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Janssen JAMJL. Overnutrition, Hyperinsulinemia and Ectopic Fat: It Is Time for A Paradigm Shift in the Management of Type 2 Diabetes. Int J Mol Sci 2024; 25:5488. [PMID: 38791525 PMCID: PMC11121669 DOI: 10.3390/ijms25105488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 05/12/2024] [Accepted: 05/15/2024] [Indexed: 05/26/2024] Open
Abstract
The worldwide incidence of prediabetes/type 2 has continued to rise the last 40 years. In the same period, the mean daily energy intake has increased, and the quality of food has significantly changed. The chronic exposure of pancreatic β-cells to calorie excess (excessive energy intake) and food additives may increase pancreatic insulin secretion, decrease insulin pulses and/or reduce hepatic insulin clearance, thereby causing chronic hyperinsulinemia and peripheral insulin resistance. Chronic calorie excess and hyperinsulinemia may promote lipogenesis, inhibit lipolysis and increase lipid storage in adipocytes. In addition, calorie excess and hyperinsulinemia can induce insulin resistance and contribute to progressive and excessive ectopic fat accumulation in the liver and pancreas by the conversion of excess calories into fat. The personal fat threshold hypothesis proposes that in susceptible individuals, excessive ectopic fat accumulation may eventually lead to hepatic insulin receptor resistance, the loss of pancreatic insulin secretion, hyperglycemia and the development of frank type 2 diabetes. Thus, type 2 diabetes seems (partly) to be caused by hyperinsulinemia-induced excess ectopic fat accumulation in the liver and pancreas. Increasing evidence further shows that interventions (hypocaloric diet and/or bariatric surgery), which remove ectopic fat in the liver and pancreas by introducing a negative energy balance, can normalize insulin secretion and glucose tolerance and induce the sustained biochemical remission of type 2 diabetes. This pathophysiological insight may have major implications and may cause a paradigm shift in the management of type 2 diabetes: avoiding/reducing ectopic fat accumulation in the liver and pancreas may both be essential to prevent and cure type 2 diabetes.
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Affiliation(s)
- Joseph A M J L Janssen
- Department of Internal Medicine, Erasmus Medical Center, 3015 GD Rotterdam, The Netherlands
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2
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Elgazzaz M, Berdasco C, Garai J, Baddoo M, Lu S, Daoud H, Zabaleta J, Mauvais-Jarvis F, Lazartigues E. Maternal Western diet programs cardiometabolic dysfunction and hypothalamic inflammation via epigenetic mechanisms predominantly in the male offspring. Mol Metab 2024; 80:101864. [PMID: 38159883 PMCID: PMC10806294 DOI: 10.1016/j.molmet.2023.101864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 12/04/2023] [Accepted: 12/22/2023] [Indexed: 01/03/2024] Open
Abstract
OBJECTIVE Maternal exposure during pregnancy is a strong determinant of offspring health outcomes. Such exposure induces changes in the offspring epigenome resulting in gene expression and functional changes. In this study, we investigated the effect of maternal Western hypercaloric diet (HCD) programming during the perinatal period on neuronal plasticity and cardiometabolic health in adult offspring. METHODS C57BL/6J dams were fed HCD for 1 month prior to mating with regular diet (RD) sires and kept on the same diet throughout pregnancy and lactation. At weaning, offspring were maintained on either HCD or RD for 3 months resulting in 4 treatment groups that underwent cardiometabolic assessments. DNA and RNA were extracted from the hypothalamus to perform whole genome methylation, mRNA, and miRNA sequencing followed by bioinformatic analyses. RESULTS Maternal programming resulted in male-specific hypertension and hyperglycemia, with both males and females showing increased sympathetic tone to the vasculature. Surprisingly, programmed male offspring fed HCD in adulthood exhibited lower glucose levels, less insulin resistance, and leptin levels compared to non-programmed HCD-fed male mice. Hypothalamic genes involved in inflammation and type 2 diabetes were targeted by differentially expressed miRNA, while genes involved in glial and astrocytic differentiation were differentially methylated in programmed male offspring. These data were supported by our findings of astrogliosis, microgliosis and increased microglial activation in programmed males in the paraventricular nucleus (PVN). Programming induced a protective effect in male mice fed HCD in adulthood, resulting in lower protein levels of hypothalamic TGFβ2, NF-κB2, NF-κBp65, Ser-pIRS1, and GLP1R compared to non-programmed HCD-fed males. Although TGFβ2 was upregulated in male mice exposed to HCD pre- or post-natally, only blockade of the brain TGFβ receptor in RD-HCD mice improved glucose tolerance and a trend to weight loss. CONCLUSIONS Our study shows that maternal HCD programs neuronal plasticity in the offspring and results in male-specific hypertension and hyperglycemia associated with hypothalamic inflammation in mechanisms and pathways distinct from post-natal HCD exposure. Together, our data unmask a compensatory role of HCD programming, likely via priming of metabolic pathways to handle excess nutrients in a more efficient way.
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Affiliation(s)
- Mona Elgazzaz
- Cardiovascular Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA; Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA; Southeast Louisiana Veterans Health Care System, New Orleans, LA 70119, USA; Genetics Unit, Department of Histology and Cell Biology, Faculty of Medicine, Suez Canal University, Ismailia, 41522, Egypt
| | - Clara Berdasco
- Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA; Southeast Louisiana Veterans Health Care System, New Orleans, LA 70119, USA
| | - Jone Garai
- Department of Interdisciplinary Oncology and Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Melody Baddoo
- Department of Pathology and Laboratory Medicine/Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Shiping Lu
- Center for Translational Research in Infection and Inflammation, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Hisham Daoud
- School of Computer and Cyber Sciences, Augusta University, Augusta, GA 30901, USA
| | - Jovanny Zabaleta
- Department of Interdisciplinary Oncology and Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Franck Mauvais-Jarvis
- Southeast Louisiana Veterans Health Care System, New Orleans, LA 70119, USA; Department of Medicine, Section of Endocrinology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Eric Lazartigues
- Cardiovascular Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA; Department of Pharmacology & Experimental Therapeutics, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA; Southeast Louisiana Veterans Health Care System, New Orleans, LA 70119, USA; Neuroscience Center of Excellence, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA.
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3
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Hong HJ, Joung KH, Kim YK, Choi MJ, Kang SG, Kim JT, Kang YE, Chang JY, Moon JH, Jun S, Ro HJ, Lee Y, Kim H, Park JH, Kang BE, Jo Y, Choi H, Ryu D, Lee CH, Kim H, Park KS, Kim HJ, Shong M. Mitoribosome insufficiency in β cells is associated with type 2 diabetes-like islet failure. EXPERIMENTAL & MOLECULAR MEDICINE 2022; 54:932-945. [PMID: 35804190 PMCID: PMC9355985 DOI: 10.1038/s12276-022-00797-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 02/22/2022] [Accepted: 03/14/2022] [Indexed: 12/04/2022]
Abstract
Genetic variations in mitoribosomal subunits and mitochondrial transcription factors are related to type 2 diabetes. However, the role of islet mitoribosomes in the development of type 2 diabetes has not been determined. We investigated the effects of the mitoribosomal gene on β-cell function and glucose homeostasis. Mitoribosomal gene expression was analyzed in datasets from the NCBI GEO website (GSE25724, GSE76894, and GSE76895) and the European Nucleotide Archive (ERP017126), which contain the transcriptomes of type 2 diabetic and nondiabetic organ donors. We found deregulation of most mitoribosomal genes in islets from individuals with type 2 diabetes, including partial downregulation of CRIF1. The phenotypes of haploinsufficiency in a single mitoribosomal gene were examined using β-cell-specific Crif1 (Mrpl59) heterozygous-deficient mice. Crif1beta+/− mice had normal glucose tolerance, but their islets showed a loss of first-phase glucose-stimulated insulin secretion. They also showed increased β-cell mass associated with higher expression of Reg family genes. However, Crif1beta+/− mice showed earlier islet failure in response to high-fat feeding, which was exacerbated by aging. Haploinsufficiency of a single mitoribosomal gene predisposes rodents to glucose intolerance, which resembles the early stages of type 2 diabetes in humans. Disruptions in the mitochondrial protein synthesis machinery give rise to metabolic disturbances that lay the foundation for type 2 diabetes. As physiological glucose levels rise, the energy-generating machinery of the mitochondria responds with increased activity, which stimulates insulin secretion. Many proteins responsible for mitochondrial metabolism are produced by ribosomes within this cellular organelle. Researchers led by Hyun Jin Kim and Minho Shong at Chungnam National University, Daejon, South Korea, have determined that mutations affecting a mitochondrial ribosomal protein called CRIF1 can lead to impaired insulin release. Mice with reduced CRIF1 were initially healthy, but as they aged, exhibited signs of impaired pancreatic function similar to those seen in patients with early-stage diabetes. This process was accelerated by consumption of a high-fat diet, and the researchers propose that this mechanism may be directly relevant to human disease.
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Affiliation(s)
- Hyun Jung Hong
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea.,Department of Medical Science, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Kyong Hye Joung
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea.,Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Yong Kyung Kim
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Min Jeong Choi
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Seul Gi Kang
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Jung Tae Kim
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea.,Department of Medical Science, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Yea Eun Kang
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea.,Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Joon Young Chang
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea.,Department of Medical Science, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Joon Ho Moon
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Sangmi Jun
- Center for Research Equipment, Korea Basic Science Institute, Cheongju, 28119, Korea.,Convergent Research Center for Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Hyun-Joo Ro
- Center for Research Equipment, Korea Basic Science Institute, Cheongju, 28119, Korea.,Convergent Research Center for Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Yujeong Lee
- Center for Research Equipment, Korea Basic Science Institute, Cheongju, 28119, Korea.,Convergent Research Center for Emerging Virus Infection, Korea Research Institute of Chemical Technology, Daejeon, 34114, Korea
| | - Hyeongseok Kim
- Department of Biochemistry, Chungnam National University School of Medicine, Daejeon, 35015, Korea
| | - Jae-Hyung Park
- Department of Physiology, Keimyung University School of Medicine, Daegu, 704-200, Korea
| | - Baeki E Kang
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Korea
| | - Yunju Jo
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Korea
| | - Heejung Choi
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Korea
| | - Dongryeol Ryu
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Korea.,Biomedical Institute for Convergence at SKKU (BICS), Sungkyunkwan University, Suwon, 16419, Korea.,Samsung Biomedical Research Institute, Samsung Medical Center, Seoul, 06351, Korea
| | - Chul-Ho Lee
- Animal Model Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 34141, Korea
| | - Hail Kim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Korea
| | - Kyu-Sang Park
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, 26426, Korea
| | - Hyun Jin Kim
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea. .,Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, 35015, Korea.
| | - Minho Shong
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon, 35015, Korea. .,Department of Medical Science, Chungnam National University School of Medicine, Daejeon, 35015, Korea. .,Department of Internal Medicine, Chungnam National University School of Medicine, Daejeon, 35015, Korea.
