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Trask L, Ward NA, Tarpey R, Beatty R, Wallace E, O'Dwyer J, Ronan W, Duffy GP, Dolan EB. Exploring therapy transport from implantable medical devices using experimentally informed computational methods. Biomater Sci 2024; 12:2899-2913. [PMID: 38683198 DOI: 10.1039/d4bm00107a] [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: 05/01/2024]
Abstract
Implantable medical devices that can facilitate therapy transport to localized sites are being developed for a number of diverse applications, including the treatment of diseases such as diabetes and cancer, and tissue regeneration after myocardial infraction. These implants can take the form of an encapsulation device which encases therapy in the form of drugs, proteins, cells, and bioactive agents, in semi-permeable membranes. Such implants have shown some success but the nature of these devices pose a barrier to the diffusion of vital factors, which is further exacerbated upon implantation due to the foreign body response (FBR). The FBR results in the formation of a dense hypo-permeable fibrous capsule around devices and is a leading cause of failure in many implantable technologies. One potential method for overcoming this diffusion barrier and enhancing therapy transport from the device is to incorporate local fluid flow. In this work, we used experimentally informed inputs to characterize the change in the fibrous capsule over time and quantified how this impacts therapy release from a device using computational methods. Insulin was used as a representative therapy as encapsulation devices for Type 1 diabetes are among the most-well characterised. We then explored how local fluid flow may be used to counteract these diffusion barriers, as well as how a more practical pulsatile flow regimen could be implemented to achieve similar results to continuous fluid flow. The generated model is a versatile tool toward informing future device design through its ability to capture the expected decrease in insulin release over time resulting from the FBR and investigate potential methods to overcome these effects.
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Affiliation(s)
- Lesley Trask
- Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
- Biomechanics Research Centre (BMEC), Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
| | - Niamh A Ward
- Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
- Biomechanics Research Centre (BMEC), Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
| | - Ruth Tarpey
- Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
- Anatomy and Regenerative Medicine Institute (REMEDI), School of Medicine, University of Galway, Galway, Ireland
- CÚRAM, Centre for Research in Medical Devices, University of Galway, Galway, Ireland
| | - Rachel Beatty
- Anatomy and Regenerative Medicine Institute (REMEDI), School of Medicine, University of Galway, Galway, Ireland
- SFI Centre for Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin, Dublin, Ireland
| | - Eimear Wallace
- Anatomy and Regenerative Medicine Institute (REMEDI), School of Medicine, University of Galway, Galway, Ireland
| | - Joanne O'Dwyer
- Anatomy and Regenerative Medicine Institute (REMEDI), School of Medicine, University of Galway, Galway, Ireland
| | - William Ronan
- Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
- Biomechanics Research Centre (BMEC), Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
| | - Garry P Duffy
- Anatomy and Regenerative Medicine Institute (REMEDI), School of Medicine, University of Galway, Galway, Ireland
- SFI Centre for Advanced Materials and BioEngineering Research Centre (AMBER), Trinity College Dublin, Dublin, Ireland
- CÚRAM, Centre for Research in Medical Devices, University of Galway, Galway, Ireland
| | - Eimear B Dolan
- Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
- Biomechanics Research Centre (BMEC), Biomedical Engineering, School of Engineering, University of Galway, Galway, Ireland
- CÚRAM, Centre for Research in Medical Devices, University of Galway, Galway, Ireland
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Regeenes R, Rocheleau JV. Twenty years of islet-on-a-chip: microfluidic tools for dissecting islet metabolism and function. LAB ON A CHIP 2024; 24:1327-1350. [PMID: 38277011 DOI: 10.1039/d3lc00696d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Pancreatic islets are metabolically active micron-sized tissues responsible for controlling blood glucose through the secretion of insulin and glucagon. A loss of functional islet mass results in type 1 and 2 diabetes. Islet-on-a-chip devices are powerful microfluidic tools used to trap and study living ex vivo human and murine pancreatic islets and potentially stem cell-derived islet organoids. Devices developed over the past twenty years offer the ability to treat islets with controlled and dynamic microenvironments to mimic in vivo conditions and facilitate diabetes research. In this review, we explore the various islet-on-a-chip devices used to immobilize islets, regulate the microenvironment, and dynamically detect islet metabolism and insulin secretion. We first describe and assess the various methods used to immobilize islets including chambers, dam-walls, and hydrodynamic traps. We subsequently describe the surrounding methods used to create glucose gradients, enhance the reaggregation of dispersed islets, and control the microenvironment of stem cell-derived islet organoids. We focus on the various methods used to measure insulin secretion including capillary electrophoresis, droplet microfluidics, off-chip ELISAs, and on-chip fluorescence anisotropy immunoassays. Additionally, we delve into the various multiparametric readouts (NAD(P)H, Ca2+-activity, and O2-consumption rate) achieved primarily by adopting a microscopy-compatible optical window into the devices. By critical assessment of these advancements, we aim to inspire the development of new devices by the microfluidics community and accelerate the adoption of islet-on-a-chip devices by the wider diabetes research and clinical communities.
