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Dardano A, Daniele G, Lupi R, Napoli N, Campani D, Boggi U, Del Prato S, Miccoli R. Nesidioblastosis and Insulinoma: A Rare Coexistence and a Therapeutic Challenge. Front Endocrinol (Lausanne) 2020; 11:10. [PMID: 32047477 PMCID: PMC6996476 DOI: 10.3389/fendo.2020.00010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 01/07/2020] [Indexed: 01/04/2023] Open
Abstract
Background: Nesidioblastosis and insulinoma are disorders of the endocrine pancreas causing endogenous hyperinsulinemic hypoglycemia. Their coexistence is very unusual and treatment represents a still unresolved dilemma. Case Description: The patient was a 43-year-old Caucasian woman, with a 2-year history of repeated severe hypoglycemic events. The diagnostic work-up was strongly suggestive of insulinoma and the patient was submitted to surgical treatment carried out laparoscopically under robotic assistance. However, surgical exploration and intraoperative ultrasonography failed to detect a pancreatic tumor. Resection was therefore carried out based on the results of selective intra-arterial calcium stimulation test, following a step-up approach, eventually leading to a pancreatoduodenectomy at the splenic artery. The histopathology examination and the immunohistochemical staining were consistent with adult-onset nesidioblastosis. After surgery, the patient continued to experience hypoglycemia with futile response to medical treatments (octreotide, calcium antagonists, diazoxide, and prednisone). Following multidisciplinary evaluation and critical review of a repeat abdominal computed tomography scan, a small nodular lesion was identified in the tail of the pancreas. The nodule was enucleated laparoscopically and the pathological examination revealed an insulinoma. In spite of the insulinoma resection, glycemic values were only partially restored, with residual nocturnal hypoglycemia. Administration of uncooked cornstarch (1.25 g/kg body weight) at bedtime was associated with significant improvement of interstitial glucose levels (p < 0.0001) and reduction of nocturnal hypoglycemia episodes (p = 0.0002). Conclusions: This report describes a rare coexistence of adult-onset nesidioblastosis and insulinoma, suggesting the existence of a wide and continuous spectrum of proliferative β-cell changes. Moreover, we propose that uncooked cornstarch may offer an additional approach to alleviate the hypoglycemic episodes when surgery is impracticable/unaccepted.
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Affiliation(s)
- Angela Dardano
- Section of Diabetes and Metabolic Disease, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
- *Correspondence: Angela Dardano
| | - Giuseppe Daniele
- Section of Diabetes and Metabolic Disease, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Roberto Lupi
- Section of Diabetes and Metabolic Disease, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Niccolò Napoli
- Division of General and Transplant Surgery, University of Pisa, Pisa, Italy
| | | | - Ugo Boggi
- Division of General and Transplant Surgery, University of Pisa, Pisa, Italy
| | - Stefano Del Prato
- Section of Diabetes and Metabolic Disease, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Roberto Miccoli
- Section of Diabetes and Metabolic Disease, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
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Lupi R, Denery-Papini S, Claude M, Tranquet O, Drouet M, Masci S, Larré C. Thermal treatment reduces gliadin recognition by IgE, but a subsequent digestion and epithelial crossing permits recovery. Food Res Int 2018; 118:22-31. [PMID: 30898348 DOI: 10.1016/j.foodres.2018.02.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 01/19/2018] [Accepted: 02/02/2018] [Indexed: 01/01/2023]
Abstract
Wheat is one of the most important crops in the world in terms of human nutrition. With regards to health, some individuals exhibit wheat-related disorders such as food allergy to wheat (FAW). In this disorder, gluten is involved, particularly the gliadins which are among the main proteins responsible for FAW. Food processing, as well as digestibility and intestinal transport are key factors to consider since they may affect the allergenic potential of food allergens. Wheat is always consumed after heat processing and this step may impact epitope accessibility by inducing aggregation and may irreversibly destroy conformational epitopes. Our aim was to investigate the effects of heating and digestion on the structure of well-known allergens (total gliadins and α-gliadins) and their capacity to maintain their allergenic potential after crossing an intestinal barrier. The sizes of the processed (heated and heated/digested) proteins were characterized by laser light scattering and chromatographic reverse phase. The IgE-binding capacities of native and processed proteins were checked using a dot blot with sera from wheat allergenic patients. Furthermore, the abilities of these samples to cross the intestinal barrier and to induce mast cell degranulation were investigated by combining two in vitro cellular models, Caco-2 and RBL-SX38. The heat treatment of total gliadins and α-gliadins induced the production of large aggregates that were hardly recognized by IgE of patients in dot-blot. However, after limited pepsin hydrolysis, the epitopes were unmasked, and they were able to bind IgE again. Native proteins (gliadins and α-type) and processed forms were able to cross the Caco-2 cells in small amount. Permeability studies revealed the capacity of α-gliadins to increase paracellular permeability. In the RBL assay, the total native gliadins were able to trigger cell degranulation, but none of their processed forms. However after crossing the CaCo-2 monolayer, processed gliadins recovered their degranulation capacity to a certain extent. Total native gliadins remained the best allergenic form compared to α-type.
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Affiliation(s)
- R Lupi
- University of Tuscia, Department of Agricultural and Forestry Science, Via S. Camillo de Lellis s.n.c., 01100 Viterbo, Italy; INRA, UR 1268 Biopolymers Interactions Assemblies, 44316 Nantes, France.
| | - S Denery-Papini
- INRA, UR 1268 Biopolymers Interactions Assemblies, 44316 Nantes, France.
| | - M Claude
- INRA, UR 1268 Biopolymers Interactions Assemblies, 44316 Nantes, France
| | - O Tranquet
- INRA, UR 1268 Biopolymers Interactions Assemblies, 44316 Nantes, France.
| | - M Drouet
- CHU d'Angers, Unité Allergologie Générale, F-49000 Angers, France.
| | - S Masci
- University of Tuscia, Department of Agricultural and Forestry Science, Via S. Camillo de Lellis s.n.c., 01100 Viterbo, Italy.
| | - C Larré
- INRA, UR 1268 Biopolymers Interactions Assemblies, 44316 Nantes, France.
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Sancho V, Daniele G, Lucchesi D, Lupi R, Ciccarone A, Penno G, Bianchi C, Dardano A, Miccoli R, Del Prato S. Metabolic regulation of GLP-1 and PC1/3 in pancreatic α-cell line. PLoS One 2017; 12:e0187836. [PMID: 29121068 PMCID: PMC5679617 DOI: 10.1371/journal.pone.0187836] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 10/26/2017] [Indexed: 12/15/2022] Open
Abstract
Background and aims An intra-islet incretin system has been recently suggested to operate through modulation of the expression and activity of proconvertase 1/3 and 2 (PC1/3, PC2) in pancreatic alpha-cell accounting for local release of GLP-1. Little is known, whether this alpha-cell activity can be affected by the metabolic alterations occurring in type 2 diabetes, such as hyperglycemia, hyperlipidemia or hyperglucagonemia. Materials and methods AlphaTC1/6 cells from a mice pancreatic cell line were incubated in the presence of two glucose (G) concentration (5.5 and 16.7 mM) for 16 h with or without free fatty acid, IL6 or glucagon. GLP-1 secretion was measured by ELISA and expression of PC1/3 and PC2 by RT-PCR and western blot; cell viability was determined by MTT method, Reactive Oxygen Species generation (ROS) by H2DCFDA fluorescence and apoptosis by Annexin staining and Propidium Iodine (PI) fluorescence. Results Upon 16.7G incubation, GLP-1 secretion (total and active) was significantly increased in parallel with a significant increment in PC1/3 expression, a slight increase in cell viability and ROS generation and by a decrement in PC2 expression with no change in cell apoptosis. When cells were incubated at 5.5mM glucose with FFA, also an increment in GLP-1 secretion and PC1/3 expression was observed together an increment in ROS generation, a decrement in cell viability, and a modest increment in apoptosis. When incubated with 16.7mM glucose with FFA, the increment in GLP-1 secretion was reduced to basal, accompanied by an increment in apoptosis and ROS generation. This was also observed with IL-6, but in this case, no modification in ROS generation or apoptosis was observed when compared to 16.7mM glucose. The presence of glucagon did not modify any of the parameters studied. Conclusion These data suggest that under hyperglycemic, hyperlipidemia or inflammatory conditions, alpha cells can increase expression PC1/3 and activate GLP-1 secretion, which may contribute protecting both alpha and beta-cells from glucose and lipotoxicity, while this effect seems to be lost in the presence of both pathophysiological conditions.
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Affiliation(s)
- Veronica Sancho
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
| | - Giuseppe Daniele
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
| | - Daniela Lucchesi
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
| | - Roberto Lupi
- Section of Diabetes and Metabolic Diseases, Azienda Ospedaliero–Universitaria Pisana, Cisanello Hospital, Pisa, Italy
| | - Annamaria Ciccarone
- Section of Diabetes and Metabolic Diseases, Azienda Ospedaliero–Universitaria Pisana, Cisanello Hospital, Pisa, Italy
| | - Giuseppe Penno
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
| | - Cristina Bianchi
- Section of Diabetes and Metabolic Diseases, Azienda Ospedaliero–Universitaria Pisana, Cisanello Hospital, Pisa, Italy
| | - Angela Dardano
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
| | - Roberto Miccoli
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
| | - Stefano Del Prato
- Department of Clinical and Experimental Medicine, Section of Diabetes and Metabolic Diseases, University of Pisa – Cisanello Hospital, Pisa, Italy
- * E-mail:
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Ardestani A, Sauter NS, Paroni F, Dharmadhikari G, Cho JH, Lupi R, Marchetti P, Oberholzer J, Kerr Conte J, Maedler K. Neutralizing interleukin 1β (IL-1β) induces β-cell survival by maintaining PDX1 protein nuclear localization. J Biol Chem 2016; 290:27532. [PMID: 26567296 DOI: 10.1074/jbc.a110.210526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Claude M, Lupi R, Bouchaud G, Bodinier M, Brossard C, Denery-Papini S. The thermal aggregation of ovalbumin as large particles decreases its allergenicity for egg allergic patients and in a murine model. Food Chem 2016; 203:136-144. [PMID: 26948598 DOI: 10.1016/j.foodchem.2016.02.054] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 01/14/2016] [Accepted: 02/09/2016] [Indexed: 01/05/2023]
Abstract
Most egg-allergic children can tolerate extensively cooked eggs. Ovalbumin, a major allergen in egg whites, is prone to aggregate upon heating. This study compares ovalbumin's allergenicity when it is aggregated as large particles to ovalbumin in its native form. Immunoglobulins (Ig)-binding and the degranulation capacities of native and aggregated ovalbumin were measured with sera from egg-allergic children and from mice sensitized to native or aggregated ovalbumin. The influence of ovalbumin structure on Ig production upon sensitization and elicitation potency by challenge was also studied. We showed that heat aggregation of ovalbumin as large particles enhances IgG production and promotes IgG2a production (a shift toward the T helper 1 profile). Aggregated ovalbumin displayed lower Ig-binding and basophil-activation capacities for sera from both allergic patients and mice. This work illustrates the links between ovalbumin structure after heating and allergenicity potential using parameters from both the sensitization and elicitation phases of the allergic reaction.