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Kahn SE, Chen YC, Esser N, Taylor AJ, van Raalte DH, Zraika S, Verchere CB. The β Cell in Diabetes: Integrating Biomarkers With Functional Measures. Endocr Rev 2021; 42:528-583. [PMID: 34180979 PMCID: PMC9115372 DOI: 10.1210/endrev/bnab021] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Indexed: 02/08/2023]
Abstract
The pathogenesis of hyperglycemia observed in most forms of diabetes is intimately tied to the islet β cell. Impairments in propeptide processing and secretory function, along with the loss of these vital cells, is demonstrable not only in those in whom the diagnosis is established but typically also in individuals who are at increased risk of developing the disease. Biomarkers are used to inform on the state of a biological process, pathological condition, or response to an intervention and are increasingly being used for predicting, diagnosing, and prognosticating disease. They are also proving to be of use in the different forms of diabetes in both research and clinical settings. This review focuses on the β cell, addressing the potential utility of genetic markers, circulating molecules, immune cell phenotyping, and imaging approaches as biomarkers of cellular function and loss of this critical cell. Further, we consider how these biomarkers complement the more long-established, dynamic, and often complex measurements of β-cell secretory function that themselves could be considered biomarkers.
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Affiliation(s)
- Steven E Kahn
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, VA Puget Sound Health Care System and University of Washington, Seattle, 98108 WA, USA
| | - Yi-Chun Chen
- BC Children's Hospital Research Institute and Centre for Molecular Medicine and Therapeutics, Vancouver, BC, V5Z 4H4, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
| | - Nathalie Esser
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, VA Puget Sound Health Care System and University of Washington, Seattle, 98108 WA, USA
| | - Austin J Taylor
- BC Children's Hospital Research Institute and Centre for Molecular Medicine and Therapeutics, Vancouver, BC, V5Z 4H4, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
| | - Daniël H van Raalte
- Department of Internal Medicine, Amsterdam University Medical Center (UMC), Vrije Universiteit (VU) University Medical Center, 1007 MB Amsterdam, The Netherlands.,Department of Experimental Vascular Medicine, Amsterdam University Medical Center (UMC), Academic Medical Center, 1007 MB Amsterdam, The Netherlands
| | - Sakeneh Zraika
- Division of Metabolism, Endocrinology and Nutrition, Department of Medicine, VA Puget Sound Health Care System and University of Washington, Seattle, 98108 WA, USA
| | - C Bruce Verchere
- BC Children's Hospital Research Institute and Centre for Molecular Medicine and Therapeutics, Vancouver, BC, V5Z 4H4, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, V5Z 4H4, Canada.,Department of Surgery, University of British Columbia, Vancouver, BC, V5Z 4H4, Canada
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Abstract
Hypoxia can be defined as a relative deficiency in the amount of oxygen reaching the tissues. Hypoxia-inducible factors (HIFs) are critical regulators of the mammalian response to hypoxia. In normal circumstances, HIF-1α protein turnover is rapid, and hyperglycemia further destabilizes the protein. In addition to their role in diabetes pathogenesis, HIFs are implicated in development of the microvascular and macrovascular complications of diabetes. Improving glucose control in people with diabetes increases HIF-1α protein and has wide-ranging benefits, some of which are at least partially mediated by HIF-1α. Nevertheless, most strategies to improve diabetes or its complications via regulation of HIF-1α have not currently proven to be clinically useful. The intersection of HIF biology with diabetes is a complex area in which many further questions remain, especially regarding the well-conducted studies clearly describing discrepant effects of different methods of increasing HIF-1α, even within the same tissues. This Review presents a brief overview of HIFs; discusses the range of evidence implicating HIFs in β cell dysfunction, diabetes pathogenesis, and diabetes complications; and examines the differing outcomes of HIF-targeting approaches in these conditions.
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Affiliation(s)
- Jenny E Gunton
- Centre for Diabetes, Obesity and Endocrinology, Westmead Institute for Medical Research, Westmead, New South Wales, Australia.,Westmead Hospital, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
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6
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Alcazar O, Alvarez A, Ricordi C, Linetsky E, Buchwald P. The Effect of Recovery Warm-up Time Following Cold Storage on the Dynamic Glucose-stimulated Insulin Secretion of Isolated Human Islets. Cell Transplant 2021; 29:963689720908278. [PMID: 32223315 PMCID: PMC7444215 DOI: 10.1177/0963689720908278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Standardized islet characterization assays that can provide results in a timely manner are essential for successful islet cell transplantation. A critical component of islet cell quality is β-cell function, and perifusion-based assessments of dynamic glucose-stimulated insulin secretion (GSIS) are the most informative method to assess this, as they provide the most complex in vitro evaluation of GSIS. However, protocols used vary considerably among centers and investigators as they often use different low- and high-glucose concentrations, exposure-times, flow-rates, oxygen concentrations, islet numbers, analytical methods, measurement units, and instruments, which result in different readouts and make comparisons across platforms difficult. Additionally, the conditions of islet storage and shipment prior to assessment may also affect islet function. Establishing improved standardized protocols for perifusion GSIS assays should be an integral part of the ongoing effort to increase the rigor of human islet studies. Here, we performed detailed evaluation of GSIS of human islets using a fully automated multichannel perifusion instrument following various warm-up recovery times after cold storage that corresponds to current shipping conditions (8°C). We found that recovery times shorter than 18 h (overnight) resulted in impaired insulin secretion. While the effects were relatively moderate on second-phase insulin secretion, first-phase peaks were restored only following 18-h incubation. Hence, the biphasic profile of dynamic GSIS was considerably affected when islets were not allowed to recover for a sufficient time after being maintained in cold. Accordingly, while cold storage might improve islet cell survival during shipment and prolong the length of culture, functional assessments should be performed only after allowing for at least overnight recovery at physiological temperatures.
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Affiliation(s)
- Oscar Alcazar
- Diabetes Research Institute, Miller School of Medicine, University of Miami, FL, USA
| | - Alejandro Alvarez
- Diabetes Research Institute, Miller School of Medicine, University of Miami, FL, USA
| | - Camillo Ricordi
- Diabetes Research Institute, Miller School of Medicine, University of Miami, FL, USA.,Department of Surgery, Division of Cellular Transplantation, cGMP Advanced Cell and Biologic Manufacturing Facility, Miller School of Medicine, University of Miami, FL, USA
| | - Elina Linetsky
- Diabetes Research Institute, Miller School of Medicine, University of Miami, FL, USA.,Department of Surgery, Division of Cellular Transplantation, cGMP Advanced Cell and Biologic Manufacturing Facility, Miller School of Medicine, University of Miami, FL, USA
| | - Peter Buchwald
- Diabetes Research Institute, Miller School of Medicine, University of Miami, FL, USA.,Department of Molecular and Cellular Pharmacology, Miller School of Medicine, University of Miami, FL, USA
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7
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Islam MS. Stimulus-Secretion Coupling in Beta-Cells: From Basic to Bedside. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:943-963. [PMID: 31646540 DOI: 10.1007/978-3-030-12457-1_37] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Insulin secretion in humans is usually induced by mixed meals, which upon ingestion, increase the plasma concentration of glucose, fatty acids, amino acids, and incretins like glucagon-like peptide 1. Beta-cells can stay in the off-mode, ready-mode or on-mode; the mode-switching being determined by the open state probability of the ATP-sensitive potassium channels, and the activity of enzymes like glucokinase, and glutamate dehydrogenase. Mitochondrial metabolism is critical for insulin secretion. A sound understanding of the intermediary metabolism, electrophysiology, and cell signaling is essential for comprehension of the entire spectrum of the stimulus-secretion coupling. Depolarization brought about by inhibition of the ATP sensitive potassium channel, together with the inward depolarizing currents through the transient receptor potential (TRP) channels, leads to electrical activities, opening of the voltage-gated calcium channels, and exocytosis of insulin. Calcium- and cAMP-signaling elicited by depolarization, and activation of G-protein-coupled receptors, including the free fatty acid receptors, are intricately connected in the form of networks at different levels. Activation of the glucagon-like peptide 1 receptor augments insulin secretion by amplifying calcium signals by calcium induced calcium release (CICR). In the treatment of type 2 diabetes, use of the sulfonylureas that act on the ATP sensitive potassium channel, damages the beta cells, which eventually fail; these drugs do not improve the cardiovascular outcomes. In contrast, drugs acting through the glucagon-like peptide-1 receptor protect the beta-cells, and improve cardiovascular outcomes. The use of the glucagon-like peptide 1 receptor agonists is increasing and that of sulfonylurea is decreasing. A better understanding of the stimulus-secretion coupling may lead to the discovery of other molecular targets for development of drugs for the prevention and treatment of type 2 diabetes.
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Affiliation(s)
- Md Shahidul Islam
- Department of Clinical Science and Education, Södersjukhuset, Research Center, Karolinska Institutet, Stockholm, Sweden. .,Department of Emergency Care and Internal Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
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8
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Calcium Signaling in ß-cell Physiology and Pathology: A Revisit. Int J Mol Sci 2019; 20:ijms20246110. [PMID: 31817135 PMCID: PMC6940736 DOI: 10.3390/ijms20246110] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 11/28/2019] [Accepted: 12/02/2019] [Indexed: 12/12/2022] Open
Abstract
Pancreatic beta (β) cell dysfunction results in compromised insulin release and, thus, failed regulation of blood glucose levels. This forms the backbone of the development of diabetes mellitus (DM), a disease that affects a significant portion of the global adult population. Physiological calcium (Ca2+) signaling has been found to be vital for the proper insulin-releasing function of β-cells. Calcium dysregulation events can have a dramatic effect on the proper functioning of the pancreatic β-cells. The current review discusses the role of calcium signaling in health and disease in pancreatic β-cells and provides an in-depth look into the potential role of alterations in β-cell Ca2+ homeostasis and signaling in the development of diabetes and highlights recent work that introduced the current theories on the connection between calcium and the onset of diabetes.
