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Costes S, Huang CJ, Gurlo T, Daval M, Matveyenko AV, Rizza RA, Butler AE, Butler PC. Erratum. β-Cell Dysfunctional ERAD/Ubiquitin/Proteasome System in Type 2 Diabetes Mediated by Islet Amyloid Polypeptide-Induced UCH-L1 Deficiency. Diabetes 2011;60:227-238. Diabetes 2023; 72:1881. [PMID: 37683136 PMCID: PMC10658060 DOI: 10.2337/db23-er12] [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: 09/10/2023]
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Wang Z, Archang M, Gurlo T, Wong E, Fraser SE, Butler PC. Application of fluorescence lifetime imaging microscopy to monitor glucose metabolism in pancreatic islets in vivo. Biomed Opt Express 2023; 14:4170-4178. [PMID: 37799700 PMCID: PMC10549748 DOI: 10.1364/boe.493722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/09/2023] [Accepted: 07/10/2023] [Indexed: 10/07/2023]
Abstract
Glucose stimulated insulin secretion is mediated by glucose metabolism via oxidative phosphorylation generating ATP that triggers membrane depolarization and exocytosis of insulin. In stressed beta cells, glucose metabolism is remodeled, with enhanced glycolysis uncoupled from oxidative phosphorylation, resulting in the impaired glucose-mediated insulin secretion characteristic of diabetes. Relative changes in glycolysis and oxidative phosphorylation can be monitored in living cells using the 3-component fitting approach of fluorescence lifetime imaging microscopy (FLIM). We engrafted pancreatic islets onto the iris to permit in vivo FLIM monitoring of the trajectory of glucose metabolism. The results show increased oxidative phosphorylation of islet cells (∼90% beta cells) in response to hyperglycemia; in contrast red blood cells traversing the islets maintained exclusive glycolysis as expected in the absence of mitochondria.
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Affiliation(s)
- Zhongying Wang
- Larry L. Hillblom Islet Research Center,
University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Maani Archang
- Larry L. Hillblom Islet Research Center,
University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Tatyana Gurlo
- Larry L. Hillblom Islet Research Center,
University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Elaine Wong
- Larry L. Hillblom Islet Research Center,
University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA
| | - Scott E. Fraser
- Department of Biological Sciences, Bridge Institute, David Dornsife College of Letters, Arts and Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Peter C. Butler
- Larry L. Hillblom Islet Research Center,
University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA
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Gurlo T, Prakash TP, Wang Z, Archang M, Pei L, Rosenberger M, Pirie E, Lee RG, Butler PC. Efficacy of IAPP suppression in mouse and human islets by GLP-1 analogue conjugated antisense oligonucleotide. Front Mol Biosci 2023; 10:1096286. [PMID: 36814640 PMCID: PMC9939749 DOI: 10.3389/fmolb.2023.1096286] [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] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 01/20/2023] [Indexed: 02/09/2023] Open
Abstract
Insulin resistance is the major risk factor for Type 2 diabetes (T2D). In vulnerable individuals, insulin resistance induces a progressive loss of insulin secretion with islet pathology revealing a partial deficit of beta cells and islet amyloid derived from islet amyloid polypeptide (IAPP). IAPP is co-expressed and secreted with insulin by beta cells, expression of both proteins being upregulated in response to insulin resistance. If IAPP expression exceeds the threshold for clearance of misfolded proteins, beta cell failure occurs exacerbated by the action of IAPP toxicity to compromise the autophagy lysosomal pathway. We postulated that suppression of IAPP expression by an IAPP antisense oligonucleotide delivered to beta cells by the GLP-1 agonist exenatide (eGLP1-IAPP-ASO) is a potential disease modifying therapy for T2D. While eGLP1-IAPP-ASO suppressed mouse IAPP and transgenic human IAPP expression in mouse islets, it had no discernable effects on IAPP expression in human islets under the conditions studied. Suppression of transgenic human IAPP expression in mouse islets attenuated disruption of the autophagy lysosomal pathway in beta cells, supporting the potential of this strategy.
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Affiliation(s)
- Tatyana Gurlo
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States,*Correspondence: Tatyana Gurlo, ; Peter C. Butler,
| | | | - Zhongying Wang
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Maani Archang
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Lina Pei
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Madeline Rosenberger
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Elaine Pirie
- IONIS Pharmaceuticals, Carlsbad, CA, United States
| | | | - Peter C. Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States,*Correspondence: Tatyana Gurlo, ; Peter C. Butler,
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Butler PC, Gale EA. Reversing type 1 diabetes with stem cell-derived islets: a step closer to the dream? J Clin Invest 2022; 132:e158305. [PMID: 35104802 PMCID: PMC8803316 DOI: 10.1172/jci158305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- Peter C. Butler
- Larry Hillblom Islet Research Center, Department of Medicine, UCLA, Los Angeles, California, USA
| | - Edwin A.M. Gale
- Diabetes and Metabolism, University of Bristol, Bristol, United Kingdom
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Blencowe M, Furterer A, Wang Q, Gao F, Rosenberger M, Pei L, Nomoto H, Mawla AM, Huising MO, Coppola G, Yang X, Butler PC, Gurlo T. IAPP-induced beta cell stress recapitulates the islet transcriptome in type 2 diabetes. Diabetologia 2022; 65:173-187. [PMID: 34554282 PMCID: PMC8660728 DOI: 10.1007/s00125-021-05569-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 07/30/2021] [Indexed: 01/22/2023]
Abstract
AIMS/HYPOTHESIS Type 2 diabetes is characterised by islet amyloid and toxic oligomers of islet amyloid polypeptide (IAPP). We posed the questions, (1) does IAPP toxicity induce an islet response comparable to that in humans with type 2 diabetes, and if so, (2) what are the key transcriptional drivers of this response? METHODS The islet transcriptome was evaluated in five groups of mice: beta cell specific transgenic for (1) human IAPP, (2) rodent IAPP, (3) human calpastatin, (4) human calpastatin and human IAPP, and (5) wild-type mice. RNA sequencing data was analysed by differential expression analysis and gene co-expression network analysis to establish the islet response to adaptation to an increased beta cell workload of soluble rodent IAPP, the islet response to increased expression of oligomeric human IAPP, and the extent to which the latter was rescued by suppression of calpain hyperactivation by calpastatin. Rank-rank hypergeometric overlap analysis was used to compare the transcriptome of islets from human or rodent IAPP transgenic mice vs humans with prediabetes or type 2 diabetes. RESULTS The islet transcriptomes in humans with prediabetes and type 2 diabetes are remarkably similar. Beta cell overexpression of soluble rodent or oligomer-prone human IAPP induced changes in islet transcriptome present in prediabetes and type 2 diabetes, including decreased expression of genes that confer beta cell identity. Increased expression of human IAPP, but not rodent IAPP, induced islet inflammation present in prediabetes and type 2 diabetes in humans. Key mediators of the injury responses in islets transgenic for human IAPP or those from individuals with type 2 diabetes include STAT3, NF-κB, ESR1 and CTNNB1 by transcription factor analysis and COL3A1, NID1 and ZNF800 by gene regulatory network analysis. CONCLUSIONS/INTERPRETATION Beta cell injury mediated by IAPP is a plausible mechanism to contribute to islet inflammation and dedifferentiation in type 2 diabetes. Inhibition of IAPP toxicity is a potential therapeutic target in type 2 diabetes.
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Affiliation(s)
- Montgomery Blencowe
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, USA
- Molecular, Cellular, and Integrative Physiology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA, USA
| | - Allison Furterer
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Qing Wang
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Fuying Gao
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Madeline Rosenberger
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Lina Pei
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Hiroshi Nomoto
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Alex M Mawla
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, CA, USA
| | - Mark O Huising
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California, Davis, Davis, CA, USA
| | - Giovanni Coppola
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
- Department of Neurology, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Xia Yang
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, USA
- Molecular, Cellular, and Integrative Physiology Interdepartmental Program, University of California, Los Angeles, Los Angeles, CA, USA
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Tatyana Gurlo
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA.
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Abstract
β cells in the hyperglycemic environment of diabetes have marked changes in phenotype and function that are largely reversible if glucose levels can be returned to normal. A leading hypothesis is that these changes are caused by the elevated glucose levels leading to the concept of glucose toxicity. Support for the glucose toxicity hypothesis is largely circumstantial, but little progress has been made in defining the responsible mechanisms. Then questions emerge that are difficult to answer. In the very earliest stages of diabetes development, there is a dramatic loss of glucose-induced first-phase insulin release (FPIR) with only trivial elevations of blood glucose levels. A related question is how impaired insulin action on target tissues such as liver, muscle and fat can cause increased insulin secretion. The existence of a sophisticated feedback mechanism between insulin secretion and insulin action on peripheral tissues driven by glucose has been postulated, but it has been difficult to measure increases in blood glucose levels that might have been expected. These complexities force us to challenge the simplicity of the glucose toxicity hypothesis and feedback mechanisms. It may turn out that glucose is somehow driving all of these changes, but we must develop new questions and experimental approaches to test the hypothesis.
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Affiliation(s)
- Gordon C Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA.
| | - Peter C Butler
- Larry l. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Susan Bonner-Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
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Wang Z, Gurlo T, Matveyenko AV, Elashoff D, Wang P, Rosenberger M, Junge JA, Stevens RC, White KL, Fraser SE, Butler PC. Live-cell imaging of glucose-induced metabolic coupling of β and α cell metabolism in health and type 2 diabetes. Commun Biol 2021; 4:594. [PMID: 34012065 PMCID: PMC8134470 DOI: 10.1038/s42003-021-02113-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 04/15/2021] [Indexed: 12/18/2022] Open
Abstract
AbstractType 2 diabetes is characterized by β and α cell dysfunction. We used phasor-FLIM (Fluorescence Lifetime Imaging Microscopy) to monitor oxidative phosphorylation and glycolysis in living islet cells before and after glucose stimulation. In healthy cells, glucose enhanced oxidative phosphorylation in β cells and suppressed oxidative phosphorylation in α cells. In Type 2 diabetes, glucose increased glycolysis in β cells, and only partially suppressed oxidative phosphorylation in α cells. FLIM uncovers key perturbations in glucose induced metabolism in living islet cells and provides a sensitive tool for drug discovery in diabetes.