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Affiliation(s)
- M Claude
- INRA, UR 1268 BIA (Biopolymers, Interactions, Assemblies), F-44316, rue de la Géraudière, 44316 Nantes, France
| | - R Lupi
- INRA, UR 1268 BIA (Biopolymers, Interactions, Assemblies), F-44316, rue de la Géraudière, 44316 Nantes, France
| | - G Bouchaud
- INRA, UR 1268 BIA (Biopolymers, Interactions, Assemblies), F-44316, rue de la Géraudière, 44316 Nantes, France
| | - M Bodinier
- INRA, UR 1268 BIA (Biopolymers, Interactions, Assemblies), F-44316, rue de la Géraudière, 44316 Nantes, France
| | - C Brossard
- INRA, UR 1268 BIA (Biopolymers, Interactions, Assemblies), F-44316, rue de la Géraudière, 44316 Nantes, France.
| | - S Denery-Papini
- INRA, UR 1268 BIA (Biopolymers, Interactions, Assemblies), F-44316, rue de la Géraudière, 44316 Nantes, France
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Lupi R, Masci S, Rogniaux H, Tranquet O, Brossard C, Lafiandra D, Moneret-Vautrin D, Denery-Papini S, Larré C. Assessment of the allergenicity of soluble fractions from GM and commercial genotypes of wheats. J Cereal Sci 2014. [DOI: 10.1016/j.jcs.2014.02.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Lupi R, Masci S, Pineau F, Denery-Papini S, Larré C. Variability of allergenicity within 29 genotypes including some genetically modified genotypes. Clin Transl Allergy 2013. [PMCID: PMC3723677 DOI: 10.1186/2045-7022-3-s3-p91] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Marchetti P, Lupi R, Bugliani M, Kirkpatrick CL, Sebastiani G, Grieco FA, Del Guerra S, D'Aleo V, Piro S, Marselli L, Boggi U, Filipponi F, Tinti L, Salvini L, Wollheim CB, Purrello F, Dotta F. A local glucagon-like peptide 1 (GLP-1) system in human pancreatic islets. Diabetologia 2012; 55:3262-72. [PMID: 22965295 DOI: 10.1007/s00125-012-2716-9] [Citation(s) in RCA: 180] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 08/08/2012] [Indexed: 12/25/2022]
Abstract
AIMS/HYPOTHESIS Glucagon-like peptide 1 (GLP-1) is a major incretin, mainly produced by the intestinal L cells, with beneficial actions on pancreatic beta cells. However, while in vivo only very small amounts of GLP-1 reach the pancreas in bioactive form, some observations indicate that GLP-1 may also be produced in the islets. We performed comprehensive morphological, functional and molecular studies to evaluate the presence and various features of a local GLP-1 system in human pancreatic islet cells, including those from type 2 diabetic patients. METHODS The presence of insulin, glucagon, GLP-1, proconvertase (PC) 1/3 and PC2 was determined in human pancreas by immunohistochemistry with confocal microscopy. Islets were isolated from non-diabetic and type 2 diabetic donors. GLP-1 protein abundance was evaluated by immunoblotting and matrix-assisted laser desorption-ionisation-time of flight (MALDI-TOF) mass spectrometry. Single alpha and beta cell suspensions were obtained by enzymatic dissociation and FACS sorting. Glucagon and GLP-1 release were measured in response to nutrients. RESULTS Confocal microscopy showed the presence of GLP-1-like and PC1/3 immunoreactivity in subsets of alpha cells, whereas GLP-1 was not observed in beta cells. The presence of GLP-1 in isolated islets was confirmed by immunoblotting, followed by mass spectrometry. Isolated islets and alpha (but not beta) cell fractions released GLP-1, which was regulated by glucose and arginine. PC1/3 (also known as PCSK1) gene expression was shown in alpha cells. GLP-1 release was significantly higher from type 2 diabetic than from non-diabetic isolated islets. CONCLUSIONS/INTERPRETATION We have shown the presence of a functionally competent GLP-1 system in human pancreatic islets, which resides in alpha cells and might be modulated by type 2 diabetes.
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Affiliation(s)
- P Marchetti
- Department of Endocrinology and Metabolism, University of Pisa, Via Paradisa 2, Pisa, Italy.
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Gasparri F, Carugo A, Galvani A, Gianellini L, Giorgini M, Isacchi A, Lupi R, Perrera C, Raddrizzani L, Colombo R. 231 A Novel siRNA Screening Approach for Target Identification in Oncology: Focus On Purinome Enzymes. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)72029-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Del Guerra S, D'Aleo V, Gualtierotti G, Pandolfi R, Boggi U, Vistoli F, Barnini S, Filipponi F, Del Prato S, Lupi R. Evidence for a role of frataxin in pancreatic islets isolated from multi-organ donors with and without type 2 diabetes mellitus. Horm Metab Res 2012; 44:471-5. [PMID: 22399236 DOI: 10.1055/s-0032-1301920] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Frataxin (FXN) is a mitochondrial protein involved in iron metabolism and in the modulation of reactive oxygen and/or nitrogen species production. No information is currently available as for the role of frataxin in isolated human pancreatic islets. We studied islets from pancreases of multi-organ donors with (T2DM) and without (Ctrl) Type 2 diabetes mellitus. In these islets, we determined FXN gene and protein expression by qualitative and quantitative Real-Time RT-PCR, nitrotyrosine concentration, and insulin release in response to glucose stimulation (SI). FXN gene and protein were expressed in human islets, though the level of expression was much lower in T2DM islets. The latter also had lower insulin release and higher concentration of nitrotyrosine. A positive correlation was apparent between SI and FXN gene expression, while a negative correlation was found between nitrotyrosine islet concentration and FXN expression. Transfection of Ctrl islets with siRNA FXN caused reduction of FXN expression, increase of nitrotyrosine concentration, and reduction of insulin release. In conclusion, in human pancreatic islets FXN contributes to regulation of oxidative stress and insulin release in response to glucose. In islets from T2DM patients FXN expression is reduced while oxidative stress is increased and insulin release in response to glucose impaired.
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Affiliation(s)
- S Del Guerra
- Department of Endocrinology and Metabolism, Section of Metabolic Diseases and Diabetes, Pisa University Hospital, Pisa, Italy
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Folli F, Okada T, Perego C, Gunton J, Liew CW, Akiyama M, D'Amico A, La Rosa S, Placidi C, Lupi R, Marchetti P, Sesti G, Hellerstein M, Perego L, Kulkarni RN. Altered insulin receptor signalling and β-cell cycle dynamics in type 2 diabetes mellitus. PLoS One 2011; 6:e28050. [PMID: 22140505 PMCID: PMC3227614 DOI: 10.1371/journal.pone.0028050] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 10/31/2011] [Indexed: 12/31/2022] Open
Abstract
Insulin resistance, reduced β-cell mass, and hyperglucagonemia are consistent features in type 2 diabetes mellitus (T2DM). We used pancreas and islets from humans with T2DM to examine the regulation of insulin signaling and cell-cycle control of islet cells. We observed reduced β-cell mass and increased α-cell mass in the Type 2 diabetic pancreas. Confocal microscopy, real-time PCR and western blotting analyses revealed increased expression of PCNA and down-regulation of p27-Kip1 and altered expression of insulin receptors, insulin receptor substrate-2 and phosphorylated BAD. To investigate the mechanisms underlying these findings, we examined a mouse model of insulin resistance in β-cells – which also exhibits reduced β-cell mass, the β-cell-specific insulin receptor knockout (βIRKO). Freshly isolated islets and β-cell lines derived from βIRKO mice exhibited poor cell-cycle progression, nuclear restriction of FoxO1 and reduced expression of cell-cycle proteins favoring growth arrest. Re-expression of insulin receptors in βIRKO β-cells reversed the defects and promoted cell cycle progression and proliferation implying a role for insulin-signaling in β-cell growth. These data provide evidence that human β- and α-cells can enter the cell-cycle, but proliferation of β-cells in T2DM fails due to G1-to-S phase arrest secondary to defective insulin signaling. Activation of insulin signaling, FoxO1 and proteins in β-cell-cycle progression are attractive therapeutic targets to enhance β-cell regeneration in the treatment of T2DM.