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9
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Synthesis of new arylsulfonylspiroimidazolidine-2ʹ,4ʹ-diones and study of their effect on stimulation of insulin release from MIN6 cell line, inhibition of human aldose reductase, sorbitol accumulations in various tissues and oxidative stress. Eur J Med Chem 2019; 168:154-175. [DOI: 10.1016/j.ejmech.2019.02.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Revised: 02/01/2019] [Accepted: 02/10/2019] [Indexed: 11/18/2022]
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10
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Klec C, Madreiter-Sokolowski CT, Stryeck S, Sachdev V, Duta-Mare M, Gottschalk B, Depaoli MR, Rost R, Hay J, Waldeck-Weiermair M, Kratky D, Madl T, Malli R, Graier WF. Glycogen Synthase Kinase 3 Beta Controls Presenilin-1-Mediated Endoplasmic Reticulum Ca²⁺ Leak Directed to Mitochondria in Pancreatic Islets and β-Cells. Cell Physiol Biochem 2019; 52:57-75. [PMID: 30790505 PMCID: PMC6459368 DOI: 10.33594/000000005] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 01/15/2019] [Indexed: 01/09/2023] Open
Abstract
Background/Aims In pancreatic β-cells, the intracellular Ca2+ homeostasis is an essential regulator of the cells’ major functions. The endoplasmic reticulum (ER) as interactive intracellular Ca2+ store balances cellular Ca2+. In this study basal ER Ca2+ homeostasis was evaluated in order to reveal potential β-cell-specificity of ER Ca2+ handling and its consequences for mitochondrial Ca2+, ATP and respiration. Methods The two pancreatic cell lines INS-1 and MIN-6, freshly isolated pancreatic islets, and the two non-pancreatic cell lines HeLA and EA.hy926 were used. Cytosolic, ER and mitochondrial Ca2+ and ATP measurements were performed using single cell fluorescence microscopy and respective (genetically-encoded) sensors/dyes. Mitochondrial respiration was monitored by respirometry. GSK3β activity was measured with ELISA. Results An atypical ER Ca2+ leak was observed exclusively in pancreatic islets and β-cells. This continuous ER Ca2+ efflux is directed to mitochondria and increases basal respiration and organellar ATP levels, is established by GSK3β-mediated phosphorylation of presenilin-1, and is prevented by either knockdown of presenilin-1 or an inhibition/knockdown of GSK3β. Expression of a presenlin-1 mutant that mimics GSK3β-mediated phosphorylation established a β-cell-like ER Ca2+ leak in HeLa and EA.hy926 cells. The ER Ca2+ loss in β-cells was compensated at steady state by Ca2+ entry that is linked to the activity of TRPC3. Conclusion Pancreatic β-cells establish a cell-specific ER Ca2+ leak that is under the control of GSK3β and directed to mitochondria, thus, reflecting a cell-specific intracellular Ca2+ handling for basal mitochondrial activity.
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Affiliation(s)
- Christiane Klec
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Corina T Madreiter-Sokolowski
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Sarah Stryeck
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Vinay Sachdev
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria.,Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Madalina Duta-Mare
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Benjamin Gottschalk
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Maria R Depaoli
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Rene Rost
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Jesse Hay
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria.,University of Montana, Division of Biological Sciences, Center for Structural & Functional Neuroscience, Missoula, MT, USA
| | - Markus Waldeck-Weiermair
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria
| | - Dagmar Kratky
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Tobias Madl
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Roland Malli
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria.,BioTechMed, Graz, Austria
| | - Wolfgang F Graier
- Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria.,BioTechMed, Graz, Austria.,Molecular Biology and Biochemistry, Gottfried Schatz Research Center for Cellular Signaling, Metabolism & Aging, Medical University of Graz, Graz, Austria,
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11
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Dhillon J, Lee JY, Mattes RD. The cephalic phase insulin response to nutritive and low-calorie sweeteners in solid and beverage form. Physiol Behav 2017; 181:100-109. [PMID: 28899680 PMCID: PMC5634742 DOI: 10.1016/j.physbeh.2017.09.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 09/08/2017] [Accepted: 09/08/2017] [Indexed: 12/22/2022]
Abstract
The purpose of the study was to examine the role of the cephalic phase insulin response (CPIR) following exposure to nutritive and low-calorie sweeteners in solid and beverage form in overweight and obese adults. In addition, the role of learning on the CPIR to nutritive and low-calorie sweetener exposure was tested. Sixty-four overweight and obese adults (age: 18-50years, BMI: 24-37kg/m2, body fat percentage>25% for men and >32% for women) were sham-fed (at 2-minute intervals for 14min) a randomly assigned test load comprised of a nutritive (sucrose) or low-calorie sweetener (sucralose) in beverage or solid form in phase 1 of the study. A 2-3ml blood sample was collected before and 2, 6, 10, 14, 61, 91 and 121min after oral exposure for serum insulin and glucose analysis. During phase 2, participants underwent a 2-week training period to facilitate associative learning between the sensory properties of test loads and their post-ingestive effects. In phase 3, participants were retested for their cephalic phase responses as in phase 1. Participants were classified as responders if they demonstrated a positive insulin response (rise of serum insulin above baseline i.e. Δ insulin) 2min post-stimulus in phase 1. Among responders exposed to the same sweetener in Phases 1 and 3, the proportion of participants that displayed a rise of insulin with oral exposure to sucralose was significantly greater when the stimulus was in the solid form compared to the beverage form. Sucralose and sucrose exposure elicited similarly significant increases in serum insulin 2min after exposure and significant decreases after 2min in responders in both food forms. The solid food form elicited greater CPIR over 2, 6 and 10min than the beverage form. There was no effect of learning on insulin responses after training. The results indicate the presence of a significant CPIR in a subset of individuals with overweight or obesity after oral exposure to sucralose, especially when present in solid food form. Future studies must confirm the reliability of this response.
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Affiliation(s)
- Jaapna Dhillon
- Department of Nutrition Science, Purdue University, 226 Stone Hall, 700 W State Street, West Lafayette 47907, IN, USA.
| | - Janice Y Lee
- Department of Nutrition Science, Purdue University, 226 Stone Hall, 700 W State Street, West Lafayette 47907, IN, USA.
| | - Richard D Mattes
- Department of Nutrition Science, Purdue University, 226 Stone Hall, 700 W State Street, West Lafayette 47907, IN, USA.
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12
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Pepe GJ, Maniu A, Aberdeen G, Lynch TJ, Kim SO, Nadler J, Albrecht ED. Insulin resistance elicited in postpubertal primate offspring deprived of estrogen in utero. Endocrine 2016; 54:788-797. [PMID: 27770396 PMCID: PMC6038696 DOI: 10.1007/s12020-016-1145-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 10/05/2016] [Indexed: 12/25/2022]
Abstract
We recently demonstrated that offspring delivered to baboons deprived of estrogen during the second half of gestation exhibited insulin resistance prior to onset of puberty. Because gonadal hormones have a profound effect on insulin action and secretion in adults, we determined whether insulin resistance is retained after initiation of gonadal secretion of testosterone and estradiol. Glucose tolerance tests were performed in postpubertal baboon offspring of untreated and letrozole-treated animals (serum estradiol reduced >95 %). Basal fasting levels of insulin (P < 0.05) and peak 1 min and 1 + 3 + 5 min levels of glucose after glucose tolerance tests challenge (P < 0.03) were greater in offspring delivered to letrozole-treated, estrogen-deprived baboons than untreated animals. Moreover, the value for the HOMA-IR, an accepted index of insulin resistance, was 2-fold greater (P < 0.05) in offspring delivered to baboons treated with letrozole than in untreated animals. Collectively these results support the proposal that estrogen normally has an important role in programming mechanisms in utero within the developing fetus that lead to insulin sensitivity after birth.
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Affiliation(s)
- Gerald J Pepe
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA, USA.
| | - Adina Maniu
- Department of Obstetrics/Gynecology/Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Graham Aberdeen
- Department of Obstetrics/Gynecology/Reproductive Sciences, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Terrie J Lynch
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Soon Ok Kim
- Department of Physiological Sciences, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Jerry Nadler
- Department of Internal Medicine, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Eugene D Albrecht
- Departments of Obstetrics/Gynecology/Reproductive Sciences and Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
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13
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Yabe D, Kuroe A, Watanabe K, Iwasaki M, Hamasaki A, Hamamoto Y, Harada N, Yamane S, Lee S, Murotani K, Deacon CF, Holst JJ, Hirano T, Inagaki N, Kurose T, Seino Y. Early phase glucagon and insulin secretory abnormalities, but not incretin secretion, are similarly responsible for hyperglycemia after ingestion of nutrients. J Diabetes Complications 2015; 29:413-21. [PMID: 25613093 DOI: 10.1016/j.jdiacomp.2014.12.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 01/08/2023]
Abstract
AIMS Hypersecretion of glucagon and reduced insulin secretion both contribute to hyperglycemia in type 2 diabetes (T2DM). However, the relative contributions of impaired glucagon and insulin secretions in glucose excursions at the various stages of T2DM development remain to be determined. METHODS The responses of glucagon and insulin as well as those of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) were examined before and after ingestion of glucose or mixed meal in Japanese subjects with normal or impaired glucose tolerance (NGT and IGT) and in non-obese, untreated T2DM of short duration. RESULTS In OGTT, T2DM showed a rise in glucagon at 0-30 min, unlike NGT and IGT, along with reduced insulin. In MTT, all three groups showed a rise in glucagon at 0-30 min, with that in T2DM being highest, while T2DM showed a significant reduction in insulin. Linear regression analyses revealed that glucose area under the curve (AUC)0-120 min was associated with glucagon-AUC0-30 min and insulin-AUC0-30 min in both OGTT and MTT. Total and biologically intact GIP and GLP-1 levels were similar among the three groups. CONCLUSIONS Disordered early phase insulin and glucagon secretions but not incretin secretion are involved in hyperglycemia after ingestion of nutrients in T2DM of even a short duration.
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Affiliation(s)
- Daisuke Yabe
- Center for Diabetes, Endocrinology, and Metabolism, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan; Center for Metabolism and Clinical Nutrition, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan; Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, 1-5-6 Minatojimaminamimachi, Chuo-ku, Kobe 650-0047, Japan.
| | - Akira Kuroe
- Center for Diabetes, Endocrinology, and Metabolism, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan
| | - Koin Watanabe
- Center for Diabetes, Endocrinology, and Metabolism, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan
| | - Masahiro Iwasaki
- Center for Metabolism and Clinical Nutrition, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan; Division of Molecular and Metabolic Medicine, Department of Physiology and Cell Biology, Kobe University Graduate School of Medicine, 1-5-6 Minatojimaminamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Akihiro Hamasaki
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, 54 Shogo-in Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Yoshiyuki Hamamoto
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, 54 Shogo-in Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Norio Harada
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, 54 Shogo-in Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Shunsuke Yamane
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, 54 Shogo-in Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Soushou Lee
- Department of Diabetes, Metabolism and Endocrinology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Kenta Murotani
- Center for Advanced Medicine and Clinical Research, Nagoya University Hospital, Tsurumai-cho, Showa-ku, Nagoya 466-8560, Japan
| | - Carolyn F Deacon
- Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, Blegdamsvej 3, 2200 Copenhagen N, Denmark
| | - Jens J Holst
- Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3, Blegdamsvej 3, 2200 Copenhagen N, Denmark
| | - Tsutomu Hirano
- Department of Diabetes, Metabolism and Endocrinology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Nobuya Inagaki
- Department of Diabetes, Endocrinology and Nutrition, Graduate School of Medicine, Kyoto University, 54 Shogo-in Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Takeshi Kurose
- Center for Diabetes, Endocrinology, and Metabolism, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan
| | - Yutaka Seino
- Center for Diabetes, Endocrinology, and Metabolism, Kansai Electric Power Hospital, 2-1-7 Fukushima-ku, Osaka 553-0003, Japan.
