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Nagao M, Asai A, Eliasson L, Oikawa S. Selectively bred rodent models for studying the etiology of type 2 diabetes: Goto-Kakizaki rats and Oikawa-Nagao mice. Endocr J 2023; 70:19-30. [PMID: 36477370 DOI: 10.1507/endocrj.ej22-0253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Type 2 diabetes (T2D) is a polygenic disease and studies to understand the etiology of the disease have required selectively bred animal models with polygenic background. In this review, we present two models; the Goto-Kakizaki (GK) rat and the Oikawa-Nagao Diabetes-Prone (ON-DP) and Diabetes-Resistant (ON-DR) mouse. The GK rat was developed by continuous selective breeding for glucose tolerance from the outbred Wistar rat around 50 years ago. The main cause of spontaneous hyperglycemia in this model is insulin secretion deficiency from pancreatic β-cells and mild insulin resistance in insulin target organs. A disadvantage of the GK rat is that environmental factors have not been considered in the selective breeding. Hence, the GK rat may not be suitable for elucidating predisposition to diabetes under certain environmental conditions, such as a high-fat diet. Therefore, we recently established two mouse lines with different susceptibilities to diet-induced diabetes, which are prone and resistant to the development of diabetes, designated as the ON-DP and ON-DR mouse, respectively. The two ON mouse lines were established by continuous selective breeding for inferior and superior glucose tolerance after high-fat diet feeding in hybrid mice of three inbred strains. Studies of phenotypic differences between ON-DP and ON-DR mice and their underlying molecular mechanisms will shed light on predisposing factors for the development of T2D in the modern obesogenic environment. This review summarizes the background and the phenotypic differences and similarities of GK rats and ON mice and highlights the advantages of using selectively bred rodent models in diabetes research.
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Affiliation(s)
- Mototsugu Nagao
- Department of Endocrinology, Metabolism and Nephrology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8603, Japan
- Islet Cell Exocytosis, Lund University Diabetes Centre, Department of Clinical Sciences Malmö, Lund University, Malmö 214 28, Sweden
- Clincal Research Centre (CRC), Skåne University Hospital(SUS), Malmö 214 28, Sweden
| | - Akira Asai
- Department of Endocrinology, Metabolism and Nephrology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8603, Japan
| | - Lena Eliasson
- Islet Cell Exocytosis, Lund University Diabetes Centre, Department of Clinical Sciences Malmö, Lund University, Malmö 214 28, Sweden
- Clincal Research Centre (CRC), Skåne University Hospital(SUS), Malmö 214 28, Sweden
| | - Shinichi Oikawa
- Department of Endocrinology, Metabolism and Nephrology, Graduate School of Medicine, Nippon Medical School, Tokyo 113-8603, Japan
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2
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Kilanowska A, Szkudelski T. Effects of inhibition of phosphodiesterase 3B in pancreatic islets on insulin secretion: a potential link with some stimulatory pathways. Arch Physiol Biochem 2021; 127:250-257. [PMID: 31240952 DOI: 10.1080/13813455.2019.1628071] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Elevated intracellular cAMP concentrations potentiate insulin secretion from pancreatic β cells. Phosphodiesterase 3B (PDE3B) is highly expressed in these cells and plays a role in the regulation of insulin secretion. MATERIALS AND METHODS In this study, effects of amrinone, an inhibitor of PDE3B on insulin release from isolated pancreatic islets, were determined. RESULTS Exposure of islets to amrinone for 15, 30 and 90 min markedly increased secretion induced by 6.7 mM glucose. Amrinone enhanced also secretion stimulated by 6.7 mM glucose and DB-cAMP, an activator of PKA. It was also demonstrated that amrinone potentiated insulin secretion induced by 6.7 mM glucose in the combination with PMA (activator of PKC) or acetylcholine. However, the insulin-secretory response to glucose and glibenclamide was unchanged by amrinone. CONCLUSIONS These results indicate that amrinone is capable of increasing insulin secretion; however, its action is restricted.
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Affiliation(s)
- Agnieszka Kilanowska
- Department of Anatomy and Histology, University of Zielona Gora, Zielona Gora, Poland
| | - Tomasz Szkudelski
- Department of Animal Physiology and Biochemistry, Poznan University of Life Sciences, Poznan, Poland
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Nagao M, Esguerra JLS, Wendt A, Asai A, Sugihara H, Oikawa S, Eliasson L. Selectively Bred Diabetes Models: GK Rats, NSY Mice, and ON Mice. Methods Mol Biol 2020; 2128:25-54. [PMID: 32180184 DOI: 10.1007/978-1-0716-0385-7_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The polygenic background of selectively bred diabetes models mimics the etiology of type 2 diabetes. So far, three different rodent models (Goto-Kakizaki rats, Nagoya-Shibata-Yasuda mice, and Oikawa-Nagao mice) have been established in the diabetes research field by continuous selective breeding for glucose tolerance from outbred rodent stocks. The origin of hyperglycemia in these rodents is mainly insulin secretion deficiency from the pancreatic β-cells and mild insulin resistance in insulin target organs. In this chapter, we summarize backgrounds and phenotypes of these rodent models to highlight their importance in diabetes research. Then, we introduce experimental methodologies to evaluate β-cell exocytosis as a putative common defect observed in these rodent models.
