of Michigan Medical Center, Ann Arbor, MI
| | - Sólrun Petersen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Mingyu Yang
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Celina Pihl
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Muhammad Saad Khilji
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kristian Klindt
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Oana Cheta
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Marcelo J Perone
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA)-CONICET-Partner Institute of the Max Planck Society, Polo Científico Tecnológico, Buenos Aires, Argentina
| | - Björn Tyrberg
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Clara Prats
- Center for Healthy Ageing, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sebastian Barg
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Anders Tengholm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Peter Arvan
- Division of Metabolism, Endocrinology, & Diabetes, University of Michigan Medical Center, Ann Arbor, MI
| | | | - Michal Tomasz Marzec
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
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11
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Ghiasi SM, Dahllöf MS, Osmai Y, Osmai M, Jakobsen KK, Aivazidis A, Tyrberg B, Perruzza L, Prause MCB, Christensen DP, Fog-Tonnesen M, Lundh M, Grassi F, Chatenoud L, Mandrup-Poulsen T. Regulation of the β-cell inflammasome and contribution to stress-induced cellular dysfunction and apoptosis. Mol Cell Endocrinol 2018; 478:106-114. [PMID: 30121202 DOI: 10.1016/j.mce.2018.08.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [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: 03/13/2018] [Revised: 07/03/2018] [Accepted: 08/04/2018] [Indexed: 12/17/2022]
Abstract
β-Cells may be a source of IL-1β that is produced as inactive pro-IL-1β and processed into biologically-active IL-1β by enzymatic cleavage mediated by the NLRP1-, NLRP3- and NLRC4-inflammasomes. Little is known about the β-cell inflammasomes. NLRP1-expression was upregulated in islet-cells from T2D-patients and by IL-1β+IFNγ in INS-1 cells in a histone-deacetylase dependent manner. NLRP3 was downregulated by cytokines in INS-1 cells. NLRC4 was barely expressed and not regulated by cytokines. High extracellular K+ reduced cytokine-induced apoptosis and NO production and restored cytokine-inhibited accumulated insulin-secretion. Basal inflammasome expression was JNK1-3 dependent. Knock-down of the ASC interaction domain common for NLRP1 and 3 improved insulin secretion and ameliorated IL-1β and/or glucolipotoxicity-induced cell death and reduced cytokine-induced NO-production. Broad inflammasome-inhibition, but not NLRP3-selective inhibition, protected against IL-1β-induced INS-1 cell-toxicity. We suggest that IL-1β causes β-cell toxicity in part by NLRP1 mediated caspase-1-activation and maturation of IL-1β leading to an autocrine potentiation loop.
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Affiliation(s)
- Seyed Mojtaba Ghiasi
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Mattias Salling Dahllöf
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Yama Osmai
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Mirwais Osmai
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Kathrine Kronberg Jakobsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Alexander Aivazidis
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Björn Tyrberg
- Translational Science, Cardiovascular, Renal and Metabolism, IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
| | - Lisa Perruzza
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | | | - Dan Ploug Christensen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Morten Fog-Tonnesen
- Diabetes Biology and Hagedorn Research Institute, Novo Nordisk, Copenhagen, Denmark
| | - Morten Lundh
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Fabio Grassi
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Bellinzona, Switzerland
| | - Lucienne Chatenoud
- Hospital Necker-Enfants Malades, Université Paris Descartes, INSERM, Paris, France
| | - Thomas Mandrup-Poulsen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark.
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12
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Ghiasi SM, Krogh N, Tyrberg B, Mandrup-Poulsen T. The No-Go and Nonsense-Mediated RNA Decay Pathways Are Regulated by Inflammatory Cytokines in Insulin-Producing Cells and Human Islets and Determine β-Cell Insulin Biosynthesis and Survival. Diabetes 2018; 67:2019-2037. [PMID: 30065031 DOI: 10.2337/db18-0073] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 07/23/2018] [Indexed: 11/13/2022]
Abstract
Stress-related changes in β-cell mRNA levels result from a balance between gene transcription and mRNA decay. The regulation of RNA decay pathways has not been investigated in pancreatic β-cells. We found that no-go and nonsense-mediated RNA decay pathway components (RDPCs) and exoribonuclease complexes were expressed in INS-1 cells and human islets. Pelo, Dcp2, Dis3L2, Upf2, and Smg1/5/6/7 were upregulated by inflammatory cytokines in INS-1 cells under conditions where central β-cell mRNAs were downregulated. These changes in RDPC mRNA or corresponding protein levels were largely confirmed in INS-1 cells and rat/human islets. Cytokine-induced upregulation of Pelo, Xrn1, Dis3L2, Upf2, and Smg1/6 was reduced by inducible nitric oxide synthase inhibition, as were endoplasmic reticulum (ER) stress, inhibition of Ins1/2 mRNA, and accumulated insulin secretion. Reactive oxygen species inhibition or iron chelation did not affect RDPC expression. Pelo or Xrn1 knockdown (KD) aggravated, whereas Smg6 KD ameliorated, cytokine-induced INS-1 cell death without affecting ER stress; both increased insulin biosynthesis and medium accumulation but not glucose-stimulated insulin secretion in cytokine-exposed INS-1 cells. In conclusion, RDPCs are regulated by inflammatory stress in β-cells. RDPC KD improved insulin biosynthesis, likely by preventing Ins1/2 mRNA clearance. Pelo/Xrn1 KD aggravated, but Smg6 KD ameliorated, cytokine-mediated β-cell death, possibly through prevention of proapoptotic and antiapoptotic mRNA degradation, respectively.