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14
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Nwose OM, Jones MR. Atypical mechanism of glucose modulation by colesevelam in patients with type 2 diabetes. CLINICAL MEDICINE INSIGHTS-ENDOCRINOLOGY AND DIABETES 2013; 6:75-9. [PMID: 24348081 PMCID: PMC3864737 DOI: 10.4137/cmed.s12590] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Colesevelam's glucose-lowering mechanism of action is not completely understood. Clinical trials of colesevelam suggest that its mechanism, and often adverse effects, differ from those of other oral antidiabetes drugs. Colesevelam does not affect insulin sensitivity (unlike thiazolidinediones), insulin secretion (unlike sulfonylureas and meglitinides), or early insulin response or glucagon (unlike dipeptidyl peptidase-4 inhibitors). Colesevelam may have some effect on glucose absorption, but likely via a different mechanism than α-glucosidase inhibitors. Colesevelam and metformin have similarities regarding hepatic glucose production, but divergent effects on gluconeogenesis versus glycogenolysis, suggesting differing mechanisms of drug action for improving glycemic control. Colesevelam is thought to be a portal glucagon-like peptide-1 (GLP-1) secretagogue with primarily hepatic effects. Bile acid binding by colesevelam leads to TGR5 activation, increased secretion of GLP-1 or other incretins, and inhibition of hepatic glycogenolysis. Colesevelam's mechanism of action appears to be atypical of other antidiabetes medications, making it a potentially suitable component of many combination regimens in the treatment of type 2 diabetes.
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Affiliation(s)
- Oliseyenum M Nwose
- Executive Medical Director, Therapeutic Area Head, Hypertension, Metabolism and Pain, Daiichi Sankyo, Inc., Parsippany, New Jersey, USA
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15
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Cheng K, Delghingaro-Augusto V, Nolan CJ, Turner N, Hallahan N, Andrikopoulos S, Gunton JE. High passage MIN6 cells have impaired insulin secretion with impaired glucose and lipid oxidation. PLoS One 2012; 7:e40868. [PMID: 22808281 PMCID: PMC3396628 DOI: 10.1371/journal.pone.0040868] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 06/18/2012] [Indexed: 12/20/2022] Open
Abstract
Type 2 diabetes is a metabolic disorder characterized by the inability of beta-cells to secrete enough insulin to maintain glucose homeostasis. MIN6 cells secrete insulin in response to glucose and other secretagogues, but high passage (HP) MIN6 cells lose their ability to secrete insulin in response to glucose. We hypothesized that metabolism of glucose and lipids were defective in HP MIN6 cells causing impaired glucose stimulated insulin secretion (GSIS). HP MIN6 cells had no first phase and impaired second phase GSIS indicative of global functional impairment. This was coupled with a markedly reduced ATP content at basal and glucose stimulated states. Glucose uptake and oxidation were higher at basal glucose but ATP content failed to increase with glucose. HP MIN6 cells had decreased basal lipid oxidation. This was accompanied by reduced expressions of Glut1, Gck, Pfk, Srebp1c, Ucp2, Sirt3, Nampt. MIN6 cells represent an important model of beta cells which, as passage numbers increased lost first phase but retained partial second phase GSIS, similar to patients early in type 2 diabetes onset. We believe a number of gene expression changes occurred to produce this defect, with emphasis on Sirt3 and Nampt, two genes that have been implicated in maintenance of glucose homeostasis.
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Affiliation(s)
- Kim Cheng
- Diabetes and Transcription Factors Group, Garvan Institute of Medical Research (GIMR), Sydney, NSW, Australia
| | | | | | - Nigel Turner
- Diabetes and Obesity Program, Garvan Institute of Medical Research (GIMR), Sydney, NSW, Australia
| | - Nicole Hallahan
- Diabetes and Obesity Program, Garvan Institute of Medical Research (GIMR), Sydney, NSW, Australia
| | | | - Jenny E. Gunton
- Diabetes and Transcription Factors Group, Garvan Institute of Medical Research (GIMR), Sydney, NSW, Australia
- Faculty of Medicine, University of Sydney, Sydney, NSW, Australia
- St. Vincent’s Clinical School, University of New South Wales, Sydney, NSW, Australia
- Department of Diabetes and Endocrinology, Westmead Hospital, Sydney, NSW, Australia
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16
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Abstract
This review focuses on the methods accessing β-cell function. β-cell failure is the critical step in the development of type 2 diabetes. Therefore, assessment of β-cell function is an important part of the evaluation and treatment of diabetic patients. However, it is not easy because of complex interaction between multiple tissues. Several parameters should be considered, such as glucose level and insulin sensitivity of diverse insulin target tissues to assess β-cell function. To overcome these difficulties, several invasive or non-invasive methods have been developed to assess β-cell function for clinical or research purposes.
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Affiliation(s)
- Cheol Soo Choi
- Lee Gil Ya Cancer and Diabetes Institute, Gachon University of Medicine and Science, Incheon, South Korea
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17
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Guo LX, Xia ZN, Gao X, Yin F, Liu JH. Glucagon-like peptide 1 receptor plays a critical role in geniposide-regulated insulin secretion in INS-1 cells. Acta Pharmacol Sin 2012; 33:237-41. [PMID: 22101168 DOI: 10.1038/aps.2011.146] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
AIM To explore the role of the glucagon-like peptide 1 receptor (GLP-1R) in geniposide regulated insulin secretion in rat INS-1 insulinoma cells. METHODS Rat INS-1 insulinoma cells were cultured. The content of insulin in the culture medium was measured with ELISA assay. GLP-1R gene in INS-1 cells was knocked down with shRNA interference. The level of GLP-1R protein in INS-1 cells was measured with Western blotting. RESULTS Geniposide (0.01-100 μmol/L) increased insulin secretion from INS-1 cells in a concentration-dependent manner. Geniposide (10 μmol/L) enhanced acute insulin secretion in response to both the low (5.5 mmol/L) and moderately high levels (11 mmol/L) of glucose. Blockade of GLP-1R with the GLP-1R antagonist exendin (9-39) (200 nmol/L) or knock-down of GLP-1R with shRNA interference in INS-1 cells decreased the effect of geniposide (10 μmol/L) on insulin secretion stimulated by glucose (5.5 mmol/L). CONCLUSION Geniposide increases insulin secretion through glucagon-like peptide 1 receptors in rat INS-1 insulinoma cells.
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18
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Xie L, Hoffman RP, Veng-Pedersen P. Population analysis of ethnicity and first-phase insulin release. Diabetes Res Clin Pract 2010; 89:243-9. [PMID: 20570007 PMCID: PMC4445972 DOI: 10.1016/j.diabres.2010.04.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 04/22/2010] [Accepted: 04/29/2010] [Indexed: 11/25/2022]
Abstract
OBJECTIVE A mechanistic, physiologically-based pharmacokinetic (PK/PD) model was developed to describe the biphasic insulin release and evaluate the racial effects on the glucose-insulin kinetics in response to intravenous glucose. METHODS Fifteen African-American and 18 Caucasian children and adolescents between 8 and 18 years of age were enrolled in the study. Intravenous bolus of glucose (250 mg/kg) was administered and blood samples collected at frequent intervals for three hours following the glucose injection. A nonlinear mixed-effect population kinetic analysis with covariate structure was performed using Monolix. RESULTS A significantly higher initial insulin secretion from a readily releasable pool, which is responsible for the first-phase insulin secretion, was detected in African-Americans compared to Caucasians (p<0.05). CONCLUSIONS The proposed kinetic model is able to describe the glucose-stimulated insulin response, account for the first-phase insulin release and identify a racially-based pharmacokinetic difference in insulin's biphasic secretion behavior. It is hypothesized that the first-phase insulin component may play an important role in the development of type 2 diabetes. The proposed mechanistic model provides a quantitative analysis of the biphasic insulin release that may be useful in the early detection of diabetes.
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Affiliation(s)
- Lanyi Xie
- Division of Pharmaceutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, United States
| | - Robert P. Hoffman
- Department of Pediatrics (R.P.H.), College of Medicine, Ohio State University, Columbus, OH 43205, United States
| | - Peter Veng-Pedersen
- Division of Pharmaceutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, United States
- Corresponding author. Tel.: +1 319 335 8792; fax: +1 319 335 9349. (P. Veng-Pedersen)
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19
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Wu CZ, Pei D, Hsieh AT, Wang K, Lin JD, Lee LH, Chu YM, Hsiao FC, Pei C, Hsia TL. Comparison of insulin sensitivity, glucose sensitivity, and first phase insulin secretion in patients treated with repaglinide or gliclazide. Arch Pharm Res 2010; 33:411-6. [DOI: 10.1007/s12272-010-0310-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2009] [Revised: 12/17/2009] [Accepted: 12/21/2009] [Indexed: 12/01/2022]
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20
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Healy JA, Nilsson KR, Hohmeier HE, Berglund J, Davis J, Hoffman J, Kohler M, Li LS, Berggren PO, Newgard CB, Bennett V. Cholinergic augmentation of insulin release requires ankyrin-B. Sci Signal 2010; 3:ra19. [PMID: 20234002 DOI: 10.1126/scisignal.2000771] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Parasympathetic stimulation of pancreatic islets augments glucose-stimulated insulin secretion by inducing inositol trisphosphate receptor (IP(3)R)-mediated calcium ion (Ca2+) release. Ankyrin-B binds to the IP(3)R and is enriched in pancreatic beta cells. We found that ankyrin-B-deficient islets displayed impaired potentiation of insulin secretion by the muscarinic agonist carbachol, blunted carbachol-mediated intracellular Ca2+ release, and reduced the abundance of IP3R. Ankyrin-B-haploinsufficient mice exhibited hyperglycemia after oral ingestion but not after intraperitoneal injection of glucose, consistent with impaired parasympathetic potentiation of glucose-stimulated insulin secretion. The R1788W mutation of ankyrin-B impaired its function in pancreatic islets and is associated with type 2 diabetes in Caucasians and Hispanics. Thus, defective glycemic regulation through loss of ankyrin-B-dependent stabilization of IP3R is a potential risk factor for type 2 diabetes.
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Affiliation(s)
- Jane A Healy
- 1Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC 27710, USA
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21
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Relationships between early postnatal growth and metabolic function of 16-month-old female offspring born to ewes exposed to different environments during pregnancy. J Dev Orig Health Dis 2009; 1:50-9. [DOI: 10.1017/s2040174409990201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
It was hypothesized that exposure of the fetus to adverse conditions in utero due to either maternal constraint or nutrition may result in developmental adaptations altering metabolism and postnatal growth of the offspring. Heavy (H) and light (L) Romney dams (G0) were allocated to ad libitum (A) or maintenance (M) nutritional regimens, from day 21–day 140 of pregnancy. Female twin-born offspring (G1) born to the dams in the four treatment groups will be referred to as HA-ewes, LA-ewes, HM-ewes and LM-ewes. At 16 months of age, offspring were catheterized and given intravenous insulin tolerance test (ITT), glucose tolerance test (GTT) and epinephrine tolerance test challenges to assess their glucose and fat metabolism in relation to their birth weight and postnatal growth. In HA-ewes, the regression coefficients of growth rates prior to puberty on insulin and glucose curves in response to GTT (InsAUCGTT) and ITT (GluAUCITT), respectively, were different from 0 (P < 0.05) and were different from the regression coefficients of HM-ewes. This may indicate that HA-ewes may have showed puberty-related insulin resistance at 16 months of age with increasing growth rates prior to puberty compared to HM- or LM-ewes. In HM-ewes, the regression coefficients of growth rates after puberty on InsAUCGTT and GluAUCITT were different from 0 (P < 0.05) and were different from those of HA-ewes. These results may indicate that offspring born to heavy dams fed maintenance during pregnancy and with greater postnatal growth rates after puberty could develop glucose intolerance and insulin resistance in later life.