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Affiliation(s)
- Peter C Butler
- From the Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles
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Zhang X, Carter SD, Singla J, White KL, Butler PC, Stevens RC, Jensen GJ. Visualizing insulin vesicle neighborhoods in β cells by cryo-electron tomography. Sci Adv 2020; 6:eabc8258. [PMID: 33298442 PMCID: PMC7725471 DOI: 10.1126/sciadv.abc8258] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 10/22/2020] [Indexed: 05/04/2023]
Abstract
Subcellular neighborhoods, comprising specific ratios of organelles and proteins, serve a multitude of biological functions and are of particular importance in secretory cells. However, the role of subcellular neighborhoods in insulin vesicle maturation is poorly understood. Here, we present single-cell multiple distinct tomogram acquisitions of β cells for in situ visualization of distinct subcellular neighborhoods that are involved in the insulin vesicle secretory pathway. We propose that these neighborhoods play an essential role in the specific function of cellular material. In the regions where we observed insulin vesicles, a measurable increase in both the fraction of cellular volume occupied by vesicles and the average size (diameter) of the vesicles was apparent as sampling moved from the area near the nucleus toward the plasma membrane. These findings describe the important role of the nanometer-scale organization of subcellular neighborhoods on insulin vesicle maturation.
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Affiliation(s)
- Xianjun Zhang
- Department of Biological Sciences, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Stephen D Carter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Jitin Singla
- Department of Biological Sciences, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Kate L White
- Department of Biological Sciences, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Peter C Butler
- Larry Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Raymond C Stevens
- Department of Biological Sciences, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA.
- Department of Chemistry, Bridge Institute, USC Michelson Center for Convergent Bioscience, University of Southern California, Los Angeles, CA 90089, USA
| | - Grant J Jensen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
- Howard Hughes Medical Institute (HHMI), California Institute of Technology, Pasadena, CA 91125, USA
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Moin ASM, Cory M, Gurlo T, Saisho Y, Rizza RA, Butler PC, Butler AE. Pancreatic alpha-cell mass across adult human lifespan. Eur J Endocrinol 2020; 182:219-231. [PMID: 31821160 PMCID: PMC6944979 DOI: 10.1530/eje-19-0844] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [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: 10/20/2019] [Accepted: 12/09/2019] [Indexed: 12/21/2022]
Abstract
AIM To establish pancreatic alpha-cell mass in lean, non-diabetic humans over the adult lifespan, performed as a follow-up study to beta-cell mass across the adult human lifespan. METHODS We examined human pancreatic autopsy tissue from 66 lean, non-diabetic individuals aged from 30 to 102 years, grouped into deciles: 3rd (30-39 years), 4th (40-49 years), 5th (50-59 years), 6th (60-69 years), 7th (70-79 years), 8th (80-89 years) and 9th deciles (90+ years). Sections of pancreas were immunostained for glucagon and analyzed for fractional alpha-cell area. Population-based pancreatic volume data were used to calculate alpha-cell mass. RESULTS With advanced age, the exocrine pancreas undergoes atrophy demonstrated by increased fat area (as % exocrine area) (0.05 ± 0.01 vs 1.6 ± 0.7% fat area of total exocrine pancreas, 3rd vs 9th decile, P < 0.05). Consequently, islet density increases with age (2.7 ± 0.4 vs 10.5 ± 3.3 islets/mm2, 3rd vs 9th decile, P < 0.05). Alpha-cell fractional area increases with advanced age (0.34 ± 0.05% vs 0.73 ± 0.26%, 3rd vs 9th decile, P < 0.05). However, alpha-cell mass remains constant at ~190 mg throughout the adult lifespan in lean, non-diabetic humans. Within islets, alpha-cell distribution between mantle and core is unchanged across deciles (1862 ± 220 vs 1945 ± 200 vs 1948 ± 139 alpha cells in islet mantle/mm2, 3rd vs 6th vs 9th decile, P = 0.93 and 1912 ± 442 vs 1449 ± 123 vs 1514 ± 168 alpha cells in islet core/mm2, 3rd vs 6th vs 9th decile, P = 0.47), suggesting that human islets retain their structural organization in the setting of age-related exocrine atrophy. CONCLUSIONS Consistent with our previous findings for beta-cell mass, alpha-cell mass remains constant in humans, even with advanced age. Pancreatic endocrine cells are much more robustly preserved than exocrine cells in aged humans, and islets maintain their structural integrity throughout life.
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Affiliation(s)
- Abu Saleh Md Moin
- Diabetes Research Center (DRC), Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), PO Box 34110, Doha, Qatar
| | - Megan Cory
- Larry Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Tatyana Gurlo
- Larry Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Yoshifumi Saisho
- Department of Internal Medicine, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Robert A Rizza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Peter C Butler
- Larry Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Alexandra E Butler
- Diabetes Research Center (DRC), Qatar Biomedical Research Institute (QBRI), Hamad Bin Khalifa University (HBKU), Qatar Foundation (QF), PO Box 34110, Doha, Qatar
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Nomoto H, Pei L, Montemurro C, Rosenberger M, Furterer A, Coppola G, Nadel B, Pellegrini M, Gurlo T, Butler PC, Tudzarova S. Activation of the HIF1α/PFKFB3 stress response pathway in beta cells in type 1 diabetes. Diabetologia 2020; 63:149-161. [PMID: 31720731 PMCID: PMC6945783 DOI: 10.1007/s00125-019-05030-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [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: 06/03/2019] [Accepted: 09/13/2019] [Indexed: 12/15/2022]
Abstract
AIMS/HYPOTHESIS The conserved hypoxia inducible factor 1 α (HIF1α) injury-response pro-survival pathway has recently been implicated in early beta cell dysfunction but slow beta cell loss in type 2 diabetes. We hypothesised that the unexplained prolonged prediabetes phase in type 1 diabetes may also be, in part, due to activation of the HIF1α signalling pathway. METHODS RNA sequencing (RNA-Seq) data from human islets with type 1 diabetes or after cytokine exposure in vitro was evaluated for activation of HIF1α targets. This was corroborated by immunostaining human pancreases from individuals with type 1 diabetes for 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), the key effector of HIF1α-mediated metabolic remodelling, and by western blotting of islets and INS-1 832/13 cells exposed to cytokines implicated in type 1 diabetes. RESULTS HIF1α signalling is activated (p = 4.5 × 10-9) in islets from individuals with type 1 diabetes, and in human islets exposed in vitro to cytokines implicated in type 1 diabetes (p = 1.1 × 10-14). Expression of PFKFB3 is increased fivefold (p < 0.01) in beta cells in type 1 diabetes and in human and rat islets exposed to cytokines that induced increased lactate production. HIF1α attenuates cytokine-induced cell death in beta cells. CONCLUSIONS/INTERPRETATION The conserved pro-survival HIF1α-mediated injury-response signalling is activated in beta cells in type 1 diabetes and likely contributes to the relatively slow rate of beta cell loss at the expense of early defective glucose-induced insulin secretion.
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Affiliation(s)
- Hiroshi Nomoto
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA
| | - Lina Pei
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA
| | - Chiara Montemurro
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA
| | - Madeline Rosenberger
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA
| | - Allison Furterer
- Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Giovanni Coppola
- Department of Neurology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Brian Nadel
- Molecular Cell and Developmental Biology, College of Life Sciences, University of California Los Angeles, Los Angeles, CA, USA
| | - Matteo Pellegrini
- Molecular Cell and Developmental Biology, College of Life Sciences, University of California Los Angeles, Los Angeles, CA, USA
| | - Tatyana Gurlo
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA.
| | - Slavica Tudzarova
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, University of California Los Angeles, 10833 Le Conte Avenue, 33-165 CHS, Los Angeles, CA, 90095-7073, USA
- Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
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Gurlo T, Kim S, Butler AE, Liu C, Pei L, Rosenberger M, Butler PC. Pregnancy in human IAPP transgenic mice recapitulates beta cell stress in type 2 diabetes. Diabetologia 2019; 62:1000-1010. [PMID: 30852627 PMCID: PMC6544020 DOI: 10.1007/s00125-019-4843-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 10/18/2018] [Accepted: 02/07/2019] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS Islet amyloid polypeptide (IAPP) misfolding and toxic oligomers contribute to beta cell loss and stress in type 2 diabetes. Pregnancy-related diabetes predicts subsequent risk for type 2 diabetes but little is known about the impact of pregnancy on beta cell mass, turnover and stress. Availability of human pancreas tissue in pregnancy is limited and most widely used mouse models of type 2 diabetes do not develop pregnancy-related diabetes, possibly because rodent IAPP is not prone to form toxic oligomers. We hypothesised that mice transgenic for human IAPP (hIAPP) are prone to pregnancy-related diabetes with beta cell responses reflective of those in type 2 diabetes. METHODS We evaluated the impact of a first and second pregnancy on glucose homeostasis, beta cell mass and turnover and markers of beta cell stress in hIAPP transgenic (hTG) mice. RESULTS Pregnancy induced both endoplasmic reticulum stress and oxidative stress and compromised autophagy in beta cells in hTG mice, which are characteristic of beta cells in type 2 diabetes. Beta cell stress persisted after pregnancy, resulting in subsequent diabetes before or during a second pregnancy. CONCLUSIONS/INTERPRETATION High expression of hIAPP in response to pregnancy recapitulates mechanisms contributing to beta cell stress in type 2 diabetes. We hypothesise that, in individuals prone to type 2 diabetes, pregnancy-induced increased expression of IAPP inflicts beta cell damage that persists and is compounded by subsequent additive stress such as further pregnancy. The hTG mouse model is a novel model for pregnancy-related diabetes.
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Affiliation(s)
- Tatyana Gurlo
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA
| | - Sarah Kim
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA
| | - Alexandra E Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA
| | - Chang Liu
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA
| | - Lina Pei
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA
| | - Madeline Rosenberger
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Avenue, 32-150 CHS, Los Angeles, CA, 90095-7073, USA.
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Butler AE, Kirakossian D, Gurlo T, Gao F, Coppola G, Butler PC. In the setting of β-cell stress, the pancreatic duct gland transcriptome shows characteristics of an activated regenerative response. Am J Physiol Gastrointest Liver Physiol 2018; 315:G848-G854. [PMID: 30095296 PMCID: PMC6293255 DOI: 10.1152/ajpgi.00177.2018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The pancreatic duct gland (PDG) compartment has been proposed as a potential stem cell niche based on its coiled tubular structure embedded in mesenchyme, its proliferation and expansion in response to pancreatic injury, and the fact that it contains endocrine and exocrine epithelial cells. Little is known of the molecular signature of the PDG compartment in either a quiescent state or the potentially activated state during β-cell stress characteristic of diabetes. To address this, we performed RNA sequencing on RNA obtained from PDGs of wild-type vs. prediabetic HIP rats, a model of type 2 diabetes. The transcriptome of the PDG compartment, compared with a library of 84 tissue types, placed PDGs midpoint between the exocrine and endocrine pancreas and closely related to seminiferous tubules, consistent with a role as a stem cell niche for the exocrine and endocrine pancreas. Standard differential expression analysis (permissive threshold P < 0.005) identified 245 genes differentially expressed in PDGs from HIP rats vs. WT rats, with overrepresentation of transcripts involved in acute inflammatory responses, regulation of cell proliferation, and tissue development, while pathway analysis pointed to enrichment of cell movement-related pathways. In conclusion, the transcriptome of the PDG compartment is consistent with a pancreatic stem cell niche that is activated by ongoing β-cell stress signals. The documented PDG transcriptome provides potential candidates to be exploited for lineage tracing studies of this as yet little investigated compartment. NEW & NOTEWORTHY The pancreatic duct gland (PDG) compartment has been proposed as a potential stem cell niche. Transcriptome analysis of the PDG gland placed it midpoint between exocrine and endocrine tissues with adaptation toward response to inflammation and increased cell movement in a model of type 2 diabetes with ongoing β-cell apoptosis. These findings support the proposal that PDGs may act as a pancreatic stem cell niche.
