1
|
Shah P, Lueschen N, Ardestani A, Oberholzer J, Olerud J, Carlsson PO, Maedler K. Correction: Angiopoetin-2 Signals Do Not Mediate the Hypervascularization of Islets in Type 2 Diabetes. PLoS One 2023; 18:e0282771. [PMID: 36862649 PMCID: PMC9980724 DOI: 10.1371/journal.pone.0282771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
Abstract
[This corrects the article DOI: 10.1371/journal.pone.0161834.].
Collapse
|
2
|
Apolipoprotein A-I primes beta cells to increase glucose stimulated insulin secretion. Biochim Biophys Acta Mol Basis Dis 2019; 1866:165613. [PMID: 31765698 DOI: 10.1016/j.bbadis.2019.165613] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 10/17/2019] [Accepted: 11/05/2019] [Indexed: 01/01/2023]
Abstract
The increase of plasma levels of high-density lipoproteins and Apolipoprotein A-I (ApoA-I), its main protein component, has been shown to have a positive action on glucose disposal in type 2 diabetic patients. The current study investigates the unexplored function of ApoA-I to prime beta cells for improved insulin secretion. INS-1E rat clonal beta cells as well as isolated murine islets were used to study the effect of ApoA-I on responsiveness of the beta cells to high glucose challenge. Confocal and transmission electron microscopy were used to dissect ApoA-I mechanisms of action. Chemical endocytosis blockers were used to understand the role of ApoA-I internalization in mediating its positive effect. Pre-incubation of beta cells and isolated murine islets with ApoA-I augmented glucose stimulated insulin secretion. This effect appeared to be due to an increased reservoir of insulin granules at the cell membrane, as confirmed by confocal and transmission electron microscopy. Moreover, ApoA-I induced pancreatic and duodenal homeobox 1 (PDX1) shuttling from the cytoplasm to the nucleus, with the subsequent increase in the proinsulin processing enzyme protein convertase 1 (PC1/3). Finally, the blockade of ApoA-I endocytosis in beta cells resulted in a loss of ApoA-I positive action on insulin secretion. The proposed mechanisms of the phenomenon here described include ApoA-I internalization into beta cells, PDX1 nuclear translocation, and increased levels of proinsulin processing enzymes. Altogether, these events lead to an increased number of insulin granules.
Collapse
|
3
|
Argun-Kurum G, Kaya-Dagistanli F, Ozturk M. DPP4 inhibitor induces beta cell regeneration and DDR-1 protein expression as an endocrine progenitor cell marker in neonatal STZ-diabetic rats. Pharmacol Rep 2019; 71:721-731. [PMID: 31207434 DOI: 10.1016/j.pharep.2019.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 02/25/2019] [Accepted: 03/14/2019] [Indexed: 12/25/2022]
Abstract
BACKGROUND We aim to investigate the effects of dipeptidyl-peptidase-4 inhibitor (Vildagliptin-VG) on DDR-1 as a marker for endocrine progenitor cells, β-cell regeneration, and apoptosis in neonatal streptozotocin (n2-STZ) diabetics. METHODS Neonatal rats were divided into two main groups as short- and long-term treatment, each consisted of four groups; (1) Control, (2) n2-STZ diabetic (single dose of 100 mg/kg STZ at 2nd day of birth), (3) n2-STZ + VG (60 mg/kg/day VG orally; for 8 and 28 days), (4) VG (60 mg/kg/day orally; for 8 and 28 days). Blood glucose levels and body weights were measured, and the tissue sections were immunostained using insulin, glucagon, somatostatin, PCNA, Pdx-1 and DDR-1 antibodies. The TUNEL method was used for apoptosis. RESULTS The number of β cells in islets of the n2-STZ + VG group increased compared to the n2-STZ group; insulin (+) cells were observed individually or as small clusters in exocrine tissue, between pancreatic duct epithelial cells, and around the ducts. The number of Pdx-1 and DDR-1 positive cells in islet and extra-islet pancreas tissue was elevated as a result of VG application compared to the STZ diabetic group; the number of double positive cells for DDR-1 and insulin increased in n2-STZ + VG rats. CONCLUSION We showed that vildagliptin promotes β cell neogenesis and regeneration, stimulates DDR-1 expression as an endocrine cell progenitor marker, suppresses apoptosis, induces islet cell proliferation and rearranges islet morphology in the n2-STZ diabetes model.
Collapse
Affiliation(s)
- Gamze Argun-Kurum
- Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty, Department of Medical Biology, Istanbul, Turkey
| | - Fatma Kaya-Dagistanli
- Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty, Department of Medical Biology, Istanbul, Turkey
| | - Melek Ozturk
- Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty, Department of Medical Biology, Istanbul, Turkey.
| |
Collapse
|
4
|
Update to Expression of Concern. Kathrin Maedler, Desiree M. Schumann, Nadine Sauter, Helga Ellingsgaard, Domenico Bosco, Reto Baertschiger, Yoichiro Iwakura, José Oberholzer, Claes B. Wollheim, Benoit R. Gauthier, and Marc Y. Donath. Low Concentration of Interleukin-1β Induces FLICE-Inhibitory Protein-Mediated β-Cell Proliferation in Human Pancreatic Islets. Diabetes 2006;55:2713-2722. DOI:10.2337/db05-1430. PMID: 17003335. Diabetes 2018; 67:2479-2480. [PMID: 30213822 PMCID: PMC6198340 DOI: 10.2337/db18-ec2018b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
|
5
|
Expression of Concern. Kathrin Maedler, Desiree M. Schumann, Fabienne Schulthess, José Oberholzer, Domenico Bosco, Thierry Berney, and Marc Y. Donath. Aging Correlates With Decreased β-Cell Proliferative Capacity and Enhanced Sensitivity to Apoptosis: A Potential Role for Fas and Pancreatic Duodenal Homeobox-1. Diabetes 2006;55:2455-2462. DOI: 10.2337/db05-1586. PMID: 16936193. Diabetes 2018; 67:2478-2479. [PMID: 30213821 PMCID: PMC6198338 DOI: 10.2337/db18-ec2018a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
6
|
Gallego FQ, Sinzato YK, Miranda CA, Iessi IL, Dallaqua B, Volpato GT, Scarano WR, SanMartín S, Damasceno DC. Pancreatic islet response to diabetes during pregnancy in rats. Life Sci 2018; 214:1-10. [PMID: 30366036 DOI: 10.1016/j.lfs.2018.10.046] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 10/21/2018] [Accepted: 10/22/2018] [Indexed: 12/31/2022]
Abstract
AIMS The objective of this study was to assess the mechanisms underlying pancreatic islet adaptation in diabetic mothers and their pups. Additionally, the influence of pancreatic adaptations on maternal reproductive performance was also investigated. MAIN METHODS Wistar rats were injected with streptozotocin for diabetes induction. At adulthood (3 months), all animals underwent an oral glucose tolerance test (OGTT) for glucose assessment as an inclusion criterion. Following, the animals were mated. At day 18 of pregnancy, the mothers were killed for blood collect ion to determine fasting insulin and glucagon concentrations. The pancreas was removed and processed for the immunohistochemical analysis of insulin, glucagon, somatostatin, Ki-67 and PDX-1, superoxide dismutase 1 (SOD-1), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA). The pregnant uterus was also collected for the evaluation of embryofetal loss. KEY FINDINGS The diabetic rats showed increased glucose, serum glucagon and insulin concentrations, and embryofetal loss rates. They also showed a reduction in pancreatic islets area and percentage of cells stained for insulin, increased the percentage of non-β cells (alpha e delta cells) stained for Ki-67, glucagon, and somatostatin. Moreover, the cells stained for somatostatin were spread across the islets and showed stronger staining for MDA and weaker staining for GSH-Px. SIGNIFICANCE Diabetes leads to adaptive responses from the endocrine pancreas in pregnancy that especially involves non-β cells, modifying the mantle-core structure. Nonetheless, these adaptations are not enough for glucose homeostasis and affect the maternal environment, which in turn impairs fetal development.