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Lotz T, Göltenbott U, Chase JG, Docherty P, Hann CE. A minimal C-peptide sampling method to capture peak and total prehepatic insulin secretion in model-based experimental insulin sensitivity studies. J Diabetes Sci Technol 2009; 3:875-86. [PMID: 20144337 PMCID: PMC2769977 DOI: 10.1177/193229680900300435] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AIMS AND BACKGROUND Model-based insulin sensitivity testing via the intravenous glucose tolerance test (IVGTT) or similar is clinically very intensive due to the need for frequent sampling to accurately capture the dynamics of insulin secretion and clearance. The goal of this study was to significantly reduce the number of samples required in intravenous glucose tolerance test protocols to accurately identify C-peptide and insulin secretion characteristics. METHODS Frequently sampled IVGTT data from 12 subjects [5 normal glucose-tolerant (NGT) and 7 type 2 diabetes mellitus (T2DM)] were analyzed to calculate insulin and C-peptide secretion using a well-accepted C-peptide model. Samples were reduced in a series of steps based on the critical IVGTT profile points required for the accurate estimation of C-peptide secretion. The full data set of 23 measurements was reduced to sets with six or four measurements. The peak secretion rate and total secreted C-peptide during 10 and 20 minutes postglucose input and during the total test time were calculated. Results were compared to those from the full data set using the Wilcoxon rank sum to assess any differences. RESULTS In each case, the calculated secretion metrics were largely unchanged, within expected assay variation, and not significantly different from results obtained using the full 23 measurement data set (P < 0.05). CONCLUSIONS Peak and total C-peptide and insulin secretory characteristics can be estimated accurately in an IVGTT from as few as four systematically chosen samples, providing an opportunity to minimize sampling, cost, and burden.
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Affiliation(s)
- Thomas Lotz
- Department of Mechanical Engineering, Centre for Bio-Engineering, University of Canterbury, Christchurch, New Zealand
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Xie L, Hoffman RP, Veng-Pedersen P. Noncompartmental pharmacokinetics analysis of glucose-stimulated insulin response in African-American and Caucasian youths. Biopharm Drug Dispos 2009; 30:117-25. [PMID: 19288584 DOI: 10.1002/bdd.652] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The objective of this study was to examine the differences in glucose and insulin responses between African-American and Caucasian youths and to determine the associations of between-group differences with sex, body mass index (BMI) and pubertal status using a noncompartmental pharmacokinetic approach. Sixteen African-American and 22 Caucasian healthy adolescents were tested using the frequently sampled intravenous glucose tolerance test. Longitudinal t-tests across each observation revealed that (1) African-American youths have higher insulin concentrations between 4 to 19 min; (2) insulin levels remained similar as subjects were grouped according to sex and pubertal status; (3) for glucose, the only difference was found as it approached steady-state basal level (>100 min) between groups with different BMIs. Linear regression showed that insulin concentrations between 4 to 19 min are associated with BMI in Caucasians. African-American youths were found to have higher insulin responses after glucose stimulation and the insulin concentrations were more related to BMI in Caucasians compared with African-Americans. BMI also has a significant effect on the glucose steady state basal level. The acute insulin response to glucose (AIR(g)) extended to 20 min resulted in a more significant racial difference (p<0.0006) compared with the calculation done over 10 min suggested in the past (p<0.001).
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Affiliation(s)
- Lanyi Xie
- Department of Pharmaceutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA
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24
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Todd SE, Oliver MH, Jaquiery AL, Bloomfield FH, Harding JE. Periconceptional undernutrition of ewes impairs glucose tolerance in their adult offspring. Pediatr Res 2009; 65:409-13. [PMID: 19092719 DOI: 10.1203/pdr.0b013e3181975efa] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Maternal undernutrition throughout pregnancy can have long-term effects on the health of adult offspring. Undernutrition around the time of conception alters growth, metabolism, and endocrinology of the sheep fetus, but the impact on offspring after birth is largely unknown. We determined the effect of maternal periconceptional undernutrition in sheep on glucose tolerance in the offspring before and after puberty. Undernourished (UN) ewes were fed individually to maintain weight loss of 10-15% bodyweight from 61 d before until 30 d after mating. Offspring (24 UN, 30 control) underwent an i.v. glucose tolerance test at 4 and 10 mo of age. Glucose tolerance was similar in both groups at 4 mo. Insulin area under the curve increased by 33% between 4 and 10 mo (101 +/- 8 versus 154 +/- 12 ng x min x mL(-1), p < 0.0001). At 10 mo, UN offspring had a 10% greater glucose area under the curve than controls (809 +/- 22 versus 712 +/- 20 mM x min, p < 0.01), a reduced first phase insulin response (p = 0.003) which was particularly apparent in females and in singletons, and a decreased insulin:glucose ratio (p = 0.01). We conclude that maternal undernutrition around the time of conception results in impaired glucose tolerance in postpubertal offspring.
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Affiliation(s)
- Sarah E Todd
- Liggins Institute, University of Auckland, Private Bag 92019, Auckland 1023, New Zealand
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Guillausseau PJ, Meas T, Virally M, Laloi-Michelin M, Médeau V, Kevorkian JP. Abnormalities in insulin secretion in type 2 diabetes mellitus. DIABETES & METABOLISM 2008; 34 Suppl 2:S43-8. [PMID: 18640585 DOI: 10.1016/s1262-3636(08)73394-9] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Type 2 diabetes mellitus is a multifactorial disease, due to decreased glucose peripheral uptake, and increased hepatic glucose production, due to reduced both insulin secretion and insulin sensitivity. Multiple insulin secretory defects are present, including absence of pulsatility, loss of early phase of insulin secretion after glucose, decreased basal and stimulated plasma insulin concentrations, excess in prohormone secretion, and progressive decrease in insulin secretory capacity with time. beta-cell dysfunction is genetically determined and appears early in the course of the disease. The interplay between insulin secretory defect and insulin resistance is now better understood. In subjects with normal beta-cell function, increase in insulin is compensated by an increase in insulin secretion and plasma glucose levels remain normal. In subjects genetically predisposed to type 2 diabetes, failure of beta-cell to compensate leads to a progressive elevation in plasma glucose levels, then to overt diabetes. When permanent hyperglycaemia is present, progressive severe insulin secretory failure with time ensues, due to glucotoxicity and lipotoxicity, and oxidative stress. A marked reduction in beta-cell mass at post-mortem examination of pancreas of patients with type 2 diabetes has been reported, with an increase in beta-cell apoptosis non-compensated by neogenesis.
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Affiliation(s)
- P-J Guillausseau
- AP-HP, Department of Internal Medicine B, Hôpital Lariboisière, 2, rue Ambroise Raré, 75010, Paris, France.
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Li J, Tian H, Li Q, Wang N, Wu T, Liu Y, Ni Z, Yu H, Liang J, Luo R, Li Y, Huang L. Improvement of insulin sensitivity and beta-cell function by nateglinide and repaglinide in type 2 diabetic patients - a randomized controlled double-blind and double-dummy multicentre clinical trial. Diabetes Obes Metab 2007; 9:558-65. [PMID: 17587398 DOI: 10.1111/j.1463-1326.2006.00638.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM To evaluate the efficacy of nateglinide vs. repaglinide in blood glucose (BG) control and the effect on insulin resistance and beta-Cell function in patients with type 2 diabetes. METHODS A randomized controlled double-blind and double-dummy multicentre clinical trial was conducted. A total of 230 Chinese patients with type 2 diabetes were enrolled in five clinical centres. The patients were divided randomly into group A [repaglinide 1.0 mg three times daily (t.i.d.), n = 115] or group B (nateglinide 90 mg t.i.d., n = 115). At baseline and end of the 12-week clinical trial, standard mixed meal tolerance tests were performed. RESULTS A total of 223 patients (96.9%) completed the trial. There was no significant difference between repaglinide and nateglinide groups in the effects of reducing fasting blood glucose (FBG), 30-, 60- and 120-min BG during 12 weeks (p > 0.05). At week 12, no significant difference was shown between the two groups in BG or haemoglobin A(1c) (HbA(1c)) (p > 0.05). However, the effect on HbA(1c) in repaglinide group was stronger than that in nateglinide group (p < 0.05). After 12-week treatment, area under the curve (AUC) of BG decreased (p < 0.05), and AUC of insulin and C-peptide (CP) increased in both groups (p < 0.05). The effects of nateglinide on AUC of BG, insulin and CP were similar to that of repaglinide (p > 0.05). There was no significant difference between the two groups in AUC of BG, insulin or CP in week 12 (p > 0.05). Furthermore, homeostasis model assessment of insulin resistance (HOMA-IR) and beta-cell function indexes measured by HOMA-beta, DeltaI(30)/DeltaG(30) and (DeltaI(30)/DeltaG(30))/HOMA-IR were improved significantly in both groups during 12 weeks (p < 0.05). The effects of improving HOMA-IR and beta-cell function indexes in nateglinide group were comparable with that of repaglinide group (p > 0.05). CONCLUSIONS The efficacy of repaglinide and nateglinide in FBG, postprandial glucose excursion and early-phase insulin secretion is similar. But the effect of repaglinide 1.0 mg t.i.d. on HbA(1c) is stronger than that of nateglinide 90 mg t.i.d.. This trial had shown that nateglinide and repaglinide could comparably improve insulin sensitivity and beta-cell function.
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Affiliation(s)
- J Li
- Department of Endocrinology, State Key Lab of Biotherapy, West China Hospital of Sichuan University, Chengdu, China
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Chailurkit LO, Jongjaroenprasert W, Chanprasertyothin S, Ongphiphadhanakul B. Insulin and C-peptide levels, pancreatic beta cell function, and insulin resistance across glucose tolerance status in Thais. J Clin Lab Anal 2007; 21:85-90. [PMID: 17385686 PMCID: PMC6649081 DOI: 10.1002/jcla.20138] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Impaired pancreatic beta cell function and insulin sensitivity are fundamental factors in the pathogenesis of type 2 diabetes; however, the predominant defect appears differ among ethnic groups. We conducted a cross-sectional study to evaluate the contribution of impaired beta cell function and insulin sensitivity at different stages of the deterioration of glucose tolerance in Thais. The study involved 420 urban Thais of both sexes, 43-84 years old. A 75-g oral glucose tolerance test was performed on all of the subjects. Indices of insulin resistance and beta cell function were calculated with the use of a homeostasis model assessment. The subjects were classified as having normal glucose tolerance (NGT), isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT), combined IFG and IGT, or type 2 diabetes mellitus according to the American Diabetes Association (ADA) criteria. There were no differences between groups with regard to gender and age. The percentage of obesity was significantly greatest in the diabetic group. Fasting serum insulin and C-peptide levels progressively increased from the NGT to the diabetic subjects. Serum C-peptide was more strongly associated with newly diagnosed diabetes than insulin, and was an independent factor associated with newly diagnosed diabetic subjects. The insulin resistance index progressively increased when the glucose tolerance stage changed from NGT through diabetic subjects. Beta cell function did not change significantly in any other group compared to the NGT group. An increase in fasting serum C-peptide may be a risk factor for type 2 diabetes. Obesity and insulin resistance are the predominant features in the deterioration of glucose tolerance in Thais.
