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Henquin JC. The challenge of correctly reporting hormones content and secretion in isolated human islets. Mol Metab 2019; 30:230-239. [PMID: 31767174 PMCID: PMC6829677 DOI: 10.1016/j.molmet.2019.10.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 09/28/2019] [Accepted: 10/07/2019] [Indexed: 12/30/2022] Open
Abstract
Background An increased access of research laboratories to isolated human islets has improved our understanding of the biology of the endocrine pancreas and hence the mechanisms causing diabetes. However, in vitro studies of human islets remain technically challenging, and optimal use of such precious material requires a minimum of rigor and coordination to optimize the reliability and share of the information. A detailed report of the demographics of pancreas donors and of the procedures of islet handling after isolation is important but insufficient. Correct characterization of islet basic functions (a token of quality) at the time of experimentation is also crucial. Scope of review I have analyzed the literature reporting measurements of insulin and glucagon in the human pancreas or isolated human islets. The published information is often fragmentary. Elementary features such as islet size, insulin content, or rate of hormone secretion are either unreported or incorrectly reported in many papers. Although internal comparisons between control and test groups may remain valid, comparisons with data from other laboratories are problematic. The drawbacks, pitfalls and errors of common ways of expressing hormone content or secretion rates are discussed and alternatives to harmonize data presentation are proposed. Major Conclusions Greater coherence and rigor in the report of in vitro studies using human islets are necessary to ensure optimal progress in our understanding of the pathogenesis of diabetes.
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Affiliation(s)
- Jean-Claude Henquin
- Unit of Endocrinology and Metabolism, Faculty of Medicine, University of Louvain, Brussels, Belgium.
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Abstract
PURPOSE OF REVIEW This review summarizes the alterations in the β-cell observed in type 2 diabetes (T2D), focusing on changes in β-cell identity and mass and changes associated with metabolism and intracellular signaling. RECENT FINDINGS In the setting of T2D, β-cells undergo changes in gene expression, reverting to a more immature state and in some cases transdifferentiating into other islet cell types. Alleviation of metabolic stress, ER stress, and maladaptive prostaglandin signaling could improve β-cell function and survival. The β-cell defects leading to T2D likely differ in different individuals and include variations in β-cell mass, development, β-cell expansion, responses to ER and oxidative stress, insulin production and secretion, and intracellular signaling pathways. The recent recognition that some β-cells undergo dedifferentiation without dying in T2D suggests strategies to revive these cells and rejuvenate their functionality.
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Affiliation(s)
- Ashley A Christensen
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37232, USA
| | - Maureen Gannon
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37232, USA.
- Department of Medicine, Vanderbilt University Medical Center, 2213 Garland Ave, MRB IV 7465, Nashville, TN, 37232, USA.
- Department of Veterans Affairs, Tennessee Valley Health Authority, Nashville, TN, 37232, USA.
- Department of Cell & Developmental Biology, Vanderbilt University, Nashville, TN, 37232, USA.
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53
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Yoon H, Yoon YS, Kim SG, Oh HJ, Choi CW, Seong JM, Park J. Relationship between metabolic syndrome and metabolic syndrome score with β-cell function by gender in non-diabetic Korean populations. Endocr Res 2019; 44:71-80. [PMID: 30339044 DOI: 10.1080/07435800.2018.1524476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Aims: The present study was conducted to assess the association of metabolic syndrome (MetS) and the MetS score (MSS) with β-cell function by gender in Korean non-diabetic populations. Methods: This study used the data from the 2015 Korean National Health and Nutrition Examination Survey including 4380 adults, aged 20 or older. Results: After adjusting for related variables (with exception of body mass index [BMI]), MetS (p < 0.001) and MSS (p < 0.001) were positively associated with homeostasis model assessment of β-cell function (HOMA-B), in both men and women. When further adjusting for BMI, MetS (p = 0.002) and MSS (p = 0.006) were positively associated with HOMA-B in women, whereas the association of MetS (p = 0.140) or MSS (p = 0.697) and HOMA-B was no longer significant in men. Conclusion: MetS and MSS increases were positively associated with β-cell function in non-diabetic Korean women, but not in non-diabetic Korean men.
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Affiliation(s)
- Hyun Yoon
- a Department of Biomedical Laboratory Science , Hanlyo University , Gwangyangsi , Jeollanamdo , South Korea
| | - Yo Sang Yoon
- b Department of Radiological Science , Hanlyo University , Gwangyangsi , Jeollanamdo , South Korea
| | - Sung Gil Kim
- b Department of Radiological Science , Hanlyo University , Gwangyangsi , Jeollanamdo , South Korea
| | - Hye Jong Oh
- a Department of Biomedical Laboratory Science , Hanlyo University , Gwangyangsi , Jeollanamdo , South Korea
| | - Cheol Won Choi
- a Department of Biomedical Laboratory Science , Hanlyo University , Gwangyangsi , Jeollanamdo , South Korea
| | - Jeong Min Seong
- c Department of Dental Hygiene , College of Health Science, Kangwon National University , Samcheok-si , Gangwon-do , South Korea
| | - Jong Park
- d Department of Preventive Medicine , Chosun University Medical School , Gwangju , South Korea
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54
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Fu J, Githaka JM, Dai X, Plummer G, Suzuki K, Spigelman AF, Bautista A, Kim R, Greitzer-Antes D, Fox JEM, Gaisano HY, MacDonald PE. A glucose-dependent spatial patterning of exocytosis in human β-cells is disrupted in type 2 diabetes. JCI Insight 2019; 5:127896. [PMID: 31085831 DOI: 10.1172/jci.insight.127896] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Impaired insulin secretion in type 2 diabetes (T2D) is linked to reduced insulin granule docking, disorganization of the exocytotic site, and an impaired glucose-dependent facilitation of insulin exocytosis. We show in β-cells from 80 human donors that the glucose-dependent amplification of exocytosis is disrupted in T2D. Spatial analyses of granule fusion, visualized by total internal reflection fluorescence (TIRF) microscopy in 24 of these donors, demonstrate that these are non-random across the surface of β-cells from donors with no diabetes (ND). The compartmentalization of events occurs within regions defined by concurrent or recent membrane-resident secretory granules. This organization, and the number of membrane-associated granules, is glucose-dependent and notably impaired in T2D β-cells. Mechanistically, multi-channel Kv2.1 clusters contribute to maintaining the density of membrane-resident granules and the number of fusion 'hotspots', while SUMOylation sites at the channel N- (K145) and C-terminus (K470) determine the relative proportion of fusion events occurring within these regions. Thus, a glucose-dependent compartmentalization of fusion, regulated in part by a structural role for Kv2.1, is disrupted in β-cells from donors with type 2 diabetes.
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Affiliation(s)
- Jianyang Fu
- Alberta Diabetes Institute and Department of Pharmacology and
| | | | - Xiaoqing Dai
- Alberta Diabetes Institute and Department of Pharmacology and
| | - Gregory Plummer
- Alberta Diabetes Institute and Department of Pharmacology and
| | - Kunimasa Suzuki
- Alberta Diabetes Institute and Department of Pharmacology and
| | | | - Austin Bautista
- Alberta Diabetes Institute and Department of Pharmacology and
| | - Ryekjang Kim
- Alberta Diabetes Institute and Department of Pharmacology and
| | - Dafna Greitzer-Antes
- Departments of Medicine and Physiology, University of Toronto, Toronto, Ontario, Canada
| | | | - Herbert Y Gaisano
- Departments of Medicine and Physiology, University of Toronto, Toronto, Ontario, Canada
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55
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Zhu L, Dattaroy D, Pham J, Wang L, Barella LF, Cui Y, Wilkins KJ, Roth BL, Hochgeschwender U, Matschinsky FM, Kaestner KH, Doliba NM, Wess J. Intra-islet glucagon signaling is critical for maintaining glucose homeostasis. JCI Insight 2019; 5:127994. [PMID: 31012868 DOI: 10.1172/jci.insight.127994] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Glucagon, a hormone released from pancreatic alpha-cells, plays a key role in maintaining proper glucose homeostasis and has been implicated in the pathophysiology of diabetes. In vitro studies suggest that intra-islet glucagon can modulate the function of pancreatic beta-cells. However, because of the lack of suitable experimental tools, the in vivo physiological role of this intra-islet cross-talk has remained elusive. To address this issue, we generated a novel mouse model that selectively expressed an inhibitory designer G protein-coupled receptor (Gi DREADD) in α-cells only. Drug-induced activation of this inhibitory designer receptor almost completely shut off glucagon secretion in vivo, resulting in significantly impaired insulin secretion, hyperglycemia, and glucose intolerance. Additional studies with mouse and human islets indicated that intra-islet glucagon stimulates insulin release primarily by activating β-cell GLP-1 receptors. These new findings strongly suggest that intra-islet glucagon signaling is essential for maintaining proper glucose homeostasis in vivo. Our work may pave the way toward the development of novel classes of antidiabetic drugs that act by modulating intra-islet cross-talk between α- and β-cells.
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Affiliation(s)
- Lu Zhu
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Diptadip Dattaroy
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Jonathan Pham
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Lingdi Wang
- Laboratory of Mitochondrial Biology and Metabolism, National Heart, Lung and Blood Institute, Bethesda, Maryland, USA
| | - Luiz F Barella
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Yinghong Cui
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
| | - Kenneth J Wilkins
- Biostatistics Program, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, Maryland, USA
| | - Bryan L Roth
- Department of Pharmacology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
| | - Ute Hochgeschwender
- Neuroscience Program and College of Medicine, Central Michigan University, Mt. Pleasant, Michigan, USA
| | - Franz M Matschinsky
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Klaus H Kaestner
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Nicolai M Doliba
- Institute of Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland, USA
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56
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Elksnis A, Martinell M, Eriksson O, Espes D. Heterogeneity of Metabolic Defects in Type 2 Diabetes and Its Relation to Reactive Oxygen Species and Alterations in Beta-Cell Mass. Front Physiol 2019; 10:107. [PMID: 30837889 PMCID: PMC6383038 DOI: 10.3389/fphys.2019.00107] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/28/2019] [Indexed: 12/21/2022] Open
Abstract
Type 2 diabetes (T2D) is a complex and heterogeneous disease which affects millions of people worldwide. The classification of diabetes is at an interesting turning point and there have been several recent reports on sub-classification of T2D based on phenotypical and metabolic characteristics. An important, and perhaps so far underestimated, factor in the pathophysiology of T2D is the role of oxidative stress and reactive oxygen species (ROS). There are multiple pathways for excessive ROS formation in T2D and in addition, beta-cells have an inherent deficit in the capacity to cope with oxidative stress. ROS formation could be causal, but also contribute to a large number of the metabolic defects in T2D, including beta-cell dysfunction and loss. Currently, our knowledge on beta-cell mass is limited to autopsy studies and based on comparisons with healthy controls. The combined evidence suggests that beta-cell mass is unaltered at onset of T2D but that it declines progressively. In order to better understand the pathophysiology of T2D, to identify and evaluate novel treatments, there is a need for in vivo techniques able to quantify beta-cell mass. Positron emission tomography holds great potential for this purpose and can in addition map metabolic defects, including ROS activity, in specific tissue compartments. In this review, we highlight the different phenotypical features of T2D and how metabolic defects impact oxidative stress and ROS formation. In addition, we review the literature on alterations of beta-cell mass in T2D and discuss potential techniques to assess beta-cell mass and metabolic defects in vivo.
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Affiliation(s)
- Andris Elksnis
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Mats Martinell
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Olof Eriksson
- Science for Life Laboratory, Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
| | - Daniel Espes
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
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57
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Rogal J, Zbinden A, Schenke-Layland K, Loskill P. Stem-cell based organ-on-a-chip models for diabetes research. Adv Drug Deliv Rev 2019; 140:101-128. [PMID: 30359630 DOI: 10.1016/j.addr.2018.10.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 09/10/2018] [Accepted: 10/19/2018] [Indexed: 12/22/2022]
Abstract
Diabetes mellitus (DM) ranks among the severest global health concerns of the 21st century. It encompasses a group of chronic disorders characterized by a dysregulated glucose metabolism, which arises as a consequence of progressive autoimmune destruction of pancreatic beta-cells (type 1 DM), or as a result of beta-cell dysfunction combined with systemic insulin resistance (type 2 DM). Human cohort studies have provided evidence of genetic and environmental contributions to DM; yet, these studies are mostly restricted to investigating statistical correlations between DM and certain risk factors. Mechanistic studies, on the other hand, aimed at re-creating the clinical picture of human DM in animal models. A translation to human biology is, however, often inadequate owing to significant differences between animal and human physiology, including the species-specific glucose regulation. Thus, there is an urgent need for the development of advanced human in vitro models with the potential to identify novel treatment options for DM. This review provides an overview of the technological advances in research on DM-relevant stem cells and their integration into microphysiological environments as provided by the organ-on-a-chip technology.