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Affiliation(s)
- Franco Folli
- Division of Diabetes, Department of Medicine, University of Texas Health Science Center, San Antonio, Texas, United States of America
- * E-mail: (RNK); (FF)
| | - Terumasa Okada
- Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Carla Perego
- Department of Molecular Science Applied to Biosystems, Università degli Studi di Milano, Milan, Italy
| | - Jenny Gunton
- Garvan Institute of Medical Research, Sydney, Australia
| | - Chong Wee Liew
- Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Masaru Akiyama
- Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Anna D'Amico
- Department of Molecular Science Applied to Biosystems, Università degli Studi di Milano, Milan, Italy
| | - Stefano La Rosa
- Department of Pathology, Ospedale di Circolo and Department of Human Morphology, University of Insubria, Varese, Italy
| | - Claudia Placidi
- Department of Pathology, Ospedale di Circolo and Department of Human Morphology, University of Insubria, Varese, Italy
| | - Roberto Lupi
- Division of Endocrinology, University of Pisa, Pisa, Italy
| | | | - Giorgio Sesti
- Department of Clinical and Experimental Medicine, University Magna Graecia of Catanzaro, Catanzaro, Italy
| | - Marc Hellerstein
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, California, United States of America
| | - Lucia Perego
- Department of Molecular Science Applied to Biosystems, Università degli Studi di Milano, Milan, Italy
| | - Rohit N. Kulkarni
- Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail: (RNK); (FF)
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Lencioni C, Resi V, Romero F, Lupi R, Volpe L, Bertolotto A, Ghio A, Del Prato S, Marchetti P, Di Cianni G. Glucagon-like peptide-1 secretion in women with gestational diabetes mellitus during and after pregnancy. J Endocrinol Invest 2011; 34:e287-90. [PMID: 21666414 DOI: 10.3275/7799] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
UNLABELLED Gestational diabetes mellitus (GDM) predisposes women to future development of Type 2 diabetes mellitus (DM2) and the two conditions share similar metabolic alterations. Recent observations suggest that a defective glucose stimulated insulin secretion by glucagon-like peptide-1 (GLP- 1) plays a role in the pathogenesis of DM2. Whether such a defect is impaired in GDM remains to be ascertained. AIM We have determined GLP-1 secretion in response to oral glucose tolerance test (OGTT) in GDM and normal glucose tolerance (NGT) during and after pregnancy. MATERIALS AND METHODS 100-g-3h OGTT was performed in 12 GDM and 16 NGT women at 27.3 ± 4.1 weeks of gestation, for determination of plasma GLP-1, glucose, insulin, and C-peptide. Insulin sensitivity (ISI) and insulin secretion (first and second phase); as well as ISI-secretion index (ISSI) were also derived. RESULTS NGT and GDM women were comparable for age pre-pregnancy body mass index (BMI) and weight gain. GDM had higher glucose area under the curve (AUC): 27,575.5 ± 3448 vs 20,685.88 ± 2715 mg/dl min (p<0.01), but lower first-phase insulin secretion (993.12±367 vs 1376.61 ± 423, p<0.05) and ISSI compared to controls (3873.23 ± 1185 vs 6232.13 ± 1734, p<0.001). When we examined GLP-1 mean levels in relation to mean glycemic values, GLP-1 secretion was inappropriately low with respect to mean glycemic values in GDM compared to NGT. At follow-up, AUCGLP-1 was significantly lower in post-partum GDM compared to post-partum NGT women (2542 ± 273 vs 10,092 ± 7367 pmol·l-1·min-1, p<0.05, respectively). CONCLUSIONS Our study suggests that GLP-1 secretion in GDM women is inadequate for the prevailing glycemic levels both in pregnancy and post partum. Moreover, we cannot exclude that other important aspects of the incretin effect may be involved in GDM development.
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Affiliation(s)
- C Lencioni
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
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D’Aleo V, Mancarella R, Del Guerra S, Boggi U, Filipponi F, Marchetti P, Lupi R. Direct effects of rapid-acting insulin analogues on insulin signaling in human pancreatic islets in vitro. Diabetes & Metabolism 2011; 37:324-9. [DOI: 10.1016/j.diabet.2010.12.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 11/16/2010] [Accepted: 12/15/2010] [Indexed: 10/18/2022]
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Larré C, Lupi R, Gombaud G, Brossard C, Branlard G, Moneret-Vautrin DA, Rogniaux H, Denery-Papini S. Assessment of allergenicity of diploid and hexaploid wheat genotypes: identification of allergens in the albumin/globulin fraction. J Proteomics 2011; 74:1279-89. [PMID: 21473946 DOI: 10.1016/j.jprot.2011.03.014] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Revised: 03/07/2011] [Accepted: 03/11/2011] [Indexed: 12/01/2022]
Abstract
Wheat is an important part of the daily diet of millions of people. However, this staple food is also responsible for food allergies. Ancient cultivars of wheat are gaining interest today but nothing is known about their allergenicity. Many wheat proteins have been reported as causative food allergens, including some prolamin-type gluten proteins, and salt soluble proteins of the albumin/globulin (A/G) type. The objective of this work is to obtain information about the allergenicity of the salt soluble A/G fraction of an ancient diploid cultivar compared with a standard hexaploid bread wheat cultivar using 20 sera from patients with wheat allergy. Differences in the IgE reactivity of sera towards the two genotypes were quantified by ELISA. Qualitative differences in IgE-binding proteins were searched after 1D or 2D electrophoresis. For most of the sera, the concentration in A/G specific IgE was higher for the hexaploid T. aestivum (cv Récital) than for the diploid T. monococcum (cv Engrain). The analysis of 2D spots revealed by immunoblotting leads to the identification by mass spectrometry of 39 IgE-binding proteins, some of them unknown until now as wheat allergens. Numerous allergens were identified, differences observed between Engrain and Récital will be discussed.
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Affiliation(s)
- C Larré
- UR1268 BIA, INRA, Rue de la Géraudière, BP 71627, 44316 Nantes, France.
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15
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Ardestani A, Sauter NS, Paroni F, Dharmadhikari G, Cho JH, Lupi R, Marchetti P, Oberholzer J, Conte JK, Maedler K. Neutralizing interleukin-1beta (IL-1beta) induces beta-cell survival by maintaining PDX1 protein nuclear localization. J Biol Chem 2011; 286:17144-55. [PMID: 21393239 DOI: 10.1074/jbc.m110.210526] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The transcription factor PDX1 plays a critical role during β-cell development and in glucose-induced insulin gene transcription in adult β-cells. Acute glucose exposure leads to translocalization of PDX1 to the nucleoplasm, whereas under conditions of oxidative stress, PDX1 shuttles from the nucleus to the cytosol. Here we show that cytosolic PDX1 expression correlated with β-cell failure in diabetes. In isolated islets from patients with type 2 diabetes and from diabetic mice, we found opposite regulation of insulin and PDX1 mRNA; insulin was decreased in diabetes, but PDX1 was increased. This suggests that elevated PDX1 mRNA levels may be insufficient to regulate insulin. In diabetic islets, PDX1 protein was localized in the cytosol, whereas in non-diabetic controls, PDX1 was in the nucleus. In contrast, overexpression of either IL-1 receptor antagonist or shuttling-deficient PDX1 restored β-cell survival and function and PDX1 nuclear localization. Our results show that nuclear localization of PDX1 is essential for a functional β-cell and provides a novel mechanism of the protective effect of IL-1 receptor antagonist on β-cell survival and function.
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Affiliation(s)
- Amin Ardestani
- Islet Biology Laboratory, Centre for Biomolecular Interactions Bremen 28355, University of Bremen, Leobener Strasse NW2, Rm. B2080, 28359 Bremen, Germany
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16
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D'Aleo V, Del Guerra S, Groves C, Lupi R, Tancredi M, McCarthy M, Marchetti P. INS VNTR class genotype and the function of isolated human islets. Nutr Metab Cardiovasc Dis 2011; 21:e9-e11. [PMID: 21193298 DOI: 10.1016/j.numecd.2010.10.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 09/21/2010] [Accepted: 10/18/2010] [Indexed: 11/21/2022]
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17
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Del Guerra S, D'Aleo V, Gualtierotti G, Filipponi F, Boggi U, De Simone P, Vistoli F, Del Prato S, Marchetti P, Lupi R. A common polymorphism in the monocyte chemoattractant protein-1 (MCP-1) gene regulatory region influences MCP-1 expression and function of isolated human pancreatic islets. Transplant Proc 2011; 42:2247-9. [PMID: 20692455 DOI: 10.1016/j.transproceed.2010.05.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND AIMS Islet transplantation is an attractive approach to treat type 1 diabetic patients. However, suboptimal islet engraftment still represents an unsolved problem. It has been shown that human islets release monocyte chemoattractant protein-1 (MCP-1), one of the most powerful macrophage chemokines, which may impair the fate of the transplant. The aim of this study was to evaluate the presence and role of MCP-1 in isolated human islets, including genotyping for a common polymorphism. METHODS Pancreatic islets were isolated by enzymatic digestion and gradient purification from 41 nondiabetic multiorgan donors. We measured MCP-1 mRNA expression by quantitative real- time reverse-transcriptase polymerization chain reaction, analyzed the MCP-1 single nucleotide polymorphism, -2518 G/A (SNP, rs 1024611) and evaluated glucose-stimulated insulin release (IR; microU/islet/min). RESULTS MCP-1 mRNA expression was found in all studied batches of islets. Overall, IR was significantly higher at 16.7 mmol/L than 3.3 mmol/L glucose. We observed a significant negative correlation between MCP-1 mRNA expression and stimulation index (SI). We found that MCP-1 mRNA expression was significantly higher in CC and CT compared with TT genotype groups. Finally, SI was significant lower in the CC with respect to the TT genotype group. CONCLUSIONS These data show that MCP-1 gene expression regulated by the -2518 G/A polymorphism, is correlated with glucose-stimulated insulin release. The study of MCP-1 expression and genotype on isolated islets before transplantation may be useful to understand the inflammatory response after infusion of human islets into patients with type 1 diabetes mellitus.