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MESH Headings
- Animals
- Diabetes Mellitus, Experimental/etiology
- Diabetes Mellitus, Experimental/genetics
- Diabetes Mellitus, Experimental/metabolism
- Diabetes Mellitus, Type 1/etiology
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/metabolism
- Diabetes Mellitus, Type 2/etiology
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/metabolism
- Exocytosis
- Gene Expression Profiling/methods
- Glucose Intolerance
- Insulin Resistance/physiology
- Insulin Secretion/physiology
- Insulin-Secreting Cells/chemistry
- Insulin-Secreting Cells/cytology
- Insulin-Secreting Cells/metabolism
- Insulin-Secreting Cells/physiology
- Mice
- Mice, Inbred C3H
- Patch-Clamp Techniques/methods
- Phenotype
- Rats
- Rats, Wistar
- Selective Breeding/genetics
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Affiliation(s)
- Mototsugu Nagao
- Islet Cell Exocytosis, Lund University Diabetes Centre, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden.
- Clinical Research Centre, Skåne University Hospital, Lund and Malmö, Sweden.
- Department of Endocrinology, Diabetes and Metabolism, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.
| | - Jonathan Lou S Esguerra
- Islet Cell Exocytosis, Lund University Diabetes Centre, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Clinical Research Centre, Skåne University Hospital, Lund and Malmö, Sweden
| | - Anna Wendt
- Islet Cell Exocytosis, Lund University Diabetes Centre, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
- Clinical Research Centre, Skåne University Hospital, Lund and Malmö, Sweden
| | - Akira Asai
- Department of Endocrinology, Diabetes and Metabolism, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
- Food and Health Science Research Unit, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Hitoshi Sugihara
- Department of Endocrinology, Diabetes and Metabolism, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Shinichi Oikawa
- Department of Endocrinology, Diabetes and Metabolism, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
- Diabetes and Lifestyle-related Disease Center, Japan Anti-Tuberculosis Association, Fukujuji Hospital, Tokyo, Japan
| | - Lena Eliasson
- Islet Cell Exocytosis, Lund University Diabetes Centre, Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden.
- Clinical Research Centre, Skåne University Hospital, Lund and Malmö, Sweden.
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Gandasi NR, Yin P, Riz M, Chibalina MV, Cortese G, Lund PE, Matveev V, Rorsman P, Sherman A, Pedersen MG, Barg S. Ca2+ channel clustering with insulin-containing granules is disturbed in type 2 diabetes. J Clin Invest 2017; 127:2353-2364. [PMID: 28481223 PMCID: PMC5451232 DOI: 10.1172/jci88491] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Accepted: 03/16/2017] [Indexed: 01/27/2023] Open
Abstract
Loss of first-phase insulin secretion is an early sign of developing type 2 diabetes (T2D). Ca2+ entry through voltage-gated L-type Ca2+ channels triggers exocytosis of insulin-containing granules in pancreatic β cells and is required for the postprandial spike in insulin secretion. Using high-resolution microscopy, we have identified a subset of docked insulin granules in human β cells and rat-derived clonal insulin 1 (INS1) cells for which localized Ca2+ influx triggers exocytosis with high probability and minimal latency. This immediately releasable pool (IRP) of granules, identified both structurally and functionally, was absent in β cells from human T2D donors and in INS1 cells cultured in fatty acids that mimic the diabetic state. Upon arrival at the plasma membrane, IRP granules slowly associated with 15 to 20 L-type channels. We determined that recruitment depended on a direct interaction with the synaptic protein Munc13, because expression of the II–III loop of the channel, the C2 domain of Munc13-1, or of Munc13-1 with a mutated C2 domain all disrupted L-type channel clustering at granules and ablated fast exocytosis. Thus, rapid insulin secretion requires Munc13-mediated recruitment of L-type Ca2+ channels in close proximity to insulin granules. Loss of this organization underlies disturbed insulin secretion kinetics in T2D.