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Affiliation(s)
- Julia Rogal
- Department of Women's Health, Research Institute for Women's Health, Eberhard Karls University, Silcherstrasse 7/1, 72076 Tübingen, Germany; Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB, Nobelstrasse 12, 70569 Stuttgart, Germany
| | - Aline Zbinden
- Department of Women's Health, Research Institute for Women's Health, Eberhard Karls University, Silcherstrasse 7/1, 72076 Tübingen, Germany
| | - Katja Schenke-Layland
- Department of Women's Health, Research Institute for Women's Health, Eberhard Karls University, Silcherstrasse 7/1, 72076 Tübingen, Germany; The Natural and Medical Sciences Institute (NMI) at the University of Tübingen, Markwiesenstr. 55, 72770 Reutlingen, Germany; Department of Medicine/Cardiology, Cardiovascular Research Laboratories, David Geffen School of Medicine at UCLA, 675 Charles E. Young Drive South, MRL 3645, Los Angeles, CA, USA.
| | - Peter Loskill
- Department of Women's Health, Research Institute for Women's Health, Eberhard Karls University, Silcherstrasse 7/1, 72076 Tübingen, Germany; Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB, Nobelstrasse 12, 70569 Stuttgart, Germany
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58
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Hyaluronic acid enhances cell survival of encapsulated insulin-producing cells in alginate-based microcapsules. Int J Pharm 2019; 557:192-198. [DOI: 10.1016/j.ijpharm.2018.12.062] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 12/13/2018] [Accepted: 12/15/2018] [Indexed: 12/18/2022]
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59
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Belikov AV. Age-related diseases as vicious cycles. Ageing Res Rev 2019; 49:11-26. [PMID: 30458244 DOI: 10.1016/j.arr.2018.11.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 10/05/2018] [Accepted: 11/15/2018] [Indexed: 02/07/2023]
Abstract
The mortality rates of age-related diseases (ARDs) increase exponentially with age. Processes described by the exponential growth function typically involve a branching chain reaction or, more generally, a positive feedback loop. Here I propose that each ARD is mediated by one or several positive feedback loops (vicious cycles). I then identify critical vicious cycles in five major ARDs: atherosclerosis, hypertension, diabetes, Alzheimer's and Parkinson's. I also propose that the progression of ARDs can be halted by selectively interrupting the vicious cycles and suggest the most promising targets.
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Affiliation(s)
- Aleksey V Belikov
- Laboratory of Innovative Medicine, School of Biological and Medical Physics, Moscow Institute of Physics and Technology, Institutsky per., 9, 141701 Dolgoprudny, Moscow Region, Russia.
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60
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Metabolic effects of glucagon in humans. JOURNAL OF CLINICAL AND TRANSLATIONAL ENDOCRINOLOGY 2018; 15:45-53. [PMID: 30619718 PMCID: PMC6312800 DOI: 10.1016/j.jcte.2018.12.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 12/13/2018] [Accepted: 12/13/2018] [Indexed: 01/09/2023]
Abstract
Diabetes is a common metabolic disorder that involves glucose, amino acids, and fatty acids. Either insulin deficiency or insulin resistance may cause diabetes. Insulin deficiency causes type 1 diabetes and diabetes associated with total pancreatectomy. Glucagon produces insulin resistance. Glucagon-induced insulin resistance promotes type 2 diabetes and diabetes associated with glucagonoma. Further, glucagon-induced insulin resistance aggravates the metabolic consequences of the insulin-deficient state. A major metabolic effect of insulin is the accumulation of glucose as glycogen in the liver. Glucagon opposes hepatic insulin action and enhances the rate of gluconeogenesis, increasing hepatic glucose output. In order to support gluconeogenesis, glucagon promotes skeletal muscle wasting to supply amino acids as gluconeogenic precursors. Glucagon promotes hepatic fatty acid oxidation to supply energy required to sustain gluconeogenesis. Hepatic fatty acid oxidation generates β-hydroxybutyrate and acetoacetate (ketogenesis). Prospective studies reveal that elevated glucagon secretion at baseline occurs in healthy subjects who develop impaired glucose tolerance at follow-up compared with subjects who maintain normal glucose tolerance, suggesting a relationship between elevated glucagon secretion and development of impaired glucose tolerance. Prospective studies have identified animal protein consumption as an independent risk factor for type 2 diabetes and cardiovascular disease. Animal protein intake activates glucagon secretion inducing sustained elevations in plasma glucagon. Glucagon is a major hormone that causes insulin resistance. Insulin resistance is an established cardiovascular risk factor additionally to its pathogenic role in diabetes. Glucagon may be a potential link between animal protein intake and the risk of developing type 2 diabetes and cardiovascular disease.
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61
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Anjani PP, Damayanthi E, Rimbawan, Handharyani E. Antidiabetic potential of purple okra (Abelmoschus esculentus L.) extract in streptozotocin-induced diabetic rats. ACTA ACUST UNITED AC 2018. [DOI: 10.1088/1755-1315/196/1/012038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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62
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Liu W, Aerbajinai W, Li H, Liu Y, Gavrilova O, Jain S, Rodgers GP. Olfactomedin 4 Deletion Improves Male Mouse Glucose Intolerance and Insulin Resistance Induced by a High-Fat Diet. Endocrinology 2018; 159:3235-3244. [PMID: 30052841 PMCID: PMC6098226 DOI: 10.1210/en.2018-00451] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 07/13/2018] [Indexed: 01/09/2023]
Abstract
Glucose-stimulated insulin secretion (GSIS) is essential for blood glucose homeostasis and is impaired in type 2 diabetes mellitus. Understanding the regulatory components of GSIS has clinical implications for diabetes treatment. In this study, we found that olfactomedin 4 (OLFM4) is endogenously expressed in pancreatic islet β cells and further investigated its potential roles in glucose homeostasis and the pathogenesis of type 2 diabetes using mouse models. Olfm4-deficient mice showed significantly improved glucose tolerance and significantly increased insulin levels after glucose challenge compared with wild-type (WT) mice. GSIS, mitochondrial ATP production, and mitochondrial respiration were all significantly increased in islets isolated from Olfm4-deficient mice compared with those isolated from WT mice. In a high-fat diet (HFD)-induced diabetic mouse model, the increase in insulin levels after glucose challenge was significantly higher in Olfm4-deficient mice compared with WT mice. The impaired glucose tolerance and insulin resistance in HFD-fed mice were improved by loss of Olfm4. Olfm4 was found to be mainly localized in the mitochondria and interacts with GRIM-19 (a gene associated with retinoid-interferon mortality) in Min6 pancreatic β cells. Collectively, these studies suggest that Olfm4 negatively regulates GSIS. OLFM4 may represent a potential therapeutic target for impaired glucose tolerance and patients with type 2 diabetes.
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Affiliation(s)
- Wenli Liu
- Molecular and Clinical Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
- Correspondence: Wenli Liu, MD, Molecular and Clinical Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Building 10, Room 9N113, 9000 Rockville Pike, Bethesda, Maryland 20892. E-mail:
| | - Wulin Aerbajinai
- Molecular and Clinical Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Hongzhen Li
- Molecular and Clinical Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
| | - Yueqin Liu
- Critical Care Medicine Department, Clinical Center, National Institutes of Health, Bethesda, Maryland
| | - Oksana Gavrilova
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Shalini Jain
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Griffin P Rodgers
- Molecular and Clinical Hematology Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland
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63
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Komariah K, Manalu W, Kiranadi B, Winarto A, Handharyani E, Roeslan MO. Valproic Acid Exposure of Pregnant Rats During Organogenesis Disturbs Pancreas Development in Insulin Synthesis and Secretion of the Offspring. Toxicol Res 2018; 34:173-182. [PMID: 29686779 PMCID: PMC5903136 DOI: 10.5487/tr.2018.34.2.173] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 11/26/2017] [Accepted: 03/09/2018] [Indexed: 12/19/2022] Open
Abstract
Valproic acid (VPA) plays a role in histone modifications that eventually inhibit the activity of histone deacetylase (HDAC), and will affect the expressions of genes Pdx1, Nkx6.1, and Ngn3 during pancreatic organogenesis. This experiment was designed to study the effect of VPA exposure in pregnant rats on the activity of HDAC that controls the expression of genes regulating the development of beta cells in the pancreas to synthesize and secrete insulin. This study used 30 pregnant Sprague-Dawley rats, divided into 4 groups, as follows: (1) a control group of pregnant rats without VPA administration, (2) pregnant rats administered with 250 mg VPA on day 10 of pregnancy, (3) pregnant rats administered with 250 mg VPA on day 13 of pregnancy, and (4) pregnant rats administered with 250 mg VPA on day 16 of pregnancy. Eighty-four newborn rats born to control rats and rats administered with VPA on days 10, 13, and 16 of pregnancy were used to measure serum glucose, insulin, DNA, RNA, and ratio of RNA/DNA concentrations in the pancreas and to observe the microscopical condition of the pancreas at the ages of 4 to 32 weeks postpartum with 4-week intervals. The results showed that at the age of 32 weeks, the offspring of pregnant rats administered with 250 mg VPA on days 10, 13, and 16 of pregnancy had higher serum glucose concentrations and lower serum insulin concentrations, followed by decreased concentrations of RNA, and the ratio of RNA/DNA in the pancreas. Microscopical observations showed that the pancreas of the rats born to pregnant rats administered with VPA during pregnancy had low immunoreaction to insulin. The exposure of pregnant rats to VPA during pregnancy disturbs organogenesis of the pancreas of the embryos that eventually disturb the insulin production in the beta cells indicated by the decreased insulin secretion during postnatal life.
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Affiliation(s)
- Komariah Komariah
- Department of Histology, Faculty of Dentistry, Trisakti University, West Jakarta, Indonesia
| | - Wasmen Manalu
- Department of Anatomy, Physiology, and Pharmacology, Faculty of Veterinary Medicine, Bogor Agricultural University, West Java, Indonesia
| | - Bambang Kiranadi
- Department of Anatomy, Physiology, and Pharmacology, Faculty of Veterinary Medicine, Bogor Agricultural University, West Java, Indonesia
| | - Adi Winarto
- Department of Anatomy, Physiology, and Pharmacology, Faculty of Veterinary Medicine, Bogor Agricultural University, West Java, Indonesia
| | - Ekowati Handharyani
- Department of Clinic, Reproduction, and Pathology, Faculty of Veterinary Medicine, Bogor Agricultural University, West Java, Indonesia
| | - M Orliando Roeslan
- Department of Biology Oral, Faculty of Dentistry, Trisakti University, West Jakarta, Indonesia
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64
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Lundberg M, Stenwall A, Tegehall A, Korsgren O, Skog O. Expression profiles of stress-related genes in islets from donors with progressively impaired glucose metabolism. Islets 2018; 10:69-79. [PMID: 29446696 PMCID: PMC5895176 DOI: 10.1080/19382014.2018.1433980] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
It is currently unknown how the islet transcriptional pattern changes as glucose metabolism deteriorates and progresses to fulminant type 2 diabetes (T2D). In this study, we hypothesized that islets from donors with elevated HbA1c levels, but not yet diagnosed with T2D, would show signs of cell stress on a transcriptional level. Laser capture microdissection and qPCR arrays including 330 genes related to mitochondria, oxidative stress, or the unfolded protein response were used to extract and analyze islets from organ donors with HbA1c <5.5% (37 mmol/mol), elevated HbA1c (6.0-6.5% (42-48 mmol/mol)), high HbA1c (>6.5% (48 mmol/mol)) or established T2D. Principal component analysis and hierarchical clustering based on the expression of all 330 genes displayed no obvious separation of the four different donor groups, indicating that the inter-donor variations were larger than the differences between groups. However, 44 genes were differentially expressed (P < 0.05, false discovery rate <30%) between islets from donors with HbA1c <5.5% (37 mmol/mol) compared with islets from T2D subjects. Twelve genes were differentially expressed compared to control islets in both donors with established T2D and donors with elevated HbA1c (6.0-6.5% (42-48 mmol/mol)). Overexpressed genes were related mainly to the unfolded protein response, whereas underexpressed genes were related to mitochondria. Our data on transcriptional changes in human islets retrieved by LCM from high-quality biopsies, as pre-diabetes progresses to established T2D, increase our understanding on how islet stress contributes to the disease development.