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Affiliation(s)
- S Del Guerra
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
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18
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Lupi R, Del Guerra S, D'Aleo V, Boggi U, Filipponi F, Marchetti P. The direct effects of GLP-1 and GIP, alone or in combination, on human pancreatic islets. ACTA ACUST UNITED AC 2010; 165:129-32. [DOI: 10.1016/j.regpep.2010.04.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Revised: 04/04/2010] [Accepted: 04/28/2010] [Indexed: 02/05/2023]
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19
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Montagnoli A, Rainoldi S, Sola F, Posteri H, Lupi R, Pesenti E, Donati D, Moll J, Pezzetta D, Papeo G. 520 NMS-P118, a Parp-1 selective inhibitor with efficacy in DNA repair deficient tumor models. EJC Suppl 2010. [DOI: 10.1016/s1359-6349(10)72227-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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20
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D'Aleo V, Del Guerra S, Gualtierotti G, Filipponi F, Boggi U, De Simone P, Vistoli F, Del Prato S, Marchetti P, Lupi R. Functional and Survival Analysis of Isolated Human Islets. Transplant Proc 2010; 42:2250-1. [DOI: 10.1016/j.transproceed.2010.05.132] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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21
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Cauchi S, Del Guerra S, Choquet H, D'Aleo V, Groves CJ, Lupi R, McCarthy MI, Froguel P, Marchetti P. Meta-analysis and functional effects of the SLC30A8 rs13266634 polymorphism on isolated human pancreatic islets. Mol Genet Metab 2010; 100:77-82. [PMID: 20138556 DOI: 10.1016/j.ymgme.2010.01.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2009] [Revised: 01/04/2010] [Accepted: 01/04/2010] [Indexed: 01/15/2023]
Abstract
BACKGROUND The C-allele of rs13266634 located in SLC30A8 (ZNT8) has been strongly associated with decreased insulin release and with type 2 diabetes (T2D) susceptibility in some but not all studies. To shed further light on this issue, we performed a meta-analysis of the association between rs13266634 and T2D in different ethnic groups and assessed the relationships between SLC30A8 genotypes and some properties of isolated human islets. METHODS From 32 original articles, a total of 77,234 control individuals and 44,945 subjects with T2D were studied in meta-analysis. To assess the relationships between SLC30A8 genotype and islet cell phenotype, insulin secretion in response to glucose, glucose plus arginine and glucose plus glibenclamide was determined in pancreatic islets isolated from 82 multiorgan donors genotyped for the rs13266634 polymorphism. Quantitative expression of SLC30A8, Insulin and Glucagon mRNA was also measured. RESULTS Overall, each SLC30A8 risk allele was associated with a 14% increased risk for T2D (P=2.78 x 10(-34)). The population risk of T2D attributable to this polymorphism was estimated at 9.5% in Europeans and 8.1% in East Asians. Basal and stimulated insulin secretion from human islets as well as islet expressions of SLC30A8, Insulin and Glucagon were not affected by the presence of the polymorphism. However, SLC30A8 expression was positively correlated with Insulin (r=0.75, P=6.43 x 10(-6)) and Glucagon (r: 0.70, P=4.89 x 10(-5)) levels. CONCLUSIONS The SLC30A8 rs13266634 polymorphism is among the most confirmed genetic markers of T2D in Europeans and East Asians. In isolated human islets, the risk C-allele does not affect ex-vivo insulin secretion and SLC30A8 expression, which is correlated with that of insulin and glucagon.
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Affiliation(s)
- Stéphane Cauchi
- CNRS UMR 8090, Institute of Biology, Genomics and Molecular Physiology of Metabolic Diseases, Lille, France
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22
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Marchetti P, Lupi R, Del Guerra S, Bugliani M, Marselli L, Boggi U. The β-Cell in Human Type 2 Diabetes. Advances in Experimental Medicine and Biology 2010; 654:501-14. [DOI: 10.1007/978-90-481-3271-3_22] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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23
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Del Guerra S, Bugliani M, D'Aleo V, Del Prato S, Boggi U, Mosca F, Filipponi F, Lupi R. G-protein-coupled receptor 40 (GPR40) expression and its regulation in human pancreatic islets: the role of type 2 diabetes and fatty acids. Nutr Metab Cardiovasc Dis 2010; 20:22-25. [PMID: 19758793 DOI: 10.1016/j.numecd.2009.02.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 10/13/2008] [Accepted: 02/16/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND AND AIMS GPR40 is a membrane-bound receptor paired with medium and long-chain fatty acids (FFA) as endogenous ligands. Its acute activation potentiates insulin secretion from beta cells, whereas prolonged binding might contribute to the deleterious effects of chronic exposure to FFA. Little information is available on the expression of GPR40 and its regulation in human islets (HI). MATERIAL AND METHODS HI were prepared by enzymatic digestion and gradient separation from the pancreas of 20 non-diabetic (Ctrl) and 13 type 2 diabetic (T2DM) multiorgan donors, and functional and molecular studies were then performed. RESULTS By qualitative and quantitative PCR experiments, mRNA expression was shown in HI. Both in T2DM islets and in Ctrl islets pre-exposed for 24 h to 1.0 mmol/l FFA (palmitate:oleate, 2:1), GPR40 mRNA expression was significantly reduced (p<0.01) in the T2DM cells as compared to Ctrl cells. A significant positive correlation was found between glucose-stimulated insulin secretion and GPR40 expression. CONCLUSIONS These results show the expression of GPR40 in human pancreatic islets which are regulated by FFA. The finding that T2DM islets have a lower GPR40 expression, and the correlation of these genes with insulin secretion, raises the possibility of an involvement of GPR40 in human diabetes beta-cell dysfunction.
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Affiliation(s)
- S Del Guerra
- University of Pisa, Dip. Endocrinologia e Metabolismo, Sezione Metabolismo, Ospedale Cisanello, Via Paradisa 2, 56124 Pisa - Italy
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24
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Cunha DA, Ladrière L, Ortis F, Igoillo-Esteve M, Gurzov EN, Lupi R, Marchetti P, Eizirik DL, Cnop M. Glucagon-like peptide-1 agonists protect pancreatic beta-cells from lipotoxic endoplasmic reticulum stress through upregulation of BiP and JunB. Diabetes 2009; 58:2851-62. [PMID: 19720788 PMCID: PMC2780890 DOI: 10.2337/db09-0685] [Citation(s) in RCA: 175] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Chronic exposure of pancreatic beta-cells to saturated free fatty acids (FFAs) causes endoplasmic reticulum (ER) stress and apoptosis and may contribute to beta-cell loss in type 2 diabetes. Here, we evaluated the molecular mechanisms involved in the protection of beta-cells from lipotoxic ER stress by glucagon-like peptide (GLP)-1 agonists utilized in the treatment of type 2 diabetes. RESEARCH DESIGN AND METHODS INS-1E or fluorescence-activated cell sorter-purified primary rat beta-cells were exposed to oleate or palmitate with or without the GLP-1 agonist exendin-4 or forskolin. Cyclopiazonic acid was used as a synthetic ER stressor, while the activating transcription factor 4-C/EBP homologous protein branch was selectively activated with salubrinal. The ER stress signaling pathways modulated by GLP-1 agonists were studied by real-time PCR and Western blot. Knockdown by RNA interference was used to identify mediators of the antiapoptotic GLP-1 effects in the ER stress response and downstream mitochondrial cell death mechanisms. RESULTS Exendin-4 and forskolin protected beta-cells against FFAs via the induction of the ER chaperone BiP and the antiapoptotic protein JunB that mediate beta-cell survival under lipotoxic conditions. On the other hand, exendin-4 and forskolin protected against synthetic ER stressors by inactivating caspase 12 and upregulating Bcl-2 and X-chromosome-linked inhibitor of apoptosis protein that inhibit mitochondrial apoptosis. CONCLUSIONS These observations suggest that GLP-1 agonists increase in a context-dependent way the beta-cell defense mechanisms against different pathways involved in ER stress-induced apoptosis. The identification of the pathways modulated by GLP-1 agonists allows for targeted approaches to alleviate beta-cell ER stress in diabetes.
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Affiliation(s)
- Daniel A. Cunha
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Laurence Ladrière
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Fernanda Ortis
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | | | - Esteban N. Gurzov
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Roberto Lupi
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Décio L. Eizirik
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
| | - Miriam Cnop
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
- Division of Endocrinology, Erasmus Hospital, Brussels, Belgium
- Corresponding author: Miriam Cnop,
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25
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Marchetti P, Lupi R, Del Guerra S, Bugliani M, D'Aleo V, Occhipinti M, Boggi U, Marselli L, Masini M. Goals of treatment for type 2 diabetes: beta-cell preservation for glycemic control. Diabetes Care 2009; 32 Suppl 2:S178-83. [PMID: 19875548 PMCID: PMC2811441 DOI: 10.2337/dc09-s306] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Piero Marchetti
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy.
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26
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D'Aleo V, Del Guerra S, Martano M, Bonamassa B, Canistro D, Soleti A, Valgimigli L, Paolini M, Filipponi F, Boggi U, Del Prato S, Lupi R. The non-peptidyl low molecular weight radical scavenger IAC protects human pancreatic islets from lipotoxicity. Mol Cell Endocrinol 2009; 309:63-6. [PMID: 19481137 DOI: 10.1016/j.mce.2009.05.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2009] [Revised: 05/15/2009] [Accepted: 05/19/2009] [Indexed: 11/22/2022]
Abstract
BACKGROUND Chronic exposure to high free fatty acids (FFA) can lead to irreversible damage of beta-cell accounting for impaired insulin secretion. Multiple mechanisms concur in generating the damage, but activation of oxidative stress may contribute to the final toxic effect. To better understand the phenomenon of lipotoxicity in human beta-cells, we evaluated the effects of 24-h pre-culture with 1.0 mmol/l FFA on the function, survival and mRNA expression of several enzymes involved in the generation and scavenging of reactive oxygen species (ROS). MATERIAL AND METHODS Human islets, prepared by collagenase digestion and density gradient purification from 9 pancreases of multiorgan donors, were incubated for 24-h in the presence 1.0 mmol/l long-chain mixture (oleate:palmitate, 2:1) FFA, with or without 100 micromol/l IAC, a non-peptidyl low molecular weight radical scavenger. At the end of incubation period, insulin secretion was measured by static incubation, and mRNA expression of insulin, Cu/Zn-SOD, Mn-SOD, Catalase, Glutathione peroxidase (GSH-px) and HO-1 by quantitative Real-Time RT-PCR. Nitrotyrosine levels were determined by an ELISA technique. RESULTS As compared to control incubation (Ctrl, no FFA), exposure to FFA was associated with impaired insulin release and reduced insulin mRNA expression. The presence of IAC in the incubation medium increased insulin release significantly and prevented changes in mRNA expression. Exposure to FFA was associated with oxidative stress as indicated by a significant accumulation of nitrotyrosine and IAC restrained such an increase. mRNA expression of Cu/Zn-SOD, Mn-SOD, Catalase, GSH-Px, and HO-1 were all modified after FFA exposure. These changes were partially prevented in the presence of IAC. CONCLUSIONS In human islets 24-h exposure to high FFA causes oxidative stress associated with changes of several enzymes involved in ROS scavenging. These effects were prevented by the use of an antioxidant molecule.