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Affiliation(s)
- Romario Regeenes
- Advanced Diagnostics, Toronto General Hospital Research Institute, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
| | - Jonathan V Rocheleau
- Advanced Diagnostics, Toronto General Hospital Research Institute, Toronto, ON, Canada
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Departments of Medicine and Physiology, University of Toronto, ON, Canada
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Wang Y, Regeenes R, Memon M, Rocheleau JV. Insulin C-peptide secretion on-a-chip to measure the dynamics of secretion and metabolism from individual islets. CELL REPORTS METHODS 2023; 3:100602. [PMID: 37820726 PMCID: PMC10626205 DOI: 10.1016/j.crmeth.2023.100602] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/16/2023] [Accepted: 09/15/2023] [Indexed: 10/13/2023]
Abstract
First-phase glucose-stimulated insulin secretion is mechanistically linked to type 2 diabetes, yet the underlying metabolism is difficult to discern due to significant islet-to-islet variability. Here, we miniaturize a fluorescence anisotropy immunoassay onto a microfluidic device to measure C-peptide secretion from individual islets as a surrogate for insulin (InsC-chip). This method measures secretion from up to four islets at a time with ∼7 s resolution while providing an optical window for real-time live-cell imaging. Using the InsC-chip, we reveal two glucose-dependent peaks of insulin secretion (i.e., a double peak) within the classically defined 1st phase (<10 min). By combining real-time secretion and live-cell imaging, we show islets transition from glycolytic to oxidative phosphorylation (OxPhos)-driven metabolism at the nadir of the peaks. Overall, these data validate the InsC-chip to measure glucose-stimulated insulin secretion while revealing new dynamics in secretion defined by a shift in glucose metabolism.
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Affiliation(s)
- Yufeng Wang
- Advanced Diagnostics, Toronto General Hospital Research Institute, Toronto, ON M5G 1L7, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Romario Regeenes
- Advanced Diagnostics, Toronto General Hospital Research Institute, Toronto, ON M5G 1L7, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Mahnoor Memon
- Advanced Diagnostics, Toronto General Hospital Research Institute, Toronto, ON M5G 1L7, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
| | - Jonathan V Rocheleau
- Advanced Diagnostics, Toronto General Hospital Research Institute, Toronto, ON M5G 1L7, Canada; Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada; Departments of Medicine and Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada.