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Affiliation(s)
- Marcus Lundberg
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
- CONTACT Marcus Lundberg Uppsala University, Department of Immunology, Genetics and Pathology, The Rudbeck Laboratory C11, 751 85 Uppsala, Sweden
| | - Anton Stenwall
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Angie Tegehall
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - Olle Korsgren
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
- Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Oskar Skog
- Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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Fex M, Nicholas LM, Vishnu N, Medina A, Sharoyko VV, Nicholls DG, Spégel P, Mulder H. The pathogenetic role of β-cell mitochondria in type 2 diabetes. J Endocrinol 2018; 236:R145-R159. [PMID: 29431147 DOI: 10.1530/joe-17-0367] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 01/15/2018] [Indexed: 12/17/2022]
Abstract
Mitochondrial metabolism is a major determinant of insulin secretion from pancreatic β-cells. Type 2 diabetes evolves when β-cells fail to release appropriate amounts of insulin in response to glucose. This results in hyperglycemia and metabolic dysregulation. Evidence has recently been mounting that mitochondrial dysfunction plays an important role in these processes. Monogenic dysfunction of mitochondria is a rare condition but causes a type 2 diabetes-like syndrome owing to β-cell failure. Here, we describe novel advances in research on mitochondrial dysfunction in the β-cell in type 2 diabetes, with a focus on human studies. Relevant studies in animal and cell models of the disease are described. Transcriptional and translational regulation in mitochondria are particularly emphasized. The role of metabolic enzymes and pathways and their impact on β-cell function in type 2 diabetes pathophysiology are discussed. The role of genetic variation in mitochondrial function leading to type 2 diabetes is highlighted. We argue that alterations in mitochondria may be a culprit in the pathogenetic processes culminating in type 2 diabetes.
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Affiliation(s)
- Malin Fex
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
| | - Lisa M Nicholas
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
| | - Neelanjan Vishnu
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
| | - Anya Medina
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
| | - Vladimir V Sharoyko
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
| | - David G Nicholls
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
| | - Peter Spégel
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
- Department of ChemistryCenter for Analysis and Synthesis, Lund University, Sweden
| | - Hindrik Mulder
- Department of Clinical Sciences in MalmöUnit of Molecular Metabolism, Lund University Diabetes Centre, Clinical Research Center, Malmö University Hospital, Lund University, Malmö, Sweden
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66
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Bensellam M, Jonas JC, Laybutt DR. Mechanisms of β-cell dedifferentiation in diabetes: recent findings and future research directions. J Endocrinol 2018; 236:R109-R143. [PMID: 29203573 DOI: 10.1530/joe-17-0516] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 12/04/2017] [Indexed: 12/13/2022]
Abstract
Like all the cells of an organism, pancreatic β-cells originate from embryonic stem cells through a complex cellular process termed differentiation. Differentiation involves the coordinated and tightly controlled activation/repression of specific effectors and gene clusters in a time-dependent fashion thereby giving rise to particular morphological and functional cellular features. Interestingly, cellular differentiation is not a unidirectional process. Indeed, growing evidence suggests that under certain conditions, mature β-cells can lose, to various degrees, their differentiated phenotype and cellular identity and regress to a less differentiated or a precursor-like state. This concept is termed dedifferentiation and has been proposed, besides cell death, as a contributing factor to the loss of functional β-cell mass in diabetes. β-cell dedifferentiation involves: (1) the downregulation of β-cell-enriched genes, including key transcription factors, insulin, glucose metabolism genes, protein processing and secretory pathway genes; (2) the concomitant upregulation of genes suppressed or expressed at very low levels in normal β-cells, the β-cell forbidden genes; and (3) the likely upregulation of progenitor cell genes. These alterations lead to phenotypic reconfiguration of β-cells and ultimately defective insulin secretion. While the major role of glucotoxicity in β-cell dedifferentiation is well established, the precise mechanisms involved are still under investigation. This review highlights the identified molecular mechanisms implicated in β-cell dedifferentiation including oxidative stress, endoplasmic reticulum (ER) stress, inflammation and hypoxia. It discusses the role of Foxo1, Myc and inhibitor of differentiation proteins and underscores the emerging role of non-coding RNAs. Finally, it proposes a novel hypothesis of β-cell dedifferentiation as a potential adaptive mechanism to escape cell death under stress conditions.
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Affiliation(s)
- Mohammed Bensellam
- Garvan Institute of Medical ResearchSydney, New South Wales, Australia
- Université Catholique de LouvainInstitut de Recherche Expérimentale et Clinique, Pôle d'Endocrinologie, Diabète et Nutrition, Brussels, Belgium
| | - Jean-Christophe Jonas
- Université Catholique de LouvainInstitut de Recherche Expérimentale et Clinique, Pôle d'Endocrinologie, Diabète et Nutrition, Brussels, Belgium
| | - D Ross Laybutt
- Garvan Institute of Medical ResearchSydney, New South Wales, Australia
- St Vincent's Clinical SchoolUNSW Sydney, Sydney, New South Wales, Australia
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Zhu H, Zhang X, He Y, Yu L, Lü Y, Pan K, Wang B, Chen G. [Research progress on the donor cell sources of pancreatic islet transplantation for treatment of diabetes mellitus]. ZHONGGUO XIU FU CHONG JIAN WAI KE ZA ZHI = ZHONGGUO XIUFU CHONGJIAN WAIKE ZAZHI = CHINESE JOURNAL OF REPARATIVE AND RECONSTRUCTIVE SURGERY 2018; 32:104-111. [PMID: 29806374 DOI: 10.7507/1002-1892.201707049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Objective To summarize the research progress on the source and selection of donor cells in the field of islet replacement therapy for diabetes mellitus. Methods Domestic and abroad literature concerning islet replacement therapy for diabetes mellitus, as well as donor source and donor selection was reviewed and analyzed thoroughly. Results The shortage of donor supply is still a major obstacle for the widely clinical application of pancreatic islet transplantation (PIT). Currently, in addition to the progress on the allogeneic/autologous donor islet supply, some remarkable achievements have been also attained in the application of xenogeneic islet (from pig donor), as well as islet like cells derived from stem cells and islet cell line, potentially enlarging the source of implantable cells. Conclusion Adequate and suitable donor cell supply is an essential prerequisite for widely clinical application of PIT therapy for type 1 diabetes mellitus (T1DM). Further perfection of organ donation system, together with development of immune-tolerance induction, gene and bioengineering technology etc. will possibly solve the problem of donor cell shortage and provide a basis for clinical application of cellular replacement therapy for T1DM.
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Affiliation(s)
- Haitao Zhu
- Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital, Xi'an Shaanxi, 710061, P.R.China;Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an Shaanxi, 710061, P.R.China
| | - Xiaoge Zhang
- Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital, Xi'an Shaanxi, 710061, P.R.China
| | - Yayi He
- Department of Endocrinology, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an Shaanxi, 710061, P.R.China
| | - Liang Yu
- Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an Shaanxi, 710061, P.R.China
| | - Yi Lü
- Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an Shaanxi, 710061, P.R.China;Research Institute of Advanced Surgical Technology and Engineering, Xi'an Jiaotong University, Xi'an Shaanxi, 710061, P.R.China
| | - Kaili Pan
- Department of Pediatrics (No. 2 Ward), Northwest Women's and Children's Hospital, Xi'an Shaanxi, 710061, P.R.China
| | - Bo Wang
- Department of Hepatobiliary Surgery, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an Shaanxi, 710061, P.R.China;Department of Endocrinology, the First Affiliated Hospital, Medical School of Xi'an Jiaotong University, Xi'an Shaanxi, 710061,
| | - Guoqiang Chen
- Department of Pediatrics (No. 3 Ward), Northwest Women's and Children's Hospital, Xi'an Shaanxi, 710061,
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Kim GS, Kim SG, Kim HS, Hwang EY, Lee JH, Yoon H. The relationship between chronic kidney function and homeostasis model assessment of insulin resistance and beta cell function in Korean adults with or without type 2 diabetes mellitus. Endocr J 2017; 64:1181-1190. [PMID: 28890482 DOI: 10.1507/endocrj.ej17-0274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The present study was conducted to assess the relationship between chronic kidney disease (CKD) and the homeostasis model assessment of insulin resistance (HOMA-IR) and beta cell function (HOMA-B) in Korean adults with or without type 2 diabetes mellitus (T2DM). This study included 5,188 adults aged 20 or older using the 2015 Korea National Health and Nutrition Examination Survey (KNHANES) data, which represents national data in Korea. A covariance test adjusted for covariates was performed for HOMA-IR and HOMA-B in relation to CKD. The present study has several key findings. First, in T2DM, HOMA-IR (p = 0.035) was higher in the CKD group than in the non-CKD group after adjusting for the related variables but HOMA-B (p = 0.141) was not significant. Second, in non-T2DM, HOMA-IR (p = 0.163) and HOMA-B (p = 0.658) were not associated with CKD after adjusting for the related variables (except age). However, when further adjusted for age, HOMA-IR (p = 0.020) and HOMA-B (p = 0.006) were higher in the CKD group than in the non-CKD group. In conclusion, insulin resistance was positively associated CKD with in Korean adults with or without T2DM. Beta cell function was positively associated CKD with in Korean adults without T2DM but not in Korean adults with T2DM.
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Affiliation(s)
- Gwang Seok Kim
- Department of Emergency Medical Technology, Chungbuk Health and Science University, Cheongju-si 28150, South Korea
| | - Sung Gil Kim
- Department of Radiological Science, Hanlyo University, Gwangyang-si, 57764, South Korea
| | - Han Soo Kim
- Department of Health Science Graduate School, Chosun University, Gwangju 61457, South Korea
| | - Eun Young Hwang
- Department of Nursing Graduate School, Chosun University, Gwangju 61457, South Korea
| | - Jun Ho Lee
- Department of Biomedical Laboratory Science, Wonkwang Health Science University, Iksan-si, 54538, South Korea
| | - Hyun Yoon
- Department of Biomedical Laboratory Science, Hanlyo University, Gwangyang-si 57764, South Korea
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Hastoy B, Clark A, Rorsman P, Lang J. Fusion pore in exocytosis: More than an exit gate? A β-cell perspective. Cell Calcium 2017; 68:45-61. [PMID: 29129207 DOI: 10.1016/j.ceca.2017.10.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 10/17/2017] [Accepted: 10/24/2017] [Indexed: 12/14/2022]
Abstract
Secretory vesicle exocytosis is a fundamental biological event and the process by which hormones (like insulin) are released into the blood. Considerable progress has been made in understanding this precisely orchestrated sequence of events from secretory vesicle docked at the cell membrane, hemifusion, to the opening of a membrane fusion pore. The exact biophysical and physiological regulation of these events implies a close interaction between membrane proteins and lipids in a confined space and constrained geometry to ensure appropriate delivery of cargo. We consider some of the still open questions such as the nature of the initiation of the fusion pore, the structure and the role of the Soluble N-ethylmaleimide-sensitive-factor Attachment protein REceptor (SNARE) transmembrane domains and their influence on the dynamics and regulation of exocytosis. We discuss how the membrane composition and protein-lipid interactions influence the likelihood of the nascent fusion pore forming. We relate these factors to the hypothesis that fusion pore expansion could be affected in type-2 diabetes via changes in disease-related gene transcription and alterations in the circulating lipid profile. Detailed characterisation of the dynamics of the fusion pore in vitro will contribute to understanding the larger issue of insulin secretory defects in diabetes.
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Affiliation(s)
- Benoit Hastoy
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK.
| | - Anne Clark
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK; Metabolic Research, Institute of Neuroscience and Physiology, University of Goteborg, Medicinaregatan 11, S-41309 Göteborg, Sweden
| | - Jochen Lang
- Laboratoire de Chimie et Biologie des Membranes et Nano-objets (CBMN), CNRS UMR 5248, Université de Bordeaux, Allée de Geoffrey St Hilaire, 33600 Pessac, France.
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Insulin Resistance, Obesity and Lipotoxicity. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 960:277-304. [PMID: 28585204 DOI: 10.1007/978-3-319-48382-5_12] [Citation(s) in RCA: 273] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Lipotoxicity , originally used to describe the destructive effects of excess fat accumulation on glucose metabolism, causes functional impairments in several metabolic pathways, both in adipose tissue and peripheral organs, like liver, heart, pancreas and muscle. Lipotoxicity has roles in insulin resistance and pancreatic beta cell dysfunction. Increased circulating levels of lipids and the metabolic alterations in fatty acid utilization and intracellular signaling, have been related to insulin resistance in muscle and liver. Different pathways, like novel protein kinase c pathways and the JNK-1 pathway are involved as the mechanisms of how lipotoxicity leads to insulin resistance in nonadipose tissue organs, such as liver and muscle. Mitochondrial dysfunction plays a role in the pathogenesis of insulin resistance. Endoplasmic reticulum stress, through mainly increased oxidative stress, also plays important role in the etiology of insulin resistance, especially seen in non-alcoholic fatty liver disease. Visceral adiposity and insulin resistance both increase the cardiometabolic risk and lipotoxicity seems to play a crucial role in the pathophysiology of these associations.