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Affiliation(s)
- Valentina D'Aleo
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Italy
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27
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Abstract
Autophagy is a vacuolar, self-digesting mechanism responsible for the removal of organelles and defined regions of the cytoplams. This process has, in general, a beneficial role for the cell, since it regulates the turnover of aged proteins and eliminates damaged structures. However, cells that undergo altered autophagy may be triggered to die in a non-apoptotic manner. As a matter of fact, in recent years it has become clear that dysregulated autophagy may be implicated in several disorders, such as cancer, neurodegenerative diseases and hepatic encephalopathy. We have recently shown that β-cells of type 2 diabetic subjects show signs of autophagy associated death, which may contribute to the overall loss of β-cell mass in type 2 diabetes. In addition, studies with cell lines and rodent models have demonstrated the importance of autophagy in β-cell function and survival. Altogether, the available evidence supports the view that autophagy is implicated in β-cell pathophysiology, and suggests that addressing the molecular mechanisms involved in autophagic regulation might provide clues for preventing or treating β-cell damage in diabetes.
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Affiliation(s)
- Matilde Masini
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
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28
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Del Guerra S, D’Aleo V, Lupi R, Masini M, Bugliani M, Boggi U, Filipponi F, Marchetti P. Effects of exposure of human islet beta-cells to normal and high glucose levels with or without gliclazide or glibenclamide. Diabetes & Metabolism 2009; 35:293-8. [DOI: 10.1016/j.diabet.2009.01.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2008] [Revised: 01/02/2009] [Accepted: 01/06/2009] [Indexed: 11/15/2022]
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Ling C, Groop L, Guerra SD, Lupi R. Calpain-10 expression is elevated in pancreatic islets from patients with type 2 diabetes. PLoS One 2009; 4:e6558. [PMID: 19688040 PMCID: PMC2719809 DOI: 10.1371/journal.pone.0006558] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 01/07/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Calpain-10 was the first gene to be identified influencing the risk of type 2 diabetes (T2D) by positioning cloning. Studies in beta-cell lines and rodent islets suggest that calpain-10 may act as a regulator of insulin secretion. However, its role in human pancreatic islets remains unclear. The aim of this study was to examine if calpain-10 expression is altered in islets from patients with T2D and if the transcript level correlates with insulin release. We also tested if polymorphisms in the CAPN10 gene are associated with gene expression and insulin secretion in vitro. METHODOLOGY/PRINCIPAL FINDINGS Calpain-10 mRNA expression was analysed in human pancreatic islets from 34 non-diabetic and 10 T2D multi-organ donors. CAPN10 SNP-43 and SNP-44 were genotyped and related to gene expression and insulin release in response to glucose, arginine and glibenclamide. The mRNA level of calpain-10 was elevated by 64% in pancreatic islets from patients with T2D compared with non-diabetic donors (P = 0.01). Moreover, the calpain-10 expression correlated positively with arginine-stimulated insulin release in islets from non-diabetic donors (r = 0.45, P = 0.015). However, this correlation was lost in islets from patients with T2D (r = 0.09; P = 0.8). The G/G variant of SNP-43 was associated with reduced insulin release in response to glucose (P</=0.04) in non-diabetic donors. CONCLUSIONS While calpain-10 expression correlates with insulin release in non-diabetic human islets, this correlation is lost in T2D suggesting that a stimulatory effect of calpain-10 could be lost in patients with T2D.
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Affiliation(s)
- Charlotte Ling
- Department of Clinical Sciences, Diabetes and Endocrinology, Lund University, Clinical Research Centre (CRC), Malmö, Sweden.
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30
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Borg J, Klint C, Wierup N, Ström K, Larsson S, Sundler F, Lupi R, Marchetti P, Xu G, Kimmel A, Londos C, Holm C. Perilipin is present in islets of Langerhans and protects against lipotoxicity when overexpressed in the beta-cell line INS-1. Endocrinology 2009; 150:3049-57. [PMID: 19299455 PMCID: PMC2703509 DOI: 10.1210/en.2008-0913] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Lipids have been shown to play a dual role in pancreatic beta-cells: a lipid-derived signal appears to be necessary for glucose-stimulated insulin secretion, whereas lipid accumulation causes impaired insulin secretion and apoptosis. The ability of the protein perilipin to regulate lipolysis prompted an investigation of the presence of perilipin in the islets of Langerhans. In this study evidence is presented for perilipin expression in rat, mouse, and human islets of Langerhans as well as the rat clonal beta-cell line INS-1. In rat and mouse islets, perilipin was verified to be present in beta-cells. To examine whether the development of lipotoxicity could be prevented by manipulating the conditions for lipid storage in the beta-cell, INS-1 cells with adenoviral-mediated overexpression of perilipin were exposed to lipotoxic conditions for 72 h. In cells exposed to palmitate, perilipin overexpression caused increased accumulation of triacylglycerols and decreased lipolysis compared with control cells. Whereas glucose-stimulated insulin secretion was retained after palmitate exposure in cells overexpressing perilipin, it was completely abolished in control beta-cells. Thus, overexpression of perilipin appears to confer protection against the development of beta-cell dysfunction after prolonged exposure to palmitate by promoting lipid storage and limiting lipolysis.
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Affiliation(s)
- Jörgen Borg
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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31
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Masini M, Bugliani M, Lupi R, del Guerra S, Boggi U, Filipponi F, Marselli L, Masiello P, Marchetti P. Autophagy in human type 2 diabetes pancreatic beta cells. Diabetologia 2009; 52:1083-6. [PMID: 19367387 DOI: 10.1007/s00125-009-1347-2] [Citation(s) in RCA: 264] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Accepted: 03/06/2009] [Indexed: 12/13/2022]
Abstract
AIMS/HYPOTHESIS Beta cell loss contributes to type 2 diabetes, with increased apoptosis representing an underlying mechanism. Autophagy, i.e. the physiological degradation of damaged organelles and proteins, may, if altered, be associated with a distinct form of cell death. We studied several features of autophagy in beta cells from type 2 diabetic patients and assessed the role of metabolic perturbation and pharmacological intervention. METHODS Pancreatic samples were obtained from organ donors and isolated islets prepared both by collagenase digestion and density gradient centrifugation. Beta cell morphology and morphometry were studied by electron microscopy. Gene expression studies were performed by quantitative RT-PCR. RESULTS Using electron microscopy, we observed more dead beta cells in diabetic (2.24 +/- 0.53%) than control (0.66 +/- 0.52%) samples (p < 0.01). Massive vacuole overload (suggesting altered autophagy) was associated with 1.18 +/- 0.54% dead beta cells in type 2 diabetic samples and with 0.36 +/- 0.26% in control samples (p < 0.05). Density volume of autophagic vacuoles and autophagosomes was significantly higher in diabetic beta cells. Unchanged gene expression of beclin-1 and ATG1 (also known as ULK1), and reduced transcription of LAMP2 and cathepsin B and D was observed in type 2 diabetic islets. Exposure of non-diabetic islets to increased NEFA concentration led to a marked increase of vacuole accumulation, together with enhanced beta cell death, which was associated with decreased LAMP2 expression. Metformin ameliorated autophagy alterations in diabetic beta cells and beta cells exposed to NEFA, a process associated with normalisation of LAMP2 expression. CONCLUSIONS/INTERPRETATION Beta cells in human type 2 diabetes have signs of altered autophagy, which may contribute to loss of beta cell mass. To preserve beta cell mass in diabetic patients, it may be necessary to target multiple cell-death pathways.
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Affiliation(s)
- M Masini
- Department of Experimental Pathology, University of Pisa, Pisa, Italy
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Del Guerra S, Lupi R, D'Aleo V, Filipponi F, Boggi U, Marchetti P. Glucose transporter 2 gene polymorphisms and beta-cell function in isolated human pancreatic islets. Diabetes Metab 2009; 35:155-6. [PMID: 19269875 DOI: 10.1016/j.diabet.2009.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2009] [Accepted: 01/20/2009] [Indexed: 11/26/2022]
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Serre-Beinier V, Bosco D, Zulianello L, Charollais A, Caille D, Charpantier E, Gauthier BR, Diaferia GR, Giepmans BN, Lupi R, Marchetti P, Deng S, Buhler L, Berney T, Cirulli V, Meda P. Cx36 makes channels coupling human pancreatic beta-cells, and correlates with insulin expression. Hum Mol Genet 2009; 18:428-39. [PMID: 19000992 PMCID: PMC2638800 DOI: 10.1093/hmg/ddn370] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Previous studies have documented that the insulin-producing beta-cells of laboratory rodents are coupled by gap junction channels made solely of the connexin36 (Cx36) protein, and have shown that loss of this protein desynchronizes beta-cells, leading to secretory defects reminiscent of those observed in type 2 diabetes. Since human islets differ in several respects from those of laboratory rodents, we have now screened human pancreas, and islets isolated thereof, for expression of a variety of connexin genes, tested whether the cognate proteins form functional channels for islet cell exchanges, and assessed whether this expression changes with beta-cell function in islets of control and type 2 diabetics. Here, we show that (i) different connexin isoforms are differentially distributed in the exocrine and endocrine parts of the human pancreas; (ii) human islets express at the transcript level different connexin isoforms; (iii) the membrane of beta-cells harbors detectable levels of gap junctions made of Cx36; (iv) this protein is concentrated in lipid raft domains of the beta-cell membrane where it forms gap junctions; (v) Cx36 channels allow for the preferential exchange of cationic molecules between human beta-cells; (vi) the levels of Cx36 mRNA correlated with the expression of the insulin gene in the islets of both control and type 2 diabetics. The data show that Cx36 is a native protein of human pancreatic islets, which mediates the coupling of the insulin-producing beta-cells, and contributes to control beta-cell function by modulating gene expression.