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Affiliation(s)
| | - Peng Yin
- Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Michela Riz
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Margarita V Chibalina
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, United Kingdom
| | - Giuliana Cortese
- Department of Statistical Sciences, University of Padova, Padova, Italy
| | - Per-Eric Lund
- Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Victor Matveev
- Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, New Jersey, USA
| | - Patrik Rorsman
- Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, United Kingdom
| | - Arthur Sherman
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA
| | - Morten G Pedersen
- Department of Information Engineering, University of Padova, Padova, Italy
| | - Sebastian Barg
- Medical Cell Biology, Uppsala University, Uppsala, Sweden
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Balbo SL, Ribeiro RA, Mendes MC, Lubaczeuski C, Maller ACPA, Carneiro EM, Bonfleur ML. Vagotomy diminishes obesity in cafeteria rats by decreasing cholinergic potentiation of insulin release. J Physiol Biochem 2016; 72:625-633. [PMID: 27351887 DOI: 10.1007/s13105-016-0501-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 06/21/2016] [Indexed: 01/06/2023]
Abstract
Herein, we investigated whether subdiaphragmatic vagotomy has benefits on obesity, body glucose homeostasis, and insulin secretion in cafeteria (CAF)-obese rats. Wistar rats were fed a standard or CAF diet for 12 weeks. Subsequently, CAF rats were randomly submitted to truncal vagotomy (CAF Vag) or sham operation (CAF Sham). CAF Sham rats were hyperphagic, obese, and presented metabolic disturbances, including hyperinsulinemia, glucose intolerance, insulin resistance, hyperglycemia, and hypertriglyceridemia. Twelve weeks after vagotomy, CAF Vag rats presented reductions in body weight and perigonadal fat stores. Vagotomy did not modify glucose tolerance but normalized fed glycemia, insulinemia, and insulin sensitivity. Isolated islets from CAF Sham rats secreted more insulin in response to the cholinergic agent, carbachol, and when intracellular cyclic adenine monophosphate (cAMP) is enhanced by forskolin or 3-isobutyl-1-methylxanthine. Vagotomy decreased glucose-induced insulin release due to a reduction in the cholinergic action on β-cells. This effect also normalized islet secretion in response to cAMP. Therefore, vagotomy in rats fed on a CAF-style diet effectively decreases adiposity and restores insulin sensitivity. These effects were mainly associated with the lack of cholinergic action on the endocrine pancreas, which decreases insulinemia and may gradually reduce fat storage and improve insulin sensitivity.
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Affiliation(s)
- Sandra Lucinei Balbo
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, UNIOESTE, Cascavel, PR, 858119-110, Brazil
| | | | - Mariana Carla Mendes
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, UNIOESTE, Cascavel, PR, 858119-110, Brazil
| | - Camila Lubaczeuski
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, UNIOESTE, Cascavel, PR, 858119-110, Brazil
| | - Ana Claudia Paiva Alegre Maller
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, UNIOESTE, Cascavel, PR, 858119-110, Brazil
| | - Everardo Magalhães Carneiro
- Laboratório de Pâncreas Endócrino e Metabolismo, Departamento de Biologia Estrutural e Funcional, Instituto de Biologia, UNICAMP, Campinas, SP, Brazil
| | - Maria Lúcia Bonfleur
- Laboratório de Fisiologia Endócrina e Metabolismo, Centro de Ciências Biológicas e da Saúde, UNIOESTE, Cascavel, PR, 858119-110, Brazil.
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Pancreatic Beta Cell G-Protein Coupled Receptors and Second Messenger Interactions: A Systems Biology Computational Analysis. PLoS One 2016; 11:e0152869. [PMID: 27138453 PMCID: PMC4854486 DOI: 10.1371/journal.pone.0152869] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 03/21/2016] [Indexed: 12/17/2022] Open
Abstract
Insulin secretory in pancreatic beta-cells responses to nutrient stimuli and hormonal modulators include multiple messengers and signaling pathways with complex interdependencies. Here we present a computational model that incorporates recent data on glucose metabolism, plasma membrane potential, G-protein-coupled-receptors (GPCR), cytoplasmic and endoplasmic reticulum calcium dynamics, cAMP and phospholipase C pathways that regulate interactions between second messengers in pancreatic beta-cells. The values of key model parameters were inferred from published experimental data. The model gives a reasonable fit to important aspects of experimentally measured metabolic and second messenger concentrations and provides a framework for analyzing the role of metabolic, hormones and neurotransmitters changes on insulin secretion. Our analysis of the dynamic data provides support for the hypothesis that activation of Ca2+-dependent adenylyl cyclases play a critical role in modulating the effects of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and catecholamines. The regulatory properties of adenylyl cyclase isoforms determine fluctuations in cytoplasmic cAMP concentration and reveal a synergistic action of glucose, GLP-1 and GIP on insulin secretion. On the other hand, the regulatory properties of phospholipase C isoforms determine the interaction of glucose, acetylcholine and free fatty acids (FFA) (that act through the FFA receptors) on insulin secretion. We found that a combination of GPCR agonists activating different messenger pathways can stimulate insulin secretion more effectively than a combination of GPCR agonists for a single pathway. This analysis also suggests that the activators of GLP-1, GIP and FFA receptors may have a relatively low risk of hypoglycemia in fasting conditions whereas an activator of muscarinic receptors can increase this risk. This computational analysis demonstrates that study of second messenger pathway interactions will improve understanding of critical regulatory sites, how different GPCRs interact and pharmacological targets for modulating insulin secretion in type 2 diabetes.