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Affiliation(s)
- Seyed Mojtaba Ghiasi
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Nicolai Krogh
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen, Denmark
| | - Björn Tyrberg
- Translational Science; Cardiovascular, Renal and Metabolism; and IMED Biotech Unit, AstraZeneca, Gothenburg, Sweden
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13
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Sisino G, Zhou AX, Dahr N, Sabirsh A, Soundarapandian MM, Perera R, Larsson-Lekholm E, Magnone MC, Althage M, Tyrberg B. Long noncoding RNAs are dynamically regulated during β-cell mass expansion in mouse pregnancy and control β-cell proliferation in vitro. PLoS One 2017; 12:e0182371. [PMID: 28796801 PMCID: PMC5552087 DOI: 10.1371/journal.pone.0182371] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 07/17/2017] [Indexed: 11/25/2022] Open
Abstract
Pregnancy is associated with increased β-cell proliferation driven by prolactin. Long noncoding RNAs (lncRNA) are the most abundant RNA species in the mammalian genome, yet, their functional importance is mainly elusive. Aims/hypothesis: This study tests the hypothesis that lncRNAs regulate β-cell proliferation in response to prolactin in the context of β-cell mass compensation in pregnancy. Methods: The expression profile of lncRNAs in mouse islets at day 14.5 of pregnancy was explored by a bioinformatics approach, further confirmed by quantitative PCR at different days of pregnancy, and islet specificity was evaluated by comparing expression in islets versus other tissues. In order to establish the role of the candidate lncRNAs we studied cell proliferation in mouse islets and the MIN6 β-cell line by EdU incorporation and cell count. Results: We found that a group of lncRNAs is differentially regulated in mouse islets at 14.5 days of pregnancy. At different stages of pregnancy, these lncRNAs are dynamically expressed, and expression is prolactin dependent in mouse islets and MIN6 cells. One of those lncRNAs, Gm16308 (Lnc03), is dynamically regulated during pregnancy, prolactin-dependent and islet-enriched. Silencing Lnc03 in primary β-cells and MIN6 cells inhibits, whereas over-expression stimulates, proliferation even in the absence of prolactin, demonstrating that Lnc03 regulates β-cell growth. Conclusions/interpretation: During pregnancy mouse islet proliferation is correlated with dynamic changes of lncRNA expression. In particular, Lnc03 regulates mouse β-cell proliferation and may be a crucial component of β-cell proliferation in β-cell mass adaptation in both health and disease.
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Affiliation(s)
- Giorgia Sisino
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Mölndal, Sweden
| | - Alex-Xianghua Zhou
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Mölndal, Sweden
| | - Niklas Dahr
- Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Alan Sabirsh
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Mölndal, Sweden
| | | | - Ranjan Perera
- Sanford Burnham Prebys Medical Discovery Institute, Orlando, Florida, United States of America
| | | | - Maria Chiara Magnone
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Mölndal, Sweden
| | - Magnus Althage
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Mölndal, Sweden
| | - Björn Tyrberg
- Cardiovascular and Metabolic Diseases, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Mölndal, Sweden
- * E-mail:
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14
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Kyriazis GA, Smith KR, Tyrberg B, Hussain T, Pratley RE. Sweet taste receptors regulate basal insulin secretion and contribute to compensatory insulin hypersecretion during the development of diabetes in male mice. Endocrinology 2014; 155:2112-21. [PMID: 24712876 PMCID: PMC4020927 DOI: 10.1210/en.2013-2015] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
β-Cells rapidly secrete insulin in response to acute increases in plasma glucose but, upon further continuous exposure to glucose, insulin secretion progressively decreases. Although the mechanisms are unclear, this mode of regulation suggests the presence of a time-dependent glucosensory system that temporarily attenuates insulin secretion. Interestingly, early-stage β-cell dysfunction is often characterized by basal (ie, fasting) insulin hypersecretion, suggesting a disruption of these related mechanisms. Because sweet taste receptors (STRs) on β-cells are implicated in the regulation of insulin secretion and glucose is a bona fide STR ligand, we tested whether STRs mediate this sensory mechanism and participate in the regulation of basal insulin secretion. We used mice lacking STR signaling (T1R2(-/-) knockout) and pharmacologic inhibition of STRs in human islets. Mouse and human islets deprived of STR signaling hypersecrete insulin at short-term fasting glucose concentrations. Accordingly, 5-hour fasted T1R2(-/-) mice have increased plasma insulin and lower glucose. Exposure of isolated wild-type islets to elevated glucose levels reduced STR expression, whereas islets from diabetic (db/db) or diet-induced obese mouse models show similar down-regulation. This transcriptional reprogramming in response to hyperglycemia correlates with reduced STR function in these mouse models, leading to insulin hypersecretion. These findings reveal a novel mechanism by which insulin secretion is physiologically regulated by STRs and also suggest that, during the development of diabetes, STR function is compromised by hyperglycemia leading to hyperinsulinemia. These observations further suggest that STRs might be a promising therapeutic target to prevent and treat type 2 diabetes.
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Affiliation(s)
- George A Kyriazis
- Diabetes and Obesity Research Center (G.A.K., K.R.S., B.T., T.H., R.E.P.) Sanford-Burnham Medical Research Institute, Orlando, Florida 32827; Translational Research Institute for Metabolism and Diabetes (G.A.K., R.E.P.), Florida Hospital, Orlando, Florida 32804; and Translational Science (B.T.), Cardiovascular and Metabolic Disease, Mölndal, AstraZeneca, Sweden
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15
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Simon BR, Learman BS, Parlee SD, Scheller EL, Mori H, Cawthorn WP, Ning X, Krishnan V, Ma YL, Tyrberg B, MacDougald OA. Sweet taste receptor deficient mice have decreased adiposity and increased bone mass. PLoS One 2014; 9:e86454. [PMID: 24466105 PMCID: PMC3899259 DOI: 10.1371/journal.pone.0086454] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Accepted: 12/10/2013] [Indexed: 12/16/2022] Open
Abstract
Functional expression of sweet taste receptors (T1R2 and T1R3) has been reported in numerous metabolic tissues, including the gut, pancreas, and, more recently, in adipose tissue. It has been suggested that sweet taste receptors in these non-gustatory tissues may play a role in systemic energy balance and metabolism. Smaller adipose depots have been reported in T1R3 knockout mice on a high carbohydrate diet, and sweet taste receptors have been reported to regulate adipogenesis in vitro. To assess the potential contribution of sweet taste receptors to adipose tissue biology, we investigated the adipose tissue phenotypes of T1R2 and T1R3 knockout mice. Here we provide data to demonstrate that when fed an obesogenic diet, both T1R2 and T1R3 knockout mice have reduced adiposity and smaller adipocytes. Although a mild glucose intolerance was observed with T1R3 deficiency, other metabolic variables analyzed were similar between genotypes. In addition, food intake, respiratory quotient, oxygen consumption, and physical activity were unchanged in T1R2 knockout mice. Although T1R2 deficiency did not affect adipocyte number in peripheral adipose depots, the number of bone marrow adipocytes is significantly reduced in these knockout animals. Finally, we present data demonstrating that T1R2 and T1R3 knockout mice have increased cortical bone mass and trabecular remodeling. This report identifies novel functions for sweet taste receptors in the regulation of adipose and bone biology, and suggests that in these contexts, T1R2 and T1R3 are either dependent on each other for activity or have common independent effects in vivo.