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Affiliation(s)
| | - Domenico Bosco
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Laurence Zulianello
- Department of Cell Physiology and Metabolism, University of Geneva School of Medicine, CMU 1, rue Michel-Servet, 1211 Geneva 4, CH, Switzerland
| | - Anne Charollais
- Department of Cell Physiology and Metabolism, University of Geneva School of Medicine, CMU 1, rue Michel-Servet, 1211 Geneva 4, CH, Switzerland
| | - Dorothée Caille
- Department of Cell Physiology and Metabolism, University of Geneva School of Medicine, CMU 1, rue Michel-Servet, 1211 Geneva 4, CH, Switzerland
| | - Eric Charpantier
- Department of Cell Physiology and Metabolism, University of Geneva School of Medicine, CMU 1, rue Michel-Servet, 1211 Geneva 4, CH, Switzerland
| | - Benoit R. Gauthier
- Department of Cell Physiology and Metabolism, University of Geneva School of Medicine, CMU 1, rue Michel-Servet, 1211 Geneva 4, CH, Switzerland
| | - Giuseppe R. Diaferia
- Islet Research Laboratory, The Whittier Institute for Diabetes, University of California San Diego, La Jolla, CA, USA
| | - Ben N. Giepmans
- Department of Cell Biology, University of Groningen, Groningen, The Netherlands
| | - Roberto Lupi
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy
| | - Shaoping Deng
- Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Léo Buhler
- Surgical Research Unit, Department of Surgery
| | - Thierry Berney
- Cell Isolation and Transplantation Center, Department of Surgery, Geneva University Hospitals, Geneva, Switzerland
| | - Vincenzo Cirulli
- Islet Research Laboratory, The Whittier Institute for Diabetes, University of California San Diego, La Jolla, CA, USA
| | - Paolo Meda
- Department of Cell Physiology and Metabolism, University of Geneva School of Medicine, CMU 1, rue Michel-Servet, 1211 Geneva 4, CH, Switzerland
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Santini E, Lupi R, Baldi S, Madec S, Chimenti D, Ferrannini E, Solini A. Effects of different LDL particles on inflammatory molecules in human mesangial cells. Diabetologia 2008; 51:2117-25. [PMID: 18751966 DOI: 10.1007/s00125-008-1127-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2008] [Accepted: 07/15/2008] [Indexed: 10/21/2022]
Abstract
AIMS/HYPOTHESIS Inflammation is a mechanism of glomerular damage in chronic glomerulopathies. LDL may increase the production of inflammatory cytokines in renal tissues. However, the relative role of native, oxidised and glycated LDL in promoting this process has been only partially elucidated. METHODS We tested the inflammatory and proapoptotic effects of native, oxidised and glycated LDL in human mesangial cells (HMCs) by measuring levels of IL6, CD40 and macrophage migration inhibitory factor (MIF) genes, MIF protein, release of IL6, soluble CD40, fibronectin and laminin, early and late apoptosis, and extracellular regulated kinases (ERK) 1/2 and c-Jun N-terminal kinase (JNK) activation. RESULTS IL6 and CD40 mRNA were dose-dependently upregulated by all three species; this was closely paralleled by their increased release. MIF mRNA was potently stimulated by modified LDL, as confirmed by immunostaining. Fibronectin and laminin release was stimulated by both oxidised and glycated, but not native, LDL. All LDL species induced some increase in late, but not early, apoptosis, and similarly activated JNK2/3 phosphorylation; in contrast, ERK1/2 phosphorylation was more strongly upregulated by oxidised than either native or glycated LDL. CONCLUSIONS In HMCs, the production and release of IL6 and CD40 is stimulated by both native and modified LDL, while MIF is more strongly stimulated by oxidised LDL. Regarding the pattern of mesangial expansion, fibronectin and laminin are upregulated by oxidised and glycated LDL. Apoptosis, if modest, is induced by all species. Intracellular signalling of native and modified LDL involves JNK2/3 and, perhaps more specifically, ERK1/2. Tight control of the lipid profile may be useful in preserving kidney function in patients with metabolic alterations.
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Affiliation(s)
- E Santini
- Department of Internal Medicine, University of Pisa, Via Roma 67, I-56100, Pisa, Italy
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Mancarella R, Del Guerra S, Masini M, Bugliani M, Valgimigli L, Pedulli GF, Paolini M, Canistro D, Armando A, Soleti A, Filipponi F, Mosca F, Boggi U, Del Prato S, Marchetti P, Lupi R. Beneficial Effect of the Nonpeptidyl Low Molecular Weight Radical Scavenger IAC on Cultured Human Islet Function. Cell Transplant 2008; 17:1271-6. [DOI: 10.3727/096368908787236639] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We examined a possible protective effect of the nonpeptidyl low molecular weight radical scavenger IAC [bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)decanedioate di-hydrochloride] on isolated human islet cells against isolation and culture oxidative stress. Islets isolated from pancreases of nondiabetic multiorgan donors by collagenase digestion were purified by density gradient centrifugation. After the isolation, islets were either exposed or not exposed for 7 days to 10 μmol/L IAC. We found that IAC markedly reduced oxidative stress and ameliorated islets function. These results suggest that the use of IAC could be an interesting pharmacological approach for the treatment of the islets before transplantation.
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Affiliation(s)
- Rita Mancarella
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Silvia Del Guerra
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Matilde Masini
- Department of Experimental Pathology, University of Pisa, Pisa, Italy
| | - Marco Bugliani
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Luca Valgimigli
- Department of Organic Chemistry “A. Mangini”, University of Bologna, Bologna, Italy
| | - Gian Franco Pedulli
- Department of Organic Chemistry “A. Mangini”, University of Bologna, Bologna, Italy
| | - Moreno Paolini
- Department of Pharmacology, Molecular Toxicology Unit, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | - Donatella Canistro
- Department of Pharmacology, Molecular Toxicology Unit, Alma Mater Studiorum, University of Bologna, Bologna, Italy
| | | | | | - Franco Filipponi
- Department of Oncology and Transplant Surgery, University of Pisa, Pisa, Italy
| | - Franco Mosca
- Department of Oncology and Transplant Surgery, University of Pisa, Pisa, Italy
| | - Ugo Boggi
- Department of Oncology and Transplant Surgery, University of Pisa, Pisa, Italy
| | - Stefano Del Prato
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Piero Marchetti
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
| | - Roberto Lupi
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
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Abstract
Type 2 diabetes, the most common form of diabetes in humans, is characterized by impaired insulin secretion paralleled by a progressive decline in beta-cell function and chronic insulin resistance. Several authors have showed that in type 2 diabetes there is a reduction of islet and/or insulin-containing cell mass or volume. Regulation of the beta-cell mass appears to involve a balance of beta-cell replication and apoptosis but, at the molecular level, pancreatic beta-cell loss by apoptosis appears to play an important role in the development of insulin deficiency and the onset and/or progression of the disease. The mechanisms favoring apoptosis in type 2 diabetic pancreatic islets and new potential therapeutic approaches to prevent beta-cell death and maintain beta-cell mass are discussed.
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Affiliation(s)
- R Lupi
- Department of Endocrinology and Metabolism, Section of Diabetes and Metabolic Diseases, University of Pise, Italy
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Falchetti M, Rizzolo P, Lupi R, Ceccarelli K, Masala G, Saieva C, Zanna I, Matullo G, Palli D, Ottini L. DNA repair and metabolic gene polymorphisms and male breast cancer risk. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71550-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Rizzolo P, Falchetti M, Lupi R, Ceccarelli K, Silvestri V, Masala G, Saieva C, Zanna I, Palli D, Ottini L. BRCA1/BRCA2 mutation profile and phenotypic features of male breast cancer: a population-based study in Italy. EJC Suppl 2008. [DOI: 10.1016/s1359-6349(08)71337-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Cunha DA, Hekerman P, Ladrière L, Bazarra-Castro A, Ortis F, Wakeham MC, Moore F, Rasschaert J, Cardozo AK, Bellomo E, Overbergh L, Mathieu C, Lupi R, Hai T, Herchuelz A, Marchetti P, Rutter GA, Eizirik DL, Cnop M. Initiation and execution of lipotoxic ER stress in pancreatic beta-cells. J Cell Sci 2008; 121:2308-18. [PMID: 18559892 DOI: 10.1242/jcs.026062] [Citation(s) in RCA: 457] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Free fatty acids (FFA) cause apoptosis of pancreatic beta-cells and might contribute to beta-cell loss in type 2 diabetes via the induction of endoplasmic reticulum (ER) stress. We studied here the molecular mechanisms implicated in FFA-induced ER stress initiation and apoptosis in INS-1E cells, FACS-purified primary beta-cells and human islets exposed to oleate and/or palmitate. Treatment with saturated and/or unsaturated FFA led to differential ER stress signaling. Palmitate induced more apoptosis and markedly activated the IRE1, PERK and ATF6 pathways, owing to a sustained depletion of ER Ca(2+) stores, whereas the unsaturated FFA oleate led to milder PERK and IRE1 activation and comparable ATF6 signaling. Non-metabolizable methyl-FFA analogs induced neither ER stress nor beta-cell apoptosis. The FFA-induced ER stress response was not modified by high glucose concentrations, suggesting that ER stress in primary beta-cells is primarily lipotoxic, and not glucolipotoxic. Palmitate, but not oleate, activated JNK. JNK inhibitors reduced palmitate-mediated AP-1 activation and apoptosis. Blocking the transcription factor CHOP delayed palmitate-induced beta-cell apoptosis. In conclusion, saturated FFA induce ER stress via ER Ca(2+) depletion. The IRE1 and resulting JNK activation contribute to beta-cell apoptosis. PERK activation by palmitate also contributes to beta-cell apoptosis via CHOP.