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7
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Taurine supplementation regulates pancreatic islet function in response to potentiating agents in leptin-deficient obese mice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 803:371-85. [PMID: 25833510 DOI: 10.1007/978-3-319-15126-7_28] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Impaired muscarinic type 3 (M3) receptor/PKC and PKA pathways in islets from MSG-obese rats. Mol Biol Rep 2013; 40:4521-8. [DOI: 10.1007/s11033-013-2546-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 04/29/2013] [Indexed: 10/26/2022]
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Portha B, Giroix MH, Tourrel-Cuzin C, Le-Stunff H, Movassat J. The GK rat: a prototype for the study of non-overweight type 2 diabetes. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2012; 933:125-59. [PMID: 22893405 DOI: 10.1007/978-1-62703-068-7_9] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Type 2 diabetes mellitus (T2D) arises when the endocrine pancreas fails to secrete sufficient insulin to cope with the metabolic demand because of β-cell secretory dysfunction and/or decreased β-cell mass. Defining the nature of the pancreatic islet defects present in T2D has been difficult, in part because human islets are inaccessible for direct study. This review is aimed to illustrate to what extent the Goto Kakizaki rat, one of the best characterized animal models of spontaneous T2D, has proved to be a valuable tool offering sufficient commonalities to study this aspect. A comprehensive compendium of the multiple functional GK abnormalities so far identified is proposed in this perspective, together with their time-course and interactions. A special focus is given toward the pathogenesis of defective β-cell number and function in the GK model. It is proposed that the development of T2D in the GK model results from the complex interaction of multiple events: (1) several susceptibility loci containing genes responsible for some diabetic traits; (2) gestational metabolic impairment inducing an epigenetic programming of the offspring pancreas and the major insulin target tissues; and (3) environmentally induced loss of β-cell differentiation due to chronic exposure to hyperglycemia/hyperlipidemia, inflammation, and oxidative stress.
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Affiliation(s)
- Bernard Portha
- Laboratoire B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptive), Université Paris-Diderot, CNRS EAC 4413, Paris, France.
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Dolz M, Movassat J, Bailbé D, Le Stunff H, Giroix MH, Fradet M, Kergoat M, Portha B. cAMP-secretion coupling is impaired in diabetic GK/Par rat β-cells: a defect counteracted by GLP-1. Am J Physiol Endocrinol Metab 2011; 301:E797-806. [PMID: 21750265 DOI: 10.1152/ajpendo.00652.2010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
cAMP-raising agents with glucagon-like peptide-1 (GLP-1) as the first in class, exhibit multiple actions that are beneficial for the treatment of type 2 diabetic (T2D) patients, including improvement of glucose-induced insulin secretion (GIIS). To gain additional insight into the role of cAMP in the disturbed stimulus-secretion coupling within the diabetic β-cell, we examined more thoroughly the relationship between changes in islet cAMP concentration and insulin release in the GK/Par rat model of T2D. Basal cAMP content in GK/Par islets was significantly higher, whereas their basal insulin release was not significantly different from that of Wistar (W) islets. Even in the presence of IBMX or GLP-1, their insulin release did not significantly change despite further enhanced cAMP accumulation in both cases. The high basal cAMP level most likely reflects an increased cAMP generation in GK/Par compared with W islets since 1) forskolin dose-dependently induced an exaggerated cAMP accumulation; 2) adenylyl cyclase (AC)2, AC3, and G(s)α proteins were overexpressed; 3) IBMX-activated cAMP accumulation was less efficient and PDE-3B and PDE-1C mRNA were decreased. Moreover, the GK/Par insulin release apparatus appears less sensitive to cAMP, since GK/Par islets released less insulin at submaximal cAMP levels and required five times more cAMP to reach a maximal secretion rate no longer different from W. GLP-1 was able to reactivate GK/Par insulin secretion so that GIIS became indistinguishable from that of W. The exaggerated cAMP production is instrumental, since GLP-1-induced GIIS reactivation was lost in the presence the AC blocker 2',5'-dideoxyadenosine. This GLP-1 effect takes place in the absence of any improvement of the [Ca(2+)](i) response and correlates with activation of the cAMP-dependent PKA-dependent pathway.
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Affiliation(s)
- Manuel Dolz
- Université Paris-Diderot, Sorbonne-Paris-Cité, Laboratoire B2PE (Biologie et Pathologie du Pancreas Endocrine), Unité Biologie Fonctionnelle et Adaptive, EAC 4413, Centre National de Recherche Scientifique, Paris, France
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Ceramide synthase 4 and de novo production of ceramides with specific N-acyl chain lengths are involved in glucolipotoxicity-induced apoptosis of INS-1 β-cells. Biochem J 2011; 438:177-89. [PMID: 21592087 DOI: 10.1042/bj20101386] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Pancreatic β-cell apoptosis induced by palmitate requires high glucose concentrations. Ceramides have been suggested to be important mediators of glucolipotoxicity-induced β-cell apoptosis. In INS-1 β-cells, 0.4 mM palmitate with 5 mM glucose increased the levels of dihydrosphingosine and dihydroceramides, two lipid intermediates in the de novo biosynthesis of ceramides, without inducing apoptosis. Increasing glucose concentrations to 30 mM amplified palmitate-induced accumulation of dihydrosphingosine and the formation of (dihydro)ceramides. Of note, glucolipotoxicity specifically induced the formation of C(18:0), C(22:0) and C(24:1) (dihydro)ceramide molecular species, which was associated with the up-regulation of CerS4 (ceramide synthase 4) levels. Fumonisin-B1, a ceramide synthase inhibitor, partially blocked apoptosis induced by glucolipotoxicity. In contrast, apoptosis was potentiated in the presence of D,L-threo-1-phenyl-2-palmitoylamino-3-morpholinopropan-1-ol, an inhibitor of glucosylceramide synthase. Moreover, overexpression of CerS4 amplified ceramide production and apoptosis induced by palmitate with 30 mM glucose, whereas down-regulation of CerS4 by siRNA (short interfering RNA) reduced apoptosis. CerS4 also potentiates ceramide accumulation and apoptosis induced by another saturated fatty acid: stearate. Collectively, our results suggest that glucolipotoxicity induces β-cell apoptosis through a dual mechanism involving de novo ceramide biosynthesis and the formation of ceramides with specific N-acyl chain lengths rather than an overall increase in ceramide content.