Collapse
Affiliation(s)
- Franciane Quintanilha Gallego
- Laboratory of Experimental Research on Gynecology and Obstetrics, Gynecology, Obstetrics and Mastology Post Graduate Course, Botucatu Medical School, Univ Estadual Paulista_Unesp, Botucatu, São Paulo State, Brazil
| | - Yuri Karen Sinzato
- Laboratory of Experimental Research on Gynecology and Obstetrics, Gynecology, Obstetrics and Mastology Post Graduate Course, Botucatu Medical School, Univ Estadual Paulista_Unesp, Botucatu, São Paulo State, Brazil
| | - Carolina Abreu Miranda
- Laboratory of Experimental Research on Gynecology and Obstetrics, Gynecology, Obstetrics and Mastology Post Graduate Course, Botucatu Medical School, Univ Estadual Paulista_Unesp, Botucatu, São Paulo State, Brazil
| | - Isabela Lovizutto Iessi
- Laboratory of Experimental Research on Gynecology and Obstetrics, Gynecology, Obstetrics and Mastology Post Graduate Course, Botucatu Medical School, Univ Estadual Paulista_Unesp, Botucatu, São Paulo State, Brazil
| | - Bruna Dallaqua
- DeVry Ruy Barbosa School (DeVry Brazil Group), Salvador, Bahia State, Brazil
| | - Gustavo Tadeu Volpato
- Laboratory of System Physiology and Reproductive Toxicology, Institute of Biological and Health Sciences, Federal University of Mato Grosso (UFMT), Barra do Garças, Mato Grosso State, Brazil
| | - Wellerson Rodrigo Scarano
- Department of Morphology, Botucatu Bioscience Institute, Univ Estadual Paulista_Unesp, Botucatu, São Paulo State, Brazil
| | | | - Débora Cristina Damasceno
- Laboratory of Experimental Research on Gynecology and Obstetrics, Gynecology, Obstetrics and Mastology Post Graduate Course, Botucatu Medical School, Univ Estadual Paulista_Unesp, Botucatu, São Paulo State, Brazil.
| |
Collapse
|
7
|
Suh KS, Choi EM, Jung WW, Kim YJ, Hong SM, Park SY, Rhee SY, Chon S. Deoxyactein protects pancreatic β-cells against methylglyoxal-induced oxidative cell damage by the upregulation of mitochondrial biogenesis. Int J Mol Med 2017. [PMID: 28627583 DOI: 10.3892/ijmm.2017.3018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Methylglyoxal (MG) is one of the major precursors of advanced glycation end products (AGEs), which are considered to be one of the causes of diabetes and its complications. The root and rhizomes of black cohosh (Cimicifuga racemosa) have long been used medicinally, and deoxyactein is one of its major constituents. In the present study, the protective effects of deoxyactein against MG-induced oxidative cell damage were investigated in insulin-producing pancreatic β-cells. We found that deoxyactein protected the pancreatic β-cells against MG-induced cell death. Pre-treatment with deoxyactein significantly reduced the levels of intracellular reactive oxygen species (ROS), interleukin-1β (IL-1β), cardiolipin peroxidation, and protein adduct accumulation induced by MG. Pre-treatment of the cells with deoxyactein restored glyoxalase I activity and insulin secretion which were reduced by MG, and increased the mRNA expression of insulin 2 (INS2) and pancreatic and duodenal homeobox protein-1 (PDX-1). It also increased the levels of endogenous antioxidant enzymes, including superoxide dismutase (SOD) and glutathione peroxidase (GPX). Furthermore, treatment with deoxyactein increased the levels of sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α). These findings indicate that deoxyactein may exert beneficial effects on pancreatic β-cells via the upregulation of mitochondrial biogenesis. Taken together, these results suggest that deoxyactein may be used for the prevention of pancreatic β-cell damage.