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Affiliation(s)
- Daniel A Cunha
- Laboratory of Experimental Medicine, Université Libre de Bruxelles, Brussels, Belgium
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Abstract
Diabetes mellitus has been defined as a "group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both" and encompasses a wide range of heterogeneous conditions. Common type 2 diabetes mellitus (T2DM) results from a combination of genetic and acquired factors. However, lifestyle factors, particularly overeating and physical inactivity, are the major clinical determinants of T2DM. Insulin resistance is a common feature of T2DM, but it is unlikely to cause T2DM unless progressive loss of beta-cell function develops. Significant reduction in beta-cell function is already present at the time of T2DM diagnosis, and it continuously declines irrespective of treatment. As such, the progressive loss of beta-cell function dictates the rate of worsened glycemic control. Development of progressive deterioration accelerates via gluco- and lipotoxicity, loss of beta-cell function, and shrinkage of beta-cell mass. Understanding the causes for beta-cell failure is therefore of capital importance to develop new and more effective therapeutic strategies.
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Affiliation(s)
- Cristina Lencioni
- Department of Endocrinology and Metabolism, Section of Diabetes and Metabolic Diseases, University of Pisa, Ospedale Cisanello, Via Paradisa, 2, 56124 Pisa, Italy
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Lupi R, Mancarella R, Del Guerra S, Bugliani M, Del Prato S, Boggi U, Mosca F, Filipponi F, Marchetti P. Effects of exendin-4 on islets from type 2 diabetes patients. Diabetes Obes Metab 2008; 10:515-9. [PMID: 18201204 DOI: 10.1111/j.1463-1326.2007.00838.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Exendin-4 is a dipeptidyl peptidase IV (DPP-IV)-resistant glucagon-like peptide 1 (GLP-1) mimetic and its synthetic counterpart, exenatide, is being used in the therapy of type 2 diabetes (T2DM). No information, however, is currently available as for the direct action of exendin-4 on human T2DM islets. In the present study, we exposed pancreatic islets prepared from non-diabetic and T2DM subjects to exendin-4 for 48 h and found that the compound had several, direct beneficial actions on insulin secretion and the expression of genes involved in beta-cell function and differentiation.
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Ling C, Del Guerra S, Lupi R, Rönn T, Granhall C, Luthman H, Masiello P, Marchetti P, Groop L, Del Prato S. Epigenetic regulation of PPARGC1A in human type 2 diabetic islets and effect on insulin secretion. Diabetologia 2008; 51:615-22. [PMID: 18270681 PMCID: PMC2270364 DOI: 10.1007/s00125-007-0916-5] [Citation(s) in RCA: 317] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Accepted: 12/10/2007] [Indexed: 12/15/2022]
Abstract
AIMS/HYPOTHESIS Insulin secretion in pancreatic islets is dependent upon mitochondrial function and production of ATP. The transcriptional coactivator peroxisome proliferator activated receptor gamma coactivator-1 alpha (protein PGC-1alpha; gene PPARGC1A) is a master regulator of mitochondrial genes and its expression is decreased and related to impaired oxidative phosphorylation in muscle from patients with type 2 diabetes. Whether it plays a similar role in human pancreatic islets is not known. We therefore investigated if PPARGC1A expression is altered in islets from patients with type 2 diabetes and whether this expression is influenced by genetic (PPARGC1A Gly482Ser polymorphism) and epigenetic (DNA methylation) factors. We also tested if experimental downregulation of PPARGC1A expression in human islets influenced insulin secretion. METHODS The PPARGC1A Gly482Ser polymorphism was genotyped in human pancreatic islets from 48 non-diabetic and 12 type 2 diabetic multi-organ donors and related to PPARGC1A mRNA expression. DNA methylation of the PPARGC1A promoter was analysed in pancreatic islets from ten type 2 diabetic and nine control donors. Isolated human islets were transfected with PPARGC1A silencing RNA (siRNA). RESULTS PPARGC1A mRNA expression was reduced by 90% (p<0.005) and correlated with the reduction in insulin secretion in islets from patients with type 2 diabetes. After downregulation of PPARGC1A expression in human islets by siRNA, insulin secretion was reduced by 41% (p <or= 0. 01). We were able to ascribe reduced PPARGC1A expression in islets to both genetic and epigenetic factors, i.e. a common PPARGC1A Gly482Ser polymorphism was associated with reduced PPARGC1A mRNA expression (p<0.00005) and reduced insulin secretion (p<0.05). In support of an epigenetic influence, the PPARGC1A gene promoter showed a twofold increase in DNA methylation in diabetic islets compared with non-diabetic islets (p<0.04). CONCLUSIONS/INTERPRETATION We have shown for the first time that PPARGC1A might be important in human islet insulin secretion and that expression of PPARGC1A in human islets can be regulated by both genetic and epigenetic factors.
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Affiliation(s)
- C Ling
- Department of Clinical Sciences, Diabetes and Endocrinology, Lund University, CRC, 205 02 Malmö, Sweden.
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Ottini L, Falchetti M, Lupi R, Rizzolo P, Agnese V, Colucci G, Bazan V, Russo A. Patterns of genomic instability in gastric cancer: clinical implications and perspectives. Ann Oncol 2008; 17 Suppl 7:vii97-102. [PMID: 16760303 DOI: 10.1093/annonc/mdl960] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In gastric cancer (GC) the loss of genomic stability represents a key molecular step that occurs early in the carcinogenesis process and creates a permissive environment for the accumulation of genetic and epigenetic alterations in tumor suppressor genes and oncogenes. It is widely accepted that GC can follow at least two major genomic instability pathways, microsatellite instability (MSI) and chromosome instability (CIN). MSI is responsible for a well-defined subset of GCs. CIN represents a more common pathway comprising heterogeneous subsets of GC. In addition to MSI and CIN, the CpG islands methylator phenotype (CIMP) plays an important role in gastric carcinogenesis. CIMP may lead to the transcriptional silencing of various genes in gastric carcinogenesis. Intriguingly, more recently in addition to CpG island hypermethylation, a global DNA demethylation, that precedes genomic damage, has been observed in GC. Thus, epigenetic alterations may play a relevant role in gastric carcinogenesis as alternative mechanisms. Evidence suggests that although MSI, CIN and CIMP phenotypes can be distinguished from one another, there might be some degree of overlap. This review describes our current knowledge of the instability pathways in gastric carcinogenesis and the potential clinical applications for different forms of genomic instability in GC.
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Affiliation(s)
- L Ottini
- Department of Experimental Medicine and Pathology, University La Sapienza, Rome
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Menegazzi M, Novelli M, Beffy P, D'Aleo V, Tedeschi E, Lupi R, Zoratti E, Marchetti P, Suzuki H, Masiello P. Protective effects of St. John's wort extract and its component hyperforin against cytokine-induced cytotoxicity in a pancreatic beta-cell line. Int J Biochem Cell Biol 2007; 40:1509-21. [PMID: 18226577 DOI: 10.1016/j.biocel.2007.11.019] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 11/16/2007] [Accepted: 11/20/2007] [Indexed: 10/22/2022]
Abstract
In both type 1 and type 2 diabetes, increased production of cytokines on autoimmune or metabolic basis is supposed to trigger an inflammatory process leading to dysfunction and death of pancreatic beta-cells. Therefore, anti-inflammatory pharmacological approaches aimed at blocking cytokine signalling pathways and consequent cytotoxicity in beta-cells are highly advisable. Based on previous evidence of cytokine antagonistic effects in other cell types, we explored the protective action of Hypericum perforatum (St-John's-wort) extract and its component hyperforin against cytokine-induced functional impairment and apoptosis in the INS-1E beta-cell line, searching for the underlying mechanisms. The results showed that either St-John's-wort extract or hyperforin (at 1-3 microM) prevented cytokine-induced impairment in glucose-stimulated insulin secretion and protected cells against apoptosis in a dose-dependent fashion. Inducible-NO-synthase expression was also potently hindered by the vegetal compounds. Interestingly, cytokine-induced activations of the signal-transducer-and-activator-of-transcription-1 (STAT-1) and the nuclear-factor-kappaB (NF-kappaB) were both down-regulated by SJW extract or HPF (range 0.5-5 microM) when evaluated by electrophoretic-mobility-shift-assay. Other transcription factors (CBF-1, SP-1) were unaffected. Components of SJW extract other than HPF were much less effective in down-regulating cytokine signalling. Significantly, inhibition of cytokine-elicited STAT-1 and NF-kappaB activation was confirmed in isolated rat and human islets incubated in the presence of these vegetal compounds. In conclusion, St-John's-wort extract and hyperforin are non-peptidyl compounds which, at low concentrations, target key mechanisms of cytokine-induced beta-cell injury, thereby improving beta-cell function and survival. Thus, they are potentially valuable for the prevention or limitation of beta-cell loss in diabetes.