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Ndong M, Uehara M, Katsumata SI, Suzuki K. Effects of Oral Administration of Moringa oleifera Lam on Glucose Tolerance in Goto-Kakizaki and Wistar Rats. J Clin Biochem Nutr 2011; 40:229-33. [PMID: 18398501 PMCID: PMC2275769 DOI: 10.3164/jcbn.40.229] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2006] [Accepted: 12/27/2006] [Indexed: 11/22/2022] Open
Abstract
Medicinal plants constitute an important source of potential therapeutic agents for diabetes. In the present study, we investigated the effects of Moringa oleifera (MO) Lam, Moringacea, on glucose tolerance in Wistar rats and Goto-Kakizaki (GK) rats, modeled type 2 diabetes. Major polyphenols in MO powder were quercetin glucosides, rutin, kaempferol glycosides and chlorogenic acids by HPLC analysis. As the results of glucose tolerance test, MO significantly decreased the blood glucose at 20, 30, 45and 60 min for GK rats and at 10, 30 and 45 min for Wistar rats (p<0.05) compared to the both controls after glucose administration. The area under the curve of changes in the blood glucose was significantly higher in the GK control group than in the GK plus MO group (p<0.05) in the periods 30–60 min and 60–120 min. Furthermore, MO significantly decreased stomach emptying in GK rats (p<0.05). The results indicated that MO has an ameliorating effect for glucose intolerance, and the effect might be mediated by quercetin-3-glucoside and fiber contents in MO leaf powder. The action of MO was greater in GK rats than in Wistar rats.
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Affiliation(s)
- Moussa Ndong
- Department of Nutritional Science, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502, Japan
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Cyclic AMP signaling in pancreatic islets. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 654:281-304. [PMID: 20217503 DOI: 10.1007/978-90-481-3271-3_13] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cyclic 3'5'AMP (cAMP) is an important physiological amplifier of glucose-induced insulin secretion by the pancreatic islet beta-cell, where it is formed by the activity of adenylyl cyclases, which are stimulated by glucose, through elevation in intracellular calcium concentrations, and by the incretin hormones (GLP-1 and GIP). cAMP is rapidly degraded in the pancreatic islet beta-cell by various cyclic nucleotide phosphodiesterase (PDE) enzymes. Many steps involved in glucose-induced insulin secretion are modulated by cAMP, which is also important in regulating pancreatic islet beta-cell differentiation, growth and survival. This chapter discusses the formation, destruction and actions of cAMP in the islets with particular emphasis on the beta-cell.
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14
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Lacraz G, Figeac F, Movassat J, Kassis N, Portha B. Diabetic GK/Par rat beta-cells are spontaneously protected against H2O2-triggered apoptosis. A cAMP-dependent adaptive response. Am J Physiol Endocrinol Metab 2010; 298:E17-27. [PMID: 19843875 DOI: 10.1152/ajpendo.90871.2008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The alteration of the beta-cell population in the Goto-Kakizaki rat (GK/Par line), a model of spontaneous type 2 diabetes, has been ascribed to significantly decreased beta-cell replication and neogenesis, while beta-cell apoptosis is surprisingly not enhanced and remains in the normal range. To gain insight into the mechanisms by which those beta-cells are protected from death, we studied ex vivo the apoptotic activity and the expression of a large set of pro/antiapoptotic and pro/antioxidant genes in GK/Par islet cells. This was done in vitro in freshly isolated islets as well as in response to culture conditions and calibrated reactive oxygen species (ROS) exposure (i.e., H2O2). We also investigated the intracellular mechanisms of the diabetic beta-cell response to ROS, the role if any of the intracellular cAMP metabolism, and finally the kinetic of ROS response, taking advantage of the GK/Par rat normoglycemia until weaning. Our results show that the peculiar GK/Par beta-cell phenotype was correlated with an increased expression of a large panel of antioxidant genes as well as pro/antiapoptotic genes. We demonstrate that such combination confers resistance to cytotoxic H2O2 exposure in vitro, raising the possibility that at least some of the activated stress/defense genes have protective effects against H2O2-triggered beta-cell death. We also present some evidence that the GK/Par beta-cell resistance to H2O2 is at least partly cAMP dependent. Finally, we show that such a phenotype is not innate but is spontaneously acquired after diabetes onset as the result of an adaptive response to the diabetic environment.