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Affiliation(s)
- Becky R. Simon
- Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Brian S. Learman
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Sebastian D. Parlee
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Erica L. Scheller
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Hiroyuki Mori
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - William P. Cawthorn
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
- Musculoskeletal Research, Lilly Research Laboratories, Indianapolis, Indiana, United States of America
| | - Xiaomin Ning
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Venkatesh Krishnan
- Musculoskeletal Research, Lilly Research Laboratories, Indianapolis, Indiana, United States of America
| | - Yanfei L. Ma
- Musculoskeletal Research, Lilly Research Laboratories, Indianapolis, Indiana, United States of America
| | - Björn Tyrberg
- Cardiovascular and Metabolic Disease, MedImmune LLC, Gaithersburg, Maryland, United States of America
- Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute, Orlando, Florida, United States of America
| | - Ormond A. MacDougald
- Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, Michigan, United States of America
- Molecular & Integrative Physiology, University of Michigan, Ann Arbor, Michigan, United States of America
- Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan, United States of America
- * E-mail:
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16
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Simon BR, Parlee SD, Learman BS, Mori H, Scheller EL, Cawthorn WP, Ning X, Gallagher K, Tyrberg B, Assadi-Porter FM, Evans CR, MacDougald OA. Artificial sweeteners stimulate adipogenesis and suppress lipolysis independently of sweet taste receptors. J Biol Chem 2013; 288:32475-32489. [PMID: 24068707 DOI: 10.1074/jbc.m113.514034] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
G protein-coupled receptors mediate responses to a myriad of ligands, some of which regulate adipocyte differentiation and metabolism. The sweet taste receptors T1R2 and T1R3 are G protein-coupled receptors that function as carbohydrate sensors in taste buds, gut, and pancreas. Here we report that sweet taste receptors T1R2 and T1R3 are expressed throughout adipogenesis and in adipose tissues. Treatment of mouse and human precursor cells with artificial sweeteners, saccharin and acesulfame potassium, enhanced adipogenesis. Saccharin treatment of 3T3-L1 cells and primary mesenchymal stem cells rapidly stimulated phosphorylation of Akt and downstream targets with functions in adipogenesis such as cAMP-response element-binding protein and FOXO1; however, increased expression of peroxisome proliferator-activated receptor γ and CCAAT/enhancer-binding protein α was not observed until relatively late in differentiation. Saccharin-stimulated Akt phosphorylation at Thr-308 occurred within 5 min, was phosphatidylinositol 3-kinase-dependent, and occurred in the presence of high concentrations of insulin and dexamethasone; phosphorylation of Ser-473 occurred more gradually. Surprisingly, neither saccharin-stimulated adipogenesis nor Thr-308 phosphorylation was dependent on expression of T1R2 and/or T1R3, although Ser-473 phosphorylation was impaired in T1R2/T1R3 double knock-out precursors. In mature adipocytes, artificial sweetener treatment suppressed lipolysis even in the presence of forskolin, and lipolytic responses were correlated with phosphorylation of hormone-sensitive lipase. Suppression of lipolysis by saccharin in adipocytes was also independent of T1R2 and T1R3. These results suggest that some artificial sweeteners have previously uncharacterized metabolic effects on adipocyte differentiation and metabolism and that effects of artificial sweeteners on adipose tissue biology may be largely independent of the classical sweet taste receptors, T1R2 and T1R3.
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Affiliation(s)
| | | | | | | | | | - William P Cawthorn
- Departments of Molecular and Integrative Physiology,; Musculoskeletal Research, Lilly Research Laboratories, Indianapolis, Indiana 46285
| | - Xiaomin Ning
- Departments of Molecular and Integrative Physiology
| | | | - Björn Tyrberg
- Cardiovascular and Metabolic Disease, MedImmune LLC, Gaithersburg Headquarters, Gaithersburg, Maryland 20878,; Metabolic Signaling and Disease, Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute, Orlando, Florida 32827
| | | | | | - Ormond A MacDougald
- From the Program in Cellular and Molecular Biology; Departments of Molecular and Integrative Physiology,; Internal Medicine, University of Michigan, Ann Arbor, Michigan 48105,.
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Kyriazis GA, Mosure KR, Soundarapandian MM, Pratley RE, Tyrberg B. “Tasting” fructose with pancreatic beta-cells: modulation of insulin release by sweet taste receptor signaling and its role in metabolic diseases. BMC Proc 2012. [PMCID: PMC3374229 DOI: 10.1186/1753-6561-6-s3-p29] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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18
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Belal C, Ameli NJ, El Kommos A, Bezalel S, Al'Khafaji AM, Mughal MR, Mattson MP, Kyriazis GA, Tyrberg B, Chan SL. The homocysteine-inducible endoplasmic reticulum (ER) stress protein Herp counteracts mutant α-synuclein-induced ER stress via the homeostatic regulation of ER-resident calcium release channel proteins. Hum Mol Genet 2011; 21:963-77. [PMID: 22045699 DOI: 10.1093/hmg/ddr502] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Endoplasmic reticulum (ER) stress has been implicated as an initiator or contributing factor in neurodegenerative diseases. The mechanisms that lead to ER stress and whereby ER stress contributes to the degenerative cascades remain unclear but their understanding is critical to devising effective therapies. Here we show that knockdown of Herp (Homocysteine-inducible ER stress protein), an ER stress-inducible protein with an ubiquitin-like (UBL) domain, aggravates ER stress-mediated cell death induced by mutant α-synuclein (αSyn) that causes an inherited form of Parkinson's disease (PD). Functionally, Herp plays a role in maintaining ER homeostasis by facilitating proteasome-mediated degradation of ER-resident Ca(2+) release channels. Deletion of the UBL domain or pharmacological inhibition of proteasomes abolishes the Herp-mediated stabilization of ER Ca(2+) homeostasis. Furthermore, knockdown or pharmacological inhibition of ER Ca(2+) release channels ameliorates ER stress, suggesting that impaired homeostatic regulation of Ca(2+) channels promotes a protracted ER stress with the consequent activation of ER stress-associated apoptotic pathways. Interestingly, sustained upregulation of ER stress markers and aberrant accumulation of ER Ca(2+) release channels were detected in transgenic mutant A53T-αSyn mice. Collectively, these data establish a causative link between impaired ER Ca(2+) homeostasis and chronic ER stress in the degenerative cascades induced by mutant αSyn and suggest that Herp is essential for the resolution of ER stress through maintenance of ER Ca(2+) homeostasis. Our findings suggest a therapeutic potential in PD for agents that increase Herp levels or its ER Ca(2+)-stabilizing action.