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71
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Chen C, Cohrs CM, Stertmann J, Bozsak R, Speier S. Human beta cell mass and function in diabetes: Recent advances in knowledge and technologies to understand disease pathogenesis. Mol Metab 2017; 6:943-957. [PMID: 28951820 PMCID: PMC5605733 DOI: 10.1016/j.molmet.2017.06.019] [Citation(s) in RCA: 290] [Impact Index Per Article: 41.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/31/2017] [Accepted: 06/07/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Plasma insulin levels are predominantly the product of the morphological mass of insulin producing beta cells in the pancreatic islets of Langerhans and the functional status of each of these beta cells. Thus, deficiency in either beta cell mass or function, or both, can lead to insufficient levels of insulin, resulting in hyperglycemia and diabetes. Nonetheless, the precise contribution of beta cell mass and function to the pathogenesis of diabetes as well as the underlying mechanisms are still unclear. In the past, this was largely due to the restricted number of technologies suitable for studying the scarcely accessible human beta cells. However, in recent years, a number of new platforms have been established to expand the available techniques and to facilitate deeper insight into the role of human beta cell mass and function as cause for diabetes and as potential treatment targets. SCOPE OF REVIEW This review discusses the current knowledge about contribution of human beta cell mass and function to different stages of type 1 and type 2 diabetes pathogenesis. Furthermore, it highlights standard and newly developed technological platforms for the study of human beta cell biology, which can be used to increase our understanding of beta cell mass and function in human glucose homeostasis. MAJOR CONCLUSIONS In contrast to early disease models, recent studies suggest that in type 1 and type 2 diabetes impairment of beta cell function is an early feature of disease pathogenesis while a substantial decrease in beta cell mass occurs more closely to clinical manifestation. This suggests that, in addition to beta cell mass replacement for late stage therapies, the development of novel strategies for protection and recovery of beta cell function could be most promising for successful diabetes treatment and prevention. The use of today's developing and wide range of technologies and platforms for the study of human beta cells will allow for a more detailed investigation of the underlying mechanisms and will facilitate development of treatment approaches to specifically target human beta cell mass and function.
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Affiliation(s)
- Chunguang Chen
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Zentrum München at the University Clinic Carl Gustav Carus of Technische Universität Dresden, Helmholtz Zentrum München, München-Neuherberg, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Christian M. Cohrs
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Zentrum München at the University Clinic Carl Gustav Carus of Technische Universität Dresden, Helmholtz Zentrum München, München-Neuherberg, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Julia Stertmann
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Zentrum München at the University Clinic Carl Gustav Carus of Technische Universität Dresden, Helmholtz Zentrum München, München-Neuherberg, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Robert Bozsak
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Zentrum München at the University Clinic Carl Gustav Carus of Technische Universität Dresden, Helmholtz Zentrum München, München-Neuherberg, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
| | - Stephan Speier
- Paul Langerhans Institute Dresden (PLID) of Helmholtz Zentrum München at the University Clinic Carl Gustav Carus of Technische Universität Dresden, Helmholtz Zentrum München, München-Neuherberg, Germany
- German Center for Diabetes Research (DZD), München-Neuherberg, Germany
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Kim MK, Shin HM, Jung H, Lee E, Kim TK, Kim TN, Kwon MJ, Lee SH, Rhee BD, Park JH. Comparison of pancreatic beta cells and alpha cells under hyperglycemia: Inverse coupling in pAkt-FoxO1. Diabetes Res Clin Pract 2017; 131:1-11. [PMID: 28666105 DOI: 10.1016/j.diabres.2017.05.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 05/04/2017] [Accepted: 05/16/2017] [Indexed: 01/09/2023]
Abstract
Type 2 diabetes manifests beta cell deficiencies and alpha cell expansion which is consistent with relative insulin deficiency and glucagon oversecretion. The effects of hyperglycemia on alpha cells are not as understood in comparison to beta cells. Hyperglycemia increases oxidative stress, which induces Akt activation or FoxO activation, depending on cell type. Several studies independently reported that FoxO1 translocations in alpha cells and beta cells were opposite. We compared the responses of pancreatic alpha cells and beta cells against hyperglycemia. Alpha TC-1 cells and Beta TC-6 cells were incubated with control (5mM Glucose) or high glucose (33mM Glucose) with or without PI3K inhibitor or FoxO1 inhibitor. We assessed PI3K, pAkt and phosphorylated FoxO1 (pFoxO1) in both cell lines. Immunostaining of BrdU and FoxO1 was detected by green fluorescence microscopy and confocal microscopy. Hyperglycemia and H2O2 decreased PI3K and pAKT in beta cells, but increased them in alpha cells. FoxO1 localizations and pFoxO1 expressions between alpha cells and beta cells were opposite. Proliferation of beta cells was decreased, but alpha cell proliferation was increased under hyperglycemia. Antioxidant enzymes including superoxide dismutase (SOD) and catalase were increased in beta cells and they were reversed with FoxO1 inhibitor treatment. Increased proliferation in alpha cells under hyperglycemia was attenuated with PI3K inhibitor. In conclusion, hyperglycemia increased alpha cell proliferation and glucagon contents which are opposite to beta cells. These differences may be related to contrasting PI3K/pAkt changes in both cells and subsequent FoxO1 modulation.
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Affiliation(s)
- Mi-Kyung Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea; Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, South Korea.
| | - Hyun Mi Shin
- Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, South Korea
| | - HyeSook Jung
- Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, South Korea
| | - EunJu Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea
| | - Tae Kyoon Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea
| | - Tae Nyun Kim
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea
| | - Min Jeong Kwon
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea
| | - Soon Hee Lee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea
| | - Byoung Doo Rhee
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea
| | - Jeong Hyun Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Inje University, Busan, South Korea; Paik Institute for Clinical Research, Molecular Therapy Lab, Inje University, Busan, South Korea
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Doliba NM, Liu Q, Li C, Chen P, Liu C, Naji A, Matschinsky FM. Inhibition of cholinergic potentiation of insulin secretion from pancreatic islets by chronic elevation of glucose and fatty acids: Protection by casein kinase 2 inhibitor. Mol Metab 2017; 6:1240-1253. [PMID: 29031723 PMCID: PMC5641685 DOI: 10.1016/j.molmet.2017.07.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 07/24/2017] [Accepted: 07/31/2017] [Indexed: 01/24/2023] Open
Abstract
Objectives Chronic hyperlipidemia and hyperglycemia are characteristic features of type 2 diabetes (T2DM) that are thought to cause or contribute to β-cell dysfunction by “glucolipotoxicity.” Previously we have shown that acute treatment of pancreatic islets with fatty acids (FA) decreases acetylcholine-potentiated insulin secretion. This acetylcholine response is mediated by M3 muscarinic receptors, which play a key role in regulating β-cell function. Here we examine whether chronic FA exposure also inhibits acetylcholine-potentiated insulin secretion using mouse and human islets. Methods Islets were cultured for 3 or 4 days at different glucose concentration with 0.5 mM palmitic acid (PA) or a 2:1 mixture of PA and oleic acid (OA) at 1% albumin (PA/BSA molar ratio 3.3). Afterwards, the response to glucose and acetylcholine were studied in perifusion experiments. Results FA-induced impairment of insulin secretion and Ca2+ signaling depended strongly on the glucose concentrations of the culture medium. PA and OA in combination reduced acetylcholine potentiation of insulin secretion more than PA alone, both in mouse and human islets, with no evidence of a protective role of OA. In contrast, lipotoxicity was not observed with islets cultured for 3 days in medium containing less than 1 mM glucose and a mixture of glutamine and leucine (7 mM each). High glucose and FAs reduced endoplasmic reticulum (ER) Ca2+ storage capacity; however, preserving ER Ca2+ by blocking the IP3 receptor with xestospongin C did not protect islets from glucolipotoxic effects on insulin secretion. In contrast, an inhibitor of casein kinase 2 (CK2) protected the glucose dependent acetylcholine potentiation of insulin secretion in mouse and human islets against glucolipotoxicity. Conclusions These results show that chronic FA treatment decreases acetylcholine potentiation of insulin secretion and that this effect is strictly glucose dependent and might involve CK2 phosphorylation of β-cell M3 muscarinic receptors. Glucolipotoxicity impairs acetylcholine-potentiation of insulin secretion. Glucose amplification of insulin secretion rather than triggering is damaged by FA. Inhibitor of casein kinase 2 preserved islet function against glucolipotoxicity.
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Affiliation(s)
- Nicolai M Doliba
- Department of Biochemistry and Biophysics, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA; Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA.
| | - Qin Liu
- Department of Biochemistry and Biophysics, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA
| | - Changhong Li
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA; Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Pan Chen
- Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Chengyang Liu
- Department of Surgery, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA; Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA
| | - Ali Naji
- Department of Surgery, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA; Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA
| | - Franz M Matschinsky
- Department of Biochemistry and Biophysics, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA; Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA
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Li F, Munsey TS, Sivaprasadarao A. TRPM2-mediated rise in mitochondrial Zn 2+ promotes palmitate-induced mitochondrial fission and pancreatic β-cell death in rodents. Cell Death Differ 2017; 24:1999-2012. [PMID: 28753206 PMCID: PMC5686341 DOI: 10.1038/cdd.2017.118] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 05/15/2017] [Accepted: 06/14/2017] [Indexed: 12/21/2022] Open
Abstract
Rise in plasma free fatty acids (FFAs) represents a major risk factor for obesity-induced type 2 diabetes. Saturated FFAs cause a progressive decline in insulin secretion by promoting pancreatic β-cell death through increased production of reactive oxygen species (ROS). Recent studies have demonstrated that palmitate (a C16-FFA)-induced rise in ROS causes β-cell death by triggering mitochondrial fragmentation, but the underlying mechanisms are unclear. Using the INS1-832/13 β-cell line, here we demonstrate that palmitate generates the ROS required for mitochondrial fission by activating NOX (NADPH oxidase)-2. More importantly, we show that chemical inhibition, RNAi-mediated silencing and knockout of ROS-sensitive TRPM (transient receptor potential melastatin)-2 channels prevent palmitate-induced mitochondrial fission. Although TRPM2 activation affects the intracellular dynamics of Ca2+ and Zn2+, chelation of Zn2+ alone was sufficient to prevent mitochondrial fission. Consistent with the role of Zn2+, palmitate caused a rise in mitochondrial Zn2+, leading to Zn2+-dependent mitochondrial recruitment of Drp-1 (a protein that catalyses mitochondrial fission) and loss of mitochondrial membrane potential. In agreement with the previous reports, Ca2+ caused Drp-1 recruitment, but it failed to induce mitochondrial fission in the absence of Zn2+. These results indicate a novel role for Zn2+ in mitochondrial dynamics. Inhibition or knockout of TRPM2 channels in mouse islets and RNAi-mediated silencing of TRPM2 expression in human islets prevented FFA/cytokine-induced β-cell death, findings that are consistent with the role of abnormal mitochondrial fission in cell death. To conclude, our results reveal a novel, potentially druggable signalling pathway for FFA-induced β-cell death. The cascade involves NOX-2-dependent production of ROS, activation of TRPM2 channels, rise in mitochondrial Zn2+, Drp-1 recruitment and abnormal mitochondrial fission.
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Affiliation(s)
- Fangfang Li
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Tim S Munsey
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Asipu Sivaprasadarao
- Faculty of Biological Sciences, School of Biomedical Sciences, University of Leeds, Leeds LS2 9JT, UK.,Multidisciplinary Cardiovascular Research Centre, University of Leeds, Leeds LS2 9JT, UK
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75
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Thivolet C, Vial G, Cassel R, Rieusset J, Madec AM. Reduction of endoplasmic reticulum- mitochondria interactions in beta cells from patients with type 2 diabetes. PLoS One 2017; 12:e0182027. [PMID: 28742858 PMCID: PMC5526536 DOI: 10.1371/journal.pone.0182027] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Accepted: 07/11/2017] [Indexed: 11/18/2022] Open
Abstract
Type 2 diabetes develops when beta cells are not able to fulfill insulin needs. The role of the endoplasmic reticulum-mitochondria junction in coordinating the functions of these two organelles throughout the natural history of type 2 diabetes is determinant and may explain the alterations of insulin biosynthesis. Our goal was to study endoplasmic reticulum and mitochondrial interactions in human beta cells from organ donors with type 2 diabetes. Pancreas samples were obtained via the network for pancreatic organ donors with diabetes (nPOD) based on disease status with 12 subjects with type 2 diabetes and 9 non-diabetic controls. We examined pancreatic specimens by immunofluorescence, in situ hybridization and in situ proximity ligation assay and compared the results to an in vitro model of beta-cell dysfunction. Expression of proteins that enable tethering and exchanges between endoplasmic reticulum (ER) and mitochondria and quantification of interconnection through mitochondria associated membranes (MAM) was investigated. In beta cells from type 2 diabetic cases as compared to controls, there was a significant increase in reticular expression of inositol triphosphate receptor-2 (IP3R2) both at the protein and mRNA levels, no difference in mitochondrial transit peptide receptor TOM20 and mitofusin-2 expressions, and a decrease in the expression of voltage-dependent anion channel-1 (VDAC-1). The number of IP3R2-VDAC-1 complexes identified by in situ proximity ligation assay was significantly lower in diabetic islets and in beta cells of diabetics as compared to controls. Treatment of Min6-B1 cells with palmitate altered glucose-stimulated insulin secretion, increased ER stress and significantly reduced ER-mitochondrial interactions. We can conclude that specific changes in reticular and mitochondrial beta cell proteins characterize human type 2 diabetes with reduction in organelle interactions. This finding opens new targets of intervention.