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MESH Headings
- Adaptation, Physiological/physiology
- Animals
- Apoptosis/drug effects
- Apoptosis/physiology
- Apoptosis Regulatory Proteins/genetics
- Apoptosis Regulatory Proteins/metabolism
- Cell Division/physiology
- Cells, Cultured
- Cyclic AMP/metabolism
- Cyclin D1/genetics
- Cyclin D1/metabolism
- Diabetes Mellitus, Type 2/metabolism
- Diabetes Mellitus, Type 2/pathology
- Disease Models, Animal
- Heme Oxygenase-1/genetics
- Heme Oxygenase-1/metabolism
- Hydrogen Peroxide/pharmacology
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Insulin-Secreting Cells/metabolism
- Insulin-Secreting Cells/pathology
- Male
- Oxidants/pharmacology
- Proto-Oncogene Proteins c-myc/genetics
- Proto-Oncogene Proteins c-myc/metabolism
- RNA, Messenger/metabolism
- Rats
- Rats, Mutant Strains
- Rats, Wistar
- Reactive Oxygen Species/metabolism
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Affiliation(s)
- Grégory Lacraz
- Laboratoire Biologie et Pathologie du Pancréas Endocrine, Unité Biologie Fonctionnelle et Adaptive, Equipe 1, Université Paris-Diderot et CNRS EAC-4413, Paris, France
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15
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Portha B, Lacraz G, Chavey A, Figeac F, Fradet M, Tourrel-Cuzin C, Homo-Delarche F, Giroix MH, Bailbé D, Gangnerau MN, Movassat J. Islet structure and function in the GK rat. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 654:479-500. [PMID: 20217511 DOI: 10.1007/978-90-481-3271-3_21] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Type 2 diabetes mellitus (T2D) arises when the endocrine pancreas fails to secrete sufficient insulin to cope with the metabolic demand because of beta-cell secretory dysfunction and/or decreased beta-cell mass. Defining the nature of the pancreatic islet defects present in T2D has been difficult, in part because human islets are inaccessible for direct study. This review is aimed to illustrate to what extent the Goto-Kakizaki rat, one of the best characterized animal models of spontaneous T2D, has proved to be a valuable tool offering sufficient commonalities to study this aspect. A comprehensive compendium of the multiple functional GK islet abnormalities so far identified is proposed in this perspective. The pathogenesis of defective beta-cell number and function in the GK model is also discussed. It is proposed that the development of T2D in the GK model results from the complex interaction of multiple events: (i) several susceptibility loci containing genes responsible for some diabetic traits (distinct loci encoding impairment of beta-cell metabolism and insulin exocytosis, but no quantitative trait locus for decreased beta-cell mass); (ii) gestational metabolic impairment inducing an epigenetic programming of the offspring pancreas (decreased beta-cell neogenesis and proliferation) transmitted over generations; and (iii) loss of beta-cell differentiation related to chronic exposure to hyperglycaemia/hyperlipidaemia, islet inflammation, islet oxidative stress, islet fibrosis and perturbed islet vasculature.
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Affiliation(s)
- Bernard Portha
- Laboratoire B2PE, Unité BFA, Université Paris-Diderot et CNRS EAC4413, F - 75205 Paris Cedex13, France.
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16
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Lacraz G, Figeac F, Movassat J, Kassis N, Coulaud J, Galinier A, Leloup C, Bailbé D, Homo-Delarche F, Portha B. Diabetic beta-cells can achieve self-protection against oxidative stress through an adaptive up-regulation of their antioxidant defenses. PLoS One 2009; 4:e6500. [PMID: 19654863 PMCID: PMC2715861 DOI: 10.1371/journal.pone.0006500] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Accepted: 07/03/2009] [Indexed: 01/13/2023] Open
Abstract
Background Oxidative stress (OS), through excessive and/or chronic reactive oxygen species (ROS), is a mediator of diabetes-related damages in various tissues including pancreatic β-cells. Here, we have evaluated islet OS status and β-cell response to ROS using the GK/Par rat as a model of type 2 diabetes. Methodology/Principal Findings Localization of OS markers was performed on whole pancreases. Using islets isolated from 7-day-old or 2.5-month-old male GK/Par and Wistar control rats, 1) gene expression was analyzed by qRT-PCR; 2) insulin secretion rate was measured; 3) ROS accumulation and mitochondrial polarization were assessed by fluorescence methods; 4) antioxidant contents were quantified by HPLC. After diabetes onset, OS markers targeted mostly peri-islet vascular and inflammatory areas, and not islet cells. GK/Par islets revealed in fact protected against OS, because they maintained basal ROS accumulation similar or even lower than Wistar islets. Remarkably, GK/Par insulin secretion also exhibited strong resistance to the toxic effect of exogenous H2O2 or endogenous ROS exposure. Such adaptation was associated to both high glutathione content and overexpression (mRNA and/or protein levels) of a large set of genes encoding antioxidant proteins as well as UCP2. Finally, we showed that such a phenotype was not innate but spontaneously acquired after diabetes onset, as the result of an adaptive response to the diabetic environment. Conclusions The GK/Par model illustrates the effectiveness of adaptive response to OS by β-cells to achieve self-tolerance. It remains to be determined to what extend such islet antioxidant defenses upregulation might contribute to GK/Par β-cell secretory dysfunction.