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Affiliation(s)
- La-or Chailurkit
- Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
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Yang CC, Lin JD, Kuo KL, Wu CZ, Li JC, Hung YJ, Wang TF, Lee CH, Kuo SW, Pei D. The comparison of second phase insulin secretion in patients treated with repaglinide or gliclazide. Diabetes Metab Syndr 2007. [DOI: 10.1016/j.dsx.2006.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ritzel RA, Veldhuis JD, Butler PC. The mass, but not the frequency, of insulin secretory bursts in isolated human islets is entrained by oscillatory glucose exposure. Am J Physiol Endocrinol Metab 2006; 290:E750-6. [PMID: 16278244 DOI: 10.1152/ajpendo.00381.2005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Insulin is secreted in discrete insulin secretory bursts. Regulation of insulin release is accomplished almost exclusively by modulation of insulin pulse mass, whereas the insulin pulse interval remains stable at approximately 4 min. It has been reported that in vivo insulin pulses can be entrained to a pulse interval of approximately 10 min by infused glucose oscillations. If oscillations in glucose concentration play an important role in the regulation of pulsatile insulin secretion, abnormal or absent glucose oscillations, which have been described in type 2 diabetes, might contribute to the defective insulin secretion. Using perifused human islets exposed to oscillatory vs. constant glucose, we questioned 1) whether the interval of insulin pulses released by human islets is entrained to infused glucose oscillations and 2) whether the exposure of islets to oscillating vs. constant glucose confers an increased signal for insulin secretion. We report that oscillatory glucose exposure does not entrain insulin pulse frequency, but it amplifies the mass of insulin secretory bursts that coincide with glucose oscillations (P < 0.001). Dose-response analyses showed that the mode of glucose drive does not influence total insulin secretion (P = not significant). The apparent entrainment of pulsatile insulin to infused glucose oscillations in nondiabetic humans in vivo might reflect the amplification of underlying insulin secretory bursts that are detected as entrained pulses at the peripheral sampling site, but without changes in the underlying pacemaker activity.
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Affiliation(s)
- R A Ritzel
- Larry Hillblom Islet Research Center, University of California, Los Angeles David Geffen School of Medicine, Los Angeles, California 90095-7073, USA
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Pei D, Hsiao CF, Hung YJ, Hsieh CH, Fang SC, Lian WC, Hsu WL, Fu CC, Chen HD, Kuo SW. The insulin sensitivity, glucose sensitivity, and acute insulin response to glucose load in adolescent type 2 diabetes in Taiwanese. Diabetes Metab Res Rev 2006; 22:26-33. [PMID: 15880384 DOI: 10.1002/dmrr.522] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Insulin sensitivity (SI), glucose sensitivity (SG), acute insulin response to glucose load (AIR), and obesity in adolescent type 2 diabetes patients (young diabetes, YDM) in Taiwan were studied. METHODS Forty patients diagnosed at <22 years of age were enrolled and divided into non-obese (NOYDM, BMI < 27 kg/m(2)) and obese groups (OBYDM BMI > 27 kg/m(2)). Adult-onset type 2 diabetes patients (ADM) >40 years old (n = 41) and nondiabetic young adults (N) (n = 23) served as controls. Fasting plasma lipids, insulin, and glucose were measured. Homeostasis model assessment was calculated to estimate insulin sensitivity and beta-cell function. A frequent-sampled intravenous glucose tolerance test was performed to evaluate SI, SG, and AIR. RESULTS SI and AIR were significantly lower in YDM and ADM than in N (0.92 +/- 0.13, 0.8 +/- 0.15 and 3.24 +/- 0.47 x 10(-4)/U/mL for SI; 40.3 +/- 20.3, 107.3 +/- 50.2, 1208 +/- 306.3 uU/min for AIR). SG of YDM and ADM were lower compared with N (0.014 +/- 0.00138, 0.0292 +/- 0.0058 vs 0.034 +/- 0.0086 min(-1) respectively). No difference was noted between YDM and ADM. SI and SG were not different in NOYDM and OBYDM. AIR was higher in OBYDM (83.6 +/- 34.3 vs -7.6 +/- 13.66 uU/min). CONCLUSIONS YDM had defects in SI, SG, and AIR compared to N, which was similar to the pathophysiology of ADM. The results imply that YDM may be either a different subtype of diabetes or the same type of diabetes as ADM, with severe defects associated with earlier age of onset. OBYDM had higher AIR than NOYDM.
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Affiliation(s)
- Dee Pei
- Department of Internal Medicine, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, ROC
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Kang HW, Kim DJ, Lee MS, Kim KW, Lee MK. Pathophysiologic heterogeneity in the development of type 2 diabetes mellitus in Korean subjects. Diabetes Res Clin Pract 2005; 69:180-7. [PMID: 16005368 DOI: 10.1016/j.diabres.2004.12.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2004] [Revised: 12/06/2004] [Accepted: 12/12/2004] [Indexed: 11/16/2022]
Abstract
OBJECTIVE To investigate the clinical characteristics and predisposing metabolic abnormalities in the development of glucose intolerance and diabetes mellitus in obese and non-obese Korean subjects. METHODS Four hundred Korean subjects were classified into five groups according to degree of glucose tolerance by OGTT: NGT, IGT alone, IFG alone, IFG+IGT, and DM. The groups were also subdivided into obese and non-obese group according to body mass index. Insulin resistance was assessed by using homeostasis model assessment of insulin resistance (HOMA-R), and insulinogenic index was used as an index of early-phase insulin secretion. RESULTS Impaired early-phase insulin secretion was seen in non-obese IGT alone, IFG alone, and IFG+IGT, though more profound secretory defects were noted in IFG+IGT and DM. No significant difference were found in HOMA-R among non-obese IGT alone, IFG alone, or IFG+IGT, or in terms of early-phase insulin secretion in obese IGT alone, IFG alone, or IFG+IGT. However, the magnitude of insulin resistance differed in the obese group, IFG+IGT and DM being more insulin resistant than IGT alone or IFG alone. CONCLUSIONS These results suggest that the predisposing metabolic abnormality in non-obese subjects with IGT alone or IFG alone and in progression to IFG+IGT might be deterioration of early phase insulin secretion, whereas insulin resistance might be the major contributory factor in obese subjects. The predisposing metabolic abnormality leading to diabetes in both obese and non-obese groups was deterioration of early-phase insulin secretion.
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Affiliation(s)
- Hahn Wook Kang
- Department of Internal Medicine, Hallym Hospital, 900-4 Jakjen-Dong, Gyeyang-Ku, Inchon, Republic of Korea.
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Affiliation(s)
- M J Davies
- Department of Diabetes and Endocrinology, University Hospitals of Leicester NHS Trust, Leicester Royal Infirmary, Leicester, UK
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Osei K, Rhinesmith S, Gaillard T, Schuster D. Impaired insulin sensitivity, insulin secretion, and glucose effectiveness predict future development of impaired glucose tolerance and type 2 diabetes in pre-diabetic African Americans: implications for primary diabetes prevention. Diabetes Care 2004; 27:1439-46. [PMID: 15161801 DOI: 10.2337/diacare.27.6.1439] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE We examined the determinants of impaired glucose tolerance (IGT) and type 2 diabetes in first-degree relatives of African-American type 2 diabetic patients over 5-8 years (median 6). RESEARCH DESIGN AND METHODS A total of 81 healthy subjects (age 41.5 +/- 4.8 years; BMI 31.3 +/- 3.6 kg/m(2)) participated in the study. Each subject underwent an oral glucose tolerance test (OGTT) and a frequently sampled intravenous glucose tolerance test at baseline. Insulin sensitivity index (S(i)) and glucose effectiveness index (S(g)) were determined by the minimal model method. Homeostasis model assessment (HOMA) was used to estimate insulin resistance (HOMA-IR) and beta-cell function (HOMA-%B). A total of 18 subjects progressed to either IGT or type 2 diabetes (progressors), whereas 19 subjects maintained normal glucose tolerance (nonprogressors). RESULTS Comparing the progressors and nonprogressors, mean fasting serum glucose levels (95 +/- 8 vs. 80 +/- 14 mg/dl, P < 0.01) and 2-h serum glucose levels (149 +/- 27 vs. 100 +/- 60 mg/dl, P < 0.01) as well as 2-h serum insulin levels (117 +/- 81 vs. 72 +/- 87 microU/ml, P < 0.01) during OGTT were higher at baseline. Mean acute first-phase insulin secretion (205 +/- 217 vs. 305 +/- 230 microU/ml), HOMA-%B (148 +/- 60 vs. 346 +/- 372, P < 01), S(i) (1.61 +/- 1.13 vs. 2.48 +/- 1.25 x 10(-4). min(-1) [microU/ml](-1)), and S(g) (1.48 +/- 0.61 vs. 2.30 +/- 0.97 x 10(-2). min(-1)) were lower in the progressors than in the nonprogressors at baseline. Mean HOMA-IR (3.31 +/- 1.64 vs. 2.36 +/- 1.64) was significantly greater in the progressors than the nonprogressors. At the time of diagnosis of glucose intolerance (IGT + diabetes), HOMA-%B (101 +/- 48 vs. 148 +/- 60, P < 0.001) and HOMA-IR (5.44 +/- 2.55 vs. 3.31 +/- 1.64, P < 0.003) deteriorated in the progressors versus baseline. CONCLUSIONS We conclude that nondiabetic, first-degree relatives of African-American type 2 diabetic patients who progressed to IGT and type 2 diabetes manifest triple defects (decreased insulin secretion, insulin action, and glucose effectiveness) that antecede the disease.
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Affiliation(s)
- Kwame Osei
- Ohio State University College of Medicine and Public Health, 491 McCampbell Hall, Columbus, OH 43210, USA.