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Affiliation(s)
- Charles Thivolet
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
- Hospices Civils de Lyon, Lyon-Sud Hospital, Department of Endocrinology and Diabetes, Pierre-Bénite, France
- * E-mail:
| | - Guillaume Vial
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
| | - Romeo Cassel
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
| | - Jennifer Rieusset
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
| | - Anne-Marie Madec
- INSERM UMR-1060, CarMeN Laboratory, Lyon 1 University, INRA U1235, Lyon, France
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76
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Malenczyk K, Girach F, Szodorai E, Storm P, Segerstolpe Å, Tortoriello G, Schnell R, Mulder J, Romanov RA, Borók E, Piscitelli F, Di Marzo V, Szabó G, Sandberg R, Kubicek S, Lubec G, Hökfelt T, Wagner L, Groop L, Harkany T. A TRPV1-to-secretagogin regulatory axis controls pancreatic β-cell survival by modulating protein turnover. EMBO J 2017; 36:2107-2125. [PMID: 28637794 PMCID: PMC5510001 DOI: 10.15252/embj.201695347] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 04/27/2017] [Accepted: 05/09/2017] [Indexed: 12/20/2022] Open
Abstract
Ca2+-sensor proteins are generally implicated in insulin release through SNARE interactions. Here, secretagogin, whose expression in human pancreatic islets correlates with their insulin content and the incidence of type 2 diabetes, is shown to orchestrate an unexpectedly distinct mechanism. Single-cell RNA-seq reveals retained expression of the TRP family members in β-cells from diabetic donors. Amongst these, pharmacological probing identifies Ca2+-permeable transient receptor potential vanilloid type 1 channels (TRPV1) as potent inducers of secretagogin expression through recruitment of Sp1 transcription factors. Accordingly, agonist stimulation of TRPV1s fails to rescue insulin release from pancreatic islets of glucose intolerant secretagogin knock-out(-/-) mice. However, instead of merely impinging on the SNARE machinery, reduced insulin availability in secretagogin-/- mice is due to β-cell loss, which is underpinned by the collapse of protein folding and deregulation of secretagogin-dependent USP9X deubiquitinase activity. Therefore, and considering the desensitization of TRPV1s in diabetic pancreata, a TRPV1-to-secretagogin regulatory axis seems critical to maintain the structural integrity and signal competence of β-cells.
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Affiliation(s)
- Katarzyna Malenczyk
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Fatima Girach
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Edit Szodorai
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Petter Storm
- Department of Clinical Sciences, Diabetes and Endocrinology CRC, Skåne University Hospital Malmö, Malmö, Sweden
| | - Åsa Segerstolpe
- Integrated Cardio Metabolic Centre, Karolinska Institutet, Huddinge, Sweden
| | | | - Robert Schnell
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Jan Mulder
- Science for Life Laboratory, Karolinska Institutet, Solna, Sweden
| | - Roman A Romanov
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Erzsébet Borók
- Department of Cognitive Neurobiology, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Fabiana Piscitelli
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Pozzuoli Naples, Italy
| | - Vincenzo Di Marzo
- Endocannabinoid Research Group, Istituto di Chimica Biomolecolare, Consiglio Nazionale delle Ricerche, Pozzuoli Naples, Italy
| | - Gábor Szabó
- Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary
| | - Rickard Sandberg
- Integrated Cardio Metabolic Centre, Karolinska Institutet, Huddinge, Sweden
| | - Stefan Kubicek
- CeMM Research Centre for Molecular Medicine, Vienna, Austria
| | - Gert Lubec
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Tomas Hökfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Ludwig Wagner
- University Clinic for Internal Medicine III, General Hospital Vienna, Vienna, Austria
| | - Leif Groop
- Department of Clinical Sciences, Diabetes and Endocrinology CRC, Skåne University Hospital Malmö, Malmö, Sweden
| | - Tibor Harkany
- Department of Molecular Neurosciences, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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77
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Marchetti P, Bugliani M, De Tata V, Suleiman M, Marselli L. Pancreatic Beta Cell Identity in Humans and the Role of Type 2 Diabetes. Front Cell Dev Biol 2017; 5:55. [PMID: 28589121 PMCID: PMC5440564 DOI: 10.3389/fcell.2017.00055] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 05/05/2017] [Indexed: 12/13/2022] Open
Abstract
Pancreatic beta cells uniquely synthetize, store, and release insulin. Specific molecular, functional as well as ultrastructural traits characterize their insulin secretion properties and survival phentoype. In this review we focus on human islet/beta cells, and describe the changes that occur in type 2 diabetes and could play roles in the disease as well as represent possible targets for therapeutical interventions. These include transcription factors, molecules involved in glucose metabolism and insulin granule handling. Quantitative and qualitative insulin release patterns and their changes in type 2 diabetes are also associated with ultrastructural features involving the insulin granules, the mitochondria, and the endoplasmic reticulum.
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Affiliation(s)
- Piero Marchetti
- Department of Clinical and Experimental Medicine, University of PisaPisa, Italy
| | - Marco Bugliani
- Department of Clinical and Experimental Medicine, University of PisaPisa, Italy
| | - Vincenzo De Tata
- Department of Translational Medicine, University of PisaPisa, Italy
| | - Mara Suleiman
- Department of Clinical and Experimental Medicine, University of PisaPisa, Italy
| | - Lorella Marselli
- Department of Clinical and Experimental Medicine, University of PisaPisa, Italy
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78
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Carlbom L, Espes D, Lubberink M, Martinell M, Johansson L, Ahlström H, Carlsson PO, Korsgren O, Eriksson O. [ 11C]5-hydroxy-tryptophan PET for Assessment of Islet Mass During Progression of Type 2 Diabetes. Diabetes 2017; 66:1286-1292. [PMID: 28246291 DOI: 10.2337/db16-1449] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 02/16/2017] [Indexed: 11/13/2022]
Abstract
[11C]5-hydroxy-tryptophan ([11C]5-HTP) positron emission tomography of the pancreas has been shown to be a surrogate imaging biomarker of pancreatic islet mass. The change in islet mass in different stages of type 2 diabetes (T2D) as measured by noninvasive imaging is currently unknown. Here, we describe a cross-sectional study where subjects at different stages of T2D development with expected stratification of pancreatic islet mass were examined in relation to individuals without diabetes. The primary outcome was the [11C]5-HTP uptake and retention in pancreas, as a surrogate marker for the endogenous islet mass. We found that metabolic testing indicated a progressive loss of β-cell function, but this was not mirrored by a decrease in [11C]5-HTP tracer accumulation in the pancreas. This provides evidence of retained islet mass despite decreased β-cell function. The results herein indicate that β-cell dedifferentiation, and not necessarily endocrine cell loss, constitutes a major cause of β-cell failure in T2D.
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Affiliation(s)
- Lina Carlbom
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Daniel Espes
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Mark Lubberink
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Mats Martinell
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Lars Johansson
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
- Antaros Medical AB, Mölndal, Sweden
| | - Håkan Ahlström
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
| | - Per-Ola Carlsson
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Olle Korsgren
- Department of Immunology, Genetics, and Pathology, Uppsala University, Uppsala, Sweden
| | - Olof Eriksson
- Department of Medicinal Chemistry, Uppsala University, Uppsala, Sweden
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79
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Sphingosine kinase 1-interacting protein is a novel regulator of glucose-stimulated insulin secretion. Sci Rep 2017; 7:779. [PMID: 28396589 PMCID: PMC5429731 DOI: 10.1038/s41598-017-00900-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 03/16/2017] [Indexed: 12/12/2022] Open
Abstract
Glucose-stimulated insulin secretion (GSIS) is essential in keeping blood glucose levels within normal range. GSIS is impaired in type 2 diabetes, and its recovery is crucial in treatment of the disease. We find here that sphingosine kinase 1-interacting protein (SKIP, also called Sphkap) is highly expressed in pancreatic β-cells but not in α-cells. Intraperitoneal glucose tolerance test showed that plasma glucose levels were decreased and insulin levels were increased in SKIP−/− mice compared to SKIP+/+ mice, but exendin-4-enhanced insulin secretion was masked. GSIS was amplified more in SKIP−/− but exendin-4-enhanced insulin secretion was masked compared to that in SKIP+/+ islets. The ATP and cAMP content were similarly increased in SKIP+/+ and SKIP−/− islets; depolarization-evoked, PKA and cAMP-mediated insulin secretion were not affected. Inhibition of PDE activity equally augmented GSIS in SKIP+/+ and SKIP−/− islets. These results indicate that SKIP modulates GSIS by a pathway distinct from that of cAMP-, PDE- and sphingosine kinase-dependent pathways.
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80
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Zhu L, Almaça J, Dadi PK, Hong H, Sakamoto W, Rossi M, Lee RJ, Vierra NC, Lu H, Cui Y, McMillin SM, Perry NA, Gurevich VV, Lee A, Kuo B, Leapman RD, Matschinsky FM, Doliba NM, Urs NM, Caron MG, Jacobson DA, Caicedo A, Wess J. β-arrestin-2 is an essential regulator of pancreatic β-cell function under physiological and pathophysiological conditions. Nat Commun 2017; 8:14295. [PMID: 28145434 PMCID: PMC5296650 DOI: 10.1038/ncomms14295] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2016] [Accepted: 12/15/2016] [Indexed: 01/06/2023] Open
Abstract
β-arrestins are critical signalling molecules that regulate many fundamental physiological functions including the maintenance of euglycemia and peripheral insulin sensitivity. Here we show that inactivation of the β-arrestin-2 gene, barr2, in β-cells of adult mice greatly impairs insulin release and glucose tolerance in mice fed with a calorie-rich diet. Both glucose and KCl-induced insulin secretion and calcium responses were profoundly reduced in β-arrestin-2 (barr2) deficient β-cells. In human β-cells, barr2 knockdown abolished glucose-induced insulin secretion. We also show that the presence of barr2 is essential for proper CAMKII function in β-cells. Importantly, overexpression of barr2 in β-cells greatly ameliorates the metabolic deficits displayed by mice consuming a high-fat diet. Thus, our data identify barr2 as an important regulator of β-cell function, which may serve as a new target to improve β-cell function. Beta-arrestins have key roles in development and metabolic functions as euglycaemic control and insulin sentitivity. Here Zhu et al. show that beta-arrestin-2 regulates insulin secretion and glucose tolerance in mice by promoting CAMKII functions in beta cells.
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Affiliation(s)
- Lu Zhu
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Joana Almaça
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida 33136, USA
| | - Prasanna K Dadi
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee 37232, USA
| | - Hao Hong
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA.,Key Laboratory of Acupuncture and Medicine Research of Ministry of Education, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210023, China
| | - Wataru Sakamoto
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Mario Rossi
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Regina J Lee
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Nicholas C Vierra
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee 37232, USA
| | - Huiyan Lu
- Mouse Transgenic Core Facility, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Yinghong Cui
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Sara M McMillin
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
| | - Nicole A Perry
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, USA
| | - Vsevolod V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, Tennessee 37232, USA
| | - Amy Lee
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa 52242, USA
| | - Bryan Kuo
- Laboratory of Bioengineering and Physical Science, National Institute of Biomedical Imaging and Bioengineering, Bethesda, Maryland 20892, USA
| | - Richard D Leapman
- Laboratory of Bioengineering and Physical Science, National Institute of Biomedical Imaging and Bioengineering, Bethesda, Maryland 20892, USA
| | - Franz M Matschinsky
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, Pennslvania 19104, USA
| | - Nicolai M Doliba
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, Pennslvania 19104, USA
| | - Nikhil M Urs
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Marc G Caron
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - David A Jacobson
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee 37232, USA
| | - Alejandro Caicedo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, University of Miami Miller School of Medicine, Miami, Florida 33136, USA
| | - Jürgen Wess
- Molecular Signaling Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, Maryland 20892, USA
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81
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Yoon H, Jeong DK, Lee KS, Kim HS, Moon AE, Park J. Relationship between metabolic syndrome and metabolic syndrome score and beta cell function by gender in Korean populations with obesity. Endocr J 2016; 63:785-793. [PMID: 27350719 DOI: 10.1507/endocrj.ej16-0106] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The present study was conducted to assess the relationships between metabolic syndrome and metabolic syndrome score (MSS) and beta cell function by gender in Korean populations with obesity. This study included 1,686 adults aged 20 or older using the 2010 Korea National Health and Nutrition Examination Survey (KNHANES) data, which represent national data in Korea. The key study results were as follows: First, in men, after adjusting for related variables (including body mass index), metabolic syndrome (p=0.005) and MSS (p=0.018) were inversely associated with the homeostatic model assessment of beta cell function (HOMA-B) values. Second, in women, after adjusting for related variables, metabolic syndrome (p=0.616) and MSS (p=0.929) were not associated with HOMA-B levels. In conclusion, metabolic syndrome and MSS were inversely associated with beta cell function in Korean men with obesity, but not in Korean women with obesity.