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Weir GC, Bonner-Weir S. Induction of remission in diabetes by lowering blood glucose. Front Endocrinol (Lausanne) 2023; 14:1213954. [PMID: 37409234 PMCID: PMC10318898 DOI: 10.3389/fendo.2023.1213954] [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: 04/28/2023] [Accepted: 05/29/2023] [Indexed: 07/07/2023] Open
Abstract
As diabetes continues to grow as major health problem, there has been great progress in understanding the important role of pancreatic beta-cells in its pathogenesis. Diabetes develops when the normal interplay between insulin secretion and the insulin sensitivity of target tissues is disrupted. With type 2 diabetes (T2D), glucose levels start to rise when beta-cells are unable to meet the demands of insulin resistance. For type 1 diabetes (T1D) glucose levels rise as beta-cells are killed off by autoimmunity. In both cases the increased glucose levels have a toxic effect on beta-cells. This process, called glucose toxicity, has a major inhibitory effect on insulin secretion. This beta-cell dysfunction can be reversed by therapies that reduce glucose levels. Thus, it is becoming increasingly apparent that an opportunity exists to produce a complete or partial remission for T2D, both of which will provide health benefit.
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Affiliation(s)
- Gordon C. Weir
- Joslin Diabetes Center, Harvard Medical School, Boston, MA, United States
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Serbis A, Giapros V, Tsamis K, Balomenou F, Galli-Tsinopoulou A, Siomou E. Beta Cell Dysfunction in Youth- and Adult-Onset Type 2 Diabetes: An Extensive Narrative Review with a Special Focus on the Role of Nutrients. Nutrients 2023; 15:2217. [PMID: 37432389 PMCID: PMC10180650 DOI: 10.3390/nu15092217] [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: 04/22/2023] [Revised: 05/04/2023] [Accepted: 05/06/2023] [Indexed: 07/12/2023] Open
Abstract
Traditionally a disease of adults, type 2 diabetes (T2D) has been increasingly diagnosed in youth, particularly among adolescents and young adults of minority ethnic groups. Especially, during the recent COVID-19 pandemic, obesity and prediabetes have surged not only in minority ethnic groups but also in the general population, further raising T2D risk. Regarding its pathogenesis, a gradually increasing insulin resistance due to central adiposity combined with a progressively defective β-cell function are the main culprits. Especially in youth-onset T2D, a rapid β-cell activity decline has been observed, leading to higher treatment failure rates, and early complications. In addition, it is well established that both the quantity and quality of food ingested by individuals play a key role in T2D pathogenesis. A chronic imbalance between caloric intake and expenditure together with impaired micronutrient intake can lead to obesity and insulin resistance on one hand, and β-cell failure and defective insulin production on the other. This review summarizes our evolving understanding of the pathophysiological mechanisms involved in defective insulin secretion by the pancreatic islets in youth- and adult-onset T2D and, further, of the role various micronutrients play in these pathomechanisms. This knowledge is essential if we are to curtail the serious long-term complications of T2D both in pediatric and adult populations.
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Affiliation(s)
- Anastasios Serbis
- Department of Pediatrics, School of Medicine, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece;
| | - Vasileios Giapros
- Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, St. Νiarhcos Avenue, 45500 Ioannina, Greece (F.B.)
| | - Konstantinos Tsamis
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece
| | - Foteini Balomenou
- Neonatal Intensive Care Unit, School of Medicine, University of Ioannina, St. Νiarhcos Avenue, 45500 Ioannina, Greece (F.B.)