Collapse
Affiliation(s)
- Kwang Sik Suh
- Research Institute of Endocrinology, Kyung Hee University Hospital, Seoul 130-702, Republic of Korea
| | - Eun Mi Choi
- Department of Endocrinology and Metabolism, School of Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Woon-Won Jung
- Department of Biomedical Laboratory Science, College of Health Sciences, Cheongju University, Cheongju, Chungbuk 360-764, Republic of Korea
| | - Yu Jin Kim
- Department of Medicine, Graduate School, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Soo Min Hong
- Department of Medicine, Graduate School, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - So Yong Park
- Department of Medicine, Graduate School, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Sang Youl Rhee
- Department of Endocrinology and Metabolism, School of Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| | - Suk Chon
- Department of Endocrinology and Metabolism, School of Medicine, Kyung Hee University, Seoul 130-702, Republic of Korea
| |
Collapse
|
8
|
Shah P, Lueschen N, Ardestani A, Oberholzer J, Olerud J, Carlsson PO, Maedler K. Angiopoetin-2 Signals Do Not Mediate the Hypervascularization of Islets in Type 2 Diabetes. PLoS One 2016; 11:e0161834. [PMID: 27617438 PMCID: PMC5019443 DOI: 10.1371/journal.pone.0161834] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Accepted: 08/12/2016] [Indexed: 12/12/2022] Open
Abstract
AIMS Changes in the islet vasculature have been implicated in the regulation of β-cell survival and function during the progression to type 2 diabetes (T2D). Failure of the β-cell to compensate for the increased insulin demand in obesity eventually leads to diabetes; as a result of the complex interplay of genetic and environmental factors (e.g. ongoing inflammation within the islets) and impaired vascular function. The Angiopoietin/Tie (Ang/Tie) angiogenic system maintains vasculature and is closely related to organ inflammation and angiogenesis. In this study we aimed to identify whether the vessel area within the islets changes in diabetes and whether such changes would be triggered by the Tie-antagonist Ang-2. METHODS Immunohistochemical and qPCR analyses to follow islet vascularization and Ang/Tie levels were performed in human pancreatic autopsies and isolated human and mouse islets. The effect of Ang-2 was assessed in β-cell-specific Ang-2 overexpressing mice during high fat diet (HFD) feeding. RESULTS Islet vessel area was increased in autopsy pancreases from patients with T2D. The vessel markers Tie-1, Tie-2 and CD31 were upregulated in mouse islets upon HFD feeding from 8 to 24 weeks. Ang-2 was transiently upregulated in mouse islets at 8 weeks of HFD and under glucolipotoxic conditions (22.2 mM glucose/ 0.5 mM palmitate) in vitro in human and mouse islets, in contrast to its downregulation by cytokines (IL-1β, IFN-ɣ and TNF-α). Ang-1 on the other hand was oppositely regulated, with a significant loss under glucolipotoxic condition, a trend to reduce in islets from patients with T2D and an upregulation by cytokines. Modulation of such changes in Ang-2 by its overexpression or the inhibition of its receptor Tie-2 impaired β-cell function at basal conditions but protected islets from cytokine induced apoptosis. In vivo, β-cell-specific Ang-2 overexpression in mice induced hypervascularization under normal diet but contrastingly led to hypovascularized islets in response to HFD together with increased apoptosis and reduced β-cell mass. CONCLUSIONS Islet hypervascularization occurs in T2D. A balanced expression of the Ang1/Ang2 system is important for islet physiology. Ang-2 prevents β-cell mass and islet vascular adaptation in response to HFD feeding with no major influence on glucose homeostasis.
Collapse
Affiliation(s)
- Payal Shah
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany
| | - Navina Lueschen
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany
| | - Amin Ardestani
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany
| | - Jose Oberholzer
- Division of Transplantation, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Johan Olerud
- Department of Immunology, Genetics and pathology, Uppsala University, Uppsala, Sweden
| | - Per-Ola Carlsson
- Department of Medical cell biology and Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Kathrin Maedler
- Centre for Biomolecular Interactions, University of Bremen, Bremen, Germany,German Center for Diabetes Research (DZD) project partner, University of Bremen, Bremen, Germany,* E-mail:
| |
Collapse
|
9
|
Diabetes mellitus related bone metabolism and periodontal disease. Int J Oral Sci 2015; 7:63-72. [PMID: 25857702 PMCID: PMC4817554 DOI: 10.1038/ijos.2015.2] [Citation(s) in RCA: 149] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/24/2014] [Indexed: 02/06/2023] Open
Abstract
Diabetes mellitus and periodontal disease are chronic diseases affecting a large number of populations worldwide. Changed bone metabolism is one of the important long-term complications associated with diabetes mellitus. Alveolar bone loss is one of the main outcomes of periodontitis, and diabetes is among the primary risk factors for periodontal disease. In this review, we summarise the adverse effects of diabetes on the periodontium in periodontitis subjects, focusing on alveolar bone loss. Bone remodelling begins with osteoclasts resorbing bone, followed by new bone formation by osteoblasts in the resorption lacunae. Therefore, we discuss the potential mechanism of diabetes-enhanced bone loss in relation to osteoblasts and osteoclasts.
Collapse
|
10
|
Pondugala PK, Sasikala M, Guduru VR, Rebala P, Nageshwar Reddy D. Interferon-γ Decreases Nuclear Localization of Pdx-1 and Triggers β-Cell Dysfunction in Chronic Pancreatitis. J Interferon Cytokine Res 2015; 35:523-9. [PMID: 25839229 DOI: 10.1089/jir.2014.0082] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Interferon-gamma (IFN-γ) is shown to play a major role in β-cell dysfunction in chronic pancreatitis (CP). However, the underlying mechanisms are to be elucidated. The present study was conducted to determine the role of IFN-γ subverting insulin gene expression in CP. Pancreatic tissues from control (n=15) and CP patients (n=30) were analyzed for nuclear localization of pancreatic and duodenal homeobox transcription factor (Pdx-1) after ascertaining their diabetic status. By immunofluorescence and western blot analysis, the influence of IFN-γ, anti-inflammatory cytokine (interleukin-10), and anti-IFN-γ agent epigallocatechin-3-gallate (EGCG) on nuclear localization of Pdx-1was examined in the islets isolated from resected normal pancreatic tissue. Nuclear localization of Pdx-1 was 20.25±2.19 in the islets of diabetic CP patients and 31.44±2.09 in nondiabetic CP patients as compared with controls (60.45±5.11) and the corresponding distribution of Pdx-1 protein in the nuclear compartment was also decreased. Exposure of normal islets to IFN-γ revealed decreased nuclear localization of Pdx-1. Pretreatment with polyphenolic compound EGCG restored the nuclear localization of Pdx-1. These results suggest that IFN-γ induced β-cell dysfunction is mediated through decreased nuclear localization of Pdx-1.