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Affiliation(s)
- Hyun Yoon
- Department of Biomedical Laboratory Science, Hanlyo University, Gwangyang-si, Jeollanam-do 57764, South Korea
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82
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Schultz J, Waterstradt R, Kantowski T, Rickmann A, Reinhardt F, Sharoyko V, Mulder H, Tiedge M, Baltrusch S. Precise expression of Fis1 is important for glucose responsiveness of beta cells. J Endocrinol 2016; 230:81-91. [PMID: 27179109 DOI: 10.1530/joe-16-0111] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 05/13/2016] [Indexed: 01/27/2023]
Abstract
Mitochondrial network functionality is vital for glucose-stimulated insulin secretion in pancreatic beta cells. Altered mitochondrial dynamics in pancreatic beta cells are thought to trigger the development of type 2 diabetes mellitus. Fission protein 1 (Fis1) might be a key player in this process. Thus, the aim of this study was to investigate mitochondrial morphology in dependence of beta cell function, after knockdown and overexpression of Fis1. We demonstrate that glucose-unresponsive cells with impaired glucose-stimulated insulin secretion (INS1-832/2) showed decreased mitochondrial dynamics compared with glucose-responsive cells (INS1-832/13). Accordingly, mitochondrial morphology visualised using MitoTracker staining differed between the two cell lines. INS1-832/2 cells formed elongated and clustered mitochondria, whereas INS1-832/13 cells showed a homogenous mitochondrial network. Fis1 overexpression using lentiviral transduction significantly improved glucose-stimulated insulin secretion and mitochondrial network homogeneity in glucose-unresponsive cells. Conversely, Fis1 downregulation by shRNA, both in primary mouse beta cells and glucose-responsive INS1-832/13 cells, caused unresponsiveness and significantly greater numbers of elongated mitochondria. Overexpression of FIS1 in primary mouse beta cells indicated an upper limit at which higher FIS1 expression reduced glucose-stimulated insulin secretion. Thus, FIS1 was overexpressed stepwise up to a high concentration in RINm5F cells using the RheoSwitch system. Moderate FIS1 expression improved glucose-stimulated insulin secretion, whereas high expression resulted in loss of glucose responsiveness and in mitochondrial artificial loop structures and clustering. Our data confirm that FIS1 is a key regulator in pancreatic beta cells, because both glucose-stimulated insulin secretion and mitochondrial dynamics were clearly adapted to precise expression levels of this fission protein.
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Affiliation(s)
- Julia Schultz
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
| | - Rica Waterstradt
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
| | - Tobias Kantowski
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
| | - Annekatrin Rickmann
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
| | - Florian Reinhardt
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
| | - Vladimir Sharoyko
- Department of Clinical SciencesUnit of Molecular Metabolism, Lund University Diabetes Centre, Malmö, Sweden
| | - Hindrik Mulder
- Department of Clinical SciencesUnit of Molecular Metabolism, Lund University Diabetes Centre, Malmö, Sweden
| | - Markus Tiedge
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
| | - Simone Baltrusch
- Institute of Medical Biochemistry and Molecular BiologyUniversity of Rostock, Rostock, Germany
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83
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Yang K, Gotzmann J, Kuny S, Huang H, Sauvé Y, Chan CB. Five stages of progressive β-cell dysfunction in the laboratory Nile rat model of type 2 diabetes. J Endocrinol 2016; 229:343-56. [PMID: 27068697 DOI: 10.1530/joe-15-0517] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 04/11/2016] [Indexed: 02/06/2023]
Abstract
We compared the evolution of insulin resistance, hyperglycemia, and pancreatic β-cell dysfunction in the Nile rat (Arvicanthis niloticus), a diurnal rodent model of spontaneous type 2 diabetes (T2D), when maintained on regular laboratory chow versus a high-fiber diet. Chow-fed Nile rats already displayed symptoms characteristic of insulin resistance at 2 months (increased fat/lean mass ratio and hyperinsulinemia). Hyperglycemia was first detected at 6 months, with increased incidence at 12 months. By this age, pancreatic islet structure was disrupted (increased α-cell area), insulin secretion was impaired (reduced insulin secretion and content) in isolated islets, insulin processing was compromised (accumulation of proinsulin and C-peptide inside islets), and endoplasmic reticulum (ER) chaperone protein ERp44 was upregulated in insulin-producing β-cells. By contrast, high-fiber-fed Nile rats had normoglycemia with compensatory increase in β-cell mass resulting in maintained pancreatic function. Fasting glucose levels were predicted by the α/β-cell ratios. Our results show that Nile rats fed chow recapitulate the five stages of progression of T2D as occurs in human disease, including insulin-resistant hyperglycemia and pancreatic islet β-cell dysfunction associated with ER stress. Modification of diet alone permits long-term β-cell compensation and prevents T2D.
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Affiliation(s)
- Kaiyuan Yang
- Department of AgriculturalFood and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | - Jonathan Gotzmann
- Department of PhysiologyUniversity of Alberta, Edmonton, Alberta, Canada
| | - Sharee Kuny
- Department of Ophthalmology and Visual SciencesUniversity of Alberta, Edmonton, Alberta, Canada
| | - Hui Huang
- Department of PhysiologyUniversity of Alberta, Edmonton, Alberta, Canada
| | - Yves Sauvé
- Department of PhysiologyUniversity of Alberta, Edmonton, Alberta, Canada Department of Ophthalmology and Visual SciencesUniversity of Alberta, Edmonton, Alberta, Canada
| | - Catherine B Chan
- Department of AgriculturalFood and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada Department of PhysiologyUniversity of Alberta, Edmonton, Alberta, Canada
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84
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Do OH, Gunton JE, Gaisano HY, Thorn P. Changes in beta cell function occur in prediabetes and early disease in the Lepr (db) mouse model of diabetes. Diabetologia 2016; 59:1222-30. [PMID: 27048248 PMCID: PMC4869737 DOI: 10.1007/s00125-016-3942-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 02/29/2016] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS Type 2 diabetes is a progressive disease that increases morbidity and the risk of premature death. Glucose dysregulation, such as elevated fasting blood glucose, is observed prior to diabetes onset. A decline in beta cell insulin secretion contributes to the later stages of diabetes, but it is not known what, if any, functional beta cell changes occur in prediabetes and early disease. METHODS The Lepr (db) mouse (age 13-18 weeks) was used as a model of type 2 diabetes and a two-photon granule fusion assay was used to characterise the secretory response of pancreatic beta cells. RESULTS We identified a prediabetic state in db/db mice where the animals responded normally to a glucose challenge but have elevated fasting blood glucose. Isolated islets from prediabetic animals secreted more and were bigger. Insulin secretion, normalised to insulin content, was similar to wild type but basal insulin secretion was elevated. There was increased glucose-induced granule fusion with a high prevalence of granule-granule fusion. The glucose-induced calcium response was not changed but there was altered expression of the exocytic machinery. db/db animals at the next stage of disease had overt glucose intolerance. Isolated islets from these animals had reduced insulin secretion, reduced glucose-induced granule fusion events and decreased calcium responses to glucose. CONCLUSIONS/INTERPRETATION Beta cell function is altered in prediabetes and there are further changes in the progression to early disease.
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Affiliation(s)
- Oanh H Do
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia
- Charles Perkins Centre, University of Sydney, John Hopkins Drive, Camperdown, Sydney, NSW, 2050, Australia
| | - Jenny E Gunton
- Westmead Hospital, Sydney, NSW, 2145, Australia
- Westmead Institute for Medical Research, PO Box 412, Westmead, Sydney, NSW, 2145, Australia
| | - Herbert Y Gaisano
- School of Medicine, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Peter Thorn
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia.
- Charles Perkins Centre, University of Sydney, John Hopkins Drive, Camperdown, Sydney, NSW, 2050, Australia.
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85
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Lyon J, Manning Fox JE, Spigelman AF, Kim R, Smith N, O'Gorman D, Kin T, Shapiro AMJ, Rajotte RV, MacDonald PE. Research-Focused Isolation of Human Islets From Donors With and Without Diabetes at the Alberta Diabetes Institute IsletCore. Endocrinology 2016; 157:560-9. [PMID: 26653569 DOI: 10.1210/en.2015-1562] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Recent years have seen an increased focus on human islet biology, and exciting findings in the stem cell and genomic arenas highlight the need to define the key features of mature human islets and β-cells. Donor and organ procurement parameters impact human islet yield, although for research purposes islet yield may be secondary in importance to islet function. We examined the feasibility of a research-only human islet isolation, distribution, and biobanking program and whether key criteria such as cold ischemia time (CIT) and metabolic status may be relaxed and still allow successful research-focused isolations, including from donors with type 1 diabetes and type 2 diabetes. Through 142 isolations over approximately 5 years, we confirm that CIT and glycated hemoglobin each have a weak negative impacts on isolation purity and yield, and extending CIT beyond the typical clinical isolation cutoff of 12 hours (to ≥ 18 h) had only a modest impact on islet function. Age and glycated hemoglobin/type 2 diabetes status negatively impacted secretory function; however, these and other biological (sex, body mass index) and procurement/isolation variables (CIT, time in culture) appear to make only a small contribution to the heterogeneity of human islet function. This work demonstrates the feasibility of extending acceptable CIT for research-focused human islet isolation and highlights the biological variation in function of human islets from donors with and without diabetes.
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Affiliation(s)
- James Lyon
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Jocelyn E Manning Fox
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Aliya F Spigelman
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Ryekjang Kim
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Nancy Smith
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Doug O'Gorman
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Tatsuya Kin
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - A M James Shapiro
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Raymond V Rajotte
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
| | - Patrick E MacDonald
- Alberta Diabetes Institute IsletCore (J.L., J.E.M.F., P.E.M.) and Departments of Pharmacology (J.E.M.F., A.F.S., R.K., N.S., P.E.M.) and Surgery (D.O., T.K., A.M.J.S., R.V.R.), University of Alberta, Edmonton, Canada T6G 2E1
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86
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Suszynski TM, Avgoustiniatos ES, Papas KK. Oxygenation of the Intraportally Transplanted Pancreatic Islet. J Diabetes Res 2016; 2016:7625947. [PMID: 27872862 PMCID: PMC5107248 DOI: 10.1155/2016/7625947] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 04/27/2016] [Indexed: 12/04/2022] Open
Abstract
Intraportal islet transplantation (IT) is not widely utilized as a treatment for type 1 diabetes. Oxygenation of the intraportally transplanted islet has not been studied extensively. We present a diffusion-reaction model that predicts the presence of an anoxic core and a larger partly functional core within intraportally transplanted islets. Four variables were studied: islet diameter, islet fractional viability, external oxygen partial pressure (P) (in surrounding portal blood), and presence or absence of a thrombus on the islet surface. Results indicate that an islet with average size and fractional viability exhibits an anoxic volume fraction (AVF) of 14% and a function loss of 72% at a low external P. Thrombus formation increased AVF to 30% and function loss to 92%, suggesting that the effect of thrombosis may be substantial. External P and islet diameter accounted for the greatest overall impact on AVF and loss of function. At our institutions, large human alloislets (>200 μm diameter) account for ~20% of total islet number but ~70% of total islet volume; since most of the total transplanted islet volume is accounted for by large islets, most of the intraportal islet cells are likely to be anoxic and not fully functional.
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Affiliation(s)
| | | | - Klearchos K. Papas
- Department of Surgery, University of Minnesota, Minneapolis, MN 55455, USA
- Institute for Cellular Transplantation, Department of Surgery, University of Arizona, Tucson, AZ 85724, USA
- *Klearchos K. Papas:
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87
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Hoang Do O, Thorn P. Insulin secretion from beta cells within intact islets: location matters. Clin Exp Pharmacol Physiol 2015; 42:406-14. [PMID: 25676261 PMCID: PMC4418378 DOI: 10.1111/1440-1681.12368] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 12/21/2014] [Accepted: 01/06/2015] [Indexed: 12/17/2022]
Abstract
The control of hormone secretion is central to body homeostasis, and its dysfunction is important in many diseases. The key cellular steps that lead to hormone secretion have been identified, and the stimulus-secretion pathway is understood in outline for many endocrine cells. In the case of insulin secretion from pancreatic beta cells, this pathway involves the uptake of glucose, cell depolarization, calcium entry, and the triggering of the fusion of insulin-containing granules with the cell membrane. The wealth of information on the control of insulin secretion has largely been obtained from isolated single-cell studies. However, physiologically, beta cells exist within the islets of Langerhans, with structural and functional specializations that are not preserved in single-cell cultures. This review focuses on recent work that is revealing distinct aspects of insulin secretion from beta cells within the islet.