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Affiliation(s)
- Grégory Lacraz
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Florence Figeac
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Jamileh Movassat
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Nadim Kassis
- Equipe HERGE, Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Josiane Coulaud
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Anne Galinier
- UMR 5241, CNRS and Université P. Sabatier, CHU Rangueil, Toulouse, France
| | - Corinne Leloup
- UMR 5241, CNRS and Université P. Sabatier, CHU Rangueil, Toulouse, France
| | - Danielle Bailbé
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Françoise Homo-Delarche
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
| | - Bernard Portha
- Equipe B2PE (Biologie et Pathologie du Pancréas Endocrine), Unité BFA (Biologie Fonctionnelle et Adaptative), Université Paris-Diderot et CNRS EAC7059, Paris, France
- * E-mail:
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17
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Mizukami H, Wada R, Koyama M, Takeo T, Suga S, Wakui M, Yagihashi S. Augmented beta cell loss and mitochondrial abnormalities in sucrose-fed GK rats. Virchows Arch 2008; 452:383-92. [PMID: 18236074 DOI: 10.1007/s00428-007-0508-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 08/22/2007] [Accepted: 09/02/2007] [Indexed: 11/27/2022]
Abstract
Progressive decline of islet beta cell mass is a hallmark of type 2 diabetes, where nutritional insults are invoked in the pathologic process. Its detailed mechanisms are, however, incompletely understood. We explored the effect of sucrose diet on mitochondria in Goto Kakizaki (GK) rats, a spontaneously diabetic model. Six-week-old male GK rats were given 30% sucrose orally for 2 weeks. Normal Wistar rats fed with sucrose served as controls. Compared to untreated GK rats, sucrose-fed GK rats showed severe degeneration and death of beta cells with disrupted and swollen mitochondria and a greater beta cell loss. Submicroscopic analysis disclosed a smaller mean volume and a greater number of mitochondria in beta cells in GK rats compared to those in Wistar rats. Mitochondria in sucrose-fed GK rats were 2.4-fold greater in mean volume than those in untreated state. Without sucrose feeding, there was no significant difference in mitochondrial membrane potentials (MmPs) of isolated islets between Wistar and GK rats. MmPs were reduced by 44% in sucrose-fed GK rats but not influenced in sucrose-fed Wistar rats. Current results suggest that nutritional insults like sucrose feeding may exert deleterious effects on mitochondria, resulting in augmented beta cell loss in type 2 diabetes.
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Affiliation(s)
- Hiroki Mizukami
- Department of Pathology and Molecular Medicine, Hirosaki University Graduate School of Medicine, 5 Zaifu-cho, Hirosaki 036-8562, Japan
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18
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Portha B, Lacraz G, Dolz M, Homo-Delarche F, Giroix MH, Movassat J. Defective functional β-cell mass and Type 2 diabetes in the Goto-Kakizaki rat model. Expert Rev Endocrinol Metab 2007; 2:785-795. [PMID: 30290473 DOI: 10.1586/17446651.2.6.785] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Increasing evidence indicates that decreased functional β-cell mass is the hallmark of Type 2 diabetes mellitus. Therefore, the debate focuses on the possible mechanisms responsible for abnormal islet microenvironment, decreased β-cell number, impaired β-cell function and their multifactorial etiologies. The information available on the Goto-Kakizaki/Par rat line, one of the best characterized animal models of spontaneous Type 2 diabetes mellitus, are reviewed in such a perspective. We propose that the defective β-cell mass and function in the Goto-Kakizaki/Par model reflect the complex interactions of multiple pathogenic players, including several independent loci containing genes responsible for some diabetic traits (but not decreased β-cell mass), gestational metabolic impairment inducing an epigenetic programming of the pancreas (decreased β-cell neogenesis), which is transmitted to the next generation, and loss of β-cell differentiation due to chronic exposure to hyperglycemia, inflammatory mediators, oxidative stress and perturbed islet microarchitecture.
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Affiliation(s)
- Bernard Portha
- a Professor, Laboratoire de Physiopathologie de la Nutrition, CNRS UMR 7059, Université Paris-Diderot, 2 Place Jussieu, 75251 Paris Cedex 05, France.
| | - G Lacraz
- b Groupe Biologie et Pathologie du Pancréas Endocrine, Laboratoire de Physiopathologie de la Nutrition, UMR CNRS 7059, Université Paris-Diderot, UP7, Paris, France
| | - M Dolz
- b Groupe Biologie et Pathologie du Pancréas Endocrine, Laboratoire de Physiopathologie de la Nutrition, UMR CNRS 7059, Université Paris-Diderot, UP7, Paris, France
| | - F Homo-Delarche
- c Chargé de Recherche, Groupe Biologie et Pathologie du Pancréas Endocrine, Laboratoire de Physiopathologie de la Nutrition, UMR CNRS 7059, Université Paris-Diderot, UP7, Paris, France
| | - M-H Giroix
- b Groupe Biologie et Pathologie du Pancréas Endocrine, Laboratoire de Physiopathologie de la Nutrition, UMR CNRS 7059, Université Paris-Diderot, UP7, Paris, France
| | - J Movassat
- d Assistant Professor, Groupe Biologie et Pathologie du Pancréas Endocrine, Laboratoire de Physiopathologie de la Nutrition, UMR CNRS 7059, Université Paris-Diderot, UP7, Paris, France
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19
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Ostenson CG, Efendic S. Islet gene expression and function in type 2 diabetes; studies in the Goto-Kakizaki rat and humans. Diabetes Obes Metab 2007; 9 Suppl 2:180-6. [PMID: 17919192 DOI: 10.1111/j.1463-1326.2007.00787.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Defective beta-cell function with resulting impairment of glucose-stimulated insulin release is a critical factor in the pathogenesis of type 2 diabetes. Accumulated studies in pancreatic islets of the spontaneously diabetic Goto-Kakizaki (GK) rat suggest that this is a useful animal model of type 2 diabetes. The GK rat is non-obese, and abnormal glucose regulation develops early in life in association with impaired insulin secretion. There are some differences in islet morphology and function reported between different GK rat colonies. In addition to reduction of beta-cell mass, a number of beta-cell defects have been described with possible relevance for the reduced insulin secretion. Interestingly, some of these defects have also been shown in isolated islets from type 2 diabetic humans. The polygenic nature of diabetes heredity in the GK rat may well resemble the genetic basis in the majority of patients with type 2 diabetes. Here, we review studies concerning beta-cell function and islet gene expression in the GK rat and compare it with the limited number of investigations on similar topics in isolated islets from patients with type 2 diabetes.