Collapse
Affiliation(s)
| | - M Sasikala
- 1 Asian Healthcare Foundation , Somajiguda, Hyderabad, India
| | - Venkat Rao Guduru
- 2 Asian Institute of Gastroenterology , Somajiguda, Hyderabad, India
| | - Pradeep Rebala
- 2 Asian Institute of Gastroenterology , Somajiguda, Hyderabad, India
| | - D Nageshwar Reddy
- 2 Asian Institute of Gastroenterology , Somajiguda, Hyderabad, India
| |
Collapse
|
11
|
Westwell-Roper CY, Chehroudi CA, Denroche HC, Courtade JA, Ehses JA, Verchere CB. IL-1 mediates amyloid-associated islet dysfunction and inflammation in human islet amyloid polypeptide transgenic mice. Diabetologia 2015; 58:575-85. [PMID: 25491100 DOI: 10.1007/s00125-014-3447-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 10/21/2014] [Indexed: 12/29/2022]
Abstract
AIMS/HYPOTHESIS Aggregation of islet amyloid polypeptide (IAPP) to form amyloid contributes to beta cell dysfunction in type 2 diabetes. Human but not non-amyloidogenic rodent IAPP induces islet macrophage proIL-1β synthesis. We evaluated the effect of IL-1 receptor antagonist (IL-1Ra) on islet inflammation and dysfunction in a mouse model of type 2 diabetes with amyloid formation. METHODS Lean and obese male mice (A/a or A(vy)/A at the agouti locus, respectively) with or without beta cell human IAPP expression (hIAPP(Tg/0)) were treated with PBS or IL-1Ra (50 mg kg(-1) day(-1)) from 16 weeks of age. Intraperitoneal glucose and insulin tolerance tests were performed after 8 weeks. Pancreases were harvested for histology and gene expression analysis. RESULTS Aggregation of human IAPP was associated with marked upregulation of proinflammatory gene expression in islets of obese hIAPP(Tg/0) mice, together with amyloid deposition and fasting hyperglycaemia. IL-1Ra improved glucose tolerance and reduced plasma proinsulin:insulin in both lean and obese hIAPP(Tg/0) mice with no effect on insulin sensitivity. The severity and prevalence of islet amyloid was reduced by IL-1Ra in lean hIAPP (Tg/0) mice, suggesting a feed-forward mechanism by which islet inflammation promotes islet amyloid at the early stages of disease. IL-1Ra limited Il1a, Il1b, Tnf and Ccl2 expression in islets from obese hIAPP(Tg/0) mice, suggesting an altered islet inflammatory milieu. CONCLUSIONS/INTERPRETATION These data provide the first in vivo evidence—using a transgenic mouse model with amyloid deposits resembling those found in human islets—that IAPP-induced beta cell dysfunction in type 2 diabetes may be mediated by IL-1. Anti-IL-1 therapies may limit islet inflammation and dysfunction associated with amyloid formation.
Collapse
Affiliation(s)
- Clara Y Westwell-Roper
- Department of Pathology & Laboratory Medicine, Child & Family Research Institute, University of British Columbia, Vancouver, BC, Canada
| | | | | | | | | | | |
Collapse
|
12
|
Johnson JS, Kono T, Tong X, Yamamoto WR, Zarain-Herzberg A, Merrins MJ, Satin LS, Gilon P, Evans-Molina C. Pancreatic and duodenal homeobox protein 1 (Pdx-1) maintains endoplasmic reticulum calcium levels through transcriptional regulation of sarco-endoplasmic reticulum calcium ATPase 2b (SERCA2b) in the islet β cell. J Biol Chem 2014; 289:32798-810. [PMID: 25271154 DOI: 10.1074/jbc.m114.575191] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Although the pancreatic duodenal homeobox 1 (Pdx-1) transcription factor is known to play an indispensable role in β cell development and secretory function, recent data also implicate Pdx-1 in the maintenance of endoplasmic reticulum (ER) health. The sarco-endoplasmic reticulum Ca(2+) ATPase 2b (SERCA2b) pump maintains a steep Ca(2+) gradient between the cytosol and ER lumen. In models of diabetes, our data demonstrated loss of β cell Pdx-1 that occurs in parallel with altered SERCA2b expression, whereas in silico analysis of the SERCA2b promoter revealed multiple putative Pdx-1 binding sites. We hypothesized that Pdx-1 loss under inflammatory and diabetic conditions leads to decreased SERCA2b levels and activity with concomitant alterations in ER health. To test this, siRNA-mediated knockdown of Pdx-1 was performed in INS-1 cells. The results revealed reduced SERCA2b expression and decreased ER Ca(2+), which was measured using fluorescence lifetime imaging microscopy. Cotransfection of human Pdx-1 with a reporter fused to the human SERCA2 promoter increased luciferase activity 3- to 4-fold relative to an empty vector control, and direct binding of Pdx-1 to the proximal SERCA2 promoter was confirmed by chromatin immunoprecipitation. To determine whether restoration of SERCA2b could rescue ER stress induced by Pdx-1 loss, Pdx1(+/-) mice were fed a high-fat diet. Isolated islets demonstrated an increased spliced-to-total Xbp1 ratio, whereas SERCA2b overexpression reduced the Xbp1 ratio to that of wild-type controls. Together, these results identify SERCA2b as a novel transcriptional target of Pdx-1 and define a role for altered ER Ca(2+) regulation in Pdx-1-deficient states.
Collapse
Affiliation(s)
| | | | - Xin Tong
- Cellular and Integrative Physiology and
| | | | - Angel Zarain-Herzberg
- the Departamento de Bioquimica, Facultad de Medicina, National Autonomous University of México, México City, 04510 México
| | - Matthew J Merrins
- the Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, and Department of Biomolecular Chemistry, University of Wisconsin Madison School of Medicine and Public Health, Madison, Wisconsin 53705
| | - Leslie S Satin
- the Department of Pharmacology and Brehm Center for Diabetes Research, University of Michigan Medical School, Ann Arbor, Michigan 48105
| | - Patrick Gilon
- the Pôle d'Endocrinologie, Diabète et Nutrition, Institut de Recherche Expérimentale et Clinique, Université Catholique de Louvain, Brussels, 1348 Belgium, and
| | - Carmella Evans-Molina
- From the Departments of Biochemistry and Molecular Biology, Medicine, and Cellular and Integrative Physiology and the Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana 46202, the Roudebush Veterans Affairs Medical Center, Indianapolis, Indiana 46202
| |
Collapse
|
13
|
Zhang Y, Ren C, Lu G, Mu Z, Cui W, Gao H, Wang Y. Anti-diabetic effect of mulberry leaf polysaccharide by inhibiting pancreatic islet cell apoptosis and ameliorating insulin secretory capacity in diabetic rats. Int Immunopharmacol 2014; 22:248-57. [DOI: 10.1016/j.intimp.2014.06.039] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 06/27/2014] [Accepted: 06/27/2014] [Indexed: 01/09/2023]
|
14
|
Anakinra treatment in patients with gout and type 2 diabetes. Clin Rheumatol 2014; 34:981-4. [PMID: 24733251 DOI: 10.1007/s10067-014-2601-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 03/20/2014] [Accepted: 03/29/2014] [Indexed: 01/01/2023]
Abstract
We report three Caucasian patients affected by gout and type 2 diabetes, who were treated with the recombinant nonglycosylated human interleukin-1 receptor antagonist anakinra (100 mg/day subcutaneously) after an unsatisfactory or incomplete response to urate-lowering therapy, colchicine, nonsteroidal anti-inflammatory drugs, and prednisone. The remarkable clinical improvement in joint symptoms within 24 h and in glycemic control during a 6-month period gives anakinra a potential therapeutic role in the management of gout and type 2 diabetes. When anakinra was discontinued, a gout attack occurred within 3-25 days in all three patients. The contribution of anakinra in the treatment of such syndromes is encouraging, but requires further studies to establish its long-term efficacy.