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Affiliation(s)
- Alexandra E. Butler
- 1Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - David Kirakossian
- 1Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Tatyana Gurlo
- 1Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Fuying Gao
- 2Department of Psychiatry, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Giovanni Coppola
- 2Department of Psychiatry, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Peter C. Butler
- 1Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
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Cory M, Moin ASM, Moran A, Rizza RA, Butler PC, Dhawan S, Butler AE. An Increase in Chromogranin A-Positive, Hormone-Negative Endocrine Cells in Pancreas in Cystic Fibrosis. J Endocr Soc 2018; 2:1058-1066. [PMID: 30202828 PMCID: PMC6125715 DOI: 10.1210/js.2018-00143] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/08/2018] [Indexed: 01/09/2023] Open
Abstract
We sought to establish whether an increase in chromogranin A-positive, hormone-negative (CPHN) endocrine cells occurs in the pancreas of patients with cystic fibrosis (CF), as potential evidence of neogenesis. Pancreata were obtained at autopsy from nondiabetic patients with CF (n = 12) and age-matched nondiabetic control subject (CS) individuals without CF (n = 12). In addition, pancreas from three diabetic patients with CF was obtained. Pancreas sections were stained for chromogranin A, insulin, and a cocktail of glucagon, somatostatin, pancreatic polypeptide, and ghrelin and evaluated for the frequency of CPHN cells. There was a higher frequency of CPHN cells in islets of the patients with CF compared with the CS group. Moreover, CPHN cells occurring as single cells or clusters scattered in the exocrine pancreas were also more frequent in patients with CF. The increased frequency of CPHN cells in pancreas of patients with CF may indicate an attempt at endocrine cell regeneration.
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Affiliation(s)
- Megan Cory
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Abu Saleh Md Moin
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Antoinette Moran
- Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
| | - Robert A Rizza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Sangeeta Dhawan
- Diabetes and Metabolism Research Institute, City of Hope, Duarte, California
| | - Alexandra E Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
- Life Sciences and Research Division, Anti-Doping Laboratory, Doha, Qatar
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15
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Moin ASM, Cory M, Choi J, Ong A, Dhawan S, Dry SM, Butler PC, Rizza RA, Butler AE. Increased Chromogranin A-Positive Hormone-Negative Cells in Chronic Pancreatitis. J Clin Endocrinol Metab 2018; 103:2126-2135. [PMID: 29659906 PMCID: PMC6456995 DOI: 10.1210/jc.2017-01562] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 03/30/2018] [Indexed: 01/09/2023]
Abstract
CONTEXT Chronic pancreatitis (CP) is characterized by inflammation, fibrosis, and a loss of pancreatic acinar cells, which can result in exocrine and eventually endocrine deficiency. Pancreatitis has been reported to induce formation of new endocrine cells (neogenesis) in mice. Our recent data have implicated chromogranin A-positive hormone-negative (CPHN) cells as potential evidence of neogenesis in humans. OBJECTIVE We sought to establish if CPHN cells were more abundant in CP in humans. DESIGN, SETTING, AND PARTICIPANTS We investigated the frequency and distribution of CPHN cells and the expression of the chemokine C-X-C motif ligand 10 (CXCL10) and its receptor chemokine C-X-C motif receptor 3 in pancreas of nondiabetic subjects with CP. RESULTS CPHN cell frequency in islets was increased sevenfold in CP [2.1% ± 0.67% vs 0.35% ± 0.09% CPHN cells in islets, CP vs nonpancreatitis (NP), P < 0.01], as were the CPHN cells found as scattered cells in the exocrine areas (17.4 ± 2.9 vs 4.2 ± 0.6, CP vs NP, P < 0.001). Polyhormonal endocrine cells were also increased in CP (2.7 ± 1.2 vs 0.1 ± 0.04, CP vs NP, % of polyhormonal cells of total endocrine cells, P < 0.01), as was expression of CXCL10 in α and β cells. CONCLUSION There is increased islet endogenous expression of the inflammation marker CXCL10 in islets in the setting of nondiabetic CP and an increase in polyhormonal (insulin-glucagon expressing) cells. The increase in CPHN cells in CP, often in a lobular distribution, may indicate foci of attempted endocrine cell regeneration.
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Affiliation(s)
- Abu Saleh Md Moin
- Diabetes and Metabolism Research Institute, City of Hope, Duarte, California
| | - Megan Cory
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Jennifer Choi
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Allison Ong
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Sangeeta Dhawan
- Diabetes and Metabolism Research Institute, City of Hope, Duarte, California
| | - Sarah M Dry
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, California
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Robert A Rizza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota
| | - Alexandra E Butler
- Anti Doping Laboratory Qatar, Doha, Qatar
- Correspondence and Reprint Requests: Alexandra E. Butler, MBBS, Anti-Doping Laboratory Qatar, PO Box 27775, Doha, Qatar. E-mail:
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Ruiz L, Gurlo T, Ravier MA, Wojtusciszyn A, Mathieu J, Brown MR, Broca C, Bertrand G, Butler PC, Matveyenko AV, Dalle S, Costes S. Proteasomal degradation of the histone acetyl transferase p300 contributes to beta-cell injury in a diabetes environment. Cell Death Dis 2018; 9:600. [PMID: 29789539 PMCID: PMC5964068 DOI: 10.1038/s41419-018-0603-0] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 03/09/2018] [Accepted: 04/17/2018] [Indexed: 12/25/2022]
Abstract
In type 2 diabetes, amyloid oligomers, chronic hyperglycemia, lipotoxicity, and pro-inflammatory cytokines are detrimental to beta-cells, causing apoptosis and impaired insulin secretion. The histone acetyl transferase p300, involved in remodeling of chromatin structure by epigenetic mechanisms, is a key ubiquitous activator of the transcriptional machinery. In this study, we report that loss of p300 acetyl transferase activity and expression leads to beta-cell apoptosis, and most importantly, that stress situations known to be associated with diabetes alter p300 levels and functional integrity. We found that proteasomal degradation is the mechanism subserving p300 loss in beta-cells exposed to hyperglycemia or pro-inflammatory cytokines. We also report that melatonin, a hormone produced in the pineal gland and known to play key roles in beta-cell health, preserves p300 levels altered by these toxic conditions. Collectively, these data imply an important role for p300 in the pathophysiology of diabetes.
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Affiliation(s)
- Lucie Ruiz
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Tatyana Gurlo
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Magalie A Ravier
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Anne Wojtusciszyn
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France.,Laboratory of Cell Therapy for Diabetes (LTCD), Institute for Regenerative Medicine and Biotherapy (IRMB), University Hospital of Montpellier, Montpellier, France.,Department of Endocrinology, Diabetes, and Nutrition, University Hospital of Montpellier, Montpellier, France
| | - Julia Mathieu
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Matthew R Brown
- Department of Physiology and Biomedical Engineering, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Christophe Broca
- Laboratory of Cell Therapy for Diabetes (LTCD), Institute for Regenerative Medicine and Biotherapy (IRMB), University Hospital of Montpellier, Montpellier, France
| | | | - Peter C Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA, USA
| | - Aleksey V Matveyenko
- Department of Physiology and Biomedical Engineering, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Stéphane Dalle
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Safia Costes
- IGF, CNRS, INSERM, University of Montpellier, Montpellier, France.
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Montemurro C, Vadrevu S, Gurlo T, Butler AE, Vongbunyong KE, Petcherski A, Shirihai OS, Satin LS, Braas D, Butler PC, Tudzarova S. Cell cycle-related metabolism and mitochondrial dynamics in a replication-competent pancreatic beta-cell line. Cell Cycle 2017; 16:2086-2099. [PMID: 28820316 DOI: 10.1080/15384101.2017.1361069] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Cell replication is a fundamental attribute of growth and repair in multicellular organisms. Pancreatic beta-cells in adults rarely enter cell cycle, hindering the capacity for regeneration in diabetes. Efforts to drive beta-cells into cell cycle have so far largely focused on regulatory molecules such as cyclins and cyclin-dependent kinases (CDKs). Investigations in cancer biology have uncovered that adaptive changes in metabolism, the mitochondrial network, and cellular Ca2+ are critical for permitting cells to progress through the cell cycle. Here, we investigated these parameters in the replication-competent beta-cell line INS 832/13. Cell cycle synchronization of this line permitted evaluation of cell metabolism, mitochondrial network, and cellular Ca2+ compartmentalization at key cell cycle stages. The mitochondrial network is interconnected and filamentous at G1/S but fragments during the S and G2/M phases, presumably to permit sorting to daughter cells. Pyruvate anaplerosis peaks at G1/S, consistent with generation of biomass for daughter cells, whereas mitochondrial Ca2+ and respiration increase during S and G2/M, consistent with increased energy requirements for DNA and lipid synthesis. This synchronization approach may be of value to investigators performing live cell imaging of Ca2+ or mitochondrial dynamics commonly undertaken in INS cell lines because without synchrony widely disparate data from cell to cell would be expected depending on position within cell cycle. Our findings also offer insight into why replicating beta-cells are relatively nonfunctional secreting insulin in response to glucose. They also provide guidance on metabolic requirements of beta-cells for the transition through the cell cycle that may complement the efforts currently restricted to manipulating cell cycle to drive beta-cells through cell cycle.
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Affiliation(s)
- Chiara Montemurro
- a Larry L. Hillblom Islet Research Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA
| | - Suryakiran Vadrevu
- b Department of Pharmacology and Brehm Diabetes Research Center , University of Michigan , Ann Arbor , MI , USA
| | - Tatyana Gurlo
- a Larry L. Hillblom Islet Research Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA
| | - Alexandra E Butler
- a Larry L. Hillblom Islet Research Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA
| | - Kenny E Vongbunyong
- a Larry L. Hillblom Islet Research Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA
| | - Anton Petcherski
- c Division of Endocrinology, Department of Medicine, David Geffen School of Medicine , University of California, Los Angeles , Los Angeles , CA , USA
| | - Orian S Shirihai
- c Division of Endocrinology, Department of Medicine, David Geffen School of Medicine , University of California, Los Angeles , Los Angeles , CA , USA
| | - Leslie S Satin
- b Department of Pharmacology and Brehm Diabetes Research Center , University of Michigan , Ann Arbor , MI , USA
| | - Daniel Braas
- d Department of Molecular and Medical Pharmacology, Crump Institute for Molecular Imaging , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA ; UCLA Metabolomics Center , University of California, Los Angeles , Los Angeles , CA , USA
| | - Peter C Butler
- a Larry L. Hillblom Islet Research Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA
| | - Slavica Tudzarova
- a Larry L. Hillblom Islet Research Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA.,e Jonsson Comprehensive Cancer Center , University of California, Los Angeles, David Geffen School of Medicine , Los Angeles , CA , USA
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18
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Schludi B, Moin ASM, Montemurro C, Gurlo T, Matveyenko AV, Kirakossian D, Dawson DW, Dry SM, Butler PC, Butler AE. Islet inflammation and ductal proliferation may be linked to increased pancreatitis risk in type 2 diabetes. JCI Insight 2017; 2:92282. [PMID: 28679961 DOI: 10.1172/jci.insight.92282] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 05/23/2017] [Indexed: 12/26/2022] Open
Abstract
Pancreatitis is more frequent in type 2 diabetes mellitus (T2DM), although the underlying cause is unknown. We tested the hypothesis that ongoing β cell stress and apoptosis in T2DM induces ductal tree proliferation, particularly the pancreatic duct gland (PDG) compartment, and thus potentially obstructs exocrine outflow, a well-established cause of pancreatitis. PDG replication was increased 2-fold in human pancreas from individuals with T2DM, and was associated with increased pancreatic intraepithelial neoplasia (PanIN), lesions associated with pancreatic inflammation and with the potential to obstruct pancreatic outflow. Increased PDG replication in the prediabetic human-IAPP-transgenic (HIP) rat model of T2DM was concordant with increased β cell stress but preceded metabolic derangement. Moreover, the most abundantly expressed chemokines released by the islets in response to β cell stress in T2DM, CXCL1, -4, and -10, induced proliferation in human pancreatic ductal epithelium. Also, the diabetes medications reported as potential modifiers for the risk of pancreatitis in T2DM modulated PDG proliferation accordingly. We conclude that chronic stimulation and proliferation of the PDG compartment in response to islet inflammation in T2DM is a potentially novel mechanism that serves as a link to the increased risk for pancreatitis in T2DM and may potentially be modified by currently available diabetes therapy.
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Affiliation(s)
| | | | | | | | | | | | - David W Dawson
- Department of Pathology and Laboratory Medicine.,Jonsson Comprehensive Cancer Center, UCLA, David Geffen School of Medicine, Los Angeles, California, USA
| | - Sarah M Dry
- Department of Pathology and Laboratory Medicine.,Jonsson Comprehensive Cancer Center, UCLA, David Geffen School of Medicine, Los Angeles, California, USA
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center.,Jonsson Comprehensive Cancer Center, UCLA, David Geffen School of Medicine, Los Angeles, California, USA
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Abstract
It has been proposed that the deficit in β-cell mass in type 1 diabetes (T1D) may be due, in part, to β-cell degranulation to chromogranin-positive hormone-negative (CPHN) cells. The frequency and distribution of pancreatic CPHN cells were investigated in 19 children with T1D compared with 14 nondiabetic (ND) children. We further evaluated these cells for replication and expression of endocrine lineage markers Nkx6.1 and Nkx2.2, and compared these frequencies with those previously reported in CPHN cells in adults with T1D. In contrast to adults’ cells, pancreatic CPHN cells were comparably abundant (percentage of endocrine cells ± standard error of the mean, 1.4 ± 0.2 vs 1.0 ± 0.2 in patients with T1D vs ND subjects, respectively; P = not significant) and comparably distributed in children with T1D vs ND donors. Replication of CPHN cells was detected but unchanged in children with T1D vs ND children, as was the percentage of CPHN cells expressing Nkx6.1 or NKx2.2. In children with T1D, the frequency of pancreatic CPHN cells was not increased, and this differed from adults with T1D.
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Affiliation(s)
- Abu Saleh Md Moin
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Megan Cory
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Allison Ong
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Jennifer Choi
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Sangeeta Dhawan
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Alexandra E Butler
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
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20
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Abstract
Aims/Hypothesis: We sought to establish whether the increased incidence of diabetes associated with Down syndrome was due to a congenital deficit in β cells. Methods: The pancreas was obtained at autopsy from nondiabetic subjects with Down syndrome (n = 29) and age-matched nondiabetic control subjects without Down syndrome (n = 28). The pancreas sections were evaluated for the fractional β-cell area. Results: No difference was found in the fractional β-cell area between the subjects with Down syndrome and the control subjects. Conclusions/Interpretations: The increased incidence and prevalence of diabetes in individuals with Down syndrome is not due to an underlying congenital deficiency of β cells.
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Affiliation(s)
- Alexandra E Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Wendy Sacks
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Robert A Rizza
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
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Moin ASM, Butler PC, Butler AE. Increased Proliferation of the Pancreatic Duct Gland Compartment in Type 1 Diabetes. J Clin Endocrinol Metab 2017; 102:200-209. [PMID: 27813705 PMCID: PMC5413103 DOI: 10.1210/jc.2016-3001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [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] [Received: 08/16/2016] [Accepted: 10/31/2016] [Indexed: 12/13/2022]
Abstract
CONTEXT Pancreatic duct glands (PDGs) have been proposed as a source of regeneration in response to exocrine pancreas injury, and thus may serve as an organ stem cell niche. There is evidence to suggest ongoing β-cell formation in longstanding type 1 diabetes (T1D), but the source is unknown. OBJECTIVE To investigate the PDG compartment of the pancreas in humans with T1D for evidence of an active regenerative signature (presence of progenitor cells and increased proliferation) and, in particular, as a potential source of β-cells. DESIGN, SETTING, AND PARTICIPANTS Pancreases from 46 brain dead organ donors (22 with T1D, 24 nondiabetic controls) were investigated for activation (increased proliferation) and markers of pancreatic exocrine and endocrine progenitors. RESULTS PDG cell replication was increased in T1D (6.3% ± 1.6% vs 0.6% ± 0.1%, P < 0.001, T1D vs nondiabetic), most prominently in association with pancreatic inflammation. There were increased progenitor-like cells in PDGs of T1D, but predominantly with an exocrine fate. CONCLUSION The PDG compartment is activated in T1D consistent with a response to ongoing inflammation, and via resulting ductal hyperplasia may contribute to local obstructive pancreatitis and eventual pancreatic atrophy characteristic of T1D. However, there is no evidence of effective endocrine cell formation from PDGs.
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Affiliation(s)
- Abu Saleh Md Moin
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
| | - Alexandra E Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095
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Gurlo T, Costes S, Hoang JD, Rivera JF, Butler AE, Butler PC. β Cell-specific increased expression of calpastatin prevents diabetes induced by islet amyloid polypeptide toxicity. JCI Insight 2016; 1:e89590. [PMID: 27812546 DOI: 10.1172/jci.insight.89590] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The islet in type 2 diabetes (T2D) shares many features of the brain in protein misfolding diseases. There is a deficit of β cells with islet amyloid derived from islet amyloid polypeptide (IAPP), a protein coexpressed with insulin. Small intracellular membrane-permeant oligomers, the most toxic form of IAPP, are more frequent in β cells of patients with T2D and rodents expressing human IAPP. β Cells in T2D, and affected cells in neurodegenerative diseases, share a comparable pattern of molecular pathology, including endoplasmic reticulum stress, mitochondrial dysfunction, attenuation of autophagy, and calpain hyperactivation. While this adverse functional cascade in response to toxic oligomers is well described, the sequence of events and how best to intervene is unknown. We hypothesized that calpain hyperactivation is a proximal event and tested this in vivo by β cell-specific suppression of calpain hyperactivation with calpastatin overexpression in human IAPP transgenic mice. β Cell-specific calpastatin overexpression was remarkably protective against β cell dysfunction and loss and diabetes onset. The critical autophagy/lysosomal pathway for β cell viability was protected with calpain suppression, consistent with findings in models of neurodegenerative diseases. We conclude that suppression of calpain hyperactivation is a potentially beneficial disease-modifying strategy for protein misfolding diseases, including T2D.
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Affiliation(s)
- Peter C Butler
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California-Los Angeles
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Md Moin AS, Dhawan S, Cory M, Butler PC, Rizza RA, Butler AE. Increased Frequency of Hormone Negative and Polyhormonal Endocrine Cells in Lean Individuals With Type 2 Diabetes. J Clin Endocrinol Metab 2016; 101:3628-3636. [PMID: 27472443 PMCID: PMC5052343 DOI: 10.1210/jc.2016-2496] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [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: 01/02/2023]
Abstract
CONTEXT It has been suggested that beta cell loss in type 2 diabetes (T2D) may be due to beta cell degranulation and/or altered cell identity. While shown to have a minor role in obese T2D, this has not been evaluated in lean T2D. OBJECTIVE To establish the contribution of altered beta cell identity in lean T2D and, using a rodent model of lean T2D, whether changes in beta cell identity precede hyperglycemia. DESIGN, SETTING, AND PARTICIPANTS We investigated the frequency of chromogranin A positive hormone negative (CPHN) and polyhormonal endocrine cells in pancreas from 10 lean nondiabetic and 10 lean T2D subjects and in pancreas from wild-type and human IAPP transgenic rats at the prediabetic and diabetic stages. RESULTS CPHN cells and polyhormonal-expressing cells were comparably increased in lean T2D and human IAPP transgenic rats, in the latter both before and at onset of diabetes. However, the extent of these cells could only account for approximately 2% of beta cell loss. CONCLUSION Degranulation and altered identity play at most a minor role in the beta cell deficit in lean T2D. Because the increase in CPHN and polyhormonal cells precede diabetes onset, these changes are likely a response to stress rather than hyperglycemia, and may reflect attempted regeneration.
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Affiliation(s)
- Abu Saleh Md Moin
- Larry L. Hillblom Islet Research Center (A.S.M.M., S.D., M.C., P.C.B., A.E.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California; Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Sangeeta Dhawan
- Larry L. Hillblom Islet Research Center (A.S.M.M., S.D., M.C., P.C.B., A.E.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California; Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Megan Cory
- Larry L. Hillblom Islet Research Center (A.S.M.M., S.D., M.C., P.C.B., A.E.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California; Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center (A.S.M.M., S.D., M.C., P.C.B., A.E.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California; Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Robert A Rizza
- Larry L. Hillblom Islet Research Center (A.S.M.M., S.D., M.C., P.C.B., A.E.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California; Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, MN 55905
| | - Alexandra E Butler
- Larry L. Hillblom Islet Research Center (A.S.M.M., S.D., M.C., P.C.B., A.E.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California; Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, MN 55905
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25
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Abstract
CONTEXT AND OBJECTIVE Type 1 diabetes (T1D) is characterized by a β-cell deficit due to autoimmune inflammatory-mediated β-cell destruction. It has been proposed the deficit in β-cell mass in T1D may be in part due to β-cell degranulation to chromogranin-positive, hormone-negative (CPHN) cells. DESIGN, SETTING, AND PARTICIPANTS We investigated the frequency and distribution of CPHN cells in the pancreas of 15 individuals with T1D, 17 autoantibody-positive nondiabetic individuals, and 17 nondiabetic controls. RESULTS CPHN cells were present at a low frequency in the pancreas from nondiabetic and autoantibody-positive, brain-dead organ donors but are more frequently found in the pancreas from donors with T1D (islets: 1.11% ± 0.20% vs 0.26% ± 0.06 vs 0.27% ± 0.10% of islet endocrine cells, T1D vs autoantibody positive [AA+] vs nondiabetic [ND]; T1D vs AA+, and ND, P < .001). CPHN cells are most commonly found in the single cells and small clusters of endocrine cells rather than within established islets (clusters: 18.99% ± 2.09% vs 9.67% ± 1.49% vs 7.42% ± 1.26% of clustered endocrine cells, T1D vs AA+ vs ND; T1D vs AA+ and ND, P < .0001), mimicking the distribution present in neonatal pancreas. CONCLUSIONS From these observations, we conclude that CPHN cells are more frequent in T1D and, as in type 2 diabetes, are distributed in a pattern comparable with the neonatal pancreas, implying a possible attempted regeneration. In contrast to rodents, CPHN cells are insufficient to account for loss of β-cell mass in T1D.
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Affiliation(s)
- Abu Saleh Md Moin
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-7073
| | - Sangeeta Dhawan
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-7073
| | - Christine Shieh
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-7073
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-7073
| | - Megan Cory
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-7073
| | - Alexandra E Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-7073
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26
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Abstract
Immunohistochemistry (IHC) and immunofluorescence (IF) staining techniques are important diagnostic tools of anatomic pathology in the clinical setting and widely used analytical tools in research laboratories. In diabetes research, they are routinely used for the assessment of beta- and alpha-cell mass, for assessment of endocrine cell distribution within the pancreas, for evaluation of islet composition and islet morphology. Here, we present the evaluation of IHC techniques for the detection of alpha-cells in human pancreatic tissue. We compared the Horse Radish Peroxidase (HRP)-based method utilizing DAB Peroxidase Substrate to the Alkaline Phosphatase (AP)-based method utilizing Vector Red substrate. We conclude that HRP-DAB staining is a robust and reliable method for detection of alpha-cells using either rabbit polyclonal or mouse monoclonal anti-glucagon antibodies. However, AP-Vector Red staining should be used with caution, because it is affected by the dehydration with ethanol and toluene preceding the mounting of slides with Permount mounting medium. When AP-Vector Red is a preferable method for alpha-cell labeling, slides should be mounted using aqueous mounting medium or, alternatively, they could be air-dried before permanent mounting.
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Affiliation(s)
- Tatyana Gurlo
- Larry L. Hillblom, Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Peter C Butler
- Larry L. Hillblom, Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA; Jonsson Comprehensive Cancer Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles CA, USA
| | - Alexandra E Butler
- Larry L. Hillblom, Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
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27
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Butler AE, Matveyenko AV, Kirakossian D, Park J, Gurlo T, Butler PC. Recovery of high-quality RNA from laser capture microdissected human and rodent pancreas. J Histotechnol 2016; 39:59-65. [PMID: 27231405 DOI: 10.1080/01478885.2015.1106073] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Laser capture microdissection (LCM) is a powerful method to isolate specific populations of cells for subsequent analysis such as gene expression profiling, for example, microarrays or ribonucleic (RNA)-Seq. This technique has been applied to frozen as well as formalin-fixed, paraffin-embedded (FFPE) specimens with variable outcomes regarding quality and quantity of extracted RNA. The goal of the study was to develop the methods to isolate high-quality RNA from islets of Langerhans and pancreatic duct glands (PDG) isolated by LCM. We report an optimized protocol for frozen sections to minimize RNA degradation and maximize recovery of expected transcripts from the samples using quantitative real-time polymerase chain reaction (RT-PCR) by adding RNase inhibitors at multiple steps during the experiment. This technique reproducibly delivered intact RNA (RIN values 6-7). Using quantitative RT-PCR, the expected profiles of insulin, glucagon, mucin6 (Muc6), and cytokeratin-19 (CK-19) mRNA in PDGs and pancreatic islets were detected. The described experimental protocol for frozen pancreas tissue might also be useful for other tissues with moderate to high levels of intrinsic ribonuclease (RNase) activity.
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Affiliation(s)
- Alexandra E Butler
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Aleksey V Matveyenko
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA ; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - David Kirakossian
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Johanna Park
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Tatyana Gurlo
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA ; Jonsson Comprehensive Cancer Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
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Gurlo T, Rivera JF, Butler AE, Cory M, Hoang J, Costes S, Butler PC. CHOP Contributes to, But Is Not the Only Mediator of, IAPP Induced β-Cell Apoptosis. Mol Endocrinol 2016; 30:446-54. [PMID: 26900721 DOI: 10.1210/me.2015-1255] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The islet in type 2 diabetes is characterized by β-cell loss, increased β-cell apoptosis, and islet amyloid derived from islet amyloid polypeptide (IAPP). When protein misfolding protective mechanisms are overcome, human IAPP (h-IAPP) forms membrane permeant toxic oligomers that induce β-cell dysfunction and apoptosis. In humans with type 2 diabetes (T2D) and mice transgenic for h-IAPP, endoplasmic reticulum (ER) stress has been inferred from nuclear translocation of CCAAT/enhancer-binding protein homologous protein (CHOP), an established mediator of ER stress. To establish whether h-IAPP toxicity is mediated by ER stress, we evaluated diabetes onset and β-cell mass in h-IAPP transgenic (h-TG) mice with and without deletion of CHOP in comparison with wild-type controls. Diabetes was delayed in h-TG CHOP(-/-) mice, with relatively preserved β-cell mass and decreased β-cell apoptosis. Deletion of CHOP attenuates dysfunction of the autophagy/lysosomal pathway in β-cells of h-TG mice, uncovering a role for CHOP in mediating h-IAPP-induced dysfunction of autophagy. As deletion of CHOP delayed but did not prevent h-IAPP-induced β-cell loss and diabetes, we examined CHOP-independent stress pathways. JNK, a target of the IRE-1pTRAF2 complex, and the Bcl-2 family proapoptotic mediator BIM, a target of ATF4, were comparably activated by h-IAPP expression in the presence and absence of CHOP. Therefore, although these studies affirm that CHOP is a mediator of h-IAPP-induced ER stress, it is not the only one. Therefore, suppression of CHOP alone is unlikely to be a durable therapeutic strategy to protect against h-IAPP toxicity because multiple stress pathways are activated.
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Affiliation(s)
- T Gurlo
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
| | - J F Rivera
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
| | - A E Butler
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
| | - M Cory
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
| | - J Hoang
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
| | - S Costes
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, California 90095-7073
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29
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Butler AE, Dhawan S, Hoang J, Cory M, Zeng K, Fritsch H, Meier JJ, Rizza RA, Butler PC. β-Cell Deficit in Obese Type 2 Diabetes, a Minor Role of β-Cell Dedifferentiation and Degranulation. J Clin Endocrinol Metab 2016; 101:523-32. [PMID: 26700560 PMCID: PMC4880126 DOI: 10.1210/jc.2015-3566] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [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: 12/20/2022]
Abstract
CONTEXT Type 2 diabetes is characterized by a β-cell deficit and a progressive defect in β-cell function. It has been proposed that the deficit in β-cells may be due to β-cell degranulation and transdifferentiation to other endocrine cell types. OBJECTIVE The objective of the study was to establish the potential impact of β-cell dedifferentiation and transdifferentiation on β-cell deficit in type 2 diabetes and to consider the alternative that cells with an incomplete identity may be newly forming rather than dedifferentiated. DESIGN, SETTING, AND PARTICIPANTS Pancreata obtained at autopsy were evaluated from 14 nondiabetic and 13 type 2 diabetic individuals, from four fetal cases, and from 10 neonatal cases. RESULTS Whereas there was a slight increase in islet endocrine cells expressing no hormone in type 2 diabetes (0.11 ± 0.03 cells/islet vs 0.03 ± 0.01 cells/islet, P < .01), the impact on the β-cell deficit would be minimal. Furthermore, we established that the deficit in β-cells per islet cannot be accounted for by an increase in other endocrine cell types. The distribution of hormone negative endocrine cells in type 2 diabetes (most abundant in cells scattered in the exocrine pancreas) mirrors that in developing (embryo and neonatal) pancreas, implying that these may represent newly forming cells. CONCLUSIONS Therefore, although we concur that in type 2 diabetes there are endocrine cells with altered cell identity, this process does not account for the deficit in β-cells in type 2 diabetes but may reflect, in part, attempted β-cell regeneration.
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Affiliation(s)
- Alexandra E Butler
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Sangeeta Dhawan
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Jonathan Hoang
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Megan Cory
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Kylie Zeng
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Helga Fritsch
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Juris J Meier
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Robert A Rizza
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center (A.E.B., S.D., J.H., M.C., K.Z., P.C.B.), David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90095-7073; Institute of Pathology (H.F.), Division of Clinical and Functional Anatomy, Medical University of Innsbruck, A-6020 Innsbruck, Austria; St Josef Hospital of the Ruhr-University Bochum (J.J.M.), 44791 Bochum, Germany; and Division of Endocrinology, Diabetes, Metabolism, and Nutrition (R.A.R.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
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30
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Kegulian NC, Sankhagowit S, Apostolidou M, Jayasinghe SA, Malmstadt N, Butler PC, Langen R. Membrane Curvature-sensing and Curvature-inducing Activity of Islet Amyloid Polypeptide and Its Implications for Membrane Disruption. J Biol Chem 2015; 290:25782-93. [PMID: 26283787 DOI: 10.1074/jbc.m115.659797] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Indexed: 11/06/2022] Open
Abstract
Islet amyloid polypeptide (IAPP) is a 37-amino acid amyloid protein intimately associated with pancreatic islet β-cell dysfunction and death in type II diabetes. In this study, we combine spectroscopic methods and microscopy to investigate α-helical IAPP-membrane interactions. Using light scattering and fluorescence microscopy, we observe that larger vesicles become smaller upon treatment with human or rat IAPP. Electron microscopy shows the formation of various highly curved structures such as tubules or smaller vesicles in a membrane-remodeling process, and spectrofluorometric detection of vesicle leakage shows disruption of membrane integrity. This effect is stronger for human IAPP than for the less toxic rat IAPP. From CD spectra in the presence of different-sized vesicles, we also uncover the membrane curvature-sensing ability of IAPP and find that it transitions from inducing to sensing membrane curvature when lipid negative charge is decreased. Our in vivo EM images of immunogold-labeled rat IAPP and human IAPP show both forms to localize to mitochondrial cristae, which contain not only locally curved membranes but also phosphatidylethanolamine and cardiolipin, lipids with high spontaneous negative curvature. Disruption of membrane integrity by induction of membrane curvature could apply more broadly to other amyloid proteins and be responsible for membrane damage observed in other amyloid diseases as well.
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Affiliation(s)
- Natalie C Kegulian
- From the Department of Biochemistry and Molecular Biology, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033
| | - Shalene Sankhagowit
- the Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, and
| | - Melania Apostolidou
- From the Department of Biochemistry and Molecular Biology, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033
| | - Sajith A Jayasinghe
- From the Department of Biochemistry and Molecular Biology, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033
| | - Noah Malmstadt
- the Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089, and
| | - Peter C Butler
- the Larry Hillblom Islet Research Center, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - Ralf Langen
- From the Department of Biochemistry and Molecular Biology, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, California 90033,
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31
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Mukherjee A, Morales-Scheihing D, Butler PC, Soto C. Type 2 diabetes as a protein misfolding disease. Trends Mol Med 2015; 21:439-49. [PMID: 25998900 DOI: 10.1016/j.molmed.2015.04.005] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 04/16/2015] [Accepted: 04/22/2015] [Indexed: 12/12/2022]
Abstract
Type 2 diabetes (T2D) is a highly prevalent and chronic metabolic disorder. Recent evidence suggests that formation of toxic aggregates of the islet amyloid polypeptide (IAPP) might contribute to β-cell dysfunction and disease. However, the mechanism of protein aggregation and associated toxicity remains unclear. Misfolding, aggregation, and accumulation of diverse proteins in various organs is the hallmark of the group of protein misfolding disorders (PMDs), including highly prevalent illnesses affecting the central nervous system (CNS) such as Alzheimer's disease (AD) and Parkinson's disease (PD). In this review we discuss the current understanding of the mechanisms implicated in the formation of protein aggregates in the endocrine pancreas and associated toxicity in the light of the long-standing knowledge from neurodegenerative disorders associated with protein misfolding.
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Affiliation(s)
- Abhisek Mukherjee
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA
| | - Diego Morales-Scheihing
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA; Universidad de los Andes, Facultad de Medicina, Av. San Carlos de Apoquindo 2200, Las Condes, Santiago, Chile
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California at Los Angeles, Los Angeles, CA, USA
| | - Claudio Soto
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA.
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32
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Costes S, Gurlo T, Rivera JF, Butler PC. UCHL1 deficiency exacerbates human islet amyloid polypeptide toxicity in β-cells: evidence of interplay between the ubiquitin/proteasome system and autophagy. Autophagy 2015; 10:1004-14. [PMID: 24879150 DOI: 10.4161/auto.28478] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The islet in type 2 diabetes mellitus (T2DM) is characterized by a deficit in β-cells and increased β-cell apoptosis attributable at least in part to intracellular toxic oligomers of IAPP (islet amyloid polypeptide). β-cells of individuals with T2DM are also characterized by accumulation of polyubiquitinated proteins and deficiency in the deubiquitinating enzyme UCHL1 (ubiquitin carboxyl-terminal esterase L1 [ubiquitin thiolesterase]), accounting for a dysfunctional ubiquitin/proteasome system. In the present study, we used mouse genetics to elucidate in vivo whether a partial deficit in UCHL1 enhances the vulnerability of β-cells to human-IAPP (hIAPP) toxicity, and thus accelerates diabetes onset. We further investigated whether a genetically induced deficit in UCHL1 function in β-cells exacerbates hIAPP-induced alteration of the autophagy pathway in vivo. We report that a deficit in UCHL1 accelerated the onset of diabetes in hIAPP transgenic mice, due to a decrease in β-cell mass caused by increased β-cell apoptosis. We report that UCHL1 dysfunction aggravated the hIAPP-induced defect in the autophagy/lysosomal pathway, illustrated by the marked accumulation of autophagosomes and cytoplasmic inclusions positive for SQSTM1/p62 and polyubiquitinated proteins with lysine 63-specific ubiquitin chains. Collectively, this study shows that defective UCHL1 function may be an early contributor to vulnerability of pancreatic β-cells for protein misfolding and proteotoxicity, hallmark defects in islets of T2DM. Also, given that deficiency in UCHL1 exacerbated the defective autophagy/lysosomal degradation characteristic of hIAPP proteotoxicity, we demonstrate a previously unrecognized role of UCHL1 in the function of the autophagy/lysosomal pathway in β-cells.
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Affiliation(s)
- Safia Costes
- Larry L. Hillblom Islet Research Center; David Geffen School of Medicine; University of California, Los Angeles; Los Angeles, CA USA
| | - Tatyana Gurlo
- Larry L. Hillblom Islet Research Center; David Geffen School of Medicine; University of California, Los Angeles; Los Angeles, CA USA
| | - Jacqueline F Rivera
- Larry L. Hillblom Islet Research Center; David Geffen School of Medicine; University of California, Los Angeles; Los Angeles, CA USA
| | - Peter C Butler
- Larry L. Hillblom Islet Research Center; David Geffen School of Medicine; University of California, Los Angeles; Los Angeles, CA USA
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33
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Abstract
The insulin-degrading enzyme (IDE) has been identified as a type 2 diabetes and Alzheimer's disease susceptibility gene, though its physiological function remains unclear. Maianti et al. (2014) now propose that an IDE inhibitor may be a promising therapeutic strategy for type 2 diabetes.
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Affiliation(s)
- Safia Costes
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Peter C Butler
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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34
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Rivera JF, Costes S, Gurlo T, Glabe CG, Butler PC. Autophagy defends pancreatic β cells from human islet amyloid polypeptide-induced toxicity. J Clin Invest 2014; 124:3489-500. [PMID: 25036708 DOI: 10.1172/jci71981] [Citation(s) in RCA: 174] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 05/23/2014] [Indexed: 12/21/2022] Open
Abstract
Type 2 diabetes (T2D) is characterized by a deficiency in β cell mass, increased β cell apoptosis, and extracellular accumulation of islet amyloid derived from islet amyloid polypeptide (IAPP), which β cells coexpress with insulin. IAPP expression is increased in the context of insulin resistance, the major risk factor for developing T2D. Human IAPP is potentially toxic, especially as membrane-permeant oligomers, which have been observed to accumulate within β cells of patients with T2D and rodents expressing human IAPP. Here, we determined that β cell IAPP content is regulated by autophagy through p62-dependent lysosomal degradation. Induction of high levels of human IAPP in mouse β cells resulted in accumulation of this amyloidogenic protein as relatively inert fibrils within cytosolic p62-positive inclusions, which temporarily averts formation of toxic oligomers. Mice hemizygous for transgenic expression of human IAPP did not develop diabetes; however, loss of β cell-specific autophagy in these animals induced diabetes, which was attributable to accumulation of toxic human IAPP oligomers and loss of β cell mass. In human IAPP-expressing mice that lack β cell autophagy, increased oxidative damage and loss of an antioxidant-protective pathway appeared to contribute to increased β cell apoptosis. These findings indicate that autophagy/lysosomal degradation defends β cells against proteotoxicity induced by oligomerization-prone human IAPP.
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Butler AE, Campbell-Thompson M, Gurlo T, Dawson DW, Atkinson M, Butler PC. Response to comments on: Butler et al. Marked expansion of exocrine and endocrine pancreas with incretin therapy in humans with increased exocrine pancreas dysplasia and the potential for glucagon-producing neuroendocrine tumors. Diabetes 2013;62:2595-2604. Diabetes 2013; 62:e19-22. [PMID: 24065800 PMCID: PMC3781463 DOI: 10.2337/db13-0996] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Alexandra E. Butler
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Martha Campbell-Thompson
- Departments of Pathology and Pediatrics, College of Medicine, University of Florida, Gainesville, Florida
| | - Tatyana Gurlo
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - David W. Dawson
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
| | - Mark Atkinson
- Departments of Pathology and Pediatrics, College of Medicine, University of Florida, Gainesville, Florida
| | - Peter C. Butler
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California
- Corresponding author: Peter C. Butler,
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Butler AE, Campbell-Thompson M, Gurlo T, Dawson DW, Atkinson M, Butler PC. Marked expansion of exocrine and endocrine pancreas with incretin therapy in humans with increased exocrine pancreas dysplasia and the potential for glucagon-producing neuroendocrine tumors. Diabetes 2013; 62:2595-604. [PMID: 23524641 PMCID: PMC3712065 DOI: 10.2337/db12-1686] [Citation(s) in RCA: 326] [Impact Index Per Article: 29.6] [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] [Indexed: 12/17/2022]
Abstract
Controversy exists regarding the potential regenerative influences of incretin therapy on pancreatic β-cells versus possible adverse pancreatic proliferative effects. Examination of pancreata from age-matched organ donors with type 2 diabetes mellitus (DM) treated by incretin therapy (n = 8) or other therapy (n = 12) and nondiabetic control subjects (n = 14) reveals an ∼40% increased pancreatic mass in DM treated with incretin therapy, with both increased exocrine cell proliferation (P < 0.0001) and dysplasia (increased pancreatic intraepithelial neoplasia, P < 0.01). Pancreata in DM treated with incretin therapy were notable for α-cell hyperplasia and glucagon-expressing microadenomas (3 of 8) and a neuroendocrine tumor. β-Cell mass was reduced by ∼60% in those with DM, yet a sixfold increase was observed in incretin-treated subjects, although DM persisted. Endocrine cells costaining for insulin and glucagon were increased in DM compared with non-DM control subjects (P < 0.05) and markedly further increased by incretin therapy (P < 0.05). In conclusion, incretin therapy in humans resulted in a marked expansion of the exocrine and endocrine pancreatic compartments, the former being accompanied by increased proliferation and dysplasia and the latter by α-cell hyperplasia with the potential for evolution into neuroendocrine tumors.
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Affiliation(s)
- Alexandra E Butler
- Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
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Abstract
There is no question that incretin-based glucose-lowering medications have proven to be effective glucose-lowering agents. Glucagon-like peptide 1 (GLP-1) receptor agonists demonstrate an efficacy comparable to insulin treatment and appear to do so with significant effects to promote weight loss with minimal hypoglycemia. In addition, there are significant data with dipeptidyl peptidase 4 (DPP-4) inhibitors showing efficacy comparable to sulfonylureas but with weight neutral effects and reduced risk for hypoglycemia. However, over the recent past there have been concerns reported regarding the long-term consequences of using such therapies, and the issues raised are in regard to the potential of both classes to promote acute pancreatitis, to initiate histological changes suggesting chronic pancreatitis including associated preneoplastic lesions, and potentially, in the long run, pancreatic cancer. Other issues relate to a potential risk for the increase in thyroid cancer. There are clearly conflicting data that have been presented in preclinical studies and in epidemiologic studies. To provide an understanding of both sides of the argument, we provide a discussion of this topic as part of this two-part point-counterpoint narrative. In the point narrative below, Dr. Butler and colleagues provide their opinion and review of the data to date and that we need to reconsider the use of incretin-based therapies because of the growing concern of potential risk and based on a clearer understanding of the mechanism of action. In the counterpoint narrative following the contribution by Dr. Butler and colleagues, Dr. Nauck provides a defense of incretin-based therapies and that the benefits clearly outweigh any concern of risk.
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Affiliation(s)
- Peter C Butler
- Larry L. Hillblom Islet Research Center, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California, USA
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Saisho Y, Butler AE, Manesso E, Butler PC. Response to Comment on: Saisho et al. β-cell mass and turnover in humans: effects of obesity and aging. Diabetes Care 2013;36:111-117. Diabetes Care 2013; 36:e112. [PMID: 23801813 PMCID: PMC3687307 DOI: 10.2337/dc13-0486] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Yoshifumi Saisho
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California
- Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Alexandra E. Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California
| | - Erica Manesso
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California
- Department of Astronomy and Theoretical Physics, Lund University, Lund, Sweden
| | - Peter C. Butler
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, California
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Affiliation(s)
- Belinda Gier
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA 90095, USA
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Abstract
The islet in type 2 diabetes (T2DM) is characterized by a deficit in β-cells, increased β-cell apoptosis, and extracellular amyloid deposits derived from islet amyloid polypeptide (IAPP). In the absence of longitudinal studies, it is unknown if the low β-cell mass in T2DM precedes diabetes onset (is a risk factor for diabetes) or develops as a consequence of the disease process. Although insulin resistance is a risk factor for T2DM, most individuals who are insulin resistant do not develop diabetes. By inference, an increased β-cell workload results in T2DM in some but not all individuals. We propose that the extent of the β-cell mass that develops during childhood may underlie subsequent successful or failed adaptation to insulin resistance in later life. We propose that a low innate β-cell mass in the face of subsequent insulin resistance may expose β-cells to a burden of insulin and IAPP biosynthetic demand that exceeds the cellular capacity for protein folding and trafficking. If this threshold is crossed, intracellular toxic IAPP membrane permeant oligomers (cylindrins) may form, compromising β-cell function and inducing β-cell apoptosis.
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Affiliation(s)
- Safia Costes
- Division of Endocrinology, Larry L. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
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Abstract
OBJECTIVE We sought to establish β-cell mass, β-cell apoptosis, and β-cell replication in humans in response to obesity and advanced age. RESEARCH DESIGN AND METHODS We examined human autopsy pancreas from 167 nondiabetic individuals 20-102 years of age. The effect of obesity on β-cell mass was examined in 53 lean and 61 obese subjects, and the effect of aging was examined in 106 lean subjects. RESULTS β-Cell mass is increased by ~50% with obesity (from 0.8 to 1.2 g). With advanced aging, the exocrine pancreas undergoes atrophy but β-cell mass is remarkably preserved. There is minimal β-cell replication or apoptosis in lean humans throughout life with no detectable changes with obesity or advanced age. CONCLUSIONS β-Cell mass in human obesity increases by ~50% by an increase in β-cell number, the source of which is unknown. β-Cell mass is well preserved in humans with advanced aging.
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Affiliation(s)
- Yoshifumi Saisho
- Larry L. Hillblom Islet Research Center, University of California, Los Angeles, David Geffen School of Medicine, Los Angeles, CA, USA
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Matveyenko AV, Liuwantara D, Gurlo T, Kirakossian D, Dalla Man C, Cobelli C, White MF, Copps KD, Volpi E, Fujita S, Butler PC. Pulsatile portal vein insulin delivery enhances hepatic insulin action and signaling. Diabetes 2012; 61:2269-79. [PMID: 22688333 PMCID: PMC3425431 DOI: 10.2337/db11-1462] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [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] [Indexed: 11/24/2022]
Abstract
Insulin is secreted as discrete insulin secretory bursts at ~5-min intervals into the hepatic portal vein, these pulses being attenuated early in the development of type 1 and type 2 diabetes mellitus (T2DM). Intraportal insulin infusions (pulsatile, constant, or reproducing that in T2DM) indicated that the pattern of pulsatile insulin secretion delivered via the portal vein is important for hepatic insulin action and, therefore, presumably for hepatic insulin signaling. To test this, we examined hepatic insulin signaling in rat livers exposed to the same three patterns of portal vein insulin delivery by use of sequential liver biopsies in anesthetized rats. Intraportal delivery of insulin in a constant versus pulsatile pattern led to delayed and impaired activation of hepatic insulin receptor substrate (IRS)-1 and IRS-2 signaling, impaired activation of downstream insulin signaling effector molecules AKT and Foxo1, and decreased expression of glucokinase (Gck). We further established that hepatic Gck expression is decreased in the HIP rat model of T2DM, a defect that correlated with a progressive defect of pulsatile insulin secretion. We conclude that the physiological pulsatile pattern of insulin delivery is important in hepatic insulin signaling and glycemic control. Hepatic insulin resistance in diabetes is likely in part due to impaired pulsatile insulin secretion.
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Affiliation(s)
- Aleksey V. Matveyenko
- Larry Hillblom Islet Research Center, Division of Endocrinology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - David Liuwantara
- Larry Hillblom Islet Research Center, Division of Endocrinology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Tatyana Gurlo
- Larry Hillblom Islet Research Center, Division of Endocrinology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - David Kirakossian
- Larry Hillblom Islet Research Center, Division of Endocrinology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
| | - Chiara Dalla Man
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Morris F. White
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital, Boston, Massachusetts
| | - Kyle D. Copps
- Howard Hughes Medical Institute, Division of Endocrinology, Children’s Hospital, Boston, Massachusetts
| | - Elena Volpi
- Department of Internal Medicine and Sealy Center on Aging, University of Texas Medical Branch, Galveston, Texas
| | - Satoshi Fujita
- Department of Internal Medicine and Sealy Center on Aging, University of Texas Medical Branch, Galveston, Texas
| | - Peter C. Butler
- Larry Hillblom Islet Research Center, Division of Endocrinology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California
- Corresponding author: Peter C. Butler,
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Gier B, Matveyenko AV, Kirakossian D, Dawson D, Dry SM, Butler PC. Chronic GLP-1 receptor activation by exendin-4 induces expansion of pancreatic duct glands in rats and accelerates formation of dysplastic lesions and chronic pancreatitis in the Kras(G12D) mouse model. Diabetes 2012; 61:1250-62. [PMID: 22266668 PMCID: PMC3331736 DOI: 10.2337/db11-1109] [Citation(s) in RCA: 178] [Impact Index Per Article: 14.8] [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] [Indexed: 12/12/2022]
Abstract
Pancreatic duct glands (PDGs) have been hypothesized to give rise to pancreatic intraepithelial neoplasia (PanIN). Treatment with the glucagon-like peptide (GLP)-1 analog, exendin-4, for 12 weeks induced the expansion of PDGs with mucinous metaplasia and columnar cell atypia resembling low-grade PanIN in rats. In the pancreata of Pdx1-Cre; LSL-Kras(G12D) mice, exendin-4 led to acceleration of the disruption of exocrine architecture and chronic pancreatitis with mucinous metaplasia and increased formation of murine PanIN lesions. PDGs and PanIN lesions in rodent and human pancreata express the GLP-1 receptor. Exendin-4 induced proproliferative signaling pathways in human pancreatic duct cells, cAMP-protein kinase A and mitogen-activated protein kinase phosphorylation of cAMP-responsive element-binding protein, and increased cyclin D1 expression. These GLP-1 effects were more pronounced in the presence of an activating mutation of Kras and were inhibited by metformin. These data reveal that GLP-1 mimetic therapy may induce focal proliferation in the exocrine pancreas and, in the context of exocrine dysplasia, may accelerate formation of neoplastic PanIN lesions and exacerbate chronic pancreatitis.
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Affiliation(s)
- Belinda Gier
- Larry L. Hillblom Islet Research Center, University of California Los Angeles (UCLA), David Geffen School of Medicine, Los Angeles, California, USA.
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Abstract
BACKGROUND Glucagon like peptide-1 (GLP-1) mimetic therapy induces medullary thyroid neoplasia in rodents. We sought to establish whether C cells in human medullary thyroid carcinoma, C cell hyperplasia, and normal human thyroid express the GLP-1 receptor. METHODS Thyroid tissue samples with medullary thyroid carcinoma (n = 12), C cell hyperplasia (n = 9), papillary thyroid carcinoma (n = 17), and normal human thyroid (n = 15) were evaluated by immunofluorescence for expression of calcitonin and GLP-1 receptors. RESULTS Coincident immunoreactivity for calcitonin and GLP-1 receptor was consistently observed in both medullary thyroid carcinoma and C cell hyperplasia. GLP-1 receptor immunoreactivity was also detected in 18% of papillary thyroid carcinoma (three of 17 cases). Within normal human thyroid tissue, GLP-1 receptor immunoreactivity was found in five of 15 of the examined cases in about 35% of the total C cells assessed. CONCLUSIONS In humans, neoplastic and hyperplastic lesions of thyroid C cells express the GLP-1 receptor. GLP-1 receptor expression is detected in 18% papillary thyroid carcinomas and in C cells in 33% of control thyroid lobes. The consequence of long-term pharmacologically increased GLP-1 signaling on these GLP-1 receptor-expressing cells in the thyroid gland in humans remains unknown, but appropriately powered prospective studies to exclude an increase in medullary or papillary carcinomas of the thyroid are warranted.
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Affiliation(s)
- Belinda Gier
- Larry L. Hillblom Islet Research Center, David Geffen School of Medicine at the University of California, Los Angeles, 10833 Le Conte Avenue 72-228 CHS, Los Angeles, California 90095-6904, USA
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Butler PC. Farewell statement from Dr. Peter Butler as outgoing editor in chief of diabetes. Diabetes 2011; 60:3099. [PMID: 22110090 PMCID: PMC3219941 DOI: 10.2337/db11-1127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Sdek P, Zhao P, Wang Y, Huang CJ, Ko CY, Butler PC, Weiss JN, Maclellan WR. Rb and p130 control cell cycle gene silencing to maintain the postmitotic phenotype in cardiac myocytes. ACTA ACUST UNITED AC 2011; 194:407-23. [PMID: 21825075 PMCID: PMC3153646 DOI: 10.1083/jcb.201012049] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The mammalian heart loses its regenerative potential soon after birth. Adult cardiac myocytes (ACMs) permanently exit the cell cycle, and E2F-dependent genes are stably silenced, although the underlying mechanism is unclear. Heterochromatin, which silences genes in many biological contexts, accumulates with cardiac differentiation. H3K9me3, a histone methylation characteristic of heterochromatin, also increases in ACMs and at E2F-dependent promoters. We hypothesize that genes relevant for cardiac proliferation are targeted to heterochromatin by retinoblastoma (Rb) family members interacting with E2F transcription factors and recruiting heterochromatin protein 1 (HP1) proteins. To test this hypothesis, we created cardiac-specific Rb and p130 inducible double knockout (IDKO) mice. IDKO ACMs showed a decrease in total heterochromatin, and cell cycle genes were derepressed, leading to proliferation of ACMs. Although Rb/p130 deficiency had no effect on total H3K9me3 levels, recruitment of HP1-γ to promoters was lost. Depleting HP1-γ up-regulated proliferation-promoting genes in ACMs. Thus, Rb and p130 have overlapping roles in maintaining the postmitotic state of ACMs through their interaction with HP1-γ to direct heterochromatin formation and silencing of proliferation-promoting genes.
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Affiliation(s)
- Patima Sdek
- Cardiovascular Research Laboratory, Department of Medicine and Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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Abstract
Since the fundamental defect in both type 1 and type 2 diabetes is β-cell failure, there is increasing interest in the capacity, if any, for β-cell regeneration. Insights into typical β-cell age and lifespan during normal development and how these are influenced in diabetes is desirable to realistically establish the prospects for β-cell regeneration as means to reverse the deficit in β-cell mass in diabetes. We assessed the mean β-cell age and lifespan by the classical McKendrick-von Foester equation that describes the age-based heterogeneity of β-cells in terms of the time-varying β-cell formation and loss estimated by a β-cell turnover model. This modeling approach was applied to evaluate β-cell lifespan in a rodent model of type 2 diabetes in comparison with nondiabetic controls. When rats were 10 mo old, mean β-cell lifespan was 1 mo vs. 6 mo in rats with type 2 diabetes vs. controls. A shortened β-cell lifespan in a rat model of type 2 diabetes results in a decrease in mean β-cell age and thus contributes to decreased β-cell mass.
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Affiliation(s)
- Erica Manesso
- Dept. of Information Engineering, Univ. of Padova, Via Gradenigo 6 B, 35129 Padova, Italy
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Abstract
OBJECTIVE Cyclin-dependent kinase 5 (CDK5) regulatory subunit-associated protein 1-like 1 has recently been linked to type 2 diabetes by genome-wide association studies. While CDK5 and its regulatory protein p35 are both expressed and display enzymatic activity in pancreatic β-cells, their precise role in the β-cell remains unknown. Because type 2 diabetes is characterized by a deficit in β-cell mass and increased β-cell apoptosis, we investigated the role of CDK5 in β-cell survival. RESEARCH DESIGN AND METHODS We used INS 832/13 cells, rat islets isolated from wild-type or human islet amyloid polypeptide (h-IAPP) transgenic rats, and pancreatic tissue from rats and humans with and without type 2 diabetes and investigated the effect of CDK5/p35 inhibition (by small interfering RNA or by chemical inhibition) as well as CDK5/p35 overexpression on β-cell vulnerability to apoptosis. RESULTS CDK5 inhibition led to increased β-cell apoptosis. To identify the mechanisms involved, we examined the phosphorylation state of focal adhesion kinase (Fak)(Ser732), a known target of CDK5. Following CDK5 inhibition, the phosphorylation of Fak(Ser732) decreased with resulting attenuation of phosphatidylinositol 3-kinase (PI3K)/Akt survival pathway. Conversely, CDK5 overexpression increased Fak(Ser732) phosphorylation and protected β-cells against apoptosis induced by the inhibition of the β-1 integrin signaling pathway. Also, Fak(Ser732) phosphorylation was less abundant in β-cells in both h-IAPP transgenic rats and humans with type 2 diabetes. CONCLUSIONS This study shows that by regulating Fak phosphorylation and subsequently PI3K/Akt survival pathway, CDK5 plays a previously unrecognized role in promoting β-cell survival.
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Affiliation(s)
- Marie Daval
- Larry Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California, USA.
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Saisho Y, Manesso E, Butler AE, Galasso R, Kavanagh K, Flynn M, Zhang L, Clark P, Gurlo T, Toffolo GM, Cobelli C, Wagner JD, Butler PC. Ongoing beta-cell turnover in adult nonhuman primates is not adaptively increased in streptozotocin-induced diabetes. Diabetes 2011; 60:848-56. [PMID: 21270238 PMCID: PMC3046845 DOI: 10.2337/db09-1368] [Citation(s) in RCA: 31] [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] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE β-Cell turnover and its potential to permit β-cell regeneration in adult primates are unknown. Our aims were 1) to measure β-cell turnover in adult nonhuman primates; 2) to establish the relative contribution of β-cell replication and formation of new β-cells from other precursors (defined thus as β-cell neogenesis); and 3) to establish whether there is an adaptive increase in β-cell formation (attempted regeneration) in streptozotocin (STZ)-induced diabetes in adult nonhuman primates. RESEARCH DESIGN AND METHODS Adult (aged 7 years) vervet monkeys were administered STZ (45-55 mg/kg, n = 7) or saline (n = 9). Pancreas was obtained from each animal twice, first by open surgical biopsy and then by euthanasia. β-Cell turnover was evaluated by applying a mathematic model to measured replication and apoptosis rates. RESULTS β-Cell turnover is present in adult nonhuman primates (3.3 ± 0.9 mg/month), mostly (~80%) derived from β-cell neogenesis. β-Cell formation was minimal in STZ-induced diabetes. Despite marked hyperglycemia, β-cell apoptosis was not increased in monkeys administered STZ. CONCLUSIONS There is ongoing β-cell turnover in adult nonhuman primates that cannot be accounted for by β-cell replication. There is no evidence of β-cell regeneration in monkeys administered STZ. Hyperglycemia does not induce β-cell apoptosis in nonhuman primates in vivo.
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Affiliation(s)
- Yoshifumi Saisho
- Larry Hillblom Islet Research Center, UCLA David Geffen School of Medicine, Los Angeles, California
| | - Erica Manesso
- Larry Hillblom Islet Research Center, UCLA David Geffen School of Medicine, Los Angeles, California
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Alexandra E. Butler
- Larry Hillblom Islet Research Center, UCLA David Geffen School of Medicine, Los Angeles, California
| | - Ryan Galasso
- Larry Hillblom Islet Research Center, UCLA David Geffen School of Medicine, Los Angeles, California
| | - Kylie Kavanagh
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Mickey Flynn
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Li Zhang
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Paige Clark
- Department of Radiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Tatyana Gurlo
- Larry Hillblom Islet Research Center, UCLA David Geffen School of Medicine, Los Angeles, California
| | - Gianna M. Toffolo
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Claudio Cobelli
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Janice D. Wagner
- Department of Pathology, Wake Forest University School of Medicine, Winston-Salem, North Carolina
| | - Peter C. Butler
- Larry Hillblom Islet Research Center, UCLA David Geffen School of Medicine, Los Angeles, California
- Corresponding author: Peter C. Butler,
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Costes S, Huang CJ, Gurlo T, Daval M, Matveyenko AV, Rizza RA, Butler AE, Butler PC. β-cell dysfunctional ERAD/ubiquitin/proteasome system in type 2 diabetes mediated by islet amyloid polypeptide-induced UCH-L1 deficiency. Diabetes 2011; 60:227-38. [PMID: 20980462 PMCID: PMC3012175 DOI: 10.2337/db10-0522] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [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: 04/12/2010] [Accepted: 10/14/2010] [Indexed: 12/20/2022]
Abstract
OBJECTIVE The islet in type 2 diabetes is characterized by β-cell apoptosis, β-cell endoplasmic reticulum stress, and islet amyloid deposits derived from islet amyloid polypeptide (IAPP). Toxic oligomers of IAPP form intracellularly in β-cells in humans with type 2 diabetes, suggesting impaired clearance of misfolded proteins. In this study, we investigated whether human-IAPP (h-IAPP) disrupts the endoplasmic reticulum-associated degradation/ubiquitin/proteasome system. RESEARCH DESIGN AND METHODS We used pancreatic tissue from humans with and without type 2 diabetes, isolated islets from h-IAPP transgenic rats, isolated human islets, and INS 832/13 cells transduced with adenoviruses expressing either h-IAPP or a comparable expression of rodent-IAPP. Immunofluorescence and Western blotting were used to detect polyubiquitinated proteins and ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) protein levels. Proteasome activity was measured in isolated rat and human islets. UCH-L1 was knocked down by small-interfering RNA in INS 832/13 cells and apoptosis was evaluated. RESULTS We report accumulation of polyubiquinated proteins and UCH-L1 deficiency in β-cells of humans with type 2 diabetes. These findings were reproduced by expression of oligomeric h-IAPP but not soluble rat-IAPP. Downregulation of UCH-L1 expression and activity to reproduce that caused by h-IAPP in β-cells induced endoplasmic reticulum stress leading to apoptosis. CONCLUSIONS Our results indicate that defective protein degradation in β-cells in type 2 diabetes can, at least in part, be attributed to misfolded h-IAPP leading to UCH-L1 deficiency, which in turn further compromises β-cell viability.
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Affiliation(s)
- Safia Costes
- Larry Hillblom Islet Research Center, University of California, Los Angeles, USA.
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