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Mensink M, Feskens EJM, Kruijshoop M, de Bruin TWA, Saris WHM, Blaak EE. Subscapular skinfold thickness distinguishes between transient and persistent impaired glucose tolerance: Study on Lifestyle-Intervention and Impaired Glucose Tolerance Maastricht (SLIM). Diabet Med 2003; 20:552-7. [PMID: 12823236 DOI: 10.1046/j.1464-5491.2003.00962.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS To assess whether adding anthropometric measurements to an oral glucose tolerance test (OGTT) can help to distinguish between transient and persistent impaired glucose tolerance (IGT). METHODS From the SLIM project (Study on Lifestyle-Intervention and IGT Maastricht), a study designed to evaluate whether diet and physical activity intervention can improve glucose tolerance in subjects at risk for diabetes, 108 subjects with IGT underwent a repeated OGTT 2-4 months after the initial OGTT. Following the second test, subjects were classified as transient IGT, or persistent IGT. Anthropometric measurements, including body mass index, waist and hip circumference, sagittal and transverse abdominal diameters and skinfold thickness measurements, were done during the second OGTT. RESULTS Persistent IGT was diagnosed in 47 subjects (44%), transient IGT in 40 (37%), impaired fasting glucose in eight subjects (7%), and diabetes in 13 cases (12%). Two-hour blood glucose levels at the initial OGTT and subscapular skinfold thickness were significantly higher in subjects with persistent IGT (2-h blood glucose 9.8+/-0.1 mmol/l vs. 10.2+/-0.1 mmol/l for transient IGT and persistent IGT, respectively; subscapular skinfold thickness 25.4+/-1.4 mm vs. 29.8+/-1.2 mm for transient IGT and persistent IGT, respectively). After adjustment for age, sex and family history of diabetes mellitus, logistic regression indicated that 2-h blood glucose level during the initial OGTT represented the strongest predictor of persistent IGT (P<0.02), followed by subscapular skinfold thickness (P<0.05). After adjustment for 2-h blood glucose levels during the first OGTT, subscapular skinfold thickness remained significantly associated with persistent IGT (odds ratio 1.84; P<0.05). CONCLUSIONS In addition to the 2-h blood glucose level, subscapular skinfold thickness was the best predictor of persistent IGT, suggesting that adding simple anthropometric measures to oral glucose tolerance testing may improve the distinction between persistent and transient glucose intolerance.
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Affiliation(s)
- M Mensink
- Department of Human Biology, Nutrition and Toxicology Research Institute (NUTRIM), Maastricht University, Maastricht, The Netherlands.
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Ferreira F, Filiputti E, Arantes VC, Stoppiglia LF, Araújo EP, Delghingaro-Augusto V, Latorraca MQ, Toyama MH, Boschero AC, Carneiro EM. Decreased cholinergic stimulation of insulin secretion by islets from rats fed a low protein diet is associated with reduced protein kinase calpha expression. J Nutr 2003; 133:695-9. [PMID: 12612139 DOI: 10.1093/jn/133.3.695] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Undernutrition has been shown to affect the autonomic nervous system, leading to permanent alterations in insulin secretion. To understand these interactions better, we investigated the effects of carbamylcholine (CCh) and phorbol 12-myristate 13-acetate (PMA) on insulin secretion in pancreatic islets from rats fed a normal (17%; NP) or low (6%; LP) protein diet for 8 wk. Isolated islets were incubated for 1 h in Krebs-bicarbonate solution containing 8.3 mmol glucose/L, with or without PMA (400 nmol/L) and CCh. Increasing concentrations of CCh (0.1-1000 micro mol/L) dose dependently increased insulin secretion by islets from both groups of rats. However, insulin secretion by islets from rats fed the NP diet was significantly higher than that of rats fed the LP diet, and the dose-response curve to CCh was shifted to the right in islets from rats fed LP with a 50% effective concentration (EC(50)) of 2.15 +/- 0.7 and 4.64 +/- 0.1 micro mol CCh/L in islets of rats fed NP and LP diets, respectively (P < 0.05). PMA-induced insulin secretion was higher in islets of rats fed NP compared with those fed LP. Western blotting revealed that the protein kinase (PK)Calpha and phospholipase (PL)Cbeta(1) contents of islets of rats fed LP were 30% lower than those of islets of rats fed NP (P < 0.05). In addition, PKCalpha mRNA expression was reduced by 50% in islets from rats fed LP. In conclusion, a reduced expression of PKCalpha and PLCbeta(1) may be involved in the decreased insulin secretion by islets from LP rats after stimulation with CCh and PMA.
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Affiliation(s)
- Fabiano Ferreira
- Departamento de Fisiologia e Biofísica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), SP, Brasil
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Abstract
After a short description of normal glucose homeostasis, recent findings in relation to insulin release in three groups with a high risk of future development of type 2 diabetes are described. Hyperglycemic clamps in subjects with impaired glucose tolerance (IGT) clearly indicate that pancreatic beta cell function is decreased, in addition to the decreased insulin sensitivity. In women with former gestational diabetes mellitus (GDM), insulin release is also lower than in controls. In Caucasian first-degree relatives (FDRs) with normal glucose tolerance, various studies have shown that beta cell function is lower than in controls, while on the average insulin sensitivity is normal. This implies that beta cell function is disturbed earlier in subjects at risk of developing diabetes than is often appreciated. In the near future, the genetic studies currently underway will presumably unravel the pathogenesis of disturbances both in insulin secretion and in insulin action, in type 2 diabetes mellitus.
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Affiliation(s)
- Timon W van Haeften
- Department of Internal Medicine-G 02.228, University Medical Center Utrecht, PO Box 85500, N 3508 GA Utrecht, The Netherlands.
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Cozma LS, Luzio SD, Dunseath GJ, Langendorg KW, Pieber T, Owens DR. Comparison of the effects of three insulinotropic drugs on plasma insulin levels after a standard meal. Diabetes Care 2002; 25:1271-6. [PMID: 12145220 DOI: 10.2337/diacare.25.8.1271] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To compare the effects of repaglinide, glipizide, and glibenclamide on insulin secretion and postprandial glucose after a single standard 500-kcal test meal. RESEARCH DESIGN AND METHODS A total of 12 type 2 diabetic patients with early diabetes (mean HbA(1c) of 6.1%) and 12 matched control subjects were enrolled in this randomized, double-blind, crossover trial. Subjects received placebo, 2 mg repaglinide, 5 mg glipizide, and 5 mg glibenclamide in a random fashion during the trial. Administration of each drug was followed by a single standard 500-kcal test meal. A washout period of 7-12 days existed between the four study visits. RESULTS All three drugs were equally effective on the total prandial insulin secretion (area under the curve [AUC] -15 to 240 min). However, clear differences were noted in the early insulin secretion (AUC -15 to 30 min); both repaglinide and glipizide increased secretion in nondiabetic subjects by approximately 61 and 34%, respectively, compared with placebo. In the diabetic patients, the difference versus placebo was 37 and 47%, respectively. The difference between glipizide and glibenclamide reached significance in both groups of subjects, whereas repaglinide was more effective than glibenclamide only in the healthy nondiabetic subject group. All three drugs were effective in decreasing total glucose AUC in the nondiabetic and diabetic population. In the nondiabetic subjects, however, repaglinide was significantly more effective than glibenclamide. The differences disappeared in the diabetic subjects, probably as a result of increased prevalence of insulin resistance in this group. CONCLUSIONS Repaglinide and glipizide but not glibenclamide significantly enhanced the early insulin secretion in both nondiabetic and diabetic subjects with preserved beta-cell function after a single standard meal.
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Affiliation(s)
- Lawrence S Cozma
- Diabetes Research Unit, University Hospital of Wales, College of Medicine, South Glamorgan, Wales, Bagsvaerd, Denmark.
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Toschi E, Camastra S, Sironi AM, Masoni A, Gastaldelli A, Mari A, Ferrannini E, Natali A. Effect of acute hyperglycemia on insulin secretion in humans. Diabetes 2002; 51 Suppl 1:S130-3. [PMID: 11815471 DOI: 10.2337/diabetes.51.2007.s130] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
First-phase insulin response to intravenous glucose is impaired both in type 2 diabetic patients and in subjects at risk for the disease. Hyperglycemia can modify beta-cell response by either inhibiting or potentiating both first- and second-phase insulin release. In normal subjects, the effect of acute hyperglycemia on insulin secretion is controversial. We measured (in 13 healthy volunteers) insulin secretion (by deconvolution of plasma C-peptide concentrations) during three consecutive 30-min hyperglycemic steps (2.8, 2.8, and 5.6 mmol/l), followed by an intravenous arginine bolus. First-phase insulin secretion in response to the first hyperglycemic step (456 +/- 83 pmol.min(-1).m(-2)) was significantly larger than that in response to the second step (311 +/- 37 pmol.min(-1).m(-2), P < 0.01); the subsequent increase in glycemia failed to stimulate first-phase secretion any further (377 +/- 60 pmol.min(-1).m(-2), NS vs. the previous value). This inhibition was also evident when insulin release rates were corrected for the respective increments (absolute or percentage) in plasma glucose levels and was not due to beta-cell exhaustion because the arginine bolus still elicited a large peak of insulin secretion (4,790 +/- 2,330 pmol.min(-1).m(-2)). In contrast, second-phase insulin secretion was related to the prevailing glucose levels across the three hyperglycemic steps in a direct quasilinear manner. We conclude that first-phase insulin secretion is inhibited by short-term modest hyperglycemia, whereas the second-phase insulin secretion increases linearly with hyperglycemia.
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Affiliation(s)
- Elena Toschi
- Metabolism Unit, CNR Institute of Clinical Physiology, University of Pisa, Via Savi 8, 56126 Pisa, Italy
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Abstract
Type 2 diabetes is a heterogeneous disorder due to prevalent insulin resistance associated with deficient insulin secretion or to a prevalent defect of insulin secretion associated with impaired insulin action. The definition is supported by the high frequency at which insulin resistance can be demonstrated in type 2 diabetic patients. Nonetheless, insulin resistance is not a sufficient mechanism to cause diabetes. Impaired beta-cell function is a necessary defect in all conditions of impaired glucose regulation; however, it manifests itself in a different manner in fasting and glucose-stimulated conditions. In the fasting state, the basal insulin secretory rate increases as a function of the progressive decline in insulin action. As such, the fasting plasma insulin concentration is often taken as a marker for insulin sensitivity. After glucose challenge, a specific alteration of acute insulin release is an early and progressive defect. The latter might represent an intrinsic defect, but its continuous decline is affected by glucotoxicity and lipotoxicity. To understand the impact of beta-cell dysfunction in type 2 diabetes on metabolic homeostasis, it is useful to consider the different phases of insulin secretion separately. Insulin secretion can be divided into basal (postabsorptive) and stimulated (postprandial) states. The former prevails during the interprandial phases and plays a major role during the overnight fast; the latter regulates glucose metabolism when carbohydrate is abundant and must be disposed of. Data in animals and humans support a crucial physiological role of first-phase insulin secretion in postprandial glucose homeostasis. This effect is primarily achieved in the liver, allowing prompt inhibition of endogenous glucose production and limiting the postprandial rise in plasma glucose level. In type 2 diabetes, loss of the early surge of insulin release is an early and quite common defect that may have a pathogenetic role in the development of postprandial hyperglycemia, possibly requiring specific therapeutic intervention.
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Affiliation(s)
- Stefano Del Prato
- Department of Endocrinology and Metabolism, Section of Diabetes, University of Pisa, Pisa, Italy.