Collapse
|
15
|
Ardestani A, Paroni F, Azizi Z, Kaur S, Khobragade V, Yuan T, Frogne T, Tao W, Oberholzer J, Pattou F, Conte JK, Maedler K. MST1 is a key regulator of beta cell apoptosis and dysfunction in diabetes. Nat Med 2014; 20:385-397. [PMID: 24633305 PMCID: PMC3981675 DOI: 10.1038/nm.3482] [Citation(s) in RCA: 163] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 01/21/2014] [Indexed: 12/31/2022]
Abstract
Apoptotic cell death is a hallmark of the loss of insulin producing beta-cells in all forms of diabetes mellitus. Current treatment fails to halt the decline in functional beta-cell mass. Strategies to prevent beta-cell apoptosis and dysfunction are urgently needed. Here, we identified Mammalian Sterile 20-like kinase 1 (MST1) as a critical regulator of apoptotic beta-cell death and function. MST1 was strongly activated in beta-cells under diabetogenic conditions and correlated with beta-cell apoptosis. MST1 specifically induced the mitochondrial-dependent pathway of apoptosis in beta-cells through up-regulation of the BH3-only protein Bim. MST1 directly phosphorylated PDX1 at Thr11, resulting in its ubiquitination, degradation and impaired insulin secretion. Mst1 deficiency completely restored normoglycemia, beta-cell function and survival in vitro and in vivo. We show MST1 as novel pro-apoptotic kinase and key mediator of apoptotic signaling and beta-cell dysfunction, which may serve as target for the development of novel therapies for diabetes.
Collapse
Affiliation(s)
- Amin Ardestani
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| | - Federico Paroni
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| | - Zahra Azizi
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| | - Supreet Kaur
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| | | | - Ting Yuan
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| | - Thomas Frogne
- Department of Beta-cell Regeneration, Hagedorn Research Institute, Gentofte, Denmark
| | - Wufan Tao
- Institute of Developmental Biology and Molecular Medicine, Fudan University, Shanghai, China
| | - Jose Oberholzer
- Division of Transplantation, University of Illinois at Chicago, IL, USA
| | - Francois Pattou
- Thérapie Cellulaire du Diabète, INSERM /Université de Lille Nord de France, France
| | - Julie Kerr Conte
- Thérapie Cellulaire du Diabète, INSERM /Université de Lille Nord de France, France
| | - Kathrin Maedler
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| |
Collapse
|
16
|
Semache M, Ghislain J, Zarrouki B, Tremblay C, Poitout V. Pancreatic and duodenal homeobox-1 nuclear localization is regulated by glucose in dispersed rat islets but not in insulin-secreting cell lines. Islets 2014; 6:e982376. [PMID: 25437380 PMCID: PMC4588559 DOI: 10.4161/19382014.2014.982376] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The transcription factor Pancreatic and Duodenal Homeobox-1 (PDX-1) plays a major role in the development and function of pancreatic β-cells and its mutation results in diabetes. In adult β-cells, glucose stimulates transcription of the insulin gene in part by regulating PDX-1 expression, stability and activity. Glucose is also thought to modulate PDX-1 nuclear translocation but in vitro studies examining nucleo-cytoplasmic shuttling of endogenous or ectopically expressed PDX-1 in insulin-secreting cell lines have led to conflicting results. Here we show that endogenous PDX-1 undergoes translocation from the cytoplasm to the nucleus in response to glucose in dispersed rat islets but not in insulin-secreting MIN6, HIT-T15, or INS832/13 cells. Interestingly, however, we found that a PDX-1-GFP fusion protein can shuttle from the cytoplasm to the nucleus in response to glucose stimulation in HIT-T15 cells. Our results suggest that the regulation of endogenous PDX-1 sub-cellular localization by glucose is observed in primary islets and that care should be taken when interpreting data from insulin-secreting cell lines.
Collapse
Key Words
- ANOVA, analysis of variance
- BSA, bovine serum albumin
- DAPI, 4′, 6-diamidino-2-phenylindole
- DMEM, dulbecco's modified eagle medium
- EDTA, ethylenediaminetetraacetic acid
- GFP, green fluorescent protein
- HDAC, histone deacetylase
- HIT-T15
- INS832/13
- KRBH, krebs ringer bicarbonate hepes
- MIN6
- MODY, maturity-onset diabetes of the young
- PDX-1
- PDX-1, pancreatic and duodenal homeobox-1
- SEM, standard error of the mean
- SUMO, small ubiquitin-like modifier
- T2D, type 2 diabetes
- ZDF, zucker diabetic fatty
- glucose
- glucose-stimulated insulin secretion
- nucleo-cytoplasmic shuttling
- pancreatic β cells
Collapse
Affiliation(s)
- Meriem Semache
- Montreal Diabetes Research Center; CRCHUM; Montreal, QC, Canada
- Department of Biochemistry; University of Montreal; QC, Canada
| | - Julien Ghislain
- Montreal Diabetes Research Center; CRCHUM; Montreal, QC, Canada
| | - Bader Zarrouki
- Montreal Diabetes Research Center; CRCHUM; Montreal, QC, Canada
- Department of Medicine; University of Montreal; QC, Canada
| | | | - Vincent Poitout
- Montreal Diabetes Research Center; CRCHUM; Montreal, QC, Canada
- Department of Biochemistry; University of Montreal; QC, Canada
- Department of Medicine; University of Montreal; QC, Canada
- Correspondence to: Vincent Poitout;
| |
Collapse
|
17
|
Mahadevan J, Parazzoli S, Oseid E, Hertzel AV, Bernlohr DA, Vallerie SN, Liu CQ, Lopez M, Harmon JS, Robertson RP. Ebselen treatment prevents islet apoptosis, maintains intranuclear Pdx-1 and MafA levels, and preserves β-cell mass and function in ZDF rats. Diabetes 2013; 62:3582-8. [PMID: 23801580 PMCID: PMC3781455 DOI: 10.2337/db13-0357] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We reported earlier that β-cell-specific overexpression of glutathione peroxidase (GPx)-1 significantly ameliorated hyperglycemia in diabetic db/db mice and prevented glucotoxicity-induced deterioration of β-cell mass and function. We have now ascertained whether early treatment of Zucker diabetic fatty (ZDF) rats with ebselen, an oral GPx mimetic, will prevent β-cell deterioration. No other antihyperglycemic treatment was given. Ebselen ameliorated fasting hyperglycemia, sustained nonfasting insulin levels, lowered nonfasting glucose levels, and lowered HbA1c levels with no effects on body weight. Ebselen doubled β-cell mass, prevented apoptosis, prevented expression of oxidative stress markers, and enhanced intranuclear localization of pancreatic and duodenal homeobox (Pdx)-1 and v-maf musculoaponeurotic fibrosarcoma oncogene family, protein A (MafA), two critical insulin transcription factors. Minimal β-cell replication was observed in both groups. These findings indicate that prevention of oxidative stress is the mechanism whereby ebselen prevents apoptosis and preserves intranuclear Pdx-1 and MafA, which, in turn, is a likely explanation for the beneficial effects of ebselen on β-cell mass and function. Since ebselen is an oral antioxidant currently used in clinical trials, it is a novel therapeutic candidate to ameliorate fasting hyperglycemia and further deterioration of β-cell mass and function in humans undergoing the onset of type 2 diabetes.