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Affiliation(s)
- Marta Menegazzi
- Dipartimento di Scienze Morfologiche e Biomediche, University of Verona, Strada Le Grazie 8, 37134 Verona, Italy
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Marchetti P, Bugliani M, Lupi R, Marselli L, Masini M, Boggi U, Filipponi F, Weir GC, Eizirik DL, Cnop M. The endoplasmic reticulum in pancreatic beta cells of type 2 diabetes patients. Diabetologia 2007; 50:2486-94. [PMID: 17906960 DOI: 10.1007/s00125-007-0816-8] [Citation(s) in RCA: 309] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Accepted: 07/19/2007] [Indexed: 12/23/2022]
Abstract
AIMS/HYPOTHESIS Pancreatic beta cells have highly developed endoplasmic reticulum (ER) due to their role in insulin secretion. Since ER stress has been associated with beta cell dysfunction, we studied several features of beta cell ER in human type 2 diabetes. METHODS Pancreatic samples and/or isolated islets from non-diabetic controls (ND) and type 2 diabetes patients were evaluated for insulin secretion, apoptosis (electron microscopy and ELISA), morphometric ER assessment (electron microscopy), and expression of ER stress markers in beta cell prepared by laser capture microdissection and in isolated islets. RESULTS Insulin release was lower and beta cell apoptosis higher in type 2 diabetes than ND islets. ER density volume was significantly increased in type 2 diabetes beta cells. Expression of alpha-mannosidase (also known as mannosidase, alpha, class 1A, member 1) and UDP-glucose glycoprotein glucosyl transferase like 2 (UGCGL2), assessed by microarray and/or real-time reverse transcriptase polymerase chain reaction (RT-PCR), differed between ND and type 2 diabetes beta cells. Expression of immunoglobulin heavy chain binding protein (BiP, also known as heat shock 70 kDa protein 5 [glucose-regulated protein, 78 kDa] [HSPA5]), X-box binding protein 1 (XBP-1, also known as XBP1) and C/EBP homologous protein (CHOP, also known as damage-inducible transcript 3 [DDIT3]) was not higher in type 2 diabetes beta cell or isolated islets cultured at 5.5 mmol/l glucose (microarray and real-time RT-PCR) than in ND samples. When islets were cultured for 24 h at 11.1 mmol/l glucose, there was induction of BiP and XBP-1 in type 2 diabetes islets but not in ND islets. CONCLUSIONS/INTERPRETATION Beta cell in type 2 diabetes showed modest signs of ER stress when studied in pancreatic samples or isolated islets maintained at physiological glucose concentration. However, exposure to increased glucose levels induced ER stress markers in type 2 diabetes islet cells, which therefore may be more susceptible to ER stress induced by metabolic perturbations.
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Affiliation(s)
- P Marchetti
- Department of Endocrinology and Metabolism, Metabolic Unit, Ospedale Cisanello, University of Pisa, Via Paradisa 2, 56100, Pisa, Italy.
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Brun T, He KHH, Lupi R, Boehm B, Wojtusciszyn A, Sauter N, Donath M, Marchetti P, Maedler K, Gauthier BR. The diabetes-linked transcription factor Pax4 is expressed in human pancreatic islets and is activated by mitogens and GLP-1. Hum Mol Genet 2007; 17:478-89. [DOI: 10.1093/hmg/ddm325] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lyssenko V, Lupi R, Marchetti P, Del Guerra S, Orho-Melander M, Almgren P, Sjögren M, Ling C, Eriksson KF, Lethagen AL, Mancarella R, Berglund G, Tuomi T, Nilsson P, Del Prato S, Groop L. Mechanisms by which common variants in the TCF7L2 gene increase risk of type 2 diabetes. J Clin Invest 2007; 117:2155-63. [PMID: 17671651 PMCID: PMC1934596 DOI: 10.1172/jci30706] [Citation(s) in RCA: 554] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2006] [Accepted: 05/22/2007] [Indexed: 12/11/2022] Open
Abstract
Genetic variants in the gene encoding for transcription factor-7-like 2 (TCF7L2) have been associated with type 2 diabetes (T2D) and impaired beta cell function, but the mechanisms have remained unknown. We therefore studied prospectively the ability of common variants in TCF7L2 to predict future T2D and explored the mechanisms by which they would do this. Scandinavian subjects followed for up to 22 years were genotyped for 3 SNPs (rs7903146, rs12255372, and rs10885406) in TCF7L2, and a subset of them underwent extensive metabolic studies. Expression of TCF7L2 was related to genotype and metabolic parameters in human islets. The CT/TT genotypes of SNP rs7903146 strongly predicted future T2D in 2 independent cohorts (Swedish and Finnish). The risk T allele was associated with impaired insulin secretion, incretin effects, and enhanced rate of hepatic glucose production. TCF7L2 expression in human islets was increased 5-fold in T2D, particularly in carriers of the TT genotype. Overexpression of TCF7L2 in human islets reduced glucose-stimulated insulin secretion. In conclusion, the increased risk of T2D conferred by variants in TCF7L2 involves the enteroinsular axis, enhanced expression of the gene in islets, and impaired insulin secretion.
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Affiliation(s)
- Valeriya Lyssenko
- Department of Clinical Sciences, Diabetes and Endocrinology, and Lund University Diabetes Center, Lund University, Malmö, Sweden.
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48
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Lupi R, Del Guerra S, Mancarella R, Novelli M, Valgimigli L, Pedulli GF, Paolini M, Soleti A, Filipponi F, Mosca F, Boggi U, Del Prato S, Masiello P, Marchetti P. Insulin secretion defects of human type 2 diabetic islets are corrected in vitro by a new reactive oxygen species scavenger. Diabetes Metab 2007; 33:340-5. [PMID: 17616474 DOI: 10.1016/j.diabet.2007.03.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Accepted: 03/25/2007] [Indexed: 01/09/2023]
Abstract
Oxidative stress is a putative mechanism leading to beta-cell damage in type 2 diabetes. We studied isolated human pancreatic islets from type 2 diabetic and non-diabetic subjects, matched for age and body mass index. Evidence of increased oxidative stress in diabetic islets was demonstrated by measuring nitrotyrosine concentration and by electron paramagnetic resonance. This was accompanied by reduced glucose-stimulated insulin secretion, as compared to non-diabetic islets (Stimulation Index, SI: 0.9 +/- 0.2 vs. 2.0 +/- 0.4, P<0.01), and by altered expression of insulin (approximately -60%), catalase (approximately +90%) and glutathione peroxidase (approximately +140%). When type 2 diabetic islets were pre-exposed for 24 h to the new antioxidant bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)decandioate di-hydrochloride, nitrotyrosine levels, glucose-stimulated insulin secretion (SI: 1.6+/-0.5) and gene expressions improved/normalized. These results support the concept that oxidative stress may play a role in type 2 diabetes beta-cell dysfunction; furthermore, it is proposed that therapy with antioxidants could be an interesting adjunctive pharmacological approach to the treatment of type 2 diabetes.
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Affiliation(s)
- R Lupi
- Dipartimento di Endocrinologia e Metabolismo, University of Pisa, Italy
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Del Guerra S, Grupillo M, Masini M, Lupi R, Bugliani M, Torri S, Boggi U, Del Chiaro M, Vistoli F, Mosca F, Del Prato S, Marchetti P. Gliclazide protects human islet beta-cells from apoptosis induced by intermittent high glucose. Diabetes Metab Res Rev 2007; 23:234-8. [PMID: 16952202 DOI: 10.1002/dmrr.680] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Decreased beta-cell mass, mainly due to apoptosis, is crucial for the development and progression of type 2 diabetes. Chronic exposure to high glucose levels is a probable underlying mechanism, whereas the role of oral anti-diabetic agents (sulphonylureas in particular) is still unsettled. METHODS To directly investigate more on such issues, we prepared isolated human islets, which were then cultured for 5 days in continuous normal glucose concentration (NG, 5.5 mmol/L) or normal and high (HG, 16.7 mmol/L) glucose levels (alternating every 24 h), with or without the addition of therapeutical concentration (10 micromol L) of gliclazide or glibenclamide. RESULTS Intermittent high glucose caused a significant decrease of glucose-stimulated insulin secretion, which was not further affected by either sulphonylurea. Apoptosis, as assessed by electron microscopy, was also significantly increased by alternating high glucose exposure, which was accompanied by altered mitochondria morphology and density volume, and increased concentrations of nitrotyrosine, a marker of oxidative stress. Gliclazide, but not glibenclamide, was able to significantly reduce high glucose induced apoptosis, mitochondrial alterations, and nitrotyrosine concentration increase. CONCLUSION Therefore, gliclazide protected human beta-cells from apoptosis induced by intermittent high glucose, and this effect was likely to be due, at least in part, to the anti-oxidant properties of the molecule.
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Affiliation(s)
- S Del Guerra
- Department of Endocrinology and Metabolism, Metabolic Unit, University of Pisa, Pisa, Italy
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Bugliani M, Torri S, Lupi R, Del Guerra S, Grupillo M, Del Chiaro M, Mosca F, Boggi U, Del Prato S, Marchetti P. Effects of C-peptide on isolated human pancreatic islet cells. Diabetes Metab Res Rev 2007; 23:215-9. [PMID: 16874846 DOI: 10.1002/dmrr.674] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Recent data have demonstrated that pro-insulin-derived C-peptide can affect the function of several different cell types. We hypothesized that C-peptide might have an influence on the function and survival of isolated human islets. METHODS Islets were prepared by combining enzymatic digestion and density gradient centrifugation, and the effects of human C-peptide were evaluated acutely and after 24-h incubation. Insulin secretion, apoptosis, quantitative RT-PCR and western-blotting experiments were then performed. RESULTS Glucose-stimulated insulin secretion was not affected by C-peptide and, accordingly, mRNA expression of glucose transporter 2 and glucokinase did not differ between islets pre-cultured or not with the hormone. However, apoptosis was significantly lower in islets exposed to C-peptide than in control islets. This was accompanied by a significant increase of mRNA and protein expression of Bcl2, an anti-apoptotic molecule, with no change in the expression of Bax, a pro-apoptotic molecule. CONCLUSION These results show that in human islets pro-insulin C-peptide has no direct effects on insulin secretion, but it decreases islet cell apoptosis. A direct role of C-peptide on beta-cell mass regulation is therefore suggested.
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Affiliation(s)
- Marco Bugliani
- Department of Endocrinology and Metabolism - Metabolic Unit, University of Pisa, Pisa, Italy
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