| | - Assimina Galli-Tsinopoulou
- Second Department of Pediatrics, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, AHEPA University Hospital, Stilponos Kyriakidi 1, 54636 Thessaloniki, Greece;
| | - Ekaterini Siomou
- Department of Pediatrics, School of Medicine, University of Ioannina, St. Niarhcos Avenue, 45500 Ioannina, Greece;
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Marku A, Da Dalt L, Galli A, Dule N, Corsetto P, Rizzo AM, Moregola A, Uboldi P, Bonacina F, Marciani P, Castagna M, Catapano AL, Norata GD, Perego C. Pancreatic PCSK9 controls the organization of the β-cell secretory pathway via LDLR-cholesterol axis. Metabolism 2022; 136:155291. [PMID: 35981632 DOI: 10.1016/j.metabol.2022.155291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 07/29/2022] [Accepted: 08/11/2022] [Indexed: 11/15/2022]
Abstract
BACKGROUND Cholesterol is central to pancreatic β-cell physiology and alterations of its homeostasis contribute to β-cell dysfunction and diabetes. Proper intracellular cholesterol levels are maintained by different mechanisms including uptake via the low-density lipoprotein receptor (LDLR). In the liver, the proprotein convertase subtilisin/kexin type 9 (PCSK9) routes the LDLR to lysosomes for degradation, thus limiting its recycling to the membrane. PCSK9 is also expressed in the pancreas and loss of function mutations of PCSK9 result in higher plasma glucose levels and increased risk of Type 2 diabetes mellitus. Aim of this study was to investigate whether PCSK9 also impacts β-cells function. METHODS Pancreas-specific Pcsk9 null mice (Pdx1Cre/Pcsk9 fl/fl) were generated and characterized for glucose tolerance, insulin release and islet morphology. Isolated Pcsk9-deficient islets and clonal β-cells (INS1E) were employed to characterize the molecular mechanisms of PCSK9 action. RESULTS Pdx1Cre/Pcsk9 fl/fl mice exhibited normal blood PCSK9 and cholesterol levels but were glucose intolerant and had defective insulin secretion in vivo. Analysis of PCSK9-deficient islets revealed comparable β-cell mass and insulin content but impaired stimulated secretion. Increased proinsulin/insulin ratio, modifications of SNARE proteins expression and decreased stimulated‑calcium dynamics were detected in PCSK9-deficient β-cells. Mechanistically, pancreatic PCSK9 silencing impacts β-cell LDLR expression and cholesterol content, both in vivo and in vitro. The key role of LDLR is confirmed by the demonstration that LDLR downregulation rescued the phenotype. CONCLUSIONS These findings establish pancreatic PCSK9 as a novel critical regulator of the functional maturation of the β-cell secretory pathway, via modulation of cholesterol homeostasis.
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Affiliation(s)
- Algerta Marku
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Lorenzo Da Dalt
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Alessandra Galli
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Nevia Dule
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Paola Corsetto
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Angela Maria Rizzo
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Annalisa Moregola
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Patrizia Uboldi
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Fabrizia Bonacina
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Paola Marciani
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Michela Castagna
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy
| | - Alberico Luigi Catapano
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy; IRCCS Multimedica Hospital, Sesto San Giovanni, 20099 Milan, Italy
| | - Giuseppe Danilo Norata
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy; Centro SISA per lo studio dell'Aterosclerosi, Ospedale Bassini, 20092 Cinisello Balsamo, Italy.
| | - Carla Perego
- Dept of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, 20134 Milan, Italy.
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Wu TY, Liao EC, Chen YL, Lin YF, Liu SH, Lin HC, Chiu YC, Wu CZ, Lin JD, Pei D, Hsu CH. Elevated alanine aminotransferase is associated with biphasic insulin secretion in the healthy elderly Han Chinese population. J Int Med Res 2022; 50:3000605221115161. [PMID: 36124931 PMCID: PMC9511325 DOI: 10.1177/03000605221115161] [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: 11/17/2022] Open
Abstract
OBJECTIVE To evaluate the relationship between alanine transaminase (ALT) level and biphasic insulin secretion (BPIS) in healthy elderly Han Chinese individuals. METHODS This cross-sectional study enrolled healthy elderly participants aged ≥60 years that were part of a health examination programme. In order to explore the correlation and severity of the clinical condition, those with any possible confounding factors known to affect insulin secretion or liver function were excluded from the study. BPIS was calculated using an equation developed previously by this research team. RESULTS This study enrolled 39 845 healthy elderly individuals (19 058 males and 20 787 females). Participants were stratified into four quartile groups according to their ALT level. In both males and females, the increasing ALT quartiles (ordinal variable) were associated with greater values of log-transformed first-phase insulin secretion (FPIS) and second-phase insulin secretion (SPIS). The correlation and the linear regression model showed that increasing ALT level was significantly correlated with higher log-transformed FPIS and SPIS. CONCLUSIONS ALT was positively correlated with BPIS in a healthy elderly population in both men and women. Elevated ALT may serve as an indicating factor for developing metabolic syndrome and type 2 diabetes mellitus in healthy elderly individuals.