Collapse
Affiliation(s)
- Jana Mahadevan
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - Susan Parazzoli
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - Elizabeth Oseid
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - Ann V. Hertzel
- Department of Biochemistry and Molecular Biology, University of Minnesota, Minneapolis, Minnesota
| | - David A. Bernlohr
- Department of Biochemistry and Molecular Biology, University of Minnesota, Minneapolis, Minnesota
| | - Sara N. Vallerie
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - Chang-qin Liu
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - Melissa Lopez
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - Jamie S. Harmon
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
| | - R. Paul Robertson
- Pacific Northwest Diabetes Research Institute and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, Washington
- Department of Biochemistry and Molecular Biology, University of Minnesota, Minneapolis, Minnesota
- Corresponding author: R. Paul Robertson,
| |
Collapse
|
18
|
Carnevale G, Riccio M, Pisciotta A, Beretti F, Maraldi T, Zavatti M, Cavallini GM, La Sala GB, Ferrari A, De Pol A. In vitro differentiation into insulin-producing β-cells of stem cells isolated from human amniotic fluid and dental pulp. Dig Liver Dis 2013; 45:669-76. [PMID: 23643565 DOI: 10.1016/j.dld.2013.02.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 01/21/2013] [Accepted: 02/06/2013] [Indexed: 12/11/2022]
Abstract
AIM To investigate the ability of human amniotic fluid stem cells and human dental pulp stem cells to differentiate into insulin-producing cells. METHODS Human amniotic fluid stem cells and human dental pulp stem cells were induced to differentiate into pancreatic β-cells by a multistep protocol. Islet-like structures were assessed in differentiated human amniotic fluid stem cells and human dental pulp stem cells after 21 days of culture by dithizone staining. Pancreatic and duodenal homebox-1, insulin and Glut-2 expression were detected by immunofluorescence and confocal microscopy. Insulin secreted from differentiated cells was tested with SELDI-TOF MS and by enzyme-linked immunosorbent assay. RESULTS Human amniotic fluid stem cells and human dental pulp stem cells, after 7 days of differentiation started to form islet-like structures that became evident after 14 days of induction. SELDI-TOF MS analysis, revealed the presence of insulin in the media of differentiated cells at day 14, further confirmed by enzyme-linked immunosorbent assay after 7, 14 and 21 days. Both stem cell types expressed, after differentiation, pancreatic and duodenal homebox-1, insulin and Glut-2 and were positively stained by dithizone. Either the cytosol to nucleus translocation of pancreatic and duodenal homebox-1, either the expression of insulin, are regulated by glucose concentration changes. Day 21 islet-like structures derived from both human amniotic fluid stem cells and human dental pulp stem cell release insulin in a glucose-dependent manner. CONCLUSION The present study demonstrates the ability of human amniotic fluid stem cells and human dental pulp stem cell to differentiate into insulin-producing cells, offering a non-pancreatic, low-invasive source of cells for islet regeneration.
Collapse
Affiliation(s)
- Gianluca Carnevale
- Department of Surgery, Medicine, Dentistry and Morphological Sciences with Interest in Transplant, Oncology and Regenerative Medicine, University of Modena and Reggio Emilia, Modena, Italy.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
The NLRP3 Inflammasome as a novel player of the intercellular crosstalk in metabolic disorders. Mediators Inflamm 2013; 2013:678627. [PMID: 23843683 PMCID: PMC3697790 DOI: 10.1155/2013/678627] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 05/13/2013] [Accepted: 05/22/2013] [Indexed: 01/13/2023] Open
Abstract
The combination of obesity and type 2 diabetes is a serious health problem, which is projected to afflict 300 million people worldwide by 2020. Both clinical and translational laboratory studies have demonstrated that chronic inflammation is associated with obesity and obesity-related conditions such as insulin resistance. However, the precise etiopathogenetic mechanisms linking obesity to diabetes remain to be elucidated, and the pathways that mediate this phenomenon are not fully characterized. One of the most recently identified signaling pathways, whose activation seems to affect many metabolic disorders, is the “inflammasome,” a multiprotein complex composed of NLRP3 (nucleotide-binding domain and leucine-rich repeat protein 3), ASC (apoptosis-associated speck-like protein containing a CARD), and procaspase-1. NLRP3 inflammasome activation leads to the processing and secretion of the proinflammatory cytokines interleukin- (IL-) 1β and IL-18. The goal of this paper is to review new insights on the effects of the NLRP3 inflammasome activation in the complex mechanisms of crosstalk between different organs, for a better understanding of the role of chronic inflammation in metabolic disease pathogenesis. We will provide here a perspective on the current research on NLRP3 inflammasome, which may represent an innovative therapeutic target to reverse the detrimental metabolic consequences of the metabolic inflammation.