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Affiliation(s)
- C-G Ostenson
- Department of Molecular Medicine and Surgery, Endocrine and Diabetes Unit, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
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20
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Nunes E, Peixoto F, Louro T, Sena CM, Santos MS, Matafome P, Moreira PI, Seiça R. Soybean oil treatment impairs glucose-stimulated insulin secretion and changes fatty acid composition of normal and diabetic islets. Acta Diabetol 2007; 44:121-30. [PMID: 17721750 DOI: 10.1007/s00592-007-0252-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2006] [Accepted: 03/19/2007] [Indexed: 10/22/2022]
Abstract
We investigated the effect of sub-chronic soybean oil (SO) treatment on the insulin secretion and fatty acid composition of islets of Langerhans obtained from Goto-Kakizaki (GK), a model of type 2 diabetes, and normal Wistar rats. We observed that soybean-treated Wistar rats present insulin resistance and defective islet insulin secretion when compared with untreated Wistar rats. The decrease in insulin secretion occurred at all concentrations of glucose and arginine tested. Furthermore we observed that soybean-treated normal islets present a significant decrease in two saturated fatty acids, myristic and heneicosanoic acids, and one monounsaturated eicosenoic acid, and the appearance of the monounsaturated erucic acid. Concerning diabetic animals, we observed that soybean-treated diabetic rats, when compared with untreated GK rats, present an increase in plasma non-fasting free fatty acids, an exacerbation of islet insulin secretion impairment in all conditions tested and a significant decrease in the monounsaturated palmitoleic acid. Altogether our results show that SO treatment results in a decrease of insulin secretion and alterations on fatty acid composition in normal and diabetic islets. Furthermore, the impairment of insulin secretion, islet erucic acid and fasting plasma insulin levels are similar in treated normal and untreated diabetic rats, suggesting that SO could have a deleterious effect on beta-cell function and insulin sensitivity.
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Affiliation(s)
- E Nunes
- Faculty of Medicine, Institute of Physiology, Rua Larga, PT-3004-504, Coimbra, Portugal
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21
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Mitrani P, Srinivasan M, Dodds C, Patel MS. Autonomic involvement in the permanent metabolic programming of hyperinsulinemia in the high-carbohydrate rat model. Am J Physiol Endocrinol Metab 2007; 292:E1364-77. [PMID: 17227957 DOI: 10.1152/ajpendo.00672.2006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Exposure to a high-carbohydrate (HC) milk formula during the suckling period results in permanent metabolic programming of hyperinsulinemia in HC rats. Previous studies have shown that hyperinsulinemia in HC rats involves a programmed hyperresponsiveness to glucose. However, the immediate onset and persistence of enhanced insulin secretion throughout life suggests a role for numerous factors that control insulin secretion. Present in vivo and in vitro studies have shown a role for altered autonomic activity, including increased parasympathetic and decreased sympathetic activities, in the maintenance of hyperinsulinemia in 100-day-old HC rats. HC rats were shown to be more sensitive to cholinergic-induced potentiation of glucose-stimulated insulin secretion (GSIS) in response to acetylcholine and showed increased sensitivity to blockade of cholinergic-induced insulin secretion by the muscarinic-type 3 receptor-specific antagonist 4-diphenylacetoxy-N-methylpiperidine. In addition, HC rats were less sensitive to adrenergic-induced inhibition of insulin secretion by oxymetazoline, whereas treatment with yohimbine resulted in increased GSIS. Furthermore, HC rats showed greater reductions in plasma insulin levels after vagotomy, as well as an attenuation of yohimbine-induced potentiation of GSIS, suggesting that yohimbine-mediated changes are mediated by parasympathetic activity. Changes in autonomic regulation of GSIS are supported by increased mRNA levels of the parasympathetic signaling molecules muscarinic-type 3 receptor, phospholipase Cbeta1, and protein kinase C-alpha and decreased levels of alpha(2a)-adrenergic receptors in islets from adult HC rats. In conclusion, metabolic programming of hyperinsulinemia throughout adulthood of HC rats involves changes in autonomic activity in response to the HC dietary intervention in the suckling period.
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Affiliation(s)
- Paul Mitrani
- Department of Biochemistry, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, New York 14214, USA
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