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40
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Abstract
Existing oral insulin secretagogues, sulphonylureas, are associated with hyperinsulinaemia, risk of hypoglycaemia and weight gain. Furthermore, they are not able to offer durable glycaemic control in patents with type 2 diabetes and are associated with progressive decline of beta-cell function. New insulin secretagogues offer an exciting opportunity. Repaglinide, the first prandial glucose regulator, now has convincing data that, compared to sulphonylurea use, it has a lower risk of hypoglycaemia. When used in a flexible dosing regime in a large cohort of patients, it is associated with better glycaemic control, a reduction in HbA1c, weight loss and improved quality of life compared to sulphonylureas. Early data shows the possibility of an effective combination with night time isophane insulin with significant falls in HbA1c and lower doses of insulin required. Nateglinide is an amino acid derivative. It again acts directly on the pancreatic beta-cell. Because of its very short duration of action, and the fact that it appears to secrete insulin in a glucose-dependent manner, it appears to secrete insulin in the closest way to that seen in a person without diabetes. Early data, both in monotherapy and in combination with metformin, show that it is an effective agent in terms of lowering HbA1c, has a low risk of hypoglycaemia and potentially less risk of significant weight gain. These characteristics mean that it may be the ideal agent to be used very early in the disease process, or even in subjects with impaired glucose tolerance, in whom early-phase insulin response is already lost. However these concepts, at the present time, are unproven.
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Affiliation(s)
- Melanie J Davies
- Department of Diabetes, Endocrinology and Cardiovascular Medicine, University Hospital of Leicester, UK.
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Abstract
The role of postprandial hyperglycemia (PPHG) in diabetes mellitus is being increasingly recognized. It is known that PPHG contributes to the increased risk of both micro- and macrovascular complications in patients with diabetes mellitus. This review looks at the clinical significance of PPHG and the currently available therapeutic modalities. The causes of PPHG are influenced by many factors which include a rapid flux of glucose from the gut, impaired insulin release, endogenous glucose production by the liver and peripheral insulin resistance. Knowledge of the pathophysiology of PPHG is essential when adopting treatment options to tackle the problem. Although most oral antihyperglycemic agents and insulins lower both fasting and postprandial blood glucose levels, drugs are now available which specifically act to control PPHG. These drugs may be classified based on the site of their action. alpha-Glucosidase inhibitors like acarbose and miglitol attenuate the rate of absorption of sucrose by acting on the luminal enzymes. Adverse effects of these agents are predominantly gastrointestinal. Newer insulin secretagogues have been developed which attempt to mimic the physiological release of insulin and thus ameliorate PPHG. These include third generation sulfonylureas like glimepiride and nonsulfonylurea secretagogues like repaglinide and nateglinide. Rapid-acting insulin analogs, the amino acid sequences of which have been altered such that they have a faster onset of action, help to specifically target PPHG. Pre-mixed formulations of the analogs have also been developed. Finally, drugs under development which hold promise in the management of patients with PPHG include pramlintide, an amylin analog, and glucagon-like peptide-1 and its analogs.
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Affiliation(s)
- Rajasekaran Sudhir
- MV Diabetes Specialities Centre and Madras Diabetes Research Foundation, Chennai, India
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42
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Hicks D. Recent developments in the management of type 2 diabetes. Br J Community Nurs 2001; 6:572, 574-5, 578-80. [PMID: 11832801 DOI: 10.12968/bjcn.2001.6.11.9458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Type 2 diabetes is a common, chronic disease, with a high risk of macrovascular and microvascular complications that lead to premature death and disability. The disease is managed largely in primary care and its rising prevalence will increase the workload of community nurses. The forthcoming Diabetes National Service Framework will aim to improve the standards of diabetic care, while scientific and technological developments offer new treatments that may also improve the outlook for patients. There is as yet no case for population screening for type 2 diabetes, but community nurses are ideally placed to carry out local screening initiatives based on consensus guidelines.
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Affiliation(s)
- D Hicks
- Michael White Centre for Diabetes and Endocrinology, Hull Royal Infirmary
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Costa B. [Watchwords for type-2 diabetes prevention in primary health care. The dilemma of the pre-diabetic status]. Aten Primaria 2001; 28:193-200. [PMID: 11459527 DOI: 10.1016/s0212-6567(01)78931-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- B Costa
- Grupos de investigación ITG y PREDIAP. Dirección de Atención Primaria Reus-Altebrat. Institut Català de la Salut. Reus, Tarragona
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Milicevic Z, Profozic V, Wyatt J, Ristic S, Woodworth JR, Seger M, Kaliterna D, Bates P, Metelko Z. Intramuscular injection of insulin lispro or soluble human insulin: pharmacokinetics and glucodynamics in Type 2 diabetes. Diabet Med 2001; 18:562-6. [PMID: 11553186 DOI: 10.1046/j.1464-5491.2001.00522.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM The aim of the study was to compare the pharmacokinetics and glucodynamics of insulin lispro and soluble human insulin following intramuscular (i.m.) injection in patients with Type 2 diabetes with secondary failure of sulphonylureas. METHODS Single 15-U i.m. doses of insulin lispro or soluble human insulin were administered to 16 patients in a two-way, randomized, crossover design. Glucodynamic and pharmacokinetic parameters were determined over 6 h after insulin injection using clamp techniques. RESULTS Insulin C(max) was significantly higher (971 +/- 217 vs. 659 +/- 141 pmol/l, P < 0.001) and T(max) was significantly shorter (46.9 +/- 27 vs. 94.7 +/- 50.1 min, P = 0.002) with insulin lispro. Glucose infusion rate (GIR) curves showed clear separation 20 min after injection and were significantly greater for insulin lispro during the 40-60, 60-80 and 80-100-minute time intervals. Total glucose infused was only approximately 5% larger with insulin lispro during the 6-h follow-up, due to lower insulinaemia at later time points. The glucose R(max) and TR(max) were not statistically different between insulin treatments. CONCLUSION This study shows that i.m. injection of insulin lispro is followed by its more rapid absorption, which results in stronger metabolic effect in the first 2 h when compared with soluble human insulin under the same test conditions. Diabet. Med. 18, 562-566 (2001)
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Affiliation(s)
- Z Milicevic
- University Clinic for Diabetes, Vuk Vrhovac Institute, Zagreb, Croatia.
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Affiliation(s)
- B Costa
- Grup per a L'Estudi de la Diabetis a Tarragona. Dirección de Atención Primaria Tarragona-Reus. Institut Català de la Salut. Unidad de Diabetes. Hospital de Móra d'Ebre (Grupo Sagessa). Tarragona.
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46
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Del Prato S, Tiengo A. The importance of first-phase insulin secretion: implications for the therapy of type 2 diabetes mellitus. Diabetes Metab Res Rev 2001; 17:164-74. [PMID: 11424229 DOI: 10.1002/dmrr.198] [Citation(s) in RCA: 150] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Type 2 diabetes is a heterogeneous disorder characterized by defects in insulin secretion and action. Insulin resistance is a key feature of type 2 diabetes. However, insulin resistance alone does not appear to be sufficient to cause diabetes. Longitudinal studies have shown that the development of overt hyperglycemia is associated with a decline in beta-cell secretion. In patients with impaired glucose tolerance or in the early stages of type 2 diabetes, first-phase insulin release is almost invariably lost despite the enhancement of second-phase secretion. Both animal and human studies support the critical physiologic role of the first-phase of insulin secretion in the maintenance of postmeal glucose homeostasis. This effect is primarily mediated at the level of the liver, allowing prompt inhibition of endogenous glucose production (EGP) and thereby restraining the mealtime rise in plasma glucose. In type 2 diabetes, the loss of the early surge of insulin release is a precocious and quite common defect that plays a pathogenic role in postmeal hyperglycemia and one that may require specific therapeutic intervention. This becomes even more apparent if the negative impact of prandial glucose spikes is taken into consideration. Epidemiological evidence exists to indicate that 2-h postload plasma glucose levels are strongly associated with all-cause and cardiovascular mortality relative risk. Indeed the acute elevation of plasma glucose concentration triggers an array of tissue responses that may contribute to the development of diabetic complications. Considering that type 2 diabetes begins with meal-related hyperglycemia in many patients, it becomes apparent that normalization of postmeal plasma glucose levels should be the target for rational therapy and the goal in the early stages of the disease. If a primary goal of diabetes therapy is control of postmeal glucose excursion, then the regulation of glucose absorption from the gut and entry into the circulation is an important mechanism to consider. The restoration of the rapid increase in plasma insulin concentration may be quite an efficient therapeutic approach.
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Affiliation(s)
- S Del Prato
- Cattedra di Malattie del Metabolismo, School of Medicine, University of Pisa, Italy.
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47
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Hanefeld M. Restoring early-phase insulin secretion - the new goal in type 2 diabetes management. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/pdi.176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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48
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Affiliation(s)
- T M Wallace
- Oxford Centre for Diabetes, Endocrinology and Metabolism, The Radcliffe Infirmary, UK
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49
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Davies MJ, Raymond NT, Day JL, Hales CN, Burden AC. Impaired glucose tolerance and fasting hyperglycaemia have different characteristics. Diabet Med 2000; 17:433-40. [PMID: 10975211 DOI: 10.1046/j.1464-5491.2000.00246.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS Use of the oral glucose tolerance test (OGTT) to define glucose intolerance in the general population may bias towards selection of those with insulin resistance. Beta cell function and insulin resistance markers were analysed in four groups: controls (n = 101); fasting hyperglycaemia (FH, n 45); impaired glucose tolerance; (IGT, n = 16) and those with features of both FH and IGT ('Both', n = 30). METHODS Subjects underwent an OGTT. Plasma glucose, fasting lipid profiles, fasting, 30 and 120 min insulin were measured and beta cell function (% B) and insulin sensitivity (% S) assessed by homeostatic model assessment (HOMA) RESULTS: The FH group compared to controls had a significantly lower % B. The IGT group compared to controls had features of insulin resistance (higher body mass index (BMI), systolic blood pressure and 2 h insulin concentration). Subjects with 'both' IGT and FH had features of insulin resistance (higher BMI, systolic and diastolic blood pressure and triglyceride concentration) as well as beta cell dysfunction with a lower % B and 30 min insulin-glucose ratio compared to controls. There was a preponderance of males in this group. In all, 192 subjects' 30-min insulin concentration and incremental insulin response showed only a significantly negative correlation with fasting glucose concentration. In a linear regression analysis, a low 30-min insulin-glucose ratio was only a significant factor in the fasting glucose model. Thus, higher fasting glucose concentrations appear to be associated with beta cell dysfunction. However, HbA1 only showed a significant correlation with 120-min glucose, not fasting glucose concentration. CONCLUSIONS In those with milder degrees of glucose intolerance, FH is associated with beta cell dysfunction and those with IGT and a relatively 'normal' fasting glucose have features of the insulin resistance syndrome.
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Affiliation(s)
- M J Davies
- Department of Diabetes and Endocrinology, Leicester Royal Infirmary, UK
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