Collapse
|
20
|
Pham MN, Kolb H, Battelino T, Ludvigsson J, Pozzilli P, Zivehe F, Roden M, Mandrup-Poulsen T, Schloot NC. Fasting and meal-stimulated residual beta cell function is positively associated with serum concentrations of proinflammatory cytokines and negatively associated with anti-inflammatory and regulatory cytokines in patients with longer term type 1 diabetes. Diabetologia 2013; 56:1356-63. [PMID: 23494449 DOI: 10.1007/s00125-013-2883-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 02/14/2013] [Indexed: 01/01/2023]
Abstract
AIMS/HYPOTHESIS Cytokines may promote or inhibit disease progression in type 1 diabetes. We investigated whether systemic proinflammatory, anti-inflammatory and regulatory cytokines associated differently with fasting and meal-stimulated beta cell function in patients with longer term type 1 diabetes. METHODS The beta cell function of 118 patients with type 1 diabetes of duration of 0.75-4.97 years was tested using a standardised liquid mixed meal test (MMT). Serum samples obtained at -5 to 120 min were analysed by multiplex bead-based technology for proinflammatory (IL-6, TNF-α), anti-inflammatory (IL-1 receptor antagonist [IL-1RA]) and regulatory (IL-10, TGF-β1-3) cytokines, and by standard procedures for C-peptide. Differences in beta cell function between patient groups were assessed using stepwise multiple regression analysis adjusting for sex, age, duration of diabetes, BMI, HbA1c and fasting blood glucose. RESULTS High fasting systemic concentrations of the proinflammatory cytokines IL-6 and TNF-α were associated with increased fasting and stimulated C-peptide concentrations even after adjustment for confounders (p < 0.03). Interestingly, increased concentrations of anti-inflammatory/regulatory IL-1RA, IL-10, TGF-β1 and TGF-β2 were associated with lower fasting and stimulated C-peptide levels (p < 0.04), losing significance on adjustment for anthropometric variables. During the MMT, circulating concentrations of IL-6 and TNF-α increased (p < 0.001) while those of IL-10 and TGF-β1 decreased (p < 0.02) and IL-1RA and TGF-β2 remained unchanged. CONCLUSIONS/INTERPRETATION The association between better preserved beta cell function in longer term type 1 diabetes and increased systemic proinflammatory cytokines and decreased anti-inflammatory and regulatory cytokines is suggestive of ongoing inflammatory disease activity that might be perpetuated by the remaining beta cells. These findings should be considered when designing immune intervention studies aimed at patients with longer term type 1 diabetes and residual beta cell function.
Collapse
Affiliation(s)
- M N Pham
- Institute for Clinical Diabetology at the German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich-Heine-University Düsseldorf, Auf'm Hennekamp 65, 40225 Düsseldorf, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Lee SC, Xu WX, Lin LY, Yang JJ, Liu CT. Chemical composition and hypoglycemic and pancreas-protective effect of leaf essential oil from indigenous cinnamon (Cinnamomum osmophloeum Kanehira). JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:4905-4913. [PMID: 23627599 DOI: 10.1021/jf401039z] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The antidiabetic effect of cinnamon has generated broad interest during the past decade. We investigated the hypoglycemic activity and pancreas-protective effect of leaf essential oil from indigenous cinnamon (CO) in diabetic rats induced with streptozotocin (STZ, iv, 65 mg/(kg bw)) and found linalool to be the major component representing 40.24% of the CO composition. In diabetics, all tested doses of CO significantly lowered fasting blood glucose and fructosamine and are concomitant with elevated plasma and pancreatic insulin levels under a fasting condition. However, during the oral glucose tolerance test (OGTT) period the effect of 25 and 50 mg/(kg bw) of CO was shown to be less effective than that of 12.5 mg/(kg bw) in ameliorating the accumulation of plasma insulin. In addition, at 12.5 mg/(kg bw), CO significantly ameliorated pancreatic values of thiobarbituric acid reactive substances and activities of superoxide dismutase and glutathione reductase in diabetics to an extent greater than that of higher CO doses. At doses 12.5 and 25 but not 50 mg/(kg bw), CO significantly ameliorated pancreatic levels of interleukin-1β and nitric oxide. In conclusion, appropriate doses of CO of the linalool chemotype exhibited therapeutic potential in glycemic control in diabetes that was at least partially resulted from improved insulin secretion. The ameliorated oxidative stress and proinflammatory environment in the pancreas by CO may provide a protective effect on pancreatic β cells and warrant further investigation.
Collapse
Affiliation(s)
- Shih-Chieh Lee
- Department of BioIndustry Technology, Da-Yeh University, Changhua 51591, Taiwan, Republic of China
| | | | | | | | | |
Collapse
|
22
|
Grant RW, Dixit VD. Mechanisms of disease: inflammasome activation and the development of type 2 diabetes. Front Immunol 2013; 4:50. [PMID: 23483669 PMCID: PMC3592198 DOI: 10.3389/fimmu.2013.00050] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 02/10/2013] [Indexed: 12/23/2022] Open
Abstract
Over the recent past, the importance of aberrant immune cell activation as one of the contributing mechanisms to the development of insulin-resistance and type 2 diabetes (T2D) has been recognized. Among the panoply of pro-inflammatory cytokines that are linked to chronic metabolic diseases, new data suggests that interleukin-1β (IL-1β) may play an important role in initiating and sustaining inflammation-induced organ dysfunction in T2D. Therefore, factors that control secretion of bioactive IL-1β have therapeutic implications. In this regard, the identification of multiprotein scaffolding complexes, "inflammasomes," has been a great advance in our understanding of this process. The secretion of bioactive IL-1β is predominantly controlled by activation of caspase-1 through assembly of a multiprotein scaffold, "inflammasome" that is composed of NLRP3 (nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3) ASC (apoptosis associated speck-like protein containing a CARD) and procaspase-1. The NLRP3 inflammasome appears to be an important sensor of metabolic dysregulation and controls obesity-associated insulin resistance and pancreatic beta cell dysfunction. Initial clinical "proof of concept" studies suggest that blocking IL-1β may favorably modulate factors related to development and treatment of T2D. However, this potential therapeutic approach remains to be fully substantiated through phase-II clinical studies. Here, we outline the new immunological mechanisms that link metabolic dysfunction to the emergence of chronic inflammation and discuss the opportunities and challenges of future therapeutic approaches to dampen NLRP3 inflammasome activation or IL-1β signaling for controlling type 2 diabetes.