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Affiliation(s)
- Tzong-Yow Wu
- Department of Internal Medicine, National Taiwan University Hospital, Taipei
| | - En-Chih Liao
- Department of Medicine, MacKay Medical College, New Taipei.,Institute of Biomedical Sciences, MacKay Medical College, New Taipei
| | - Yen-Lin Chen
- Department of Pathology, Tri-Service General Hospital, National Defense Medical Centre, Taipei.,School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei
| | - Yung-Feng Lin
- School of Medical Laboratory Science and Biotechnology, College of Medical Science and Technology, Taipei Medical University, Taipei
| | - Shu-Hsiang Liu
- School of Nursing, College of Nursing, National Taipei University of Nursing and Health Science, Taipei
| | - Hua-Ching Lin
- Department of Surgery, Division of Colorectal Surgery, Cheng Hsin General Hospital, Taipei.,Department of Healthcare Information and Management, Ming Chuan University, Taoyuan
| | - Yi-Chou Chiu
- Department of Surgery, Division of General Surgery, Cheng Hsin General Hospital, Taipei
| | - Chung-Ze Wu
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Shuang Ho Hospital, Taipei Medical University, New Taipei.,Department of Internal Medicine, Division of Endocrinology and Metabolism, School of Medicine, College of Medicine, Taipei Medical University, Taipei
| | - Jiunn-Diann Lin
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Shuang Ho Hospital, Taipei Medical University, New Taipei.,Department of Internal Medicine, Division of Endocrinology and Metabolism, School of Medicine, College of Medicine, Taipei Medical University, Taipei
| | - Dee Pei
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei.,Department of Internal Medicine, Division of Endocrinology and Metabolism, Fu Jen Catholic University Hospital, New Taipei
| | - Chun-Hsien Hsu
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei.,Department of Family Medicine, Taipei City Hospital, Heping Fuyou Branch, Taipei.,Department of Family Medicine, Cardinal Tien Hospital, New Taipei
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Weir GC, Butler PC, Bonner-Weir S. The β-cell glucose toxicity hypothesis: Attractive but difficult to prove. Metabolism 2021; 124:154870. [PMID: 34480921 PMCID: PMC8530963 DOI: 10.1016/j.metabol.2021.154870] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 08/11/2021] [Accepted: 08/25/2021] [Indexed: 12/16/2022]
Abstract
β cells in the hyperglycemic environment of diabetes have marked changes in phenotype and function that are largely reversible if glucose levels can be returned to normal. A leading hypothesis is that these changes are caused by the elevated glucose levels leading to the concept of glucose toxicity. Support for the glucose toxicity hypothesis is largely circumstantial, but little progress has been made in defining the responsible mechanisms. Then questions emerge that are difficult to answer. In the very earliest stages of diabetes development, there is a dramatic loss of glucose-induced first-phase insulin release (FPIR) with only trivial elevations of blood glucose levels. A related question is how impaired insulin action on target tissues such as liver, muscle and fat can cause increased insulin secretion. The existence of a sophisticated feedback mechanism between insulin secretion and insulin action on peripheral tissues driven by glucose has been postulated, but it has been difficult to measure increases in blood glucose levels that might have been expected. These complexities force us to challenge the simplicity of the glucose toxicity hypothesis and feedback mechanisms. It may turn out that glucose is somehow driving all of these changes, but we must develop new questions and experimental approaches to test the hypothesis.
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Affiliation(s)
- Gordon C Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA.
| | - Peter C Butler
- Larry l. Hillblom Islet Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Susan Bonner-Weir
- Section on Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA, USA
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