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Affiliation(s)
- Oanh Hoang Do
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, Qld, Australia
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88
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Angptl4 links α-cell proliferation following glucagon receptor inhibition with adipose tissue triglyceride metabolism. Proc Natl Acad Sci U S A 2015; 112:15498-503. [PMID: 26621734 DOI: 10.1073/pnas.1513872112] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Type 2 diabetes is characterized by a reduction in insulin function and an increase in glucagon activity that together result in hyperglycemia. Glucagon receptor antagonists have been developed as drugs for diabetes; however, they often increase glucagon plasma levels and induce the proliferation of glucagon-secreting α-cells. We find that the secreted protein Angiopoietin-like 4 (Angptl4) is up-regulated via Pparγ activation in white adipose tissue and plasma following an acute treatment with a glucagon receptor antagonist. Induction of adipose angptl4 and Angptl4 supplementation promote α-cell proliferation specifically. Finally, glucagon receptor antagonist improves glycemia in diet-induced obese angptl4 knockout mice without increasing glucagon levels or α-cell proliferation, underscoring the importance of this protein. Overall, we demonstrate that triglyceride metabolism in adipose tissue regulates α-cells in the endocrine pancreas.
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89
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Doliba NM, Liu Q, Li C, Chen J, Chen P, Liu C, Frederick DW, Baur JA, Bennett MJ, Naji A, Matschinsky FM. Accumulation of 3-hydroxytetradecenoic acid: Cause or corollary of glucolipotoxic impairment of pancreatic β-cell bioenergetics? Mol Metab 2015; 4:926-39. [PMID: 26909309 PMCID: PMC4731732 DOI: 10.1016/j.molmet.2015.09.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Revised: 09/16/2015] [Accepted: 09/25/2015] [Indexed: 12/20/2022] Open
Abstract
Objectives Hyperglycemia and elevated blood lipids are the presumed precipitating causes of β-cell damage in T2DM as the result of a process termed “glucolipotoxicity”. Here, we tested whether glucolipotoxic pathophysiology is caused by defective bioenergetics using islets in culture. Methods Insulin secretion, respiration, ATP generation, fatty acid (FA) metabolite profiles and gene expression were determined in isolated islets treated under glucolipotoxic culture conditions. Results Over time, chronic exposure of mouse islets to FAs with glucose leads to bioenergetic failure and reduced insulin secretion upon stimulation with glucose or amino acids. Islets exposed to glucolipotoxic conditions displayed biphasic changes of the oxygen consumption rate (OCR): an initial increase in baseline and Vmax of OCR after 3 days, followed by decreased baseline and glucose stimulated OCR after 5 days. These changes were associated with lower islet ATP levels, impaired glucose-induced ATP generation, a trend for reduced mitochondrial DNA content and reduced expression of mitochondrial transcription factor A (Tfam). We discovered the accumulation of carnitine esters of hydroxylated long chain FAs, in particular 3-hydroxytetradecenoyl-carnitine. Conclusions As long chain 3-hydroxylated FA metabolites are known to uncouple heart and brain mitochondria [53], [54], [55], we propose that under glucolipotoxic condition, unsaturated hydroxylated long-chain FAs accumulate, uncouple and ultimately inhibit β-cell respiration. This leads to the slow deterioration of mitochondrial function progressing to bioenergetics β-cell failure. We found low capacity of islets to generate ATP after glucolipotoxic treatment. Found biphasic (up/down) respiratory time course as expression of glucolipotoxicity. We found β-Hydroxylated long FA metabolites as new glucolipotoxicity mediators. β-Hydroxylated long FAs are known to uncouple Ox/Phos. We propose defective bioenergetics as main cause of glucolipotoxicity.
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Affiliation(s)
- Nicolai M. Doliba
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
- Corresponding author. University of Pennsylvania, Biochemistry/Biophysics, 3400 Civic Center Blvd, Smilow Center for Translation Research, TRC12-131, Philadelphia, PA 19104, United States. Tel.: +1 215 898 4366; fax: +1 215 898 5408.
| | - Qing Liu
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
| | - Changhong Li
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
- Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Jie Chen
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Pan Chen
- Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Chengyang Liu
- Department of Surgery, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
| | - David W. Frederick
- Department of Physiology, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
| | - Joseph A. Baur
- Department of Physiology, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
| | - Michael J. Bennett
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Ali Naji
- Department of Surgery, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
| | - Franz M. Matschinsky
- Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, United States
- Institute for Diabetes, Obesity and Metabolism, University of Pennsylvania School of Medicine, United States
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90
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Striegel DA, Hara M, Periwal V. The Beta Cell in Its Cluster: Stochastic Graphs of Beta Cell Connectivity in the Islets of Langerhans. PLoS Comput Biol 2015; 11:e1004423. [PMID: 26266953 PMCID: PMC4534467 DOI: 10.1371/journal.pcbi.1004423] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 07/02/2015] [Indexed: 12/25/2022] Open
Abstract
Pancreatic islets of Langerhans consist of endocrine cells, primarily α, β and δ cells, which secrete glucagon, insulin, and somatostatin, respectively, to regulate plasma glucose. β cells form irregular locally connected clusters within islets that act in concert to secrete insulin upon glucose stimulation. Due to the central functional significance of this local connectivity in the placement of β cells in an islet, it is important to characterize it quantitatively. However, quantification of the seemingly stochastic cytoarchitecture of β cells in an islet requires mathematical methods that can capture topological connectivity in the entire β-cell population in an islet. Graph theory provides such a framework. Using large-scale imaging data for thousands of islets containing hundreds of thousands of cells in human organ donor pancreata, we show that quantitative graph characteristics differ between control and type 2 diabetic islets. Further insight into the processes that shape and maintain this architecture is obtained by formulating a stochastic theory of β-cell rearrangement in whole islets, just as the normal equilibrium distribution of the Ornstein-Uhlenbeck process can be viewed as the result of the interplay between a random walk and a linear restoring force. Requiring that rearrangements maintain the observed quantitative topological graph characteristics strongly constrained possible processes. Our results suggest that β-cell rearrangement is dependent on its connectivity in order to maintain an optimal cluster size in both normal and T2D islets. High or low blood glucose levels are detrimental to human health. The hormone-secreting cells primarily responsible for maintaining glucose at physiologically appropriate levels are embedded in small clusters within the pancreas, the so-called islets of Langerhans. These islets have an irregular arrangement of cells, β cells that secrete insulin, α cells that secrete glucagon, and other cells with less well-understood functions. While the arrangement of β cells is irregular, these cells need to be touching for the islet to respond to glucose with insulin secretion. We first use a mathematical formalism called graph theory to show that cell arrangements in islets from diabetic and control donors are significantly different. The question we then address is: Is there some set of moves of islet cells that will preserve the observed arrangement? The aim is to gain insight into the biological processes by which islets are formed and maintained. We find moves on β-cell graphs that leave the same significant aspects of cell arrangements unchanged. These moves turn out to be severely restricted, and suggest that β cells may prefer to move from larger clusters but can move to a cluster of any size, possibly to maximize their exposure to blood vessels.
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Affiliation(s)
- Deborah A. Striegel
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Manami Hara
- Department of Medicine, University of Chicago, Chicago, Illinois, United States of America
| | - Vipul Periwal
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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91
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Spijker HS, Song H, Ellenbroek JH, Roefs MM, Engelse MA, Bos E, Koster AJ, Rabelink TJ, Hansen BC, Clark A, Carlotti F, de Koning EJP. Loss of β-Cell Identity Occurs in Type 2 Diabetes and Is Associated With Islet Amyloid Deposits. Diabetes 2015; 64:2928-38. [PMID: 25918235 DOI: 10.2337/db14-1752] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 04/10/2015] [Indexed: 01/06/2023]
Abstract
Loss of pancreatic islet β-cell mass and β-cell dysfunction are central in the development of type 2 diabetes (T2DM). We recently showed that mature human insulin-containing β-cells can convert into glucagon-containing α-cells ex vivo. This loss of β-cell identity was characterized by the presence of β-cell transcription factors (Nkx6.1, Pdx1) in glucagon(+) cells. Here, we investigated whether the loss of β-cell identity also occurs in vivo, and whether it is related to the presence of (pre)diabetes in humans and nonhuman primates. We observed an eight times increased frequency of insulin(+) cells coexpressing glucagon in donors with diabetes. Up to 5% of the cells that were Nkx6.1(+) but insulin(-) coexpressed glucagon, which represents a five times increased frequency compared with the control group. This increase in bihormonal and Nkx6.1(+)glucagon(+)insulin(-) cells was also found in islets of diabetic macaques. The higher proportion of bihormonal cells and Nkx6.1(+)glucagon(+)insulin(-) cells in macaques and humans with diabetes was correlated with the presence and extent of islet amyloidosis. These data indicate that the loss of β-cell identity occurs in T2DM and could contribute to the decrease of functional β-cell mass. Maintenance of β-cell identity is a potential novel strategy to preserve β-cell function in diabetes.
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Affiliation(s)
- H Siebe Spijker
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Heein Song
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Johanne H Ellenbroek
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Maaike M Roefs
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Marten A Engelse
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Erik Bos
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Abraham J Koster
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, the Netherlands
| | - Ton J Rabelink
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Barbara C Hansen
- Departments of Internal Medicine and Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Anne Clark
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Churchill Hospital, Oxford, U.K
| | - Françoise Carlotti
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands
| | - Eelco J P de Koning
- Department of Nephrology, Leiden University Medical Center, Leiden, the Netherlands Hubrecht Institute, Utrecht, the Netherlands
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92
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Hydrolysis enhances bioavailability of proanthocyanidin-derived metabolites and improves β-cell function in glucose intolerant rats. J Nutr Biochem 2015; 26:850-9. [DOI: 10.1016/j.jnutbio.2015.03.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 03/01/2015] [Accepted: 03/10/2015] [Indexed: 11/24/2022]
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93
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DeFronzo RA, Ferrannini E, Groop L, Henry RR, Herman WH, Holst JJ, Hu FB, Kahn CR, Raz I, Shulman GI, Simonson DC, Testa MA, Weiss R. Type 2 diabetes mellitus. Nat Rev Dis Primers 2015; 1:15019. [PMID: 27189025 DOI: 10.1038/nrdp.2015.19] [Citation(s) in RCA: 1037] [Impact Index Per Article: 115.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Type 2 diabetes mellitus (T2DM) is an expanding global health problem, closely linked to the epidemic of obesity. Individuals with T2DM are at high risk for both microvascular complications (including retinopathy, nephropathy and neuropathy) and macrovascular complications (such as cardiovascular comorbidities), owing to hyperglycaemia and individual components of the insulin resistance (metabolic) syndrome. Environmental factors (for example, obesity, an unhealthy diet and physical inactivity) and genetic factors contribute to the multiple pathophysiological disturbances that are responsible for impaired glucose homeostasis in T2DM. Insulin resistance and impaired insulin secretion remain the core defects in T2DM, but at least six other pathophysiological abnormalities contribute to the dysregulation of glucose metabolism. The multiple pathogenetic disturbances present in T2DM dictate that multiple antidiabetic agents, used in combination, will be required to maintain normoglycaemia. The treatment must not only be effective and safe but also improve the quality of life. Several novel medications are in development, but the greatest need is for agents that enhance insulin sensitivity, halt the progressive pancreatic β-cell failure that is characteristic of T2DM and prevent or reverse the microvascular complications. For an illustrated summary of this Primer, visit: http://go.nature.com/V2eGfN.