Collapse
Affiliation(s)
- Ryan W Grant
- Immunobiology Laboratory, Pennington Biomedical Research Center, Louisiana State University System Baton Rouge, LA, USA
| | | |
Collapse
|
23
|
Shu L, Zien K, Gutjahr G, Oberholzer J, Pattou F, Kerr-Conte J, Maedler K. TCF7L2 promotes beta cell regeneration in human and mouse pancreas. Diabetologia 2012; 55:3296-307. [PMID: 22945304 DOI: 10.1007/s00125-012-2693-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 07/17/2012] [Indexed: 11/25/2022]
Abstract
AIMS/HYPOTHESIS Diabetes is characterised by loss and dysfunction of the beta cell. A major goal of diabetes therapy is to promote the formation of new beta cells. Polymorphisms of T cell factor 7-like 2 (TCF7L2) are associated with type 2 diabetes, negatively regulating beta cell survival and function. Here, we provide evidence for a role of TCF7L2 in beta cell proliferation and regeneration. METHODS Pancreatic sections from three mouse models (high-fat diet, exendin-4 and streptozotocin-treated mice) and from healthy individuals and patients with type 2 diabetes were used to investigate the association of beta cell regeneration and TCF7L2 levels. To analyse a direct effect of TCF7L2 on duct cell to beta cell conversion, TCF7L2 was overexpressed in isolated exocrine cells. RESULTS TCF7L2 levels correlated with beta cell compensation during high-fat diet feeding. TCF7L2 was increased together with pancreatic duct cell proliferation and differentiation. Small islet-like cell clusters (ICCs) that contained TCF7L2 originated in the vicinity of the ductal epithelium. In human isolated exocrine tissue, TCF7L2 overexpression induced proliferation of pancreatic duct cells and ICC formation next to duct cells, an effect dependent on the JAK2/STAT3 pathway. CONCLUSIONS/INTERPRETATION The present study demonstrates that TCF7L2 overexpression fosters beta cell regeneration. Our findings imply correlation of TCF7L2 levels and new beta cell formation.
Collapse
Affiliation(s)
- L Shu
- Centre for Biomolecular Interactions Bremen, University of Bremen, Leobener Strasse NW2, Bremen, Germany
| | | | | | | | | | | | | |
Collapse
|
24
|
Novotny GW, Lundh M, Backe MB, Christensen DP, Hansen JB, Dahllöf MS, Pallesen EMH, Mandrup-Poulsen T. Transcriptional and translational regulation of cytokine signaling in inflammatory β-cell dysfunction and apoptosis. Arch Biochem Biophys 2012; 528:171-84. [PMID: 23063755 DOI: 10.1016/j.abb.2012.09.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Revised: 09/20/2012] [Accepted: 09/22/2012] [Indexed: 12/19/2022]
Abstract
Disease is conventionally viewed as the chaotic inappropriate outcome of deranged tissue function resulting from aberrancies in cellular processes. Yet the patho-biology of cellular dysfunction and death encompasses a coordinated network no less sophisticated and regulated than maintenance of homeostatic balance. Cellular demise is far from passive subordination to stress but requires controlled coordination of energy-requiring activities including gene transcription and protein translation that determine the graded transition between defensive mechanisms, cell cycle regulation, dedifferentiation and ultimately to the activation of death programmes. In fact, most stressors stimulate both homeostasis and regeneration on one hand and impairment and destruction on the other, depending on the ambient circumstances. Here we illustrate this bimodal ambiguity in cell response by reviewing recent progress in our understanding of how the pancreatic β cell copes with inflammatory stress by changing gene transcription and protein translation by the differential and interconnected action of reactive oxygen and nitric oxide species, microRNAs and posttranslational protein modifications.
Collapse
Affiliation(s)
- Guy W Novotny
- Section of Endocrinological Research, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Dharmadhikari G, Mühle M, Schulthess FT, Laue S, Oberholzer J, Pattou F, Kerr-Conte J, Maedler K. TOSO promotes β-cell proliferation and protects from apoptosis. Mol Metab 2012; 1:70-8. [PMID: 24024120 DOI: 10.1016/j.molmet.2012.08.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 08/03/2012] [Accepted: 08/03/2012] [Indexed: 01/09/2023] Open
Abstract
Decreased β-cell mass reflects a shift from quiescence/proliferation into apoptosis, it plays a crucial role in the pathophysiology of diabetes. A major attempt to restore β-cell mass and normoglycemia is to improve β-cell survival. Here we show that switching off the Fas pathway using Fas apoptotic inhibitory protein (Faim/TOSO), which regulates apoptosis upstream of caspase 8, blocked β-cell apoptosis and increased proliferation in human islets. TOSO was clearly expressed in pancreatic β-cells and down-regulated in T2DM. TOSO expression correlated with β-cell turnover; at conditions of improved survival, TOSO was induced. In contrast, TOSO downregulation induced β-cell apoptosis. Although TOSO overexpression resulted in a 3-fold induction of proliferation, proliferating β-cells showed a very limited capacity to undergo multiple rounds of replication. Our data suggest that TOSO is an important regulator of β-cell turnover and switches β-cell apoptosis into proliferation.
Collapse
Affiliation(s)
- G Dharmadhikari
- Centre for Biomolecular Interactions Bremen, University of Bremen, Germany
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Goehring I, Sauter NS, Catchpole G, Assmann A, Shu L, Zien KS, Moehlig M, Pfeiffer AFH, Oberholzer J, Willmitzer L, Spranger J, Maedler K. Identification of an intracellular metabolic signature impairing beta cell function in the rat beta cell line INS-1E and human islets. Diabetologia 2011; 54:2584-94. [PMID: 21796486 DOI: 10.1007/s00125-011-2249-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 06/06/2011] [Indexed: 12/12/2022]
Abstract
AIMS/HYPOTHESIS Chronic hyperglycaemia promotes the progressive failure of pancreatic beta cells in patients with type 2 diabetes mellitus, a clinically highly relevant phenomenon known as glucotoxicity. The intracellular metabolic consequences of a chronically high availability of glucose in beta cells are, as yet, poorly understood in its full complexity. METHODS An unbiased metabolite profiling analysis (GC-time-of-flight-MS) was used to identify the time course of core metabolite patterns in rat beta cell line INS-1E during exposure to high glucose concentrations and its relation to insulin expression. RESULTS We report here that pentose phosphate pathway (PPP) metabolites accumulate remarkably during chronic but not acute glucose treatment, indicating altered processing of glucose through the pentose phosphate pathway. Subsequent functional studies in INS-1E cells and human islets revealed that a disturbance in this pathway contributes to decreases in insulin gene expression and a lack of glucose-stimulated insulin secretion. These effects were found to depend on the activation of extracellular-regulated-kinase (ERK1/2). Long-term inhibition of 6-phosphogluconic acid dehydrogenase resulted in accumulation of PPP metabolites, induced ERK1/2 activation independently of high glucose and impaired beta cell function. In turn, inhibition of ERK1/2 overstimulation during chronic glucose exposure partly inhibited metabolite accumulation and restored beta cell function. CONCLUSIONS/INTERPRETATION Based on unbiased metabolite analyses, the data presented here provide novel targets, namely the inhibition of PPP metabolite accumulation towards the therapeutic goal to preserve and potentially improve beta cell function in diabetes.
Collapse
Affiliation(s)
- I Goehring
- Department of Endocrinology, Diabetes and Nutrition, Charité-Universitaetsmedizin Berlin, Nuthetal, Germany
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|