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Affiliation(s)
- Cherine Belal
- The Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
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Tyrberg B, Miles P, Azizian KT, Denzel MS, Nieves ML, Monosov EZ, Levine F, Ranscht B. T-cadherin (Cdh13) in association with pancreatic β-cell granules contributes to second phase insulin secretion. Islets 2011; 3:327-37. [PMID: 21975561 PMCID: PMC3329514 DOI: 10.4161/isl.3.6.17705] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [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] [Indexed: 12/31/2022] Open
Abstract
Glucose homeostasis depends on adequate control of insulin secretion. We report the association of the cell-adhesion and adiponectin (APN)-binding glycoprotein T-cadherin (Cdh13) with insulin granules in mouse and human β-cells. Immunohistochemistry and electron microscopy of islets in situ and targeting of RFP-tagged T-cadherin to GFP-labeled insulin granules in isolated β-cells demonstrate this unusual location. Analyses of T-cadherin-deficient (Tcad-KO) mice show normal islet architecture and insulin content. However, T-cadherin is required for sufficient insulin release in vitro and in vivo. Primary islets from Tcad-KO mice were defective in glucose-induced but not KCl-mediated insulin secretion. In vivo, second phase insulin release in T-cad-KO mice during a hyperglycemic clamp was impaired while acute first phase release was unaffected. Tcad-KO mice showed progressive glucose intolerance by 5 mo of age without concomitant changes in peripheral insulin sensitivity. Our analyses detected no association of APN with T-cadherin on β-cell granules although colocalization was observed on the pancreatic vasculature. These data identify T-cadherin as a novel component of insulin granules and suggest that T-cadherin contributes to the regulation of insulin secretion independently of direct interactions with APN.
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Affiliation(s)
- Björn Tyrberg
- Sanford-Burnham Medical Research Institute; Orlando, FL USA
| | - Philip Miles
- Department of Surgery; UCSD School of Medicine; La Jolla, CA USA
| | | | | | | | | | - Fred Levine
- Sanford-Burnham Medical Research Institute; La Jolla; CA USA
| | - Barbara Ranscht
- Sanford-Burnham Medical Research Institute; La Jolla; CA USA
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20
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Hellerström C, Eizirik D, Andersson A, Pipeleers DG, Sandler S, Delaney CA, Welsh N, Flodström M, Tyrberg B, Håkan Borg LA. Differences between humans and rodents in the susceptibility to pancreatic cell injury. Implications for the pathogenesis of diabetes. Exp Clin Endocrinol Diabetes 2009. [DOI: 10.1055/s-0029-1211918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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21
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Höglund E, Mattsson G, Tyrberg B, Andersson A, Carlsson C. Growth hormone increases beta-cell proliferation in transplanted human and fetal rat islets. JOP 2009; 10:242-248. [PMID: 19454814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE The aim of the study was to increase the number of human islet beta-cells after transplantation with injections of human growth hormone (hGH). INTERVENTIONS Human islets and fetal rat islets were transplanted under the left kidney capsule and under the right kidney capsule, respectively in nude normoglycemic mice which were then given a daily injection of 200 microg hGH for 1-4 weeks. MAIN OUTCOME MEASURE Beta-cell proliferation was determined using thymidine incorporation and the beta-cell area was assessed using light microscopy. RESULTS Mice given hGH increased their body weight one week after transplantation and had a more efficient removal of glucose after 3 and 4 weeks. Treatment with hGH resulted in increased beta-cell proliferation in human and fetal rat beta-cells, and the beta-cell area tended to increase. However, serum insulin concentrations and pancreas insulin content remained unchanged. CONCLUSIONS hGH increased the proliferation of transplanted human beta-cells as well as improving the glucose tolerance of the transplanted mice.
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Affiliation(s)
- Erika Höglund
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
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22
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Andersson A, Carlsson PO, Carlsson C, Olsson R, Nordin A, Johansson M, Palm F, Tyrberg B, Källskog O, Tillmar L, Welsh N, Mattsson G, Jansson L. Promoting islet cell function after transplantation. Cell Biochem Biophys 2009; 40:55-64. [PMID: 15289643 DOI: 10.1385/cbb:40:3:55] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Engraftment (i.e., the adaptation of transplanted pancreatic islets to their new surroundings with regard to revascularization, reinnervation, and reorganization of other stromal compartments) is of crucial importance for the survival and function of the endocrine cells. Previous studies suggest that transplantation induces both vascular and stromal dysfunctions in the implanted islets when compared with endogenous islets. Thus the vascular density and the blood perfusion of islet grafts is decreased and accompanied with a capillary hypertension. This leads to hypoxic conditions, with an associated shift toward anaerobic metabolism in grafted islets. An improved engraftment will prevent or compensate for the vascular/stromal dysfunction seen in transplanted islets and thereby augment survival of the islet implant. By such means the number of islets needed to cure the recipient will be lessened. This will increase the number of patients that can be transplanted with the limited material available.
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Affiliation(s)
- Arne Andersson
- Department of Medical Cell Biology, Biomedical Centre, Uppsala University, Uppsala, Sweden.
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23
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Qian D, Radde-Gallwitz K, Kelly M, Tyrberg B, Kim J, Gao WQ, Chen P. Basic helix-loop-helix gene Hes6 delineates the sensory hair cell lineage in the inner ear. Dev Dyn 2007; 235:1689-700. [PMID: 16534784 PMCID: PMC2810659 DOI: 10.1002/dvdy.20736] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The basic helix-loop-helix (bHLH) gene Hes6 is known to promote neural differentiation in vitro. Here, we report the expression and functional studies of Hes6 in the inner ear. The expression of Hes6 appears to be parallel to that of Math1 (also known as Atoh1), a bHLH gene necessary and sufficient for hair cell differentiation. Hes6 is expressed initially in the presumptive hair cell precursors in the cochlea. Subsequently, the expression of Hes6 is restricted to morphologically differentiated hair cells. Similarly, the expression of Hes6 in the vestibule is in the hair cell lineage. Hes6 is dispensable for hair cell differentiation, and its expression in inner ear hair cells is abolished in the Math1-null animals. Furthermore, the introduction of Hes6 into the cochlea in vitro is not sufficient to promote sensory or neuronal differentiation. Therefore, Hes6 is downstream of Math1 and its expression in the inner ear delineates the sensory lineage. However, the role of Hes6 in the inner ear remains elusive.
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Affiliation(s)
- Dong Qian
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | | | - Michael Kelly
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
| | | | - Jaesang Kim
- Division of Molecular Life Sciences, Ewha Womans University, Seoul, Korea
| | - Wei-Qiang Gao
- Department of Molecular Biology Genentech South San Francisco, CA 94080
| | - Ping Chen
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322
- Author for correspondence: , 404 727-1808 (Tel), 404 727-6256 (Fax)
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24
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Ball AJ, Abrahamsson AE, Tyrberg B, Itkin-Ansari P, Levine F. HES6 reverses nuclear reprogramming of insulin-producing cells following cell fusion. Biochem Biophys Res Commun 2007; 355:331-7. [PMID: 17300753 PMCID: PMC1852427 DOI: 10.1016/j.bbrc.2007.01.153] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2007] [Accepted: 01/28/2007] [Indexed: 11/19/2022]
Abstract
To examine the mechanism by which growth-stimulated pancreatic beta-cells dedifferentiate, somatic cell fusions were performed between MIN6, a highly differentiated mouse insulinoma, and betalox5, a cell line derived from human beta-cells which progressively dedifferentiated in culture. MIN6/betalox5 somatic cells hybrids underwent silencing of insulin expression and a marked decline in PDX1, NeuroD, and MafA, indicating that betalox5 expresses a dominant transacting factor(s) that represses beta-cell differentiation. Expression of Hes1, which inhibits endocrine differentiation was higher in hybrid cells than in parental MIN6 cells. Hes6, a repressor of Hes1, was highly expressed in primary beta-cells as well as MIN6, but was repressed in hybrids. Hes6 overexpression using a retroviral vector led to a decrease in Hes1 levels, an increase in beta-cell transcription factors and partial restoration of insulin expression. We conclude that the balance of Notch activators and inhibitors may play an important role in maintaining the beta-cell differentiated state.
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Affiliation(s)
- Andrew J Ball
- UCSD Department of Pediatrics, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0816, USA
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25
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Hao E, Tyrberg B, Itkin-Ansari P, Lakey JRT, Geron I, Monosov EZ, Barcova M, Mercola M, Levine F. Beta-cell differentiation from nonendocrine epithelial cells of the adult human pancreas. Nat Med 2006; 12:310-6. [PMID: 16491084 DOI: 10.1038/nm1367] [Citation(s) in RCA: 180] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2005] [Accepted: 01/12/2006] [Indexed: 12/26/2022]
Abstract
The nature and even existence of adult pancreatic endocrine stem or progenitor cells is a subject of controversy in the field of beta-cell replacement for diabetes. One place to search for such cells is in the nonendocrine fraction of cells that remain after islet isolation, which consist of a mixture of epithelia and mesenchyme. Culture in G418 resulted in elimination of the mesenchymal cells, leaving a highly purified population of nonendocrine pancreatic epithelial cells (NEPECs). To evaluate their differentiation potential, NEPECs were heritably marked and transplanted under the kidney capsule of immunodeficient mice. When cotransplanted with fetal pancreatic cells, NEPECs were capable of endocrine differentiation. We found no evidence of beta-cell replication or cell fusion that could have explained the appearance of insulin positive cells from a source other than NEPECs. Nonendocrine-to-endocrine differentiation of NEPECs supports the existence of endocrine stem or progenitor cells within the epithelial compartment of the adult human pancreas.
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Affiliation(s)
- Ergeng Hao
- Rebecca and John Moores UCSD Cancer Center, University of California San Diego, 9500 Gilman Drive, MC 0816, La Jolla, California 92093, USA
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26
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Itkin-Ansari P, Marcora E, Geron I, Tyrberg B, Demeterco C, Hao E, Padilla C, Ratineau C, Leiter A, Lee JE, Levine F. NeuroD1 in the endocrine pancreas: Localization and dual function as an activator and repressor. Dev Dyn 2005; 233:946-53. [PMID: 15906379 DOI: 10.1002/dvdy.20443] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The basic helix-loop-helix transcription factor NeuroD1 regulates cell fate in the nervous system but previously has not been considered to function similarly in the endocrine pancreas due to its reported expression in all islet cell types in the newborn mouse. Because we found that NeuroD1 potently represses somatostatin expression in vitro, its pattern of expression was examined in both strains of mice in which lacZ has been introduced into the NeuroD1 locus by homologous recombination. Analysis of adult transgenic mice revealed that NeuroD1 is predominantly expressed in beta-cells and either absent or expressed below the limit of lacZ detection in mature alpha-, delta-, or PP cells. Consistent with a previous report, NeuroD1 colocalizes with glucagon as well as insulin in immature islets of the newborn mouse. However, no colocalization of NeuroD1with somatostatin was detected in the newborn. In vitro, ectopic expression of NeuroD1 in TRM-6/PDX-1, a human pancreatic delta-cell line, resulted in potent repression of somatostatin concomitant with induction of the beta-cell hormones insulin and islet amyloid polypeptide. Additionally, NeuroD1 induced expression of Nkx2.2, a transcription factor expressed in beta- but not delta-cells. Transfection studies using insulin and somatostatin promoters confirm the ability of NeuroD1 to act as both a transcriptional repressor and activator in the same cell, suggesting a more complex role for NeuroD1 in the establishment and/or maintenance of mature endocrine cells than has been recognized previously.
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Affiliation(s)
- P Itkin-Ansari
- Cancer Center, University of California, San Diego, School of Medicine, Stem Cell Program, The Burnham Institute, La Jolla, California 92093-0816, USA.
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27
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Andersson A, Carlsson PO, Carlsson C, Olsson R, Nordin A, Johansson M, Palm F, Tyrberg B, Källskog Ö, Tillmar L, Welsh N, Mattsson G, Jansson L. Promoting Islet Cell Function After Transplantation. Cell Biochem Biophys 2004. [DOI: 10.1385/cbb:40:3s:055] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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28
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Demeterco C, Itkin-Ansari P, Tyrberg B, Ford LP, Jarvis RA, Levine F. c-Myc controls proliferation versus differentiation in human pancreatic endocrine cells. J Clin Endocrinol Metab 2002; 87:3475-85. [PMID: 12107268 DOI: 10.1210/jcem.87.7.8700] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Using immortalized human pancreatic endocrine cell lines, we have shown previously that differentiation into hormone-expressing cells requires cell-cell contact acting in synergy with the homeodomain transcription factor pancreatic duodenal homeobox-1 (PDX-1). Although differentiation is associated with a decrease in cell proliferation, the mechanisms behind this relationship are not known. Using TRM-6, a delta cell line, and betalox5, a beta-cell line, we show here that cell-cell contact and subsequent endocrine differentiation lead to a down-regulation of the c-myc protooncogene. Overexpression of c-Myc obtained with an inducible c-Myc-estrogen receptor fusion protein results in an increase in cell proliferation and the ablation of hormone expression. Moreover, we show that although c-Myc is expressed in a subset of cells from the human fetal and adult pancreas, it is absent in differentiated endocrine cells. The mechanism by which c-Myc interferes with hormone expression may be through effects on the homeodomain transcription factor PDX-1, as immunostaining for PDX-1 in cells with activated c-Myc revealed a redistribution of PDX-1 from the nucleus to the cytoplasm. These results suggest that c-Myc plays a central role in a cell-cell contact-mediated switch mechanism by which cell division vs. differentiation in endocrine cells is determined.
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Affiliation(s)
- Carla Demeterco
- Cancer Center, University of California-San Diego, 1st Floor Building 7, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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29
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Tyrberg B, Anachkov KA, Dib SA, Wang-Rodriguez J, Yoon KH, Levine F. Islet expression of the DNA repair enzyme 8-oxoguanosine DNA glycosylase (Ogg1) in human type 2 diabetes. BMC Endocr Disord 2002; 2:2. [PMID: 12003641 PMCID: PMC111186 DOI: 10.1186/1472-6823-2-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2002] [Accepted: 04/25/2002] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND: It has become increasingly clear that beta-cell failure plays a critical role in the pathogenesis of type 2 diabetes. Free-radical mediated beta-cell damage has been intensively studied in type 1 diabetes, but not in human type 2 diabetes. Therefore, we studied the protein expression of the DNA repair enzyme Ogg1 in pancreases from type 2 diabetics. Ogg1 was studied because it is the major enzyme involved in repairing 7,8-dihydro-8-oxoguanosine DNA adducts, a lesion previously observed in a rat model of type 2 diabetes. Moreover, in a gene expression screen, Ogg1 was over-expressed in islets from a human type 2 diabetic. METHODS: Immunofluorescent staining of Ogg1 was performed on pancreatic specimens from healthy controls and patients with diabetes for 2-23 years. The intensity and islet area stained for Ogg1 was evaluated by semi-quantitative scoring. RESULTS: Both the intensity and the area of islet Ogg1 staining were significantly increased in islets from the type 2 diabetic subjects compared to the healthy controls. A correlation between increased Ogg1 fluorescent staining intensity and duration of diabetes was also found. Most of the staining observed was cytoplasmic, suggesting that mitochondrial Ogg1 accounts primarily for the increased Ogg1 expression. CONCLUSION: We conclude that oxidative stress related DNA damage may be a novel important factor in the pathogenesis of human type 2 diabetes. An increase of Ogg1 in islet cell mitochondria is consistent with a model in which hyperglycemia and consequent increased beta-cell oxidative metabolism lead to DNA damage and the induction of Ogg1 expression.
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Affiliation(s)
| | - Kamen A Anachkov
- Department of Pathology, Sector Anatomic Pathology, Military Medical Academy, Sofia, Bulgaria
| | - Sergio A Dib
- Brazil Division of Endocrinology, Department of Medicine, Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, SP, Brazil
| | | | - Kun-Ho Yoon
- Kangnam St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Fred Levine
- UCSD Cancer Center, La Jolla, CA 92037-0912, USA
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30
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Tyrberg B, Levine F. Current and future treatment strategies for type 2 diabetes: the beta-cell as a therapeutic target. Curr Opin Investig Drugs 2001; 2:1568-74. [PMID: 11763159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Diabetes affects millions of people worldwide. The most common variants are type 1 diabetes with autoimmune destruction of the pancreatic beta-cells and type 2 diabetes with peripheral insulin resistance and beta-cell dysfunction. In spite of tremendous research, current pharmacological regimens are still sub-optimal for adequate blood glucose control. As a consequence, patients with diabetes are at significant risk for development of serious long-term complications, such as blindness and kidney disease. This review will discuss present and future strategies for the treatment of type 2 diabetes with a focus on the more recently recognized problems of beta-cell dysfunction and loss. The treatment strategies presented include promotion of beta-cell proliferation and differentiation by glucagon-like peptide 1 receptor agonists.
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Affiliation(s)
- B Tyrberg
- UCSD Cancer Center, La Jolla, CA 92037-0912, USA.
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Abstract
BACKGROUND The aim was to measure the capillary blood pressure in transplanted human islets. METHODS Human islets were isolated at the Central Unit of the beta-cell Transplant in Brussels, Belgium. After transport to our laboratory, the islets were implanted under the renal capsule of normoglycemic nude mice. Two weeks later the capillary and venous blood pressures in the islet graft and adjacent renal parenchyma were measured with a micropuncture technique. RESULTS Capillary blood pressure was approximately 5-8 mmHg in both graft and renal capillaries: twice as high as in native islets. Venous blood pressures were similar (4-5 mmHg) in the veins draining the graft and in the renal interlobular veins. All veins leading from the graft emptied into the renal parenchyma, that is, into interlobular veins. CONCLUSIONS The capillary hypertension seen in transplanted human islets is probably necessary to secure adequate drainage through the renal veins. Whether this contributes to the poor results of long-term islet graft survival is unknown.
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Affiliation(s)
- L Jansson
- Department of Medical Cell Biology, Uppsala University, Sweden.
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Abstract
The beta-cell toxin alloxan, which produces oxygen radicals, is a model substance in studies of type 1 diabetes. Recently, human beta-cells have been found to be relatively resistant to this toxin. To clarify species differences in alloxan diabetogenicity, and oxygen radical toxicity, mouse, rat, rabbit, dog, pig, human and guinea pig islets have been studied after alloxan exposure. Using a standardized in vivo model, where islets were transplanted to nude mice, the different islets were compared. The results demonstrated that mouse and rat islet grafts were morphologically disturbed by alloxan and ROS. Rabbit and dog islet graft morphology was reasonably intact; and human, porcine, and guinea pig islet grafts were all well preserved. Furthermore, ultrastructural signs of apoptosis and necrosis, disturbances in the insulin secretory pattern during and after an alloxan perifusion, and islet lysosomal enzyme activities were studied in vitro in islets from some species. Guinea pig beta-cells were affected by alloxan, but a regeneration process compensated for the observed apoptotic and necrotic cell death. Human islets did not show any signs of alloxan-induced damage in the different models studied. Finally, no correlation between high alloxan sensitivity and high lysosomal enzyme activity was found. Thus, the beta-cell lysosomes are hardly specific targets for alloxan.
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Affiliation(s)
- B Tyrberg
- Department of Medical Cell Biology, Uppsala University, Uppsala, SE-751 23, Sweden.
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de la Tour D, Halvorsen T, Demeterco C, Tyrberg B, Itkin-Ansari P, Loy M, Yoo SJ, Hao E, Bossie S, Levine F. Beta-cell differentiation from a human pancreatic cell line in vitro and in vivo. Mol Endocrinol 2001; 15:476-83. [PMID: 11222748 DOI: 10.1210/mend.15.3.0604] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cell transplantation therapy for diabetes is limited by an inadequate supply of cells exhibiting glucose-responsive insulin secretion. To generate an unlimited supply of human beta-cells, inducibly transformed pancreatic beta-cell lines have been created by expression of dominant oncogenes. The cell lines grow indefinitely but lose differentiated function. Induction of beta-cell differentiation was achieved by stimulating the signaling pathways downstream of the transcription factor PDX-1, cell-cell contact, and the glucagon-like peptide (GLP-1) receptor. Synergistic activation of those pathways resulted in differentiation into functional beta-cells exhibiting glucose-responsive insulin secretion in vitro. Both oncogene-expressing and oncogene-deleted cells were transplanted into nude mice and found to exhibit glucose-responsive insulin secretion in vivo. The ability to grow unlimited quantities of human beta-cells is a major step toward developing a cell transplantation therapy for diabetes.
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Affiliation(s)
- D de la Tour
- University of California San Diego Cancer Center La Jolla, California 92093-0912, USA
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Tyrberg B, Ustinov J, Otonkoski T, Andersson A. Stimulated endocrine cell proliferation and differentiation in transplanted human pancreatic islets: effects of the ob gene and compensatory growth of the implantation organ. Diabetes 2001; 50:301-7. [PMID: 11272140 DOI: 10.2337/diabetes.50.2.301] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Neogenesis is crucial for the maintenance of beta-cell mass in the human pancreas and possibly for the outcome of clinical islet transplantation. To date, no studies have reported a stimulation of human beta-cell neogenesis in vivo. Therefore, we investigated whether human alpha-, beta-, and duct cell growth can be stimulated when human islets are xenotransplanted to obese hyperglycemic-hyperinsulinemic ob/ob mice immunosuppressed with anti-lymphocyte serum. Moreover, we wanted to study whether beta-cell growth and duct-to-beta-cell differentiation were induced in the hepatocyte growth factor (HGF)-dependent compensatory kidney growth model. For that purpose, we evaluated human islets grafted to nude (nu/nu) mice before uninephrectomy of the contralateral kidney for DNA-synthesis and duct cell expression of the beta-cell-specific transcription factor Nkx 6.1 as an estimate of differentiation. Human islet grafts were well preserved after 2 weeks when transplanted to ob/ob mice during anti-lymphocyte immunosuppression. Both human beta-cells (P < 0.01) and duct cells (P < 0.001) were growth stimulated when islets were transplanted to ob/ob mice. We also observed a correlation between increased duct cell proliferation and increased organ donor age (P = 0.02). Moreover, duct (P < 0.05) and beta-cell (P < 0.05) proliferation, as well as duct cell Nkx 6.1 expression (P < 0.05), were enhanced by the compensatory kidney growth after uninephrectomy. We conclude that it is possible to stimulate human beta-cell neogenesis in vivo, provided that the recipient carries certain growth-stimulatory traits. Furthermore, it seems that duct cell proliferation increases with increasing organ donor age. Altogether, these data and previous results from our laboratory suggest that human beta-cell neogenesis becomes more dependent on differentiation and less dependent on proliferation with increasing age.
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Affiliation(s)
- B Tyrberg
- Department of Medical Cell Biology, Uppsala University, Sweden.
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Carlsson PO, Andersson A, Carlsson C, Hellerström C, Höglund E, King A, Källskog O, Liss P, Mattsson G, Olsson R, Palm F, Sandler S, Tyrberg B, Jansson L. Engraftment and growth of transplanted pancreatic islets. Ups J Med Sci 2000; 105:107-23. [PMID: 11095108 DOI: 10.1517/03009734000000058] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Transplantation of pancreatic islets may provide a cure for type 1 diabetes. However, this treatment can currently be offered only to very few patients. To improve transplantation success we need to understand better the mechanisms of how the implanted islets survive, grow and/or maintain adequate function. We herein report on our studies to evaluate the factors responsible for the engraftment, i.e. revascularization, reinnervation etc., of transplanted islets and relate these factors to the metabolism and growth of the islets. Graft metabolism can be monitored by microdialysis probes that allow for the measurement of minute amounts of islet metabolites and hormonal products. Growth of the endocrine cells can be stimulated both in vitro before implantation and in vivo post-transplantation. Another problem is rejection of transplanted islets, which may be overcome by the microencapsulation of islets. The knowledge gained by the present studies will enable us to elucidate the optimal treatment of islets to ensure a maximal survival of the transplanted islets, and may be applied also to clinical islet transplantation.
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Affiliation(s)
- P O Carlsson
- Department of Medical Cell Biology, Uppsala University, Sweden
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Tyrberg B, Eizirik DL, Marklund SL, Olejnicka B, Madsen OD, Andersson A. Human islets in mixed islet grafts protect mouse pancreatic beta-cells from alloxan toxicity. Pharmacol Toxicol 1999; 85:269-75. [PMID: 10628902 DOI: 10.1111/j.1600-0773.1999.tb02021.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We have previously shown that human beta-cells are resistant to the toxic effects of alloxan. In order to further clarify this characteristic of human islets, we investigated whether these cells might transfer their alloxan resistance to alloxan-sensitive rat or mouse islets. Islets from two species (human-mouse or rat-mouse) were mixed into one graft, which was implanted into the subcapsular kidney space of nude mice. Alloxan or saline was injected intravenously two weeks after implantation and one week thereafter the mice were killed. The number of grafted and endogenous beta-cells were evaluated by a semi-quantitative method after immunohistochemistry. Human islet production of the scavenging enzymes extracellular superoxide dismutase and plasma glutathione peroxidase were analyzed with ELISA-techniques, and mouse and human islet hydrogen peroxide breakdown activity were monitored with a horseradish peroxidase-dependent assay. Mouse beta-cells transplanted together with human islets were protected against alloxan cytotoxicity. Rat islets did not protect mouse beta-cells against alloxan, suggesting that the mixing procedure as such did not impose the protection. Production of extracellular superoxide dismutase and plasma glutathione peroxidase by human islets was very low. Moreover, H2O2 breakdown in vitro, did not differ between human and mouse islets. Alloxan-insensitive human islets protect mouse beta-cells against alloxan-induced lesions, suggesting that yet to be identified extracellular factors are involved in human islet resistance to alloxan toxicity.
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Affiliation(s)
- B Tyrberg
- Department of Medical Cell Biology, Uppsala University, Sweden.
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Flodström M, Tyrberg B, Eizirik DL, Sandler S. Reduced sensitivity of inducible nitric oxide synthase-deficient mice to multiple low-dose streptozotocin-induced diabetes. Diabetes 1999; 48:706-13. [PMID: 10102685 DOI: 10.2337/diabetes.48.4.706] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Nitric oxide (NO), synthesized by the inducible isoform of nitric oxide synthase (iNOS), has been proposed as a mediator of immune-induced beta-cell destruction in type 1 diabetes. To evaluate the role of iNOS for beta-cell dysfunction and death, we investigated the sensitivity of beta-cells from mice genetically deficient in this enzyme (iNOS-/-, background C57BL/6x129SvEv, H-2b) both to interleukin (IL)-1beta-induced beta-cell dysfunction in vitro and to multiple low-dose streptozotocin (MLDS)-induced diabetes in vivo. Exposure of islets isolated from C57BL/6 mice to IL-1beta for 24 h in vitro resulted in an induction of iNOS mRNA expression, an increase in nitrite formation, and a decrease in insulin release and proinsulin biosynthesis as compared with untreated C57BL/6 islets. IL-1beta failed to induce iNOS mRNA expression and increase nitrite formation by islets isolated from iNOS knockout mice (iNOS-/-), and no impairment in islet function was observed. The iNOS-/- mice showed a reduced incidence of hyperglycemia after treatment with MLDS as compared with wild-type C57BL/6 (H-2b) and 129 SvEv (H-2b) mice. On day 21 after the first streptozotocin (STZ) injection, 75% of the C57BL/6 mice and 100% of the 129SvEv mice had blood glucose levels >11 mmol/l, whereas the corresponding number for iNOS-/- mice was only 23%. This protection was not due to a delay in the onset of hyperglycemia, since no increase in number of hyperglycemic iNOS-/- mice was observed when the animals were followed up to 42 days. Moreover, islets isolated from iNOS-/- mice were susceptible to the in vitro deleterious effects of STZ. In conclusion, the present study provides evidence that iNOS may contribute to beta-cell damage after exposure to IL-1beta in vitro and treatment with MLDS in vivo.
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Affiliation(s)
- M Flodström
- Department of Medical Cell Biology, Uppsala University, Sweden.
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Abstract
Reactive oxygen intermediates (ROI) may be involved in the destruction of pancreatic beta-cells during the development of insulin-dependent diabetes mellitus (IDDM). To investigate the possible role of lysosomes in this process, normal mouse beta-cells were cultured as monolayers at D-glucose concentrations of 1.6 (pronounced crinophagy), 11 or 28 mM (minimal crinophagy), subjected to a low level of oxidative stress and returned to standard culture conditions. Some cultures were exposed to desferrioxamine (Des) before the oxidative stress. As a result of such stress, many of the cells' lysosomes ruptured with consequent apoptosis or necrosis. Cells kept at 1.6 mM glucose were rich in secretory granules, showed crinophagy/autophagy, were very sensitive to oxidative stress, and had the least stable lysosomes. Cells kept at 28 mM glucose did not show crinophagy, contained fewer secretory granules, were less sensitive to oxidative stress, and had more stable lysosomes. Des-treated cells behaved almost as cells not exposed to oxidative stress at all. The findings suggest that iron may occur together with zinc within the secretory granules and that it sensitizes crinophagic lysosomes to oxidative stress. The stress that was applied in this study may be comparable to what occurs within the vicinity of activated macrophages during autoimmune insulitis.
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Affiliation(s)
- B T Olejnicka
- Division of Pathology II, Faculty of Health Sciences, Linköping University, Sweden.
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Tyrberg B, Eizirik DL, Hellerström C, Pipeleers DG, Andersson A. Human pancreatic beta-cell deoxyribonucleic acid-synthesis in islet grafts decreases with increasing organ donor age but increases in response to glucose stimulation in vitro. Endocrinology 1996; 137:5694-9. [PMID: 8940401 DOI: 10.1210/endo.137.12.8940401] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Human pancreatic beta-cell proliferation may be crucial for the success of islet transplantation. The aim of this study was to test the hypothesis that adult human beta-cells proliferate in vitro and in vivo and respond with increased rates of replication to factors known to promote rodent islet-cell proliferation, i.e. glucose, human recombinant GH, and FCS. For this purpose, human islets were prepared from a total of 19 adult heart-beating organ donors and cultured for 48 h with or without the additives described above. 3H-thymidine was added to the medium during the last 60 min of culture. After immunohistochemical staining for insulin and autoradiography, the labeling index (LI; i.e. % of labeled beta-cells over total number of beta-cells) was estimated by light microscopy. Islets also were transplanted under the kidney capsule of normal or alloxan-diabetic nude mice. After 2 weeks, 3H-thymidine was injected and the islet grafts prepared for determination of LI, as described above. Islets cultured at 5.6 mM glucose showed an increased beta-cell proliferation compared with islets cultured at 2.8 mM glucose (P < 0.05). However, culture at 11 mM glucose failed to further increase beta-cell proliferation. Addition of GH (1 microg/ml) to the medium, in the presence of 1% FCS and 5.6 mM glucose, did not influence the rate of beta-cell proliferation. In islets transplanted to hyperglycemic nude mice, beta-cell proliferation was similar to that observed in islets grafted into normoglycemic nude mice. Proliferation, however, decreased with increasing organ donor age. This study shows that pancreatic beta-cells from adult man are able to proliferate both in vitro and in vivo. Moreover, beta-cells from adult human donors respond with increased proliferation to glucose in vitro and show a decreased proliferation in vivo with increasing donor age.
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Affiliation(s)
- B Tyrberg
- Department of Medical Cell Biology, Uppsala University, Sweden.
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Delaney CA, Tyrberg B, Bouwens L, Vaghef H, Hellman B, Eizirik DL. Sensitivity of human pancreatic islets to peroxynitrite-induced cell dysfunction and death. FEBS Lett 1996; 394:300-6. [PMID: 8830662 DOI: 10.1016/0014-5793(96)00977-5] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Nitric oxide and peroxynitrite (generated by the reaction of nitric oxide with the superoxide anion) may both be mediators of beta-cell damage in early insulin-dependent diabetes mellitus. We observed that acute exposure of primary cultured human pancreatic islets to peroxynitrite results in a significant decrease in glucose oxidation and islet retrieval. DNA strand breaks in single human and rat islet cells are detectable after acute peroxynitrite exposure, followed by a decrease in islet cell survival after 1 h and 24 h. Cell death appeared to occur via a toxic cell death mechanism (necrosis) rather than apoptosis, as suggested by vital staining and ultrastructural evidence of early membrane and organelle degradation, mitochondrial swelling and loss of matrix. This study demonstrates for the first time that cultured human pancreatic islets are susceptible to the noxious effects of peroxynitrite.
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Affiliation(s)
- C A Delaney
- Department of Medical Cell Biology, Uppsala University, Sweden. Carol
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