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Affiliation(s)
- Ralph A DeFronzo
- Diabetes Division, Department of Medicine, University of Texas Health Science Center, South Texas Veterans Health Care System and Texas Diabetes Institute, 701 S. Zarzamoro, San Antonio, Texas 78207, USA
| | | | - Leif Groop
- Department of Clinical Science Malmoe, Diabetes &Endocrinology, Lund University Diabetes Centre, Lund, Sweden
| | - Robert R Henry
- University of California, San Diego, Section of Diabetes, Endocrinology &Metabolism, Center for Metabolic Research, VA San Diego Healthcare System, San Diego, California, USA
| | | | | | - Frank B Hu
- Department of Nutrition, Harvard T.H. Chan School of Public Health and Department of Epidemiology, Harvard T.H. Chan School of Public Health and Channing Division of Network Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - C Ronald Kahn
- Harvard Medical School and Joslin Diabetes Center, Boston, Massachusetts, USA
| | - Itamar Raz
- Diabetes Unit, Division of Internal Medicine, Hadassah Hebrew University Hospital, Jerusalem, Israel
| | - Gerald I Shulman
- Howard Hughes Medical Institute and the Departments of Internal Medicine and Cellular &Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Donald C Simonson
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Marcia A Testa
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Ram Weiss
- Department of Human Metabolism and Nutrition, Braun School of Public Health, Hebrew University, Jerusalem, Israel
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94
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Mohan R, Mao Y, Zhang S, Zhang YW, Xu CR, Gradwohl G, Tang X. Differentially Expressed MicroRNA-483 Confers Distinct Functions in Pancreatic β- and α-Cells. J Biol Chem 2015; 290:19955-66. [PMID: 26109062 DOI: 10.1074/jbc.m115.650705] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Indexed: 01/08/2023] Open
Abstract
Insulin secreted from pancreatic β-cells and glucagon secreted from pancreatic α-cells are the two major hormones working in the pancreas in an opposing manner to regulate and maintain a normal glucose homeostasis. How microRNAs (miRNAs), a population of non-coding RNAs so far demonstrated to be differentially expressed in various types of cells, regulate gene expression in pancreatic β-cells and its closely associated α-cells is not completely clear. In this study, miRNA profiling was performed and compared between pancreatic β-cells and their partner α-cells. One novel miRNA, miR-483, was identified for its highly differential expression in pancreatic β-cells when compared to its expression in α-cells. Overexpression of miR-483 in β-cells increased insulin transcription and secretion by targeting SOCS3, a member of suppressor of cytokine signaling family. In contrast, overexpression of miR-483 decreased glucagon transcription and secretion in α-cells. Moreover, overexpressed miR-483 protected against proinflammatory cytokine-induced apoptosis in β-cells. This correlates with a higher expression level of miR-483 and the expanded β-cell mass observed in the islets of prediabetic db/db mice. Together, our data suggest that miR-483 has opposite effects in α- and β-cells by targeting SOCS3, and the imbalance of miR-483 and its targets may play a crucial role in diabetes pathogenesis.
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Affiliation(s)
- Ramkumar Mohan
- From the Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931
| | - Yiping Mao
- From the Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931
| | - Shungang Zhang
- From the Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931
| | - Yu-Wei Zhang
- the College of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and
| | - Cheng-Ran Xu
- the College of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing 100871, China, and
| | - Gérard Gradwohl
- the Institute of Genetics and Molecular and Cellular Biology, Department of Development and Stem cells, University of Strasbourg, 67404 Illkirch, France
| | - Xiaoqing Tang
- From the Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931,
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95
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Hashemitabar M, Bahramzadeh S, Saremy S, Nejaddehbashi F. Glucose plus metformin compared with glucose alone on β-cell function in mouse pancreatic islets. Biomed Rep 2015; 3:721-725. [PMID: 26405552 DOI: 10.3892/br.2015.476] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 04/24/2015] [Indexed: 12/19/2022] Open
Abstract
Metformin is currently the first drug of choice for treatment of type II diabetes. The primary function of metformin is to decrease hepatic glucose production mainly by inhibiting gluconeogenesis. The aim of the present study was to investigate the effects of glucose alone (control groups) and glucose and metformin (treatment groups) on pancreatic islets functions. Pancreatic islets were isolated by collagenase digestion and incubated for 24 or 48 h in RPMI-1640 containing 5 mmol/l glucose (control groups 1 and 2, respectively) or 24 h with 25 mmol/l glucose (control group 3) and 15 µmol/l metformin (treatment groups 1, 2 and 3, corresponding to the control groups, respectively). Subsequently, the rate of insulin output from islets, pancreatic and duodenal homeobox 1 (Pdx-1) and insulin genes expression and islet viability were assayed. The rate of insulin secretion in a 5 mmol/l glucose concentration in the 48 h treatment group increased significantly compared with that of the 24 h treatment group (P<0.05). An increase of the glucose concentration (25 mmol/l) caused insulin secretion to increase compared with that of 5 mmol/l glucose. Pdx-1 gene expression in treatment group 2 significantly decreased compared with the control group 2 (P<0.05). The the Pdx-1 gene expression in treatment group 2 decreased compared with that of the treatment group 1. The expression of the insulin gene in treatment group 1 increased compared with control group 1, and in treatment group 2, there was a 2-fold increase in insulin gene expression compared with control group 2. The insulin gene expression in treatment group 2 increased compared with treatment group 1. The percentage of islet cell viability was increased in treatment group 3 by ~40% compared with the islet cells of treatment groups 1 and 2 (P<0/05). These data indicate that glucose and metformin have direct effects on β-cell function.
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Affiliation(s)
- Mahmoud Hashemitabar
- Cellular and Molecular Research Center, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan 61357-15794, Iran
| | - Somayeh Bahramzadeh
- Cellular and Molecular Research Center, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan 61357-15794, Iran
| | - Sadegh Saremy
- Cellular and Molecular Research Center, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan 61357-15794, Iran
| | - Freshteh Nejaddehbashi
- Cellular and Molecular Research Center, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Khuzestan 61357-15794, Iran
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96
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Cantley J, Ashcroft FM. Q&A: insulin secretion and type 2 diabetes: why do β-cells fail? BMC Biol 2015; 13:33. [PMID: 25982967 PMCID: PMC4435650 DOI: 10.1186/s12915-015-0140-6] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 04/17/2015] [Indexed: 12/11/2022] Open
Affiliation(s)
- James Cantley
- Department of Physiology, Anatomy & Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK
| | - Frances M Ashcroft
- Department of Physiology, Anatomy & Genetics, University of Oxford, Parks Road, Oxford, OX1 3PT, UK.
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97
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Kokil GR, Veedu RN, Ramm GA, Prins JB, Parekh HS. Type 2 diabetes mellitus: limitations of conventional therapies and intervention with nucleic acid-based therapeutics. Chem Rev 2015; 115:4719-43. [PMID: 25918949 DOI: 10.1021/cr5002832] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Ganesh R Kokil
- †School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Brisbane, QLD 4102, Australia
| | - Rakesh N Veedu
- §Center for Comparative Genomics, Murdoch University, 90 South Street, Murdoch, WA 6150, Australia.,∥Western Australian Neuroscience Research Institute, Perth, WA 6150, Australia.,‡School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane QLD 4072 Australia
| | - Grant A Ramm
- ⊥The Hepatic Fibrosis Group, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia.,#Faculty of Medicine and Biomedical Sciences, The University of Queensland, Brisbane, QLD 4006, Australia
| | - Johannes B Prins
- ∇Mater Research Institute, The University of Queensland, Brisbane, QLD 4101, Australia
| | - Harendra S Parekh
- †School of Pharmacy, Pharmacy Australia Centre of Excellence, The University of Queensland, Brisbane, QLD 4102, Australia
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98
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Qi M, Luis V, Bilbao S, Omori K, Rawson J, McFadden B, Juan J, Nair I, Mullen Y, El-Shahawy M, Dafoe D, Kandeel F, Al-Abdullah IH. Sodium levels of human pancreatic donors are a critical factor for determination of islet efficacy and survival. Am J Physiol Endocrinol Metab 2015; 308:E362-9. [PMID: 25537495 DOI: 10.1152/ajpendo.00443.2014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Organs from hypernatremia (elevated Na+) donors when used for transplantation have had dismal outcomes. However, islet isolation from hypernatremic donors for both transplantation and research applications has not yet been investigated. A retrospective analysis of in vivo and in vitro islet function studies was performed on islets isolated from hypernatremic (serum sodium levels≥160 meq/l) and normal control (serum sodium levels≤155 meq/l) donors. Twelve isolations from 32 hypernatremic and 53 isolations from 222 normal donors were randomly transplanted into diabetic NOD Scid mice. Sodium levels upon pancreas procurement were significantly elevated in the hypernatremia group (163.5±0.6 meq/l) compared with the normal control group (145.9±0.4 meq/l) (P<0.001). The postculture islet recovery rate was significantly lower in the hypernatremia (59.1±3.8%) group compared with the normal (73.6±1.8%) group (P=0.005). The duration of hypernatremia was inversely correlated with the recovery rate (r2=0.370, P<0.001). Furthermore, the percentage of successful graft function when transplanted into diabetic NOD Scid mice was significantly lower in the hypernatremia (42%) group compared with the normal control (85%) group (P<0.001). The ability to predict islet graft function posttransplantation using donor sodium levels and duration of hypernatremia was significant (ROC analysis, P=0.022 and 0.042, respectively). In conclusion, duration of donor hypernatremia is associated with reduced islet recovery postculture. The efficacy of islets from hypernatremia donors diminished when transplanted into diabetic recipients.
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Affiliation(s)
- Meirigeng Qi
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Valiente Luis
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Shiela Bilbao
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Keiko Omori
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Jeffrey Rawson
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Brian McFadden
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Jemily Juan
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Indu Nair
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Yoko Mullen
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Mohamed El-Shahawy
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Donald Dafoe
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Fouad Kandeel
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
| | - Ismail H Al-Abdullah
- Department of Diabetes and Metabolic Diseases Research, Beckman Research Institute of the City of Hope, Duarte, California
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99
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Abstract
Both pancreas and islet transplantations are therapeutic options for complicated type 1 diabetes. Until recent years, outcomes of islet transplantation have been significantly inferior to those of whole pancreas. Islet transplantation is primarily performed alone in patients with severe hypoglycemia, and recent registry reports have suggested that results of islet transplantation alone in this indication may be about to match those of pancreas transplant alone in insulin independence. Figures of 50% insulin independence at 5 years for either procedure have been cited. In this article, we address the question whether islet transplantation has indeed bridged the gap with whole pancreas. Looking at the evidence to answer this question, we propose that although pancreas may still be more efficient in taking recipients off insulin than islets, there are in fact numerous "gaps" separating both procedures that must be taken into the equation. These "gaps" relate to organ utilization, organ allocation, indication for transplantation, and morbidity. In-depth analysis reveals that islet transplantation, in fact, has an edge on whole pancreas in some of these aspects. Accordingly, attempts should be made to bridge these gaps from both sides to achieve the same level of success with either procedure. More realistically, it is likely that some of these gaps will remain and that both procedures will coexist and complement each other, to ensure that β cell replacement can be successfully implemented in the greatest possible number of patients with type 1 diabetes.
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100
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Mitchell RK, Mondragon A, Chen L, Mcginty JA, French PM, Ferrer J, Thorens B, Hodson DJ, Rutter GA, Da Silva Xavier G. Selective disruption of Tcf7l2 in the pancreatic β cell impairs secretory function and lowers β cell mass. Hum Mol Genet 2014; 24:1390-9. [PMID: 25355422 PMCID: PMC4321446 DOI: 10.1093/hmg/ddu553] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Type 2 diabetes (T2D) is characterized by β cell dysfunction and loss. Single nucleotide polymorphisms in the T-cell factor 7-like 2 (TCF7L2) gene, associated with T2D by genome-wide association studies, lead to impaired β cell function. While deletion of the homologous murine Tcf7l2 gene throughout the developing pancreas leads to impaired glucose tolerance, deletion in the β cell in adult mice reportedly has more modest effects. To inactivate Tcf7l2 highly selectively in β cells from the earliest expression of the Ins1 gene (∼E11.5) we have therefore used a Cre recombinase introduced at the Ins1 locus. Tcfl2fl/fl::Ins1Cre mice display impaired oral and intraperitoneal glucose tolerance by 8 and 16 weeks, respectively, and defective responses to the GLP-1 analogue liraglutide at 8 weeks. Tcfl2fl/fl::Ins1Cre islets displayed defective glucose- and GLP-1-stimulated insulin secretion and the expression of both the Ins2 (∼20%) and Glp1r (∼40%) genes were significantly reduced. Glucose- and GLP-1-induced intracellular free Ca2+ increases, and connectivity between individual β cells, were both lowered by Tcf7l2 deletion in islets from mice maintained on a high (60%) fat diet. Finally, analysis by optical projection tomography revealed ∼30% decrease in β cell mass in pancreata from Tcfl2fl/fl::Ins1Cre mice. These data demonstrate that Tcf7l2 plays a cell autonomous role in the control of β cell function and mass, serving as an important regulator of gene expression and islet cell coordination. The possible relevance of these findings for the action of TCF7L2 polymorphisms associated with Type 2 diabetes in man is discussed.
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Affiliation(s)
- Ryan K Mitchell
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine
| | - Angeles Mondragon
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine
| | | | | | | | - Jorge Ferrer
- Section of Genetics and Medicine, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Imperial College London, London, UK
| | - Bernard Thorens
- Center for Integrative Genomics, Physiology Department, University of Lausanne, Genopode Building, CH-1015 Lausanne, Switzerland
| | - David J Hodson
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine
| | - Guy A Rutter
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine,
| | - Gabriela Da Silva Xavier
- Section of Cell Biology, Division of Diabetes, Endocrinology and Metabolism, Department of